To study the oil absorption pattern of French fries, soybean oil, camellia seed oil and their blends in different proportions were used repeatedly to fry French fries for 1, 3 and 5 d consecutively, and variations in the contents of total, surface and structural oil and water content were measured during the frying process. It was found that for each used oil, the total oil content of French fries increased with frying time, while for each fresh oil it significantly increased with frying time up to 150 s and then did not change, reaching about 0.22 g/g at 240 s. The deterioration degree of frying oil greatly affected the oil content of French fries. For each deterioration level, oil viscosity increased, and the oil absorption ability of French fries became stronger with increasing frying time, as manifested by increased surface oil content for all groups. The rate of change in moisture content declined with increasing frying time up to 120 s for the repeatedly used frying oils. There was an increasing difference in the ratio total oil to moisture content with increasing frying time from 150 to 240 s, and the highest value was observed with camellia seed oil for 3 and 5 d repeated use.

In order to obtain glycosylation products with excellent antioxidant activity, a bovine serum albumin (BSA)-glucose glycosylation model was established. The contents of soluble protein and free amino groups were used as indicators of the glycosylation degree of the system at different reaction times and temperatures. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging capacity, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging capacity and reducing power assays were applied to investigate the in vitro antioxidant activity of glycosylation products. The results showed that prolonging the reaction time and improving the reaction temperature could increase the glycation degree. With increasing glycation degree, the antioxidant capacity of BSA-glucose system first increased and then decreased. The product obtained after reaction at 55 ℃ for 48 h had the strongest DPPH and ABTS cation radical scavenging capacity with half maximal inhibitory concentration (IC50) of 1.17 and 0.92 mg/mL, respectively, and the strong reducing power with a concentration required for optical density of 0.5 (ρ(OD0.5)) of and 3.25 mg/mL. In contrast, the product obtained after 12 h reaction 80 ℃ exhibited IC50 of 1.02 and 0.68 for DPPH and ABTS cation radical scavenging, respectively and ρ(OD0.5) of 3.62 mg/mL. Therefore, this study can provide useful data for controlling the formation of antioxidants in thermal food processing.

The aim of this study was to investigate the effect of probiotics on rumen and intestinal microbial abundance and metabolites, plasma lipid parameters and meat quality in Sunit lambs. Totally 12 Sunit lambs at 3 months of age were randomly divided into two groups of 6 animals each: control group (fed on a basal diet) and probiotics group (fed on the same diet supplemented with a probiotic combination at 1.50 × 109 CFU/g), and the feeding period lasted for 90 days. The results showed that the structure of rumen and intestinal microflora in the probiotics group differed from that in the control group. The abundance of rumen Bacteroidetes, Bacteroides and f-Bacteroidales-BS11-gut-group as well as intestinal f-Lachnospiraceae and Ruminococceae-UCG-002 in the probiotics group was significantly higher than that in the control group (P < 0.05) and the opposite was true for the levels of butyric acid as gastrointestinal metabolites (P < 0.05). The probiotics group exhibited a significant increase in plasma high-density lipoprotein cholesterol (HDL-C) concentration and significant decrease in plasma low-density lipoprotein cholesterol (LDL-C) concentration (P < 0.05). The pH24 and shear force of lamb meat in the probiotics group were significantly lower than those in the control group (P < 0.05), while a* value was significantly higher than that in the control group (P < 0.05). Correlation analysis showed that the abundance of rumen Bacteroidetes was positively correlated with acetic acid and propionic acid levels (P < 0.05); the abundance of intestinal Ruminococcaceae-UCG-002 was positively correlated with isobutyric acid and isovaleric acid levels (P < 0.05); the abundance of rumen Prevotella-1 was negatively correlated with plasma HDL-C (P < 0.01); the abundance of rumen of Firmicutes was negatively correlated with cooked meat percentage (P < 0.01); and the abundance of intestinal Firmicutes was positively correlated with meat a* value (P < 0.05). Overall, this study concluded that dietary supplementation of probiotics can change the gastrointestinal microfloral structure and metabolites as well as plasma lipid parameters and consequently improve meat quality.

In the present study, postharvest yellowing rice (PHY) and normal rice flours were evaluated by measuring their rheological, thermal, viscosity and structure properties and the differences in their internal structure were investigated. The results showed that a decrease in total color difference, increase in the content of amylopectin, decrease in the contents of amylopectin, protein and lipid, elevation in gelatinization temperature, and reduction in viscosity and breakdown value were found in PHY as compared to normal rice flour. The rheological properties indicated that the storage modulus and loss modulus of PHY decreased relative to the control, and the molecules were closely arranged, along with enhanced fluidity and shear resistance, and reduced thixotropic loop area, suggesting that PHY had distinct non-Newtonian fluid characteristics. There was no significant difference between the infrared spectra of PHY and normal rice except that the peak intensity of PHY at 1 047 and 1 022 cm-1 was increased when compared with normal rice, which indicated that postharvest yellowing will increase the short-range ordered structure of rice. Exploring the differences in internal structure and rheological properties between PHY and normal rice will be helpful to establish a rice yellowing early warning system and extend the application of postharvest yellowing rice.

In order to study the effect of peanut kernel baking temperature on peanut butter flavor and comprehensive quality. Peanut butter was prepared by baking fresh peanut kernels at 130, 140, 150 and 160 ℃ separately for 30 min. Headspace solid phase micro-extraction-gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile flavor components of peanut butter samples. Acid value, peroxide value, and the contents of vitamin E and sterol were detected and sensory evaluation was carried out to determine the optimal baking temperature for the production of peanut butter. The GC-MS results showed that the relative contents of aldehydes, pyrazines and furans in peanut butter prepared at a baking temperature of 130 ℃ were 32.06%, 14.35% and 10.57%, respectively, having a sweet aroma and flavor. The relative contents of aldehydes, pyrazines and furans in peanut butter prepared at a baking temperature of 140 ℃ were 21.29%, 32.27% and 13.61%, respectively, with the highest contents of 2-ethylpyrazine, 2,5-dimethylpyrazine and 2-ethyl as characteristic flavor, and the peanut butter had a rich roasted peanut-liked flavor without burning odor. The relative contents of aldehydes, pyrazines and furans in peanut butter prepared at a baking temperature of 150 ℃ were 11.74%, 31.95% and 26.58%, respectively, having an enhanced roasted peanut-liked aroma with a slight burning odor. The relative contents of aldehydes, pyrazines and furans in peanut butter prepared at a baking temperature of 160 ℃ were 3.47%, 31.93% and 29.33%, respectively, giving off a noticeable burning smell without sweet aroma and flavor. The contents of vitamin E and sterol in peanut butter changed little with the increase in baking temperature, which were 22.72–23.73 and 126.47–139.25 mg/100 g, respectively. Brightness (L*) of peanut butter gradually decreased with the increase in baking temperature, redness (a*) gradually increased, and yellowness (b*) increased first and then decreased. Acid value did not change significantly, while peroxide value increased first and then decreased. In order to improve the overall quality of peanut butter, the best baking conditions for peanut kernels should be 140 ℃ 30 min.

