Three different coagulants, δ-gluconolactone, magnesium chloride and papain were individually used to prepare fresh soft soymilk cheese from cooked soymilk. Key process parameters such as inoculum amount of starter culture, coagulant level and NaCl level were optimized by means of orthogonal array design. Soymilk cheeses obtained from these three coagulants were comparatively tested for the major physical and chemical properties and sensory characteristics. The results showed that the optimal levels of starter culture, coagulant and NaCl were the same for the preparation of soymilk cheeses using δ-gluconolactone or magnesium chloride, which were 0.020%, 0.20% and 1.0%, respectively; the optimal levels of starter culture, CaCl2, coagulant and NaCl for the preparation of papain-coagulated soymilk cheese were 0.010%, 0.02%, 0.05% and 1.0%, respectively. The soymilk cheeses obtained with the different coagulants had similar water contents. The papain-coagulated soymilk cheese received the highest sensory evaluation score, the magnesium chloride-coagulated one had the highest protein content, and the highest cheese productivity was achieved through coagulation with δ-gluconolactone. Although the cow,s milk cheese and the soymilk cheese prepared under the same technological parameters had similar protein contents, the fat content of the latter represented only one-third of that of the former and the latter showed higher water content and productivity and a slightly lower sensory evaluation score. Fresh soft soymilk cheese may be considered as a low-fat healthy substitute for fresh soft cow,s milk cheese.

AB-8 macroporous resin was used to purify commercial crude sasanquasaponin with low purity. The optimal purification process was determined as follows: 30 g/L crude sample solution was loaded followed by washing the resin with 30% ethanol aqueous solution to remove unwanted impurities including most pigments and partial proteins, and the adsorbed sasanquasaponin was finally eluted with 70% ethanol aqueous solution, resulting in a recovery of 55.5% and a purification factor of 1.86. After eighth repeated use, the adsorption and elution capacities of this resin were unchanged basically. Furthermore, the scale-up experiments demonstrated the suitability for industrial production. The LC-TOF-MS analysis indicated that the molecular weight of the purified sasanquasaponin mainly varied between 1170 and 1304 D. In addition, a sasanquasaponin compound with molecular formula C58H89O26 was identified and its structural formula was deduced.

The purpose of the present study was to develop a method to disrupt lotus bee pollen cell walls by one-step multienzymatic hydrolysis. Preliminary experiments were designed to investigate the effect of hydrolysis with different dosages of cellulase alone, 0.8% celluase and different dosages of pectinase, 0.8% celluase, 0.4% pectinase and different dosages of xylanase, or 0.8% celluase, 0.4% pectinase, 0.2% xylanase and different dosages of papain on the disruption of lotus bee pollen cell walls. We found that a mixture of cellulase, pectinase, xylanase and papain at a ratio of 4:2:1:3 was the best enzyme for the disruption of lotus bee pollen cell walls. Further, four hydrolysis parameters including pH, total enzyme dosage, temperature and material-to-water ratio for disrupting lotus bee pollen cell walls with this mixture of enzymes were optimized employing quadratic orthogonal rotation combination design. A mathematical model describing cell disruption percentage as a function of these four parameters was established. The optimal enzymatic hydrolysis parameters were found as pH 4.0, 12‰ of total enzyme dosage, 45 ℃ of hydrolysis temperature, and 1:14 (g/mL) of material-to-water ratio, resulting in a cell disruption percentage of 89.21%.

In this work, the effects of spray drying process parameters such as vacuum dehydration ratio, inlet air temperature and feeding rate on the recovery and antioxidant properties of protein hydrolysate powder were explored by response surface methodology. Mathematical predictive models were established, respectively, describing hdyrolysate recovery and reducing power, hydroxyl free radical scavenging activity and Fe2+ chelating activity as a function of these three spray drying process parameters. The prepared powder had certain antioxidant activity, which was dependent on the spray drying process parameters. Process parameters optimization was performed using the SAS software, and the optimized parameters were experimentally validated. In general good results for the spray drying of sweet almond protein hydrolysate could be achieved with a vacuum dehydration ratio of 0.5－0.6, an inlet air temperature of approximately 200 ℃, and a feeding rate of f 270－320 mL/h.

Response surface methodology (RSM) was employed to optimize the ultrasound-assisted extraction of essential oil from Sloanea hemsleyana seeds. Meanwhile, the chemical composition of the extracted essential oil was analyzed by GC-MS. The results showed that the optimal extraction conditions were cyclohexane as the best extraction solvent, single ultrasonic treatment for 3 s at a power level of 540 W followed by a 1-s interval, 18 min of total extraction time, and 1:8.6 of solid-to-liquid ratio, resulting in an oil yield of 94.53%. The essential oil obtained under these conditions was abundant in unsaturated fatty acids with a total content of 70.13%. The contents of oleic acid and linoleic acid were 53.95% and 16.18%, respectively.

Common bacteria in orange juice were analyzed to determine the lowest temperature needed for sterilizing orange juice. Simulated calculation of the ultra high temperature (UHT) sterilization of orange juice was performed using FLUENT software with 2 D axisymmetric model. The optimized sterilization process based on computational fluid dynamics (CFD) was validated experimentally with an error under 9.5%, indicating that CFD is applicable to simulate UHT sterilization process of orange juice. The optimal sterilization process required 13 seconds at 135 ℃ (408 K), 12 seconds at 140 ℃ (413 K), 12 seconds at 145 ℃ (418 K) and 11 seconds at 150℃ (423 K).  Based on the Carnot cycle efficiency, the consumption of mechanical energy at 408, 413, 418 K and 423 K was 5856, 6550, 6709 W and 7953 W, respectively. According to the principle of minimum energy consumption, the optimal sterilization process was sterilization at 135 ℃ (408 K) for 13 seconds.

An ultrasonic-assisted method to extract limonoids from navel orange residues left over from juicing using ethanol as the extraction solvent was proposed and optimized. Ethanol concentration, ultrasonic treatment time and extraction temperature were identified as main parameters that influence limonoids yield using Plackett-Burman design combined with the steepest ascent method. A regression equation reflecting the relationship between limonoids yield and these main affecting parameters was established based on Box-Behnken experimental design to optimize the three extraction parameters using response surface methodology. The optimal ethanol concentration, ultrasonic treatment time and extraction temperature were 82%, 18 min and 60 ℃, respectively. Under these conditions, the actual extraction yield of limonoids was 1.632‰, which was close to the predicted value of 1.651‰.

Immobilized pectinase was used to treat Red Fuji apple pulp to improve juice yield. One-variable-at-a-time experiments were conducted to investigate the effects of pH, hydrolysis temperature, enzyme dose and hydrolysis time on juice yield. Further, response surface methodology was employed to optimize the hydrolysis parameters. The optimal hydrolysis conditions were found as follows: pH 3.43, 1:15 of enzyme/substrate ratio, 49.4 ℃ of hydrolysis temperature, and 3.50 h of hydrolysis time. After tenth repeated use, the immobilized enzyme resulted in a juice yield of 62.421%, which was increased by approximately 13% compared with the control.

