Effect of starter cultures on the quality of Suan yu, a Chinese traditional fermented freshwater fish

Abstract

Summary The generation of volatile compounds of four starter cultures composed of isolated microorganisms from traditional Suan yu was investigated. The cultures included two pure starters (PS1: Lactobacillus plantarum 120 and PS2: Pediococcus pentosaceus 220) and two mixed starters (MS1: L. plantarum 120, Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31 at 1:1:1; MS2: P. pentosaceus 220, S. xylosus 135 and S. cerevisiae 31 at 1:1:1). Naturally fermented Suan yu was used as control. The volatile compounds were collected from the headspace of the samples by Solid‐phase microextraction and analysed by gas chromatography–mass spectrometry. The type and total content of volatile compounds in the mixed‐starter‐fermented fish were higher than those of the pure‐starter‐fermented samples and control. A total of seventy nine and eighty volatile compounds were detected in Suan yu fermented with MS1 and MS2, respectively, with ethanol as the predominant compound and hexanal, ethyl acetate, 3‐methylbutanol, 3‐hydroxy‐2‐butanone, hexanoic acid ethyl ester and 2,3‐butanedione as the other compounds. Furthermore, the sensorial acceptance of the different products with mixed starter cultures seemed to improve the quality of Suan yu products.

Lipase Addition Promoted the Growth of Proteus and the Formation of Volatile Compounds in Suanzhayu, a Traditional Fermented Fish Product

“…The pH dropped rapidly in the first 7 d and slowed to 4.4 at the end of the fermentation. According to Zeng's study, Suanzhayu with a pH lower than 4.6 is generally considered as mature [12,13]; thus, both of the groups almost went on the same fermentation process. Additionally, the lactic acid content gradually increased from 2.7 to 7.6 and 6.8 mg/kg in U0 and U100 groups, respectively.…”

Exploring the Fungal Community and Its Correlation with the Physicochemical Properties of Chinese Traditional Fermented Fish (Suanyu)

“…As shown in Table 2 , the pH values of the Suanyu samples ranged between 4.30 and 5.50. The pH values of Suanyu samples made using inoculation fermentation ranged from 4.09 to 4.48 [ 18 , 22 ], which were lower than those of the Suanyu samples in this study. The average pH values of the G and H groups were 4.85 and 5.08, respectively, which were similar to that of the sample made using spontaneous fermentation in the study by Zeng et al [ 22 ].…”

Genotypic diversity of bacteria and yeasts isolated from Tibetan kefir

“…Literatures indicate that intraspecies strain diversity exists within some microbial species; different strains belong to one species exhibit different technology characteristics (Lucena et al, 2010;Bautista-Gallego et al, 2013). The final quality of fermented food relies heavily on the technology characteristics of microbial strains in the starter cultures (Zeng et al, 2016;Guarrasi et al, 2017). Application of the (GTG) 5 -REP-PCR technology in this study enabled the microbial isolates from Tibetan kefir classified to species level (Gao et al, 2015) could be further classified to strain level for genotype distinguishment, which is not only the necessary grouping procedure for the selection of I 2 III 19 3566 , 3291, 3230, 2657, 3291, 3230, , 2188, 3291, 3230, , 1904, 3291, 3230, , 1551, 3291, 3230, , 1485, 3291, 3230, , 1377 II IV 17 3566, 3291, 3230, 2657, 2188, 1904, 1551, 1485, 1377ZLGX15-17 III V 16 3230, 2657, 1904, 1551, 1485, 1377ZLGX20-24, 30-31 IV VI 12 3566, 3291, 3230, 2657, 2188, 1904, 1551, 1485 International Journal of Food Science and Technology 2018 strain with outstanding technology characteristic from the strains of each genotype in our further next study, but also is the precondition for strains of all different genotypes can be included in the 'direct vat set starter of Tibetan kefir' in our further ultimate application study.…”