The aim of this study was to investigate the effect of dietary linseed supplementation on the histological profile of Longissimus dorsi muscle (LD) and meat quality of Sunit sheep. Methods: Totally 20 three-month-old sheep weighing (16.94 ± 1.29) kg with good body condition were randomly divided into control and linseed groups. The linseed group was fed the control diet with 8% replacement of concentrate by linseeds and the experiment lasted for 3 months. The results indicated that the diameter of muscle fibers and the cross-sectional areas of type I and IIB muscle fibers in the linseed group were significantly lower than those in the control group (P < 0.01), whereas the percentage number and area of various muscle fiber types were not statistically significant between both groups (P > 0.05). The linseed group demonstrated a significant increase in the relative expression of MyHCI and MyHCIIx genes (P < 0.01) and an increase in the relative expression of MyHCIIa and MyHCIIb genes (P > 0.05). Skeletal muscle from the linseed group had a statistically significant higher activity of succinate dehydrogenase (SDH) and lower activity of lactate dehydrogenase (LDH) (P < 0.01). Compared with the control group, a significant increase in pH0 (P < 0.05) and a decrease in L* value, pH24 and shearing force (P < 0.01) were observed for The linseed group. There was no significant difference in other meat quality indicators between both groups. Conclusion: The dietary linseed supplementation has a positive effect on improving the color and tenderness of meat by promote the conversion of muscle fiber from glycolytic to oxidized, decreasing the diameter and cross-sectional areas of muscle fiber.

Objective: In order to improve the digestive bioaccessibility of bamboo leaf flavonoids, this study aimed to clarify the protective effect of pectin on bamboo leaf flavonoids during simulated in vitro gastrointestinal digestion. Methods: The concentrations of isoorientin, orientin, isovitexin and vitexin from bamboo leaves at different stages of digestion in the presence and absence of pectin were determined by ultra-high performance liquid chromatography (UPLC). Results: Compared with the undigested samples, direct digestion (without pectin) significantly decrease in the concentrations of the four C-glycosylflavones (P < 0.05). Moreover, oral, gastric and intestinal digestion had different effects on the flavonoid concentrations. It was highlighted that the bioaccessibility of these flavonoids was significantly improved by pectin treatment (P < 0.05). Especially, the bioaccessibility of isovitexin and vitexin was increased by 75.1% and 80.2%, respectively. Moreover, principal component analysis and cluster analysis demonstrated different cluster tendencies for the four bamboo leaf flavonoids after treatments. Conclusion: Pectin is useful to enhance the bioaccessibility of bamboo leaf C-glycosylflavones, indicating its promising application in functional food products containing these flavonoid compounds.

Zizania latifolia has delicious taste and high nutrition value, but is perishable with a short shelf life due to the water content of over 90%. In order to extend the shelf life, a mathematical model to describe heat and mass transfer in cylindrical pieces of Zizania latifolia during vacuum cooling was developed taking into consideration both transient heat transfer and mass conservation, and using computational fluid dynamics, simulation and prediction of heat and mass transfer in Zizania latifolia were conducted. Pressure variations inside the vacuum chamber, material mass variations, and temperature distribution were also simulated and compared with the experimental data. The results indicated that the simulation results agreed with the experimental data. The deviation between simulated and experimental values for pressure, mass loss and average temperature difference between the inside and the outside was 7.4%, less than 8% and only 3.7%, respectively. The model proved to be useful to predict the change of heat and mass transfer in cylindrical pieces of vegetables during vacuum cooling, which will provide useful references to study the water migration characteristics of cylindrical pieces of vegetables under vacuum environment and improve the vacuum cooling process in the food industry.

To develop and utilize anthocyanins in purple passion fruit peel (Passiflora edulis Sims cv. Zixiang 1), anthocyanins were extracted and identified from purple passion fruit peel. The antioxidant activity of the crude extract and the purified anthocyanins and their inhibitory ability against type 2 diabetes-related enzymes were evaluated. Their in vitro bioavailability was also investigated. The results showed that the total anthocyanin content in the purified sample was (122.31 ± 1.31) mg/g. A total of 12 anthocyanins were identified, and six anthocyanins. In terms of antioxidant capacity, inhibitory effect on α-amylase and α-glucosidase and in vitro bioavailability, the purified anthocyanins were significantly superior to the crude extract.

In order to achieve slow digestion of starch and maintain the stability of postprandial blood glucose, starch-apigenin complex (SAC) was prepared by ball-milling method, and the in vitro digestibility of SAC was evaluated. Using one-factor-at-at-time method, the optimal conditions for the preparation of the complex were determined to be starch:apigenin mass ratio of 5:1 and milling time of 30 h, giving a content and percent complexation of apigenin of 71.5 mg/g and 35.7%, respectively. Characterization by scanning electron microscopy (SEM), X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis showed that the morphology of the starch granules was altered by ball-milling with some of them being ruptured, and apigenin was adhered to the starch granules and gathered together. The crystalline diffraction peaks of apigenin in SAC disappeared after ball-milling treatment, and its characteristic absorption peaks disappeared at 1 081 and 700–800 cm-1. The thermal stability of corn starch could be improved by complexation with apigenin. In vitro digestion experiments showed that SAC with mass ratio of corn starch to apigenin of 5:1 had the lowest digestion rate of 18.8% after being incubated for 5 h, indicating that the presence of apigenin increased the anti-digestibility of starch, and the higher the content of apigenin in the complex, the lower the digestion rate of starch.