Objective: Orthogonal array design was used to optimize the microwave-assisted extraction of total flavonoids from Chinese date seeds. Methods: Total flavonoids were spectrometrically determined using rutin as a reference compound. The effects of microwave power, extraction time, temperature, solid-to-solvent ratio and ethanol concentration on the extraction yield of total flavonoids were investigated by one-factor-at-a-time experiments. Subsequently, these extraction parameters were optimized by orthogonal array design. Results: Five extraction parameters were ranked in descending order of their effect on the extraction of total flavonoids as follows: solid-to-solvent ratio＞extraction temperature＞extraction time＞ethanol concentration＞microwave power. Their optimal levels were 1:60 (g/mL), 60 ℃, 20 min, 50% and 500 W, respectively. Under these conditions, the extraction yield of crude total flavonoids was 10.14%, and the total flavonoid content of the extract obtained was 7.00%. Conclusion: The extraction efficiency of total flavonoids from Chinese date seeds is remarkably increased by microwave extraction and orthogonal array optimization.

Solid acid catalyst Fe2(SO4)3/γ-Al2O3 was prepared by maceration method and used to hydrolyze phytin to inositol at atmospheric pressure. Inositol yield was calculated to evaluated the activity of the prepared catalyst. The effects of maceration solvent concentration, maceration time and baking temperature on catalyst activity were explored. The optimal conditions for preparing Fe2(SO4)3/γ-Al2O3 were determined by response surface methodology (RSM) to be maceration solvent concentration of 50 mg/mL, maceration time of 4 h and baking temperature of 436 ℃. Under these conditions, Fe2(SO4)3/γ-Al2O3 was obtained and used to successfully hydrolyze phytin to achieve an inositol yield of 14.18% and a hydrolysis efficiency of 70.9%.

Objective: To explore the best synthetic process of Limonium bicolor polysaccharide-Fe (III) complex (LPC) and its physical and chemical properties. Methods: The synthetic process conditions were optimized by response surface methodology. The stability of LPC under physiological conditions was evaluated by its hydrolysis characteristics and reducibleness. Results: The optimal synthetic conditions were water bath temperature of 73℃, polysaccharides-to-C6H5Na3O7·2H2O ratio of 5:1 and reaction pH of 8. The prepared LPC was stable under physiological pH environment. Conclusion: LPC has excellent physicochemical properties and can be used as a new iron supplement.

The enzymatic hydrolysis of purple sweet potato was investigated for anthocyanin extraction. The effects of extraction temperature, pH, solid-to-solvent ratio, and enzyme amount on extraction rate of anthocyanins were explored by one-factor-at-a-time and orthogonal array design methods. The best extraction results were achieved by adding 0.25% α-amylase and 0.1% pectinase for hydrolysis at pH 5.5, 50 ℃, and a solid-to-solvent ratio of 1:15. The extract was adjusted to pH 2 and a concentration of 26.57 mg/100 mL for adsorption by AB-8 macro-porous resin at a flow rate of 1 mL/min and subsequent desoroption with 60% acidic ethanol solution at pH 3. Under these conditions, the extraction rate of anthocyanins was 2.71 mg/g, and the color value of the purified anthocyanins was 43.2.

The aim of this study was to develop the best process for hydrolyzing strawberry pulp with pectinase. Based on one-factor-at-a-time experiments, a three-factor and three-level Box-Behnken central composite design coupled with response surface analysis was employed to explore the effects of enzyme concentration, hydrolysis temperature and hydrolysis time on the yield of strawberry syrup. The results indicated that the optimal extraction conditions were achieved hydrolysis at 45 ℃for 5 h with 13.38 mg/L of enzyme. Under these optimal conditions, the predicted value of juice yield was 84.69%, while the actual value was 84.75%, suggesting a good fitting between the developed regression equation and actual values.

Box-Behnken experimental design and response surface analysis were used to optimize the extraction of flavonoids from Chrysanthemum nankingense. The results showed that the optimal process conditions for the extraction of flavonoids from Chrysanthemum nankingense were 78% ethanol solution as the solvent at a material-to-liquid ratio of 1:41, extraction time of 89 min, and extraction temperature of 68℃. Under these conditions, the yield of flavonoids was 2.88 mg/g.

The preparation of cross-linked guar gum was investigated by using epichlorohydrin as the cross-linking agent, sodium hydroxide as the catalyst and ethanol as the solvent in this study. The effects of epichlorohydrin amount, pH, reaction time, reaction temperature and alcohol concentration on the sediment volume of cross-linked guar gum was explored. The results showed that epichlorohydrin amount, pH, reaction time, reaction temperature and alcohol concentration had obvious impact on cross-linked reaction of guar gum. The optimal conditions for preparing cross-linked guar gum were epichlorohydrin amount of 8%, reaction time of 3.5 h, reaction temperature of 40 ℃ and ethanol concentration of 95%. Five reaction conditions were ranked in decreasing order of their effect on the sediment volume of cross-linked guar gum as follows: epichlorohydrin amount, reaction temperature, pH, reaction time and alcohol concentration. The thermal stability, enthalpy change, endothermic onset temperature, peak temperature and final temperature of cross-linked guar gum increased with increasing degree of cross-linking.

The hydrolysis of Dioscorea esculenta (Lour) Burkill Tubers by thermostable alpha-amylase for starch liquefaction was optimized by response surface methodology. Meanwhile, the hydrolysis process was studied kinetically. The results showed that under the optimized hydrolysis conditions: enzyme dosage of 0.15 mL/g, hydrolysis temperature of 90 ℃, hydrolysis pH of 6.0, substrate concentration of 70 mg/mL and hydrolysis time of 50 min, the DE (dextrose equivalent) was 55.69%. The vm and Km were determined to be 1.413 mg/(mL·min) and 69.97 mg/mL, respectively.

The application of pork fat oxidized by dual enzyme method for improving the flavor of natural pork essence was explored in this work. The optimal enzymatic reaction conditions for preparing oxidized pork fat, as determined using one-factor-at-a-time and orthogonal array design methods based on peroxide value (PV), were 300 μL of lipase, 400 μL of lipoxygenase and pH 8.88. Sensory evaluation revealed that pork essence based on oxidized pork fat obtained from enzymatic oxidation had a full aroma and outstanding characteristic flavor of porcine fat as compared with pork essences prepared from air-oxidized or non-oxidized pork fat. The results of solid phase microextraction coupled with gas chromatography-mass spectrometry (SPME/GC-MS) analysis indicated that these three pork essences had the same major flavor components, which included 1-(2-furanyl)-ethanone, 5-methyl-2-thiophenecarboxaldehyde, 3-methyl-thiophene, 2-pentyl-furan and 2-furfurylthiol. Moreover, pork essence based on enzymatically oxidized fat was richer in 2-methyl-furan and 5-methyl-2-thiophene formaldehyde.

A novel optimization method based on uniform design and function LINEST of Microsoft Excel was proposed to explore the extraction of proanthocyanidins from sea buckthorn seeds. The proposed multiple regression equation was calculated with the function LINEST. This method was not only a flexible method, but also could avoid high expenditure and fixed algorithm while using other professional software for data processing. The validation experiments showed that the extraction rate of proanthocyanidins from sea buckthorn seeds revealed an increase by 16.43%. This method is easy to extend and may hold promise for other scientific applications.

