Sugar cane juice and starch fermenting process for producing yeast

Abstract

The sugar cane juice and starch fermenting process for producing yeast includes: squeezing sugar cane and clarifying to obtain sugar cane juice containing sugar in 11-17 %, setting the sugar cane juice into fermenter, introducing sterilized nitrogen source and phosphorus source, inoculating yeast seed liquid in 5-20 vol%, ventilating and stirring, and culturing. The process utilizes both sugar cane juice and starch as carbon source and energy source separately, and thus has high cell density, high yeast yield and high yeast quality. In addition, the process has the circulation of partial waste water and less pollutant draining.

Description

technical field [0001] The invention relates to biotechnology, in particular to a method for fermenting sugarcane juice and starch to produce yeast. technical background [0002] At present, the main raw material for yeast production in my country is waste molasses, a by-product of the sugar industry. There are mainly the following problems in the production of yeast using waste molasses: 1. During the sugar production process using sugarcane or beet raw materials, part of the sugar is converted into coke at high temperature Sugar pigments, or react with amino acids to produce Maillard pigments, and phenolic pigments, etc., not only cause the loss of fermentable sugar, but also these molasses pigments can also inhibit the growth of microorganisms such as yeast, greatly reducing the fermentation yield; 2. Sugarcane molasses is used as raw material, and about 10-30m 3 COD Cr Up to 50,000-100,000mg / L, and chroma of 3,000-10,000 fermentation stock solution separation wastewater...

AI Technical Summary

Problems solved by technology

[0002] At present, the main raw material for yeast production in my country is waste molasses, a by-product of the sugar industry. There are mainly the following problems in the production of yeast using waste molasses: 1. During the sugar production process using sugarcane or beet raw materials, part of the sugar is converted into coke at high temperature Sugar pigments, or react with amino acids to produce Maillard pigments, and phenolic pigments, etc., not only cause the loss of fermentable sugar, but also these molasses pigments can also inhibit the growth of microorganisms such as yeast, greatly reducing the fermentation yield; 2. Sugarcane molasses is used as raw material, and about 10-30m 3 COD Cr Up to 50,000-100,000mg / L, and chroma of 3,000-10,000 fermentation stock solution separation wastewater, and COD Cr 20-40m of washing and separation wastewater up to 10000-20000mg / L 3 , In addition, there are pollutants such as molasses pretreatment waste sediment

It is estimated that the wastewater discharged by a dry yeast factory with an annual output of 10,000 tons is equivalent to the pollution load of domestic sewage discharged from a small city with a population of 120,000, and the wastewater treatment is difficult and expensive, which not only greatly increases the production cost of yeast, but also currently In addition to using the concentration method, there is no other practical and feasible discharge treatment technology up to the standard, and the concentration method not only consumes a lot of energy, but also the equipment is prone to fouling and clogging, and there are still many problems to be solved

As a result, the wastewater discharged by