Endogenous transglutaminase (TGase) is closely related to the properties of surimi gel, and irradiation may cause changes in the structure and activity of TGase. In order to investigate the effect of electron beam (EB) irradiation at different doses on its quality, TGase activity of hairtail (Trichiurus haumela) surimi was determined as well as its optimum temperature and pH, and the conformation of TGase was analyzed by Fourier transform infrared and circular dichroism spectroscopy. Moreover, changes in the gel strength and water-holding capacity of surimi gel were examined to investigate the mechanism underlying the effect of EB irradiation on the endogenous TGase and gel properties of surimi. Results showed that the activity of TGase increased first and then decreased with the increase in EB irradiation dose. Irradiation at a dose of 5 kGy significantly increased the activity of TGase, and gave the highest gel strength and water-holding capacity. The optimum pH of TGase was 8.0 for each dose group, and the optimum temperature was 40 ℃ for all dose groups except 9 kGy and control group. Furthermore, EB irradiation could transform the secondary structure of TGase, leading to the lowest contents of α-helix and β-turn, and the highest contents of β-sheet and random coil at a dose of 5 kGy. Therefore, EB irradiation can affect the secondary structure and activity of TGase in hairtail surimi, at an appropriate dose promote the transformation of α-helix and β-turn into β-sheet and random coil. In addition, it can improve the activity of TGase and consequently promote the gelation of hairtail surimi.

To explore a new technique for replacing traditional heat processing, thermosonication (TS) (at 50 ℃ and 2.7 W/mL for 1, 2 and 3 min) and heat processing (at 60 ℃ for 15 min) of wheat beer were comparatively evaluated by examining their impacts on microbial populations, colloidal haze, flavor and foam stability during 84 days of storage. The results showed that the microbiological stability of TS-treated beer was comparable with that of heat-treated sample, and the development of both aerobic bacteria and lactic acid bacteria was inhibited during storage. The main parameters (ethanol content, original gravity, pH, bitterness and viscosity) were scarcely affected by either treatment compared to control samples. However, pasteurization increased the color value. Pasteurization resulted in an increase of phenethyl alcohol and ethyl acetate concentrations and a decrease of isoamyl acetate concentration in the beer compared to TS. These treatments did not affect the amounts of 4-vinylguaiacol and 4-vinylphenol in the beer. Meanwhile, TS-treated beer had higher colloidal haze and foam stability than pasteurized beer. Dynamic light scattering analysis showed that TS treatment resulted in a smaller and more uniform particle size, thus having a positive effect on the desired beer haze stability during storage.

To explore the mechanism behind the effect of different freezing methods on the water-holding capacity of frozen pork, immersion-frozen and air-frozen pork were subjected to determination of freezing loss, thawing loss, cooking loss, pH, water distribution and protein degradation and their microstructure were observed. Chilled samples were considered as control. Results showed that the freezing loss of 3-day and 3-month immersion-frozen samples was significantly lower than that of their respective air-frozen counterparts (P < 0.05). The pH value of immersion-frozen samples did not significantly change with increasing freezing time (P > 0.05), and the immobilized water was transformed into bound and free water, with a significant increase being observed in the proportion of bound water (P < 0.05). On the other hand, the pH value of air-frozen samples decreased significantly (P < 0.05), and the immobilized water and bound water were all transformed into free water, with a significant increase being observed in the proportion of free water (P < 0.01). The intermuscular space decreased in immersion-frozen samples as compared to air-frozen samples. Overall, these results could explain why the water-holding capacity of immersion-frozen samples was superior to that of air-frozen samples, which will provide technical support for the optimization of pork freezing.

In the present study, fresh sweet potato leaves were by four different drying methods of hot air drying, vacuum freeze drying, microwave vacuum drying and far infrared drying. Low field nuclear magnetic resonance and drying curves were used to evaluate changes in moisture content, state and distribution as well as mass and heat transfer in sweet potato leaves during drying. Besides, comprehensive quality assessment of the dried products was conducted with respect to micromorphology, color and rehydration performance. Results showed that the water in sweet potato leaves was classified into two types: bound water T21 (0.06–13.67 ms) and free water T22 (13.67–580.52 ms). Microwave vacuum drying showed the fastest drying speed, reducing the moisture content from 84.42% to 9.97% in 0.75 h. Both mass and heat transfer occurred from the inside to the outside of sweet potato leaves, and the porous structure in the surface of sweet potato leaves exhibited decreased degree of wrinkling after drying, with no significant change being observed in the microstructure. The microwave vacuum dried product had the highest levels of brightness and green color without obvious yellowing. In addition, its rehydration capacity (6.69 ± 0.29) was equivalent to that of the dried samples obtained by vacuum freezing drying and hot air drying, but significantly higher than that from far infrared drying (4.92 ± 0.73) (P < 0.05).

In this study, the effect of dynamic high pressure microfluidization (DHPM) under different pressure conditions on basic structural characteristics, rheological properties and solid morphology of red kidney bean polysaccharide (RKBP), prepared by sequential water extraction and alcohol precipitation, was systematically studied. The results showed that DHPM treatment could increase the saccharide content of RKBP. The viscosity and molecular mass of RKBP decreased significantly with the increase in pressure. The monosaccharide composition and solid morphology of RKBP were affected by DHPM treatment, while it had limited effects on the thermal stability, infrared spectrum and 1H nuclear magnetic resonance spectrum. The effect of DHPM treatment on saccharide content and monosaccharide composition may be associated with the precipitation of impurities and the rupturing of branched chains. In summary, this study can provide a theoretical basis for the future processing of RKBP beverage.

