Kaili Red sour soup: Correlations in composition/microbial metabolism and flavor profile during post-fermentation

Food Chem. 2024 Mar 1:435:137602. doi: 10.1016/j.foodchem.2023.137602. Epub 2023 Sep 26.

Abstract

Flavor and chemical changes with microbial succession during Red-Sour-Soup (RSS) post-fermentation were urgent to be revealed for quality control. RSS post-fermentation could be divided into three stages according to acidity, nutrients exhausting and total colony counts, without coliform bacteria growth nor nitrite peak was observed. Lactobacillus acetotolerans induced over 50 % increase of lactic acid, finally conducing to the lactic acid-dominated sour taste of RSS. The volatile compounds totally increased by 25.70 % in chili sauce and 32.58 % in tomato sauce (p < 0.05). In early-/middle-stage (pH > 3.5), alcohols and short-chain fatty acids increased, and butyric acid with unpleasant odor became the maximum flavor contributor. Nevertheless, in late-stage (pH < 3.5), with the reduction of alcohols and fatty acids, esters, 2-nonanone and terpenoids with pleasant flavors increased by Clavispora lusitaniae, Pichia, Cladosporium delicatulum and Rozellomycota sp.. In conclusion, the post-fermentation, especially L. acetotolerans metabolism and aciduric fungal esterification were essential for RSS characteristic flavor formation.

Keywords: Aciduric microbial; Butyrate; Chili pepper; Esterification; Fungal fermentation; Lactate; Lactobacillus acetotolerans; Tomato.

MeSH terms

  • Fermentation
  • Food*
  • Lactic Acid
  • Pichia
  • Taste*

Substances

  • Lactic Acid