关键词: 腊肉；复合发酵剂；二次接种发酵；挥发性风味成分；气相色谱-质谱法

Abstract: This study was carried out in order to explore the effect of second inoculation time on the volatile flavor components of fermented dry-cured meat. Fermented dry-cured meat samples were prepared by sequential inoculation of Staphylococcus xylosus MT, a dominant strain in traditional Longxi bacon, followed by a 1:1 mixture of Lactobacillus plantarum ZR and Leuconostoc mesenteroides CM, also dominant strains in traditional Longxi bacon. The second inoculation was performed on day 6 (F-6), 10 (F-10) or 14 (F-14) of fermentation. Besides, naturally fermented meat was prepared as a control. The volatile flavor components of fermented dry-cured meat were analyzed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) combined with relative odor activity value (ROAV) and principal component analysis (PCA). The results showed that 38, 51, 57, and 43 volatile flavor compounds were detected in the control, F-6, F-10 and F-14 samples, respectively. The number and amount of volatile flavor components in the inoculated groups were higher than those in the control group. The largest number of volatile flavor components were found in the F-10 group, and those with ROAV values greater than 0.1 accounted for a high proportion of the total. Nonanal, benzaldehyde, (E,E)-2,4-decadienal, ethyl caproate, ethyl octanoate and 1-octene-3-ol were the key flavor compounds in the inoculated groups. Meanwhile, the sensory evaluation results indicated that F-10 had the best flavor and the highest score. The findings revealed that sequentially inoculated fermentations could significantly increase the number and amount of volatile flavor substances in fermented dry-cured meat (P < 0.05), and that F-10 treatment was more favorable for the formation of the flavor, which provides a theoretical reference for the production of fermented dry-cured meat by inoculated fermentation.

Key words: fermented dry-cured meat; mixed starter cultures; second inoculated fermentation; volatile flavor compounds; gas chromatography-mass spectrometry