Ultrasonic treatment was used to promote the formation of complexes between red bean protein and lutein, and their structural and functional properties were measured and analyzed to explore the relationship between improvements in the functional properties and structural changes. The maximum binding rate between red bean protein and lutein was obtained by ultrasonic treatment at 240 W for 10 min. Thermal properties and Fourier transform infrared spectroscopy indicated the formation of red bean protein-lutein complexes, which reduced the surface hydrophobicity and free sulfhydryl content. Appropriate ultrasonic treatment reversed the decrease in both parameters and decreased the peak temperature and thermal enthalpy. The α-helix structure of the complexes was transformed into random coils under ultrasonic treatment, thus resulting in a looser and disordered structure, which might be related to the improved functional properties of the protein. Combination with lutein increased the solubility of red bean protein, but did not significantly change its emulsifying capacity, emulsion stability, foaming capacity and foam stability (P > 0.05). Ultrasonic treatment further increased the solubility of the complexes, and enhanced their emulsifying capacity, emulsion stability and foaming capacity. The most significant improvement was achieved by ultrasonic treatment at 240 W for 10 min. However, ultrasonic treatment had no significant effect on the foam stability of the complexes.

This paper was aimed to investigate the effect of sucrose control on the microstructure and quality of explosion-puffed yellow peach slices. Fresh-cut yellow peach slices were impregnated separately in sucrose solutions at concentrations of 0, 5%, 15%, 25% and 35% before explosion puffing drying. The microporosity, cell wall composition and structure, color, puffing degree, textural characteristics (hardness, brittleness, shearing force, puncturing force, and crushing force), and moisture absorption rate of dried peach slices were analyzed. With the increase in sucrose concentration, the microporosity decreased, and the wall thickness and uniformity of micropores increased. A lower concentration of sucrose could prevent the thermal degradation of pectin, hemicellulose and cellulose in the cell wall of peach slices during explosion puffing drying, thus reinforcing the strength of the cell wall. The contents of pectin and hemicellulose reached their highest values at sucrose concentrations of 15% and 25%. Moreover, results of infrared spectroscopy indicated the characteristic absorption peaks of aromatic ring, α-glycosidic bond and β-glycosidic bond were observed at both sucrose concentrations and the characteristic absorption peaks of O–H bond stretching vibration and C–O stretching vibration were significantly reduced at sucrose concentration of 35%. The color and puffing degree of dried samples were improved at a lower sucrose concentration. With the increase in sucrose concentration, the tissue structure strength was enhanced, the cells were enriched, and the hardness, brittleness, crushing force, shearing force, and puncturing force were increased, all reaching their maximum values at sucrose concentration of 25%. Sucrose impregnation at 5% and 15% had little effect on the hygroscopicity of dried yellow peach slices, but when the concentration was above 25%, it declined. Therefore, sucrose can effectively improve the quality of explosion-puffing-dried yellow peach slices. This study reveals a correlation between the quality of dried peach slices and the microporous structure as well as the cell wall composition, which provides a theoretical basis for improving the quality of dried peach products.

Oxidized mung bean starch was prepared with sodium hypochlorite as an oxidant and 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) as a catalyst under ultrasonic treatment and its structure and properties were analyzed. Using one-factor-at-a-time method, the optimal preparation conditions were determined to be molar ratio between oxidant and glucose units in starch 1.5:1, and pH 8.5–9.0. Subsequently, the effect of ultrasonic treatment on the structure and properties of oxidized starch prepared using the optimized conditions was studied. The results showed that at an ultrasonic frequency was 25 kHz, the highest degree of oxidation and the smallest particle size were obtained. The results of scanning electron microscopy (SEM) showed that the original starch granules were smooth and intact, while the oxidized starch granules were broken into smaller particles with pores and dents being observed on the surface. Fourier transform infrared spectra showed that obvious carboxyl absorption peaks occurred in the range of 1 613–1 637 cm-1, indicating that the starch was successfully oxidized. The X-ray diffraction results showed that the diffraction peaks of the starch did not change in shape and position after oxidization, suggesting no change in the starch crystal type. However, the starch properties such as viscosity, particle size, charge, solubility and transmittance changed greatly after oxidation, which will be beneficial to the application of mung bean starch.

The traditional seafood soup ‘Fotiaoqiang’ was processed into broth powders by separately using ultrasonic spray-freeze drying (USFD), vacuum freeze drying (FD) and spray drying (SD), and we compared the physicochemical properties and microstructure of the 3 powders. The results showed that the USFD powder had low water content (4.79%), small bulk density (102 mg/mL), small particle size (23.11 μm in average), and good solubility. This powder existed mostly in the form of regular spherical particles with smooth surfaces, good uniformity, controllable size and high porosity, which facilitates the diffusion of moisture from the interior to the exterior of the particles. The FD powder presented various states, such as needle type and flat type. The SD powder particles mostly exhibited an oblate spherical shape. The USFD powder scored 8.8 points in sensory score for flavor, which was more in line with the flavor standard of undried traditional broth. Solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS) was used to investigate the retention of volatile compounds during the drying process. The results showed that 39 volatile compounds were detected in the USFD sample, including 7 alcohols, 7 aldehydes, 1 ketone, 4 esters, 8 heterocyclics and 12 alkanes. Therefore, USFD could better preserve the overall flavor of the soup.

Irradiation technology was used to assist the grafting reaction between soybean protein isolate (SPI) and maltose (M) to improve the freeze-thaw stability of SPI emulsion. The effects of SPI concentration, m(SPI)/m(M) ratio, and irradiation dose on the grafting degree, browning degree and creaming index of modified products were studied. It was found that under the conditions: SPI concentration of 4%, m(SPI)/m(M) ratio of 4:1 and radiation dose of 7.5 kGy, the creaming index of modified SPI was decreased by 23.58%, 29.9% and 31.2%, respectively, after 1, 2 and 3 freeze-thaw cycles when compared with intact SPI. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) confirmed the grafting reaction between SPI and maltose. The oil release rate of the modified SPI emulsion after freezing and thawing was significantly improved when compared with SPI emulsion. Optical microscopy observation also confirmed that the optimized SPI microstructure was more stable. This study suggested that irradiation could enhance the grafting reaction to improve the freeze-thaw stability of SPI emulsion, which will provide a new integrative protein modification approach.

