Differences among Mixed Fermentation, Natural Fermentation and Inoculation Fermentation

1. Natural fermentation is a traditional fermentation method. Commonly used microorganisms are mainly yeast, Aspergillus oryzae and lactic acid bacteria.

Enzymes can be divided into natural fermentation and artificial inoculation according to their production methods.

2. Mixed fermentation is an artificially optimized mixed culture mode of two or more bacteria on the basis of in-depth study of microbial pure culture, which belongs to the category of microbial ecological engineering. For example, two-step fermentation of vitamin C and so on.

There are many types of mixed culture, such as combined mixed culture (two kinds of bacteria are cultured at the same time), sequential mixed culture (A and B are cultured successively), * * * mixed culture of immobilized cells (A and B are mixed together to make immobilized cells) and mixed mixed mixed culture of immobilized cells (A and B are made into immobilized cells respectively and then mixed).

3. The technological process of expanded culture of pure yeast is: original strain-yeast activation-primary culture (inoculation fermentation)-secondary culture-tertiary culture-distiller's grains culture.

Primary culture is the inoculation and fermentation of yeast. Inoculating activated yeast into grape juice (or wort), and sequentially carrying out secondary culture, tertiary culture and koji barrel culture. Pay attention to hygiene requirements when inoculating yeast. Grape juice (or wort) should be sterilized at high temperature or high pressure before inoculation to avoid contamination by miscellaneous bacteria. Determine the inoculation amount and temperature of activated yeast according to the process requirements.

introduce

Artificial inoculation fermentation mainly uses known microbial strains to ferment enzymes, which can be divided into single-strain fermentation and multi-strain mixed fermentation. Commonly used fermentation strains include yeast, acetic acid bacteria and lactic acid bacteria. Multi-strain co-fermentation can form a unique flavor. During the co-fermentation process, strains will interact with each other to form a mutually beneficial relationship, which is beneficial to the enzyme fermentation process.