In order to establish an enzymatic method for collagen extraction from egg shell membrane, the influence of enzyme type, pH, enzyme dose, material-to-water ratio and extraction time on extraction efficiency was investigated and these extraction parameters were optimized one-factor-at-a-time experiments combined with an L9(34) orthogonal array design. The optimal extraction condition was hydrolysis for 5 h with 6% papain at normal temperature and a material-to-water ratio of 1:100 (g/mL), resulting in an extraction rate of 0.91%. As a result, an efficient extraction method was obtained. Collagen extraction from egg shell membrane by this method not only avoids environmental pollution caused by abandoned egg shell membrane, but also has great practical value in the collagen production industry.

The volatile composition of traditional fermented flour paste was analyzed by simultaneous distillation extraction (SDE) and gas chromatography and mass spectrometry (GC-MS). The volatile compounds separated from traditional fermented flour paste were identified by comparing their retention indices with those of reference compounds. Their relative contents were determined by peak area normalization method and their contents in traditional fermented flour paste were measured by internal standard method. A total of 113 compounds were identified accounting for 95.368% of the total peak area. Their total content in traditional fermented flour paste was 263.049 μg/g. These compounds included 10 aldehydes (11.862 μg/g), 25 esters (6.955 μg/g), 20 acids (140.596 μg/g), 14 hydrocarbons (1.934 μg/g), 9 alcohols (5.666 μg/g), 19 heterocycles (53.938 μg/g), 7 ketones (1.406 μg/g) and 9 other compounds (40.692 μg/g).

Objective: To establish a reversed-phase high-performance liquid chromatography (RP-HPLC) method for the determination of hyperoside in Tibetan Acanthopanax leaves from 5 different species. Methods: Hyperoside was identified by liquid chromatography-mass spectrometry (LC-MS). Hyperoside in samples were extracted by refluxing with 60% ethanol for 105 min. The chromatographic separation was achieved on a Kromasil C18 column at 30 ℃ through gradient elution using methanol as mobile phase A and 0.5% phosphoric acid at a flow rate of 1 mL/min. The detection wavelength was set at 355 nm. Results: A calibration curve equation describing the relationship between hyperoside concentration (Y) and peak area (X) was established as follows: Y＝2 × 106X ＋ 1.94883 (r＝0.990, n＝6). The calibration curve was linear over the concentration range of 0.17－2.55. The average spike recovery rate of hyperoside was 100.31% with a RSD of 0.95% (n＝9). Conclusion: A simple, accurate and repeatable method to determine hyperoside in Tibetan Acanthopanax leaves has been developed. Tender leaves of Tibetan Acanthopanax from the same species grown in Tibetan and Qiang Autonomous Prefecture and Ganzi Tibetan Autonomous Prefecture, Sichuan Province were found to be much richer in hyperoside than old ones. Low-temperature dried tender leaves of A. leucorrhizus (Oliv.) Harms var. fulvescens Harms & Rehd and A. setchuenensis Harms ex Diels had approximately equal hyperoside levels followed by tender leaves of A. giraldii Harms; tender leaves of A. sessiliforus Rupr had the lowest hyperoside level. Different drying methods were ranked in descending order from the highest to the lowest hyperoside content in dried A. leucorrhizus (Oliv.) Harms var. fulvescens Harms & Rehd as follows: shade drying ＞ processing into tea ＞ oven drying ＞ blanching ≈ microwave drying ≈ sun drying >> salting ＞ 1-month frozen storage ≈ 1-month frozen storage after blanching.

In order to explore the volatile aroma composition of Tianfuhao-branded Sauce fragrant chicken, volatile aroma components were isolated and identified by simultaneous distillation extraction-gas chromatography-mass spectrometry (SDE-GC-MS). 84 and 72 volatile aromatic compounds were identified from the ethyl ether and dichloromethane extracts from Tianfuhao-branded Sauce fragrant chicken, respectively. Altogether, 85 flavor compounds were found in both extracts, including 10 hydrocarbons, 24 aldehydes, 12 ketones, 2 ethers, 2 phenols, 19 alcohols, 4 acids, 4 ester and 8 nitrogen-containing or sulfur-containing or heterocyclic compounds. The major volatile aroma components with relatively higher peak area (＞1%) were hexanal, 1-methoxy-4-(1-propenyl)-benzene, hexadecanal, nonanal, eucalyptol, heptanal, 2-pentyl-furan, (E,E)-2,4-decadienal, octanal, 1-octen-3-ol, (E)-2-octenal, (E)-2-decenal, 3,7-dimethyl-1,6-octadien-3-ol, (S)-alpha, alpha-4-trimethyl-3-cyclohexene-1-methanol and 2,3-octanedione. Among these aroma components, aldehydes, ethers and nitrogen-containing and sulfur-containing and heterocyclic compounds were considered as the major flavor components in Tianfuhao Sauce fragrant chicken.

In order to explore the relationship of chemical composition with flavor, quality and safety of homemade sauerkraut, the acidity and the contents of total sugar, nitrite, protein and sodium chloride in five naturally fermented sauerkraut samples were determined by acid-alkali titration, direct titration, hydrochloric acid naphthyl ethylenediamine method, Kjeldahl nitrogen method and indirect precipitation titration method, respectively. The results showed that the acidity and the contents of total sugar, nitrate, protein and sodium chloride in five samples ranged from (0.283 ± 0.009)% to (0.891 ± 0.006)%, (3.96 ± 0.09)% to (4.37 ± 0.13)%, (0.167 ± 0.008) mg/kg to (2.67 ± 0.01) mg/kg, (0.0169 ± 0.003)% to (0.0218 ± 0.002)% and (0.412 ± 0.009)% to (0.447 ± 0.01)%, respectively. The differences in acidity and nitrite content may be considered as one of the causes of variations in  flavor, nutrition value and safety.

Forty eligible pure milk samples were collected and 40 adulterated milk samples were prepared by adding urea with various concentrations (1－20 g/L). Two-dimensional correlation spectroscopy was calculated under the perturbation of adulteration. Based on the 2D correlation infrared spectroscopic characteristics, the spectra in the range of 4200－4800 cm-1  were selected for quantitative and qualitative by partial least squares. There results showed that a 100% recognition rate of samples was achieved by partial least square-discriminate analysis (PLS-DA). The correlation coefficient (R) of calibration sets was 0.999, and the root mean square errors of cross validation (RMSECV) were 0.242. The R between the predicted values and actual values was 0.999, and the root mean square errors of prediction (RMSEP) were 0.57. Therefore, the developed models have good prediction capacity.

The identification of volatile compounds generated from the Maillard reaction of ascorbic acid and lysine at different reaction temperatures and reaction durations was performed using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Twenty-eight volatile compounds were identified, including pyrazines, aldehydes, furans, alcohols, benzenamines and quinolines. Sixteen pyrazines were the primary aromatic compounds. The effects of reaction temperature and time on the generation of volatile compounds, especially pyrazines, were investigated. The results showed that increased total amount of pyrazines was observed with increasing reaction temperature and time. Meanwhile, the generation of 2,5-dimethylpyrazine, 2-ethyl-3-methylpyrazine, 2-ethyl-5-methylpyrazine, 3-ethyl-2,5-dimethylpyrazine and 2-methylpyrazine revealed a significant increase during the reaction between ascorbic acid and lysine with increasing reaction temperature, and an obvious high yield of 2,5-dimethylpyrazine was achieved due to increasing reaction time.

