氯化钾部分替代食盐对减钠虾酱中风味化合物的影响OA

To investigate the effects of partial substitution of NaCl with KCl on the flavor compounds in reduced-sodium shrimp paste,four groups of shrimp paste were fermented with 18%NaCl as the control group(S18-0)and with KCl substituting 3%,6%,and 9%of NaCl(S15-3,S12-6,and S9-9),respectively,during which the contents of amino acid nitrogen(AAN)and total volatile basic nitrogen(TVB-N)were monitored.After fermentation,sensory evaluation of the shrimp paste was conducted,and with unfermented shrimp paste as the blank control,the contents of free amino acids,flavor nucleotides,free fatty acids,and volatile flavor compounds were determined,and key differential volatile flavor compounds were screened out based on multivariate statistical analysis.The results showed that at the end of fermentation,the group S12-6 exhibited the highest AAN content,and the TVB-N content of the group S9-9 was much higher than that of the other groups,yet still far below the safety limit.The group S9-9 presented a weak aroma with a pungent ammonia smell,whereas the overall acceptability of the groups S18-0,S15-3,and S12-6 showed no significant differences.With the increase in KCl substitution level,the contents of free amino acids,flavor nucleotides,and free fatty acids all exhibited a trend of first increasing and then decreasing,reaching their maximum values in the group S12-6.Glutamic acid was the amino acid contributing most to the taste of shrimp paste,and guanosine monophosphate and inosine monophosphate were the main umami-contributing substances.A total of 59 volatile flavor compounds were identified in the shrimp paste,and principal component analysis(PCA)showed that the volatile flavor compound profiles of the groups S18-0,S15-3,and S12-6 were similar,which differed greatly from that of the group S9-9.Based on a relative odor activity value(ROAV)>1 and a variable importance in projection(VIP)>1,eight key differential volatile flavor compounds were screened out,and the relative contents of compounds associated with off-flavors,such as 2,3-pentanedione,were relatively more abundant in the group S9-9.In summary,fermentation with 12%NaCl and 6%KCl enabled the production of flavorful reduced-sodium shrimp paste at the laboratory scale.This study provided technical support and theoretical foundations for the development of reduced-sodium shrimp paste.