This study aimed to clarity the drying characteristics of ‘Xiushui Huahong’ sweet orange peel and determine a suitable drying temperature for its quality control during hot air drying. A kinetic model to describe the relationship between moisture ratio and drying time at different hot air temperatures (50, 60, 70, 80 and 90 ℃). Meanwhile, the effect of different drying temperatures on the dried product quality in terms of appearance, antioxidant capacity and the contents of flavonoids and contents of volatile flavor compounds was evaluated. The drying process involved three stages, acceleration, maintenance and deceleration. The drying rate distinctly increased as the drying temperature increased, and the data fitting result showed that the Page model could accurately describe the drying process at different hot air temperatures. Sweet orange peel dried at 50 ℃ maintained the original color and shape to the greatest extent. The contents of total flavonoids and hesperidin were the highest in the sample dried at 60 ℃, while the product dried at 90 ℃ showed stronger antioxidant capacity. Moreover, 24 volatile flavor compounds were detected in the five dried samples, 11 of which were found in each of the samples dried at 50, 60 and 70 ℃, 15 for 80 ℃, and 19 for 90 ℃. D-limonene was the most abundant volatile flavor compound in all five samples. These samples differed in their quality. Hence, drying temperature should be chosen according to actual requirements, and drying at 60 and 90 ℃ are suitable for higher contents of flavonoids and volatile flavor compounds, respectively.

In this study, fresh intact shiitake mushrooms (Lentinus edodes) were used to investigate effects of three drying methods (three-stage microwave vacuum freeze drying (TS-MVFD), freeze drying (FD), and hot air drying (HAD) on drying characteristics, nutrient composition and microstructure of dried mushrooms and sensory characteristics of rehydrated mushrooms determined by quantitative scale analysis. The results showed that TS-MVFD, FD and HAD took 5, 14 and 8 hours to dehydrate mushrooms to a moisture content of less than 13%, respectively. After 120 min of rehydration, the rehydration rate of TS-MVFD-dried mushrooms (7.1) was significantly higher than that of FD (6.0) and HAD (4.4) dried samples. The rehydration coefficient (91.40%), cap color, content of total sugar (60.21 g/100 g), crude polysaccharide (7.41 g/100 g) and free amino acid (3.44 g/100 g) of the TS-MVFD dried mushroom were no significant difference when compared with FD dried mushroom. The microstructure of TS-MVFD dried samples was similar to that of FD dried samples, except for slightly larger micropore diameter. The cross-sectional structure of HAD dried samples was stacked with the cell wall collapsing seriously. After rehydration and cooking, the flavor and taste of TS-MVFD dried mushroom samples were significantly better than those of HAD and FD dried products. Therefore, we believe that TS-MVFD will become a popular drying method for shiitake mushrooms.

Whole egg liquid was dried by double-frequency (28 kHz + 28 kHz) ultrasonic vacuum drying. The effects of drying temperature, ultrasonic power, and vacuum degree on the drying characteristics of whole egg liquid was investigated. Also, the effect of ultrasonic power on the cavitation yield was explored by measuring the amount of iodine released. A mathematical model for the drying process was established. The results showed that the drying rate increased with increasing drying temperature, but the drying temperature should not be too high. Increasing the ultrasonic power and the vacuum degree was conducive to increasing the drying rate. The results of iodine release showed that increasing the ultrasonic power effectively improved the ultrasonic enhancement effect. The effective moisture diffusion coefficient was positively correlated with the drying temperature, ultrasonic power and vacuum degree. The calculated activation energy of dual-frequency ultrasonic vacuum drying was 9.76 kJ/mol, and the energy consumption for drying was low. The Page model could better reflect the dual-frequency ultrasonic vacuum drying process of whole egg liquid. The results from this study provide a theoretical basis for the study of dual-frequency ultrasonic vacuum drying.

This study explored the effects of different processing methods (pan fixation and oven drying, microwave fixation and oven drying, and vacuum freeze drying) on the contents of water extracts, tea polyphenols, free amino acids, catechins and alkaloids and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity in tea manufactured from the fresh flowers of Camellia sinensis cv. Huangjingui. Results indicated that the contents of tea polyphenols, free amino acids, epigallocatechin, epicatechin, epigallocatechin gallate, epicatechin gallate and methyl epicatechin gallate in freeze-dried samples were significantly higher than those in samples prepared by two other methods (P < 0.05), and the content of gallic acid was the lowest among these three samples. However, no significant difference in the contents of water extracts, theogallin, and caffeine was seen among all samples (P > 0.05). Vacuum freeze drying was most beneficial for maintaining tea polyphenols, imparting the strongest DPPH radical scavenging capacity to the tea, followed in decreasing order by microwave fixation and oven drying, and pan firing and oven drying. Sensory evaluation revealed that tea samples prepared by pan fixation and oven drying, and microwave fixation and oven drying had typical corn-like flavor due to thermal dehydration. Both products tasted numbing and astringent, and the freeze-dried product had the strongest astringent taste. The different processing methods produced different sensory flavors. To sum up, tea plant flowers can be developed into a functional drinks.

Objective: The purpose of this study was to investigate the effect of carnosic?acid on free fatty acid (FFA)-induced lipid accumulation in HepG2 cells. Methods: Lipid accumulation in the cells was induced by a blend of oleic acid and palmitic acid at a molar ratio of 2:1. The cells were treated with the fatty acid blend (1 mmol/L) alone or in combination with different concentrations of carnosic acid (15 and 20 μmol/L) as well as 20 μmol/L carnosic acid plus the adenosine 5’-monophosphate activated protein kinase (AMPK) inhibitor Compound C (2 μmol/L) for 24 h. The intracellular lipid content, cell activity, the contents of triglyceride (TG) and total cholesterol (TC), the mRNA expression of genes associated with lipid metabolism and the protein expression of phosphorylated AMPK (p-AMPK) were detected to evaluate the mechanism of action of carnosic acid in lowering lipid accumulation. Results: The fatty acid blend alone and combined with carnosic acid at the concentration of 15, 20 μmol/L had no effect on cell activity. The results of oil red O staining showed that compared to the normal control group, treatment cells with the FFAs for 24 h significantly increased lipid content inside the cells. Meanwhile, upon treatment with the FFAs, the contents of intracellular TC and TG and the expression of lipid anabolism-related genes were increased, and the expression of lipid catabolism-related genes was decreased (P < 0.05). The results of oil red O staining showed that compared to the FFA-induced model group, carnosic?acid reduced intracellular lipid content. Moreover, carnosic?acid remarkably lowered the contents of TC and TG, down-regulated the expression of lipid synthesis-related genes, and up-regulated the expression of lipid oxidation-related genes and the protein expression of p-AMPK (P < 0.05). The AMPK inhibitor had no effect on cell activity, but significantly reversed the lipid-lowering effect of carnosic acid (P < 0.05). Conclusion: Carnosic acid can reduce FFA-induced lipid accumulation in HepG2 cells by regulating the transcriptional level of lipid metabolism-related genes and the expression of p-AMPK.