Volatile compounds in Camellia azalea flowers at different stages during flower development, in their different parts and at different hours of a day were analyzed by solid phase micro-extraction and gas chromatography-mass spectrometry (GC-MS). Totally 8, 20, 21 and 17 volatile compounds were identified in early-stage, full bloom and withering flowers, respectively. Volatile compounds were released mainly during the early flowering and full bloom stages. During flower development, the content of alcohols revealed a gradual increase. Alkenes, esters and alkanes revealed an initial increase and a final decrease, while aldehydes and ketones revealed a decrease trend during the whole process. Totally 20 compounds were identified in sepals, 22 in petals, 21 in stamens and 13 in pistils. The major parts releasing volatile components were petals and stamens. Alkanes were the most dominant volatile compounds in sepals, stamens and petals, accounting for 49.86%, 51.59% and 44.66% of the total volatiles, respectively, while the most dominant volatile compounds in pistils were aldehydes and ketones with a relative content of 83.87%. An obvious intraday variation was observed in the relative contents of volatile compounds in Camellia azalea flowers. The peak hours for releasing alkenes, alcohols, esters and alkanes were 8:00 to 12:00, while higher release levels of aldehydes and ketones were found from 14:00 to 18:00.

According to the iap gene of Listeria monocytogenes, two pairs of specific primers were designed, and then a rapid loop-mediated isothermal amplification (LAMP) assay for detecting Listeria monocytogenes in foods was developed using real-time turbidity of the amplification byproduct magnesium pyrophosphate as the positive criterion. Twenty-nine bacterial strains were used to evaluate the specificity of the LAMP method. Our results showed that all tested Listeria monocytogenes were positive, while other strains were negative to LAMP detection, suggesting that this LAMP method was highly specific to the target bacteria. The sensitivity for cultivated Listeria monocytogenes and its contaminated foods were was 8 CFU and 12 CFU per test tube, respectively. The LAMP method developed in this study provides a sensitive, rapid and simple approach for the detection of Listeria monocytogenes.

Volatile compounds in different parts of sturgeon were analyzed by solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) to find out the major compounds responsible for the characteristic smell and fishy odor. Over 60 compounds including aldehydes, ketones, alcohols, hydrocarbons and acids were identified in the ventral, tergal, tail, skin, gill and liver of the fish. Among the identified compounds, aldehydes, alcohols and hydrocarbons were predominant. Six different parts of sturgeon varied in the types and relative contents of volatile compounds and were richer in aldehydes and hydrocarbons than other identified compounds. The contents of alcohols in sturgeon liver, skin and gill were 32.08%, 44.96% and 5.51%, respectively. The lowest amount of volatile compounds was found in tergal meat. Sturgeon was mainly characterized by grassy, fishy and fatty odor. The major compounds contributing to the fishy odor were hexanal and 1-octen-3-ol.

A headspace solid-phase microextraction and gas chromatography-tandem mass spectrometric (HS-SPME- GC-MS/MS) method was proposed for the simultaneous determination of three chlorophenols 2,4,6-trichlorophenol (TCP), 2,3,4,6-tetrachlorophenol (TeCP), pentachlorophenol (PCP) and two chloroanisols including pentachloroanisol (PCA) and 2,4,6-trichloroanisol (TCA) in wine. Chlorophenols from wine samples were acetylated and then analyzed by GC-MS/MS in a multi-reaction monitoring (MRM) mode. Four extraction parameters including extraction fiber, ion strength, extraction temperature and extraction time were optimized. The results showed that the limit of detection of this method was 0.1 ng/L. The average spike recovery rates of five analytes in a positive sample were 86.0%－105.9% with a RSD less than 16.5% (n = 5). This method was simple, effective, sensitive and therefore applicable to monitor cork taint in exported and imported wine.

A new method using β-glucosidase activity was proposed to detect honey adulteration. The activities of β-glucosidase in honey from different plants, different storage conditions, and different proportions of high-fructose rice syrup were determined. The results showed that β-glucosidase activity was detectable in honey samples from different plants; however, no β-glucosidase activity was detected in honey adulterated with high-fructose rice syrup. β-glucosidase activity in rape honey showed little change during 11 months of storage at －18 ℃, 4 ℃, room temperature or 30 ℃. With increasing high-fructose rice syrup adulteration, β-glucosidase activity revealed a linear decline. In conclusion, β-glucosidase activity can be considered as an effective indicator for the identification of honey adulteration.

Objective: To monitor the Salmonella contamination status of commercial eggs, detect the pathogenesis and pathogenicity island (SPI) gene of Salmonella isolates and their correlation. Methods: Commercial eggs were collected from supermarkets in different cities in Shaanxi province. The eggshell membranes were harvested for isolating and culturing Salmonella in eggs. The strain isolates were identified through the PCR amplification of the special gene invA from Salmonella. The isolated strains were used for testing the pathogenesis for chicken. According to the sequence of SPI genes published in GenBank, PCR primers were designed to amplify and identify the SPI genes of core proteins. Results: A total of 30 Salmonella strains were isolated from 1100 commercial eggs that were purchased from 55 supermarkets. According to animal pathogenesis tests, 13 strains were pathogenic and 7 strains were strongly pathogenic among these Salmonella strains. The carrying rate of SPI gene was 60% for SPI-1, 73.3% for SPI-2, 100% for SPI-3, 90% for SPI-4 and 76.7% for SPI-5. Meanwhile, SPI-1 and SPI-2 revealed an obvious correlation with pathogenesis. Conclusion: The isolation rate of Salmonella from commercial eggs observed in this study is 2.73%. SPI-1 and SPI-2 have a positive correlation with pathogenesis.

An HILC-MS/MS method was developed to simultaneously determine melamine and cyanuric acid in food contact packaging materials. Samples were extracted with H2O, 4% acetic acid (V/V), 10% ethanol isooctane (V/V) and olive oil separately, kept in a 70 ℃ incubator for 2 h and then filtered through a 0.2 μm microporous membrane prior to injection into an HILC-MS/MS system. Melamine and cyanuric acid were separated, identified and quantified on HILC column by gradient mobile phase and monitored in a positive/negative electrospray ionization and multiple reaction monitor (MRM) mode. A good linear range was achieved over the concentration range of 1－100 ng/mL and 2－200 ng/mL for melamine and cyanuric acid in different stimulants, respectively. The limits of detection and limits of quantification were in the range of 0.4－0.8 ng/mL. The recovery rates of melamine and cyanuric acid were 134.0%－86.2% and 156.0%－78.9% with RSDs of 6.44%－17.93% and 5.95%－11.78%. This method was simple, rapid, and accurate, and suitable for the determination of melamine and cyacuric acid in food contact packaging materials.

Supercritical carbon dioxide fluid (SCDF) extract from litchi seeds was prepared and analyzed by GC-MS for volatile composition. The extraction efficiency of SCDF extract was 4.26%. A total of 67 compounds were identified from the extract, mainly including phytosterols, terpenoids, unsaturated fatty acids, hexadecanoic acid, fatty acid ester and vitamin E with relative contents of 31.3%, 25.7%, 12.03%, 9.63%, 7.53% and 7.21%, respectively.

