Comparison of flavor changes of grass carp between brine injection and brining at 4°C and 20°C

Abstract

Grass carp is the most important freshwater fish in China, and salting is the main processing method. This study investigated the effect of brine injection on flavor of grass carp muscle compared with brining at low temperature (4°C) and room temperature (20°C) respectively. Salt content, free amino acids, nucleotides, equivalent umami concentration (EUC) and texture were evaluated as flavor indicators during salting. The results showed that brine injection groups reached equilibrium in 3 h and 5 h at 20°C and 4°C, respectively. Brining groups reached equilibrium in 5 h and 7 h at 20°C and 4°C, respectively. The equilibrium salt content was about 1.76%, and there was no significant deterioration in terms of the other indicators mentioned above by two different methods. The results of this research indicate the feasibility and the great economic potential of brine injection, and also provide the theoretical basis to promote this method in processing of aquatic products. Comparación de los cambios de sabor detectados en la carpa herbívora al ser procesada con inyección de salmuera y con salmuera a 4°C y 20°C RESUMEN

Effect of Lactobacillus plantarum and flavourzyme on protein degradation and flavor development in grass carp during fermentation

“…Table 1 presents the FAAs detected in the NF, LF, and FLF groups during the fermentation. The results showed that 17 FAAs were identified in the three fermentation groups, including sweet amino acids (tyrosine (Thr), serine (Ser), glycine (Gly), alanine (Ala), and proline (Pro)), umami amino acids (aspartic acid (Asp) and glutamic acid (Glu)), and bitter amino acids (cysteine (Cys), valine (Val), methionine (Met), isoleucine (Ile), leucine (Leu), tyrosine (Tyr), phenylalanine (Phe), histidine (His), and arginine (Arg)) ( Wu et al, 2020 ; Xiang, Xia, Fang, & Zhong, 2024 ; Xiao et al, 2021 ). Extending the fermentation time, the FAA levels in the NF, LF, and FLF groups significantly increased, whereas the Pro content displayed an initial decline, followed by an increase.…”

Effects of flavourzyme addition on protein degradation and flavor formation in grass carp during fermentation

“…As shown in Table 3, 17 FAAs were detected in two groups of fermented samples and divided into umami, sweet, and bitter amino acids. Among these amino acids, asparagine (Asp) and glutamate (Glu) are associated with umami taste; tyrosine (Thr), serine (Ser), glycine (Gly), alanine (Ala), and proline (Pro) are closely related to sweet taste; Cysteine (Cys), valine (Val), methionine (Met), isoleucine (Ile), leucine (Leu), tyrosine (Tyr), phenylalanine (Phe), histidine (His), and arginine (Arg) are associated with bitterness (Wu et al, 2020; Xiao et al, 2021). The content of most FAAs including Asp, Thr, Glu, Gly, Ala, Val, Met, Ile, Leu, Tyr, Phe, Lys, and Pro in NF and FF group samples increased dramatically as the fermentation time increased, whereas the content of Ser and Cys were increased then decreased and the content of Arg was decreased then increased.…”