Objective: To explore the effect of probiotic intervention frequency and cycle on blood lipids in hyperlipidemic rats. Methods: A rat model of hyperlipidemia was established through feeding a high fat diet for 4 consecutive weeks, and two intervention groups were designed by using the probiotic Lactobacillus plantarum (Lp) 67 combined with intermittent fasting, a dietary strategy for treating obese people: intragastric administration with an Lp 67 suspension of 108 CFU/mL 5 times weekly plus physiological saline for the remaining 2 days, and administration with the same suspension every other day weekly plus physiological saline for the remaining days. Body mass was weighed during the intervention period and visceral organ indexes after 4, 6, and 8 weeks of intervention and the serum levels of total cholesterol, total triglyceride, high-density liptein cholesterol and low-density liptein cholesterol were measured. The two intervention groups were compared with the 7-day continuous intervention, control and model groups in terms of all these parameters. Results: Compared with the model group, all three intervention treatments could effectively control blood lipids in rats, and there were significant differences among these intervention groups (P＜0.05). In general, Lp 67 intervention 5 times a week for 6 consecutive weeks was the most effective in improving the blood lipid profile. Conclusion: The frequency and cycle of probiotic intervention have significant effects on improving blood lipids in hyperlipidemic rats.

Acer truncatum is a tree species unique to China. Its seeds contain abundant unsaturated fatty acids and multiple nutritional components. The aim of this study was to explore the effects of Acer truncatum seeds on the composition of the intestinal flora in mice and the inhibition of harmful bacteria. Eight-week-old Kunming mice were selected and fed 1.5 g of Acer truncatum seeds every day. After continuous feeding for two weeks, rectal feces were collected for high-throughput sequencing analysis and body mass recorded every day over the entire period. The α-diversity of the intestinal flora did not significantly differ between the experimental and control groups. In the β-diversity analysis, significant separation was found between the two groups (P < 0.05). Compared with the control group, the relative abundance of Firmicutes in the experimental group was increased whereas the relative abundance of Bacteroidetes was decreased. The relative abundance ratio between Firmicutes and Bacteroides was higher in the experimental group than that in the control group (P = 0.063). By linear discriminant analysis effect size analysis, it was found that the relative abundance of Staphylococcus and Acinetobacter was significantly lower in the experimental group, indicating that Acer truncatum seeds can inhibit the proliferation of harmful bacteria. In summary, Acer truncatum seeds can affect the structure and composition of the mouse intestinal flora and inhibit opportunistic pathogens.

In order to explore the protective effect of betulinic acid (BA) on T-2 toxin-induced intestinal oxidative damage, 60 healthy male mice were randomly divided into 6 equal groups: control, T-2 toxin, low-, medium- and high-dose BA (0.25, 0.5 and 1 mg/kg mb) plus T-2, and vitamin E plus T-2. After BA was administered for 14 days, the levels of immunoglobulin (Ig)M, IgG, and diamine oxidase (DAO) in serum were detected by enzyme-linked immunosorbent assay, the activities of catalase (CAT) and glutathione peroxidase (GSH-Px), and the contents of malondialdehyde (MDA) and glutathione (GSH) in the duodenum, jejunum and ileum were determined. Morphological changes in the jejunum were observed by hematoxylin-eosin (H & E) staining. The results showed that BA enhanced the levels of IgG and IgM, and reduced the activity of DAO in the serum. Meanwhile, it alleviated the decrease of CAT and GSH-Px activities caused by T-2 toxin in the intestine, increased GSH content, and decreased MDA content. Therefore, BA has a protective effect on intestinal oxidative damage induced by T-2 toxin in mice by increasing humoral immunity function, improving intestinal mucosal barrier function and enhancing intestinal antioxidant capacity.

In order to study the application of Nα-lauroyl-L-arginate ethylester (LAE) in the preservation of green bell pepper, compound preservatives containing LAE, sodium methylparaben and chitosan were formulated and optimized, and its preservation effect on green bell pepper was evaluated by determining the percentage of marketable fruit, decay index, mass loss rate, firmness, and the contents of ascorbic acid and chlorophyll. The results showed that the optimized formulation consisted of 700 μg/mL LAE, 100 μg/mL sodium methylparaben and 10 mg/mL chitosan. The compound preservative increased the percentage of marketable fruit, and decreased decay index and the loss of ascorbic acid and chlorophyll, thereby having a significant effect on preserving the quality of green bell pepper during postharvest storage.

In order to extend the shelf life of ginger and obtain a composite coating film with excellent antibacterial and preservative properties, composite coatings of chitosan (CS) and konjac glucomannan (KGM) were prepared by casting method, and modified by gingerin and in situ synthesized nano-SiOx. The composite coatings were characterized by scanning electronic microscopy, X-Ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) and their physicochemical properties were measured. The influence of the microstructure and physiochemical properties of the composite coatings on their preservation effect on ginger was explored. The results showed that after the addition of gingerin, the elongation at break of the composite coating was increased from 30.70% to 34.81% (P < 0.05), and tensile strength from 17.97 to 24.41 MPa (P < 0.05). While O2, CO2 and light transmittance did not change significantly (P > 0.05), water vapor transmittance was significantly reduced (P < 0.05). After subsequent addition of in situ synthesized nano-silicon based oxide (SiOx), the elongation at break of the composite coating film was increased to 38.82%, and tensile strength to 28.72 MPa (P < 0.05). Both O2 and CO2 transmittance increased significantly (P < 0.05), and light transmittance decreased slightly, whereas water vapor transmission rate did not change significantly (P > 0.05). KGM/CS composite coatings reduced mass loss, the contents of total phenolic compounds and flavonoids in ginger rhizomes during storage. Meanwhile, KGM/CS inhibited the decrease of soluble sugar, and extended the shelf-life. The composite coatings co-modified by gingerin and in situ synthesized nano-SiOx had better preservation properties as compared to either modifier alone.

