Suanyu fermentation strains screening, process optimization and the effect of thermal processing methods on its...

Area of Science:

• Food Science
• Microbiology
• Fermentation Technology

Background:

• Suanyu, a traditional fermented aquatic food from South China, suffers from inconsistent quality due to natural fermentation variability.
• Environmental factors significantly impact the fermentation process and final product quality of traditional Suanyu.

Purpose of the Study:

• To screen and identify suitable microbial starters for Suanyu fermentation.
• To optimize the fermentation process for improved Suanyu quality and flavor.
• To evaluate the impact of different thermal treatments on the sensory characteristics of Suanyu.

Main Methods:

• Screening of microbial fermenters, specifically identifying Enterococcus rivorum and Enterococcus lactis.
• Optimization of a mixed starter fermentation process for Suanyu.
• Investigating the effects of natural fermentation versus mixed starter fermentation.
• Assessing the impact of thermal treatments (microwave, frying, roasting) on Suanyu flavor profiles.
• Utilizing electronic nose technology for sample discrimination.
• Conducting sensory evaluations for flavor and color assessment.

Main Results:

• Mixed starter fermentation resulted in lower TVB-N content and richer total acidity and flavor compounds compared to natural fermentation.
• Histamine content showed no significant difference between fermentation groups.
• Roasting treatment significantly increased free amino acids, organic acids, nucleotides, and key aroma components.
• Electronic nose successfully differentiated between differently treated Suanyu samples.
• Sensory evaluation indicated that roasted and fried Suanyu samples possessed more acceptable flavor and color.

Conclusions:

• The use of selected microbial starters (Enterococcus rivorum and Enterococcus lactis) and optimized fermentation processes can stabilize and enhance Suanyu quality.
• Thermal treatments, particularly roasting, significantly improve the flavor profile and sensory acceptance of Suanyu.
• This research provides a theoretical basis for the standardized production of Suanyu and the development of convenient, pre-cooked products.