In order to analyze the properties of volatile components in ginkgo fruits stored in different conditions, an electronic nose FOX4000 was used to detect the volatile odors of ginkgo fruits treated with different preservatives and packaged with different materials after 140 days of storage at 4 ℃. The results indicated that the cumulative contribution rates of the fist and second principal components and discrimination index for ginkgo fruits with different material packaging treatments were 99.44% and 94, respectively, while those for ginkgo fruits with different preservative treatments were 99.48% and 86, respectively. Electronic nose allowed sensitive distinguishing among the significantly different volatile odors of ginkgo fruits due to the different preservation and packaging treatments.

The effect of industrial processing on the formation of microflora in duck carcasses was studied in the present work. Through traditional microbial culture, the number of microorganisms on workshop contact surface and carcass surface as well as in pre-chilling water during refrigeration was determined. The results showed that the air, chilling water and environment contact surface in workshops were the major sources of contamination and microflora formation. The number of bacteria in environment and on carcass surface displayed a declining trend. Before defeathering, a number of bacteria were transferred from duck surface to the environment; on the other hand, an reversed order was observed after defeathering, which resulted in a periodic rise of bacteria at several steps such as defeathering and evisceration process. The pre-chilling process had a decisive effect on the quality of final products due to the various decontamination effects.

Objective: To comparatively analyze bioactive components in seeds and flesh of Schisandrae chinensis Fructus. Methods: The contents of lignan in seeds, flesh and whole fruit of Schisandrae chinensis Fructus were determined by high performance thin layer chromatography (HPTLC). Sulfuric acid-phenol method was used to quantify sugar. After trifluoroacetic acid hydrolysis, the monosaccharide composition of the flesh was analyzed by HPTLC. Results: Lignans in Schisandrae chinensis Fructus were mainly present in the seeds, and total sugar content was 169.34 mg/g in the flesh and 5.366 mg/g in the seeds. The alcohol-soluble, alcohol-insoluble and polysaccharide components were 117.06, 75.67 mg/g and 12.37 mg/g in the fresh, respectively. The alcohol-soluble fraction was mainly composed of glucose. The polysaccharide fraction was mainly composed of glucose and galactose. Conclusion: Bioactive components reveal a significant difference between seeds and flesh of Schisandrae chinensis Fructus. 

The major biochemical components in Anji Baicha, a specific species of tea introduced in Qionglai County, Hongya County and Gao County in Sichuan from Zhejiang were analyzed. The results showed that Anji Baicha grown in Sichuan was rich in amino acids with total content of (69.70± 2.43)－(82.66 ± 8.07) mg/g. The total content of 20 kinds of free amino acids was (60.43 ± 4.45)－(77.75 ± 18.88) mg/g, and the content of theanine was (25.91 ± 0.20)－(37.31 ± 0.63) mg/g, accounting for 40.28% －54.98% of the total free amino acids. The total amount of catechins was (4.97 ± 0.16)%－(7.37 ± 0.08)%, and the contents of polyphenols, caffeine and water extract were (14.22 ± 0.37)%－(23.78 ± 0.47)%, (2.87 ± 0.02)%－(3.30 ± 0.13)% and (42.30 ± 3.65)%－(47.82 ± 3.91)%, respectively. Compared to its original growing region, the total content of amino acids in Anji Baicha grown in Sichuan was higher, and the contents of polyphenols and caffeine revealed similar levels. However, catechin revealed a reduction by 48.9%－60.6%. Therefore, the excellent characteristics of high amino acid content and low IP/AA ratio in Anji Baicha grown in Sichuan were well maintained. These biochemical characteristics will provide a theoretical reference for future studies on quality improvement. 

A new quick method for the determination of difloxacin hydrochloride residue in pork and chicken livers using solid phase extraction followed by flow injection chemiluminescence analysis was presented based on the inhibition of chemiluminescence generation from the reaction between luminol and hydrogen peroxide by difloxacin hydrochloride. The results showed that an excellent linear relationship between chemiluminescence intensity and negative logarithm of difloxacin hydrochloride concentration was observed in the range of 1.00 × 10-5－1.00×10-9 mg/mL. The limit of detection for difloxacin hydrochloride was 4.07 × 10-9 mg/mL. The precision was 0.93% (relative standard deviation, RSD) for eleven replicate determinations. Therefore, this method can be used for the determination of difloxacin hydrochloride in animal liver with satisfactory results.

The fatty acid composition of 16 vegetable oil samples and animal fat from 4 species was analyzed by GC-MS for a detailed understanding the percentages of various fatty acids and their nutritional characteristics. The sample pretreatment was achieved through mythyl esterification in the presence of KOH/MeOH. The major fatty acids in the edible fats and oils included palmitic acid, stearic acid, oleic acid, 11-octadecenoic acid, linoleic acid, linolenic acid, 11-eicosenoic acid and erucic acid. Among them, a very high difference was in the ratios among saturated, monounsaturated and polyunsaturated fatty acids. Meanwhile, the ratio between n-6 and n-3 polyunsaturated fatty acids also exhibited an obvious difference.

The effect of ultra high pressure (UHP) treatment on the aromatic quality of natto was studied. Natto samples were treated at 200, 400 or 600 MPa for 10 min, and aromatic compounds were extracted by solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that after UHP treatment, the types and contents of aroma compounds in natto had a significant change (P < 0.05). 2-Methyl-3-pentanone dropped to a undetectable level and another compounds such as hexanal and 2-pentyl furan were newly detected. The contents of ketones, esters and alcohols increased, while the contents of acids, aldehydes and pyrazines decreased. After UHP treatment at 400 MPa for 10 min, the contents of ketones, esters and alcohols revealed an increase by 13.11%, 117.29% and 46.91%, respectively; in contrast, the contents of acids, aldehydes and pyrazines exhibited a decrease by 50.59%, 90.92% and 16.17%, respectively. Following UHP treatment, more typical aroma of natto was achieved. The contents of acetic acid and benzene that have an unfavorable impact onthe aroma of natto revealed a significant reduction (P < 0.05).

A method for the selective detection of viable cells of Salmonella in meat and meat products was developed using propidium monoazide (PMA) staining in combination with conventional PCR (PMA-PCR). Exposure time and PMA concentration were optimized to find optimal PMA-based PCR conditions for distinguishing between dead and viable cells. The results showed that the optimal light exposure time to activate PMA in dead cells and to photolyze free PMA in solution was 15 min. PMA at a dose of 10 μg/mL or less could not inhibit PCR amplification of DNA derived from viable cells of Salmonella. The minimum concentration of PMA to completely inhibit PCR amplification of DNA derived from heat-killed cells was 4 μg/mL. After PMA treatment, viable Salmonella cells in a mixture containing different proportions of viable and dead cells could be selectively detected by PCR, and the minimum detection level was 20 CFU/PCR. An excellent linear relationship was observed between relative fluorescent intensity of DNA bands and lgCFU in the range of 20－2 × 105 CFU/PCR. Among 30 meat and meat product samples, two samples were detected by the developed PMA-PCR method as being positive after 6 h enrichment with average amounts of 2.5 × 103 CFU/mL and 3.4 × 103 CFU/mL for viable Salmonella cells, respectively.

The contents of hydrolyzed amino acids and free amino acids in rose apple fruits were determined by reversed phase high performance liquid chromatography (RP-HPLC). Totally 18 kinds of amino acids were identified. Total content of human essential amino acids was 33.49%. These results showed that rose apple is rich in nutrients. The flavor of rose apple was also investigated. It was found that the contents of Met and Cys were insufficient as human essential amino acids, which resulted in poor nutritional value of rose apple. On the other hand, abundant Glu and Asp made a substantial contribution to tasty flavor of rose apple.