Different post-harvest pre-cooling methods can influence the incidence of decay in cherry fruits, mainly due to the development of fungal community on the fruit surface. The composition and diversity of fungal community on the surface of Red Agate cherry fruit subjected to different pre-cooling treatments were analyzed during subsequent cold storage for up to 30 days, with focus on the changing trend of the dominant microbes. The internal transcribed spacer (ITS) sequence was determined by high throughput sequencing. The results showed that compared with cold air cooling, treatment with unozonated or ozonated ice water reduced the abundance and alpha diversity of the fungal microbiome during the storage period. The initial dominant fungal composition was similar in the three pre-cooling groups, including Aureobasidium pullulans, Pleosporales (one operational taxonomic unit (OTU)), Alternaria sp. (4 OTUs) and Davidiellaceae (3 OTUs). Both ice water treatments reduced the proportion of initial pathogenic fungi and increased the proportion of biocontrol fungi (Aureobasidium pullulans). During storage, the dominant fungi in each group developed. On the 30th day, Davidiellaceae (3 OTUs) became the dominant fungus in cold air treated samples. In unozonated ice water treated samples, Aureobasidium pullulans developed into the dominant fungus; however, the proportion of Pleosporales (1 OTU), Alternaria sp. (4 OTUs) and Davidiellaceae (3 OTUs) and Davidiella tassiana increased to 16.28%, 8.23%, 8.40% and 8.96%, respectively, which may cause spoilage on the surface of cherry fruit. Pleosporales was the dominant fungus in the ozonated ice water treatment group, and Alternaria (4 OTUs) accounted for 14.26% of the total fungi. These results revealed the effects of pre-cooling methods on the fugal community of Red Agate cherry fruit during post-harvest cold storage, which will provide fundamental data for the choice of pre-cooling methods and the application of other anti-fungal technologies.

Resistant starch is a new type of dietary fiber that cannot be digested or absorbed in the healthy human small intestine, but be partially or entirely fermented by bacteria in the large intestine to produce short-chain fatty acids and lactic acid as well as small amounts of gases. In recent years, resistant starch has attracted extensive attention from researchers in the fields of food science and nutrition due to its special structure and intestinal flora-regulating function. This paper mainly reviews the recent advances in research on the structural properties and intestinal flora-regulating function of resistant starch. The apparent structures, crystal structures and molecular structures of different types of resistant starch are compared. The prebiotic effect and intestinal flora-regulating function are described. Furthermore, the effects of the structural characteristics of resistant starch on its intestinal flora-regulating function are discussed. This review can provide a theoretical basis and scientific guidance for the development of resistant starch with specific structural properties to regulate the intestinal flora.

Cold plasma is a new non-thermal processing technology that has been applied in many fields of the food industry. Reactive nitrogen species produced by cold plasma can increase the content of nitrite when used to treat meat products, thus replacing the direct addition of nitrite in the production process. In this article, the mechanism of action and application of cold plasma as a nitrite substitute in meat products, and a comparison between cold plasma and other substitutes of its type. Moreover, future application directions of cold plasma are presented.

As the major protein in meat products, myofibrillar protein has a decisive effect on the quality of meat products, while excessive oxidation of myofibrillar protein will destroy the quality of meat products. The unique structural characteristics of polyphenols determine their unique antioxidant and bacteriostatic effects, which are widely used to inhibit the oxidation of myofibrillar protein and slow down the deterioration of meat products due to their natural non-toxicity. In this article, the interaction mechanism between polyphenols and myofibrillar protein is reviewed, with respect to non-covalent interactions such as hydrophobic interaction and hydrogen bonding, and amino-quinone and sulfhydryl-quinone covalent interactions. The effects of temperature, pH and ionic strength on the interaction between polyphenols and myofibrillar protein are discussed. In addition, future research directions are presented, aiming to provide a basis for further exploring the application of the interaction between polyphenols and myofibrillar protein in the field of foods.

Exercise-induced fatigue is a common physiological phenomenon caused by continuous overloaded exercise. The three main proposed mechanisms underlying exercise-induced fatigue include energy depletion, accumulation of metabolites and induction of oxidative stress. In this paper, we summarize the anti-fatigue bioactive compounds recently discovered in foods and their application as an ingredient in anti-fatigue products. This review is expected to provide new regulatory targets and research ideas for screening for safe and effective anti-fatigue bioactive compounds and offer a theoretical basis for developing novel anti-fatigue products.

Capsanthin is a carotenoid compound extracted from mature red chili peppers. It is widely used as a food and feed additive because of bright color and high safety. Capsanthin, a polar lipid-soluble substance, has bioavailability better than that of β-carotene. Besides being a colorant, capsanthin has good antioxidant capacity. It can remove excess active oxygen species in the body and participate in the regulation of signal transduction pathways related to active oxygen species, therefore alleviating oxidative stress-induced damage to body tissues and important cellular components such as deoxyribonucleic acid, lipids and proteins and exerting a wide range of biological effects. Previous studies have found that capsanthin can regulate lipid metabolism in the body, modulate immune responses, has anti-cancer and anti-radiation effects, enhance learning ability in the elderly, and especially reduce the incidence of certain cardiovascular diseases, cancers and other chronic diseases. In this article, the advances made in understanding the bioavailability, physiological functions and mechanisms of action of capsanthin in recent years are reviewed, in order to provide a reference for studying the functional properties of capsanthin.

Chinese Baijiu is a characteristic and tradition of the Chinese nation. There is a wide variety of Baijiu types with distinct styles. An important aspect of studies on Baijiu modernization is to deeply explore and clarify the difference in the quality and style of various types of Baijiu. The quality and style of Baijiu are mainly determined by a variety of micro components that are rich in Baijiu, including organic acids, esters, alcohols, aldehydes, pyrazines, terpenes, nucleosides, lipopeptides and other substances. Many of them are beneficial to Baijiu flavor and human health, but we need to face up to the low contents of beneficial micro components and the existence of harmful substances. There are many methods available to improve the contents of beneficial micro components and the quality of Baijiu, such as using functional microorganisms and strengthening the starter culture Daqu. This paper reviews the micro components in Chinese Baijiu and summarizes recent progress in research on the major micro components. Meanwhile, new perspectives for future studies are presented, aiming at providing a reference for research in this field.

Gelatin and polysaccharide gel are two kinds of macromolecular hydrophilic colloids that are widely used in the food industry. But gelatin colloids have insufficient gel network stability and poor thermal stability, and their application is restricted by religious factors. Polysaccharide gels are characterized by insufficient mechanical strength and poor water vapor barrier properties. Gelatin and polysaccharide can interact with each other non-covalently or covalently, resulting in surface selective patch bonding, emptying effect, co-gelation and other phenomena and consequently changing gel properties. By adjusting the pH, mixing ratio, temperature and other conditions that affect the structural formation and improve the gel properties of composite gels, different types of composite gel systems with unique properties can be obtained and used to further prepare nano/micro particles, hydrogels, films, lotions and foams. In this article, the existing problems on polysaccharide and gelatin gelation, the interaction mechanism between them and consequent changes in gel properties, and the external conditions that regulate composite gel properties are reviewed, aiming to provide a theoretical basis for wider application of polysaccharide-gelatin composite gels in the food industry.

Essential oils are volatile compounds extracted from the flowers, leaves, rhizome, and stems of plants; and are composed of secondary metabolites such as terpenes, phenols, alcohols and aldehydes. Essential oils are widely applied in food, medicine and other fields because of their broad-spectrum antibacterial activity. In recent years, the antibacterial mechanisms of essential oils and their components against pathogenic microorganisms are mainly discussed. These studies have demonstrated that essential oils and their components may have multiple targets for inhibiting pathogenic microorganisms, including cell wall, cell membrane and DNA. In this article, the antibacterial mechanisms of plant essential oils and their components against pathogenic microorganisms are reviewed, which can provide the basis for future research and applications of essential oils from plants.

Freezing is a common preservation method used in the storage and transportation of fresh meat, but freezing, thawing and repeated freezing and thawing will accelerate the oxidation of both lipids and proteins in meat, and further affect the quality of meat in terms of color, tenderness and water-holding capacity. This paper reviews the effects of freezing, thawing and repeated freezing-thawing on the quality of raw meat, and the underlying mechanism. Meanwhile, the emerging freezing and thawing technologies are also summarized. We anticipate that?this review will guidance China’s meat industries in the selection of freezing and thawing technologies, and also provide a theoretical guidance and research direction for the quality control of frozen products and the development of new freezing and thawing technologies.

Thinned fruits are a plant resource that can be utilized to produce with high-added-value products. Previous studies have shown that thinned fruits are rich in polyphenols, polysaccharides, amino acids and other bioactive components with significant antioxidant and physiological activities. This paper reviews the bioactive components, functional properties and applications of thinned fruits, which will improve the understanding of its important value, and provide a guidance and reference for the effective utilization and industrial application of thinned fruits.

With the rapid expansion of the global population and the unprecedented expansion of the middle-income population, the demand of human beings for meat products has shown an unprecedentedly rapid growth trend. Simply relying on the traditional breeding industry to meet the rapid growth of human consumption of meat products is facing increasingly severe challenges. Artificial meat is the most potential solution to the dilemma of meat production and consumption by humans. At present, artificial meat consists of two categories: one is based on plant proteins, which can simulate the appearance and taste of real meat products to the maximum extent and is also known as plain meat, plant meat, simulated meat, etc.; the other is based on biological tissue culture, which can provide real animal protein for human beings, bypassing animal feeding and is also known as cultivated meat, in vitro meat or clean meat, etc. However, as the artificial meat industry is just emerging in China, relevant terms, standards, laws and regulations are yet to be formulated, resulting in the confusion of nomenclature for terms related to artificial meat. In this article, based on literature data concerning artificial meat production technology, production process, social acceptance, and nomenclature currently adopted in China and worldwide, some suggestions on the normalization of nomenclature for terms related to artificial meat in China are proposed.

Cellulose is the most abundant natural polymer in nature. As the energy problem becomes increasingly serious nowadays, cellulose materials have got more and more attention. Recently, nanocellulose has become one of the key directions of nanotechnology research due to its excellent mechanical strength and chemical stability, as well as its light mass, wide availability, regenerability and biodegradability. Nanocellulose-based antibacterial composite materials have attracted extensive attention due to their excellent antibacterial properties and potential practicability and have high potential application value in the field of packaging materials. In this article, the characteristics of cellulose and nanocellulose and the antibacterial materials commonly used to prepare cellulose-based antibacterial composites are reviewed together with the current status of the application of nanocellulose-based antibacterial composites in food packaging.

Kombucha tea (KT) has many health benefits. The complex microbiological composition of KT makes difficult its standardized production on an industrial scale. Currently, most studies on KT focus on chemical composition analysis and health effect evaluation, or product development on a laboratory scale. There is little information available in the literature on the relationship between microorganisms derived from KT and its characteristic flavor compounds. This review summarizes the relationship between the dominant microorganisms in KT and the flavor compounds in fermented foods containing those microorganisms. Meanwhile, the dynamic changes in the flavor components in KT are discussed. The information gathered in this review is expected to provide support and evidence for selecting a suitable starter culture for KT production, ensuring the product sensory quality, developing new products with different flavors and functional properties and promoting the development of the KT industry.

In the new era, the new Regulation on the Implementation of the Food Safety Law of the People’s Republic of China establishes a series of innovative systems. They are the main highlights of this regulation, mainly reflected in implementing the “Four Strictest Requirements”, strengthening the basis for food safety risk control, implementing the principle of whole-process control principle, upholding and fulfilling the principle social co-governance in food safety, adhering to the problem-orientated approach and addressing prominent problems concerning food safety, and carrying out the principle of the rule of law in food safety governance. This regulation improves the institutionalization level of food safety governance, sets great store by combining risk governance with responsibility governance, and strengthens the rule of law in food safety governance, which marks a new trend of food safety governance modernization.