In order to explore a rapid method for the determination of salbutamol (SAL) residues in animal urine, the impacts of extraction solvent, β-CD concentration for synergistic sensitization with small alcohol molecules and pH on determination results were explored. The optimal extraction solvent was isobutanol, aβ-CD concentration of 5 mmol/L was found optimal, and under these conditions, the fluorescence intensity of SAL was enhanced remarkably by adding 4% ethanol. The optimal pH was 9. The precision (RSD), recovery rate and detection limit of this method were 0.013%, 96.57% and 0.8 μg/L, respectively. The whole course of SAL determination by this method could be completed within 10－15 min. This method was simple, efficient, and suitable for the in situ determination of SAL residue.

Three species of microalga were analyzed for oil content, fatty acid composition and physiochemical properties. The results showed that the oil contents of D. salina, Spirulina and Chlorella were 17.69%, 6.36% and 11.64%, respectively. Palmitic acid, oleic acid, linoleic acid and linolenic acid were the major fatty acids in D. salina oil and Chlorella oil, while the major components of Spirulina oil were palmitic acid, linoleic acid and sub-linolenic acid. The oils from D. salina, Spirulina and Chlorella had high C/H levels, which were 7.35, 7.32 and 7.58, respectively. The acid value was 12.64 mg KOH/g for D. salina oil, 17.65 mg KOH/g for Spirulina oil and 9.8 mg KOH/g for Chlorella oil, respectively. The heating values were 36.07, 37.01 MJ/kg and 35.00 MJ/kg, respectively. The three microalga oils revealed high acid value and viscosity and poor fluidity.

A mathematical model for water content of small red beans with respect to relative dielectric loss factor, bulk density and temperature was set up and validated under a signal frequency of 500 kHz. The effects of measurement signal frequency (1 kHz－1 MHz), bulk density (747－851 kg/m3) and temperature (5－40 ℃) on relative dielectric loss factor were studied, and the mechanism underlying the change in relative dielectric loss factor was analyzed in theory. The results indicated that dielectric loss factor of small red beans revealed a decreasing trend with increasing signal frequency in the range of 1 kHz－1 MHz, but presented an opposite trend as the water content, bulk density and temperature increased. A quadratic model characterizing the relationship of water content with relative dielectric loss factor, bulk density and temperature was established with a determination coefficient of 0.9882.

The quality change of ghee produced in Inner Mongolia, China during storage at 4, 25 or 32 ℃ was evaluated using electronic nose, and the evaluation results were compared with the changes in sensory characteristics, acid value and POV value to explore the applicability of electronic nose for quality evaluation of ghee. The results showed that ghee at 32 ℃ had a storage life of 4 months. During this storage period, the acid value revealed an obvious increase, and the peroxide value exhibited an initial increase followed by a decline. Ghee became rancid and inedible due to rancidity during the final stages of storage. However, unobvious changes in various chemical indices of ghee were observed during storage at 4 ℃. In addition, fingerprinting analysis of headspace odor samples from ghees stored at different temperatures for the same periods was performed using electronic nose. The data obtained were analyzed using LDA (linear discriminant analysis) method to show high similarity with those obtained from physiochemical analysis, demonstrating the applicability of electronic nose for quality evaluation of ghee.

A high performance liquid chromatography method was established for the determination of 1utein and zeaxanthin in Pangasius bocouti. The chromatographic separation was achieved on a C30 column using a mobile phase made up of acetonitrile, methanol and spasmolytol (75:25:0.05, V/V) by gradient elution. The detection wavelength was set at 450 nm, and an external standard method was used to quantify 1utein and zeaxanthin. An excellent linear relationship of this method for 1utein and zeaxanthin was observed (R2 ＞0.999). The average spike recovery rates of 1utein and zeaxanthin were 85.43%－96.60% and 83.18%－96.18% with relative standard deviations of 5.01%－7.15% and 4.60%－8.43%. The limit of detection was 0.008 mg/kg for 1utein and 0.003 mg/kg for zeaxanthin. This method was sensitive, repeatable, and suitable for the determination of 1utein and zeaxanthin aquatic products.

A simple HPLC method was developed to determine organic acids (oxalic, tartaric, malic, isocitric, shikimic, lactic, acetic, citric and succinic acids) in blueberry juice and wine. The HPLC separation was achieved on C18 column (4.6 mm× 250 mm, 5 μm) at room temperature. The mobile phase (pH 2.0) was 4% NH4H2PO4 at a flow rate of 1 mL/min. The detection wavelength was set as 210 nm. The average recovery rate of this method was 99.52% with RSD of 0.019%. 

A new method for the determination of trace lead in preserved eggs was developed using flow injection (FI) coupled with flame atomic absorption spectrometry (FAAS). During the elution procedure, the eluent was pumped into knotted reactor (KR) by the suction of the peristaltic pump. By using this new method, the dispersion of the analyte was decreased significantly, and high absorbance peak value was achieved. Emptying procedure was added in order to ensure the precision and repeatability of each determination. An enrichment factor (EF) of 11.6 was achieve in the determination of 500 μg/L lead through sampling at a flow rate of 6.0 mL/min for 60 s, while the EF obtained using the traditional method was 3.7. The limit of detection (3σ) and determination frequency of this method were 3.91 μg/L and the 41 h-1, respectively. The precision RSD for 11 replicate determinations was 1.8%. Using 0.1‰ triethannolamine as the masking reagent, the recovery rates of lead from preserved egg white and yolk were determined to be 97.0%－99.5%.

Objective: To establish a UV spectrometric method to determine diethylhexyl phthalate (DEHP) in purified drinking water. Methods: DEHP in drinking water was extracted with n-hexane, blow-dried with nitrogen gas, and brought to a final volume with methanol. Experimental conditions for DEHP determination were optimized.  Results: A standard curve equation was built as follows: y ＝1.5347x＋0.0266 with linear correlation coefficient of 0.9970. The relative standard deviations of precision and reproducibility were 0.644% and 0.5742%, respectively. The average spike recovery rates were 88.89%－99.73%. Conclusion: This method is characteristics of simple operation, fast determination and satisfactory results.

Objective: To establish and compare two detection methods for human norovirus (HuNoV) in fruit (grape) and vegetable (green onion) samples using porcine gastric mucin-conjugated magnetic beads (PGM-MB) and polyethylene glycol 8000 (PEG8000), respectively. Methods: 1 RTU was defined from a consistently (triplicate) positive qRT-PCR signal of viral RNA extract with 4 × 10-6 dilution. A standard curve (1 to 10000 RTU) was established to convert Ct values to corresponding RTUs with an equation of y (Ct) = －3.6967 lg (RTU) ＋39.12 with R2 of 0.999. Green onion and grape samples were inoculated with various amounts of HuNoV, eluted and concentrated using PGM-MB or PEG8000 method. Viral RNA was extracted and quantified by qRT-PCR. Student,s t-test was used for statistical analysis. Results: The virus recovery rate by PGM-MB method ((31.61 ± 15.04)%) was significantly higher than that obtained by PEG precipitation method ((6.09 ± 1.56)%) at all doses of HuNoV inoculated onto grapes (P ＜0.001). For virus-inoculated green onions, the virus recovery rates from higher inoculation doses (625 RTU and 125 RTU) were comparable between both methods. However, the virus recovery rate by PGM-MB method from a lower dose of HuNoV (25 RTU) inoculated onto green onion samples was significant higher ((4.49± 0.79)%) than that from PEG precipitation method ((1.93 ± 0.18)%). In addition, PGM-MB method showed a lower detection limit than PEG precipitation method. Conclusion: PGM-MB method requires less time than PEG precipitation method, produces higher yield of HuNoV from various food samples, and hence exhibits higher sensitivity.

In the present study, four pathogenic strains named as 091, 089, 086 and 071, respectively were isolated from infected black amber plum, and one pathogenic strain named as 072 from infected Bayuecui peach during postharvest storage. Morphological observation and rDNA ITS analysis indicated that all five pathogenic strains were Monilinia fructicola. The result obtained also revealed that strains 091 and 089 had a close phylogenetic relationship with Monilinia fructicola (FJ515894). Metabolic fingerprinting suggested that these five strains had the same ability to metabolize 56 carbon sources including 51 optimal ones and 5 unutilized ones. Monilinia fructicola 091 and 089 shared the most similar metabolic fingerprints, whereas Monilinia fructicola 086, 071 and 072 were the most similar. These studies demonstrated that both rDNA ITS analysis and carbon metabolic fingerprinting allows distinguishing among the Monilinia fructicola strains isolated and may be considered as being comparable.

Near-infrared (NIR) spectroscopy was applied to rapidly and non-destructively distinguish between bruised and intact apples and identify different apple varieties. Besides, the effect of different discrimination methods on the distinguishing and identification models obtained was investigated. The results indicated that discrimination models were developed based on the first five principal components in the range from 12000 cm-1 to 4000 cm-1 from the NIR spectra of bruised and intact apples subjected to wavelet pretreatment using three different discrimination methods, multilayer perceptron (MLP) neural network, radial basis function (RBF) neural network and Fisher line discriminant analysis (Fisher-DA) with discrimination accuracy rates of 97.8%, 87.2% and 84.8%, respectively for unknown samples. The Fisher linear discriminant analysis model established based on multiple linear regression and the loading weights showed a discrimination accuracy rate of 89.1% compared with 100% for the model established using partial least squares discriminant analysis (PLS-DA). The discrimination accuracy rates of the PLS-DA model for the training and validation sets were both 100%, and therefore the PLS-DA model was superior to others. A better discrimination model was established based on the first six principal components of the NIR spectra of different apple varieties subjected to smoothing pretreatment in the full wavelength range of 12000－4000 cm-1 than in the empirical range of 8000－4500 cm-1 with discrimination accuracy rates of 90.9% and 92.1% for the predication and validation sets, respectively. In conclusion, the combination of NIR and chemometrics can provide a rapid and non-destructive approach to discriminate whether apples are bruised and identify different apple varieties.

Objective: A reversed-phase high performance liquid chromatography (RP-HPLC) method was established to simultaneously determine 4 capsaicinoids including capsaicin, dihydrocapsaicin, nordihydrocapsaicin and homocapsaicin in chili peppers. Methods: Capsaicinoids were separated on a Nucleosil C18 column (4.6 mm × 250 mm, 5 μm) using a mobile phase composed of acetonitrile and water through gradient elution at a flow rate of 1.0 mL/min. The detection wavelength was 280 nm. Results: An excellent linear relationship between peak areas and concentrations of 4 capsaicinoids in the range of 1.0 －160.0 μg/mL with correlation coefficients of 0.9965－0.9993 was observed. The precision and stability RSD (%) of this method were lower than 2.7%. The average recovery rates of 4 capsaicinoids was 97% －99% (n＝6). The contents of 4 capsaicinoids in 30 chili pepper varieties revealed an obvious difference. Conclusion: This method has been successfully used to determine 30 chili pepper varieties with stable and reproducible results. Moreover, piquancy taste is obvious when the total content of capsaicin and dihydrocapsaicin is more than 0.1%.

In order to examine the quality of fresh pork on the market, eating quality parameters including cooking loss, shear force, color, pH, total volatile basic nitrogen (TVB-N) and total bacterial count of fresh pork stored at 25, 20, 15, 10 ℃ and 4 ℃ were analyzed comparatively. The results showed that fresh pork stored at 25, 20 ℃ and 15 ℃ did not reveal the optimal consumption time; however, fresh pork stored at 10 ℃ and 4 ℃ revealed the optimal consumption time after storage for 36 hours and 48－72 hours, respectively. Fresh pork stored at 25, 20, 15, 10 ℃ and 4 ℃ could maintain the optimal consumption time within 12, 18, 36, 48 hours and 96 hours. Within 48 hours, fresh pork stored at 10 ℃ had no significant difference in cooking lose, color (L* value and a* value) and TVB-N, but had better shear force when compared with the fresh pork stored at 4 ℃.

SDE-GC/MS was used to explore the effect of antioxidants on volatile flavor components of Sichuan traditional bacon during chilling storage at 5 ℃. The results showed that freshly prepared Sichuan traditional bacon contained 67 volatile components; the number of volatile components varied to 75, 64 and 63 after 120 d of storage with treatments A (vacuum packaging), B (addition of 0.4 g/kg tea polyphenols and then vacuum packaging) and C (addition of 0.5 g/kg sodium D-isoascorbate and then vacuum packaging), respectively. The number of phenols, hydrocarbons and carbonyl compounds changed from 56 to 55, 45 and 44 with a relative content change from 69.44% to 59.30%, 60.51% and 61.87%, respectively. The relative content of phenols as the major flavor components changed from 34.43% to 24.26%, 28.06% and 33.41%, respectively. The relative contents of phenol, phenol, 2-methoxy, 2-methoxy-5-methylphenol, nonanal, acetyl furan, 3-furanmethanol and benzaldehyde after B and C treatments were higher than those in the samples subjected to A treatment. Therefore, antioxidants can significantly inhibit the reduction of characteristic flavor substances in bacon during chilling storage.

In order to explore the quality and safety of sliced cooked ham, the dynamic characteristics of vacuum packaged sliced cooked ham under different storage temperatures were monitored. The dynamic changes of quality parameters such as sensory quality, colony number, coliform number, color, pH, water content and water retention as well as texture characteristics of sliced cooked ham stored at 0－4 ℃ and 7－11 ℃ were analyzed. The results indicated that the quality change of sliced cooked ham during storage under two different temperature conditions revealed a similar trend. Slower colony growth and more stable water content, pH, water retention and textural properties of sliced cooked ham stored at 0－4 ℃ were observed when compared with sliced cooked ham stored at 7－11 ℃. Therefore, low temperature storage is beneficial for the stability and safety of sliced cooked ham products, thus prolonging the shelf life.

The effect of garlic extract treatment at doses of 0, 100, 150 mg/kg and 200 mg/kg on the quality of vegetable-fish balls during cold storage was examined by measuring sensory characteristics such as sensory score, texture and whiteness, total viable count (TVC), and physiochemical parameters such as pH, total volatile basic nitrogen (TVB-N) and thiobartituric acid (TBA) over a period of every 5 days. The results indicated that the treatment group revealed a significantly preservative effect in comparison with the control group; the best preservative effect was obtained at a dose of 200 mg/kg, resulting in an extension of shelf life by 7－8 days. According to the differences in TVC, pH, TBA and TVB-N between both groups, garlic extract exhibited an obvious inhibitory effect on bacterial growth and slowed down the oxidative deterioration of protein and fat, thus extending the shelf life of fish balls.

In this study, lipid oxidation and quality change of frozen dumplings stuffed with different amounts of pork fat (0－40%) and different frozen storage periods (0－6 months) were examined. Lipid oxidation was evaluated by peroxide value (POV) and thiobarbituric acid-reactive substances (TBARS). The quality change was measured by cooking loss, texture and a*-value (red degree) of meat stuffing. The results showed that the POV value and TBARS revealed an obvious increase with increasing fat addition and storage time. The increase of fat addition also caused a decrease in a*-value, springiness, hardness, chewiness and cohesiveness, and an increase in cooking loss.

In order to clarify the possibility of edible film as a substitute for traditional preservatives, the fresh-keeping effect of Coptis chinensis Franch (50% ethanol extract from Rhizoma Coptis)-chitosan film on Citrus sinensis (L.) cv. Olinda Valencia orange fruits was investigated. The results showed that the composite coating could significantly decrease disease index and weight loss rate as well as decay fruit rate. Meanwhile, it could also decrease respiration intensity, maintain higher contents of titratable acids and vitamin C and stabilize the content of soluble solids. In addition, the composite coating could enhance the activity of catalase (CAT) in valencia orange fruits. Moreover, compared with the traditional preservation treatment, this coating could maintain higher activities of CAT and SOD in orange fruits during the late stage of storage, consequently inhibiting the accumulation of malondialdehyde (MDA) and maintaining cell membrane integrity. Therefore, this coating not only has similar effect to the traditional preservative in maintaining fruit quality and delaying quality senescence, but also possesses edible safety and environment-friendly characteristics, suggesting its promising application potential as a substitute for traditional preservatives.

Walnut kernels were sealed in polyethylene (PE) or KNY17//CPE80 (a composite material) bags for low-oxygen, high-carbon dioxide modified atmosphere packaging (MAP) and then stored at (2 ± 1) ℃ for 180 days. The control samples were packaged in PE bags under normal atmospheric conditions. Meanwhile, non-MAP nano-material packaging was also studied. Relevant quality indicators were measured periodically during the storage period to investigate the effect of different modified atmosphere packaging on the quality of walnut kernels. The results showed that nano-material packaging and low-oxygen, high-carbon dioxide PE MAP had the best preservative effect on walnut kernels, significantly inhibited the increase of peroxide value (POV) and acid value (AV) in walnut kernels and maintained the good appearance of walnut kernels. Moreover, the POV, AV and carbonyl group value of amber walnuts from raw walnut kernels with both pre-storage treatments were significantly lower than those from the control group as demonstrated by high temperature accelerated storage tests.

Black beef were storaged under 0-4℃、7-11℃,this research studied the dynamic characteristics of black beef under different temperature every 10 days, the quality changes including sensory,pH values,moisture content, color,texture,bacterial count,coliform number,to get the quality and safety features of low-temperature black beef. The results showed:it is recommended that their sensory quality was declining,pH values was little declining; mei’hao black beef ’moisture content was increased and gao’jin’was contrary,the color of both samples showed a similar trend,two kinds of black beef were the opposite changes which may be related to the moisture content,the number of colony-forming units grew more slowly,but it was not exceeded standards.The lower temperature (0-4℃) was more conducive to maintain the stability and safety of low-temperature black beef.

Fresh water caltrop (Trapa acornis Nakano) fruits are very perishable and susceptible to browning, thus resulting in a short shelf life. In this study, fresh water caltrop fruits were coated with chitosan solutions at concentrations of 0.0, 1.0 g/100 mL and 2.0 g/100 mL, respectively, and stored at (4 ± 1 )℃ and relative humidity of (90 ± 2)% for 15 days. Fresh weight loss, and the contents of vitamin C, total phenolics, total soluble sugar, sucrose, reducing sugar, total soluble solid and malondialdehyde (MDA), as well as the activities of polyphenol oxidase (PPO), ascorbate peroxidase (APX), superoxide dismutase (SOD) and catalase (CAT) were determined periodically to evaluate the effect of chitosan coating on the quality and physiology of fresh water caltrop fruits during storage. The results showed that chitosan coating at concentrations of 1.0 g/100 mL and 2.0 g/100 mL significantly reduced the fresh weight loss of fruits, and retarded the decline of vitamin C, total phenolics, total soluble sugars, sucrose, reducing sugar and total soluble solid contents when compared with the control, thus maintaining fruit quality. Furthermore, chitosan coating at both concentrations also inhibited PPO activity, delayed the increase of APX and SOD activities, and decreased MDA accumulation when compared with the control. In conclusion, chitosan coating is effective in preserving the quality properties, delaying the senescence and prolonging the shelf life of water caltrop fruits.

Mango fruits were subjected to hydrocooling treatment at 0 ℃ and then stored at 13 ℃ and relative humidity (RH) of 85%－90%. The results indicated that hydrocooling treatment retarded the decrease of fruit firmness, delayed weight loss and reduced yellow index, and also maintained the soluble solid content (SSC). However, hydrocooling treatment could result in an increase in the occurrence of storage diseases.

In this study, the preparation process parameters of health yogurt with banana resistant starch as a functional ingredient were explored. The effects of banana powder addition and storage time on yogurt quality were studied. The results showed that the optimal levels of banana powder and banana essence were 3% and 0.05‰, respectively. The optimal fermentation conditions were fermentation for 4.0 h at 40 ℃ and an inoculum amount of 4%. The prepared yoghurt showed a shelf life of 7 d at 4 ℃, had a high nutritional value, and retained a high level of resistant starch. These investigations provide a theoretical basis for further studies on healthy yogurt with good properties and dietary fiber.

Black raspberry juice and fresh milk were mainly used to develop a black raspberry milk beverage. An L9(34) orthogonal array design was employed to optimize its formulation, and its composite stabilizer was optimized using simplex-centroid design. The results showed that the combination of 8% black raspberry juice, 35% fresh milk and 6% sucrose resulted in the best product quality with a sensory evaluation score of 92. The best stability was obtained using a composite stabilizer composed of 0.129% CMC, 0.037% xanthan gum and 0.084% guar gum, resulting in a minimum precipitation rate of 2.77%.

In this study, the preparation process parameters of health yogurt with banana resistant starch as a functional ingredient were explored. The effects of banana powder addition and storage time on yogurt quality were studied. The results showed that the optimal levels of banana powder and banana essence were 3% and 0.05‰, respectively. The optimal fermentation conditions were fermentation for 4.0 h at 40 ℃ and an inoculum amount of 4%. The prepared yoghurt showed a shelf life of 7 d at 4 ℃, had a high nutritional value, and retained a high level of resistant starch. These investigations provide a theoretical basis for further studies on healthy yogurt with good properties and dietary fiber.

Low-temperature healthy sea intestine-pork sausages maintaining the traditional flavor and pork sausages and having improved nutritional and health functions were made mainly from sea intestine and pork. The optimal sea intestine-to-pork ratio in the formula was 15:75, and the pork used was composed of fat and lean at a mixing ratio of 3:7. Meanwhile, natural flavor additives were added to prepare sausages with quite delicious taste and abundant ingredients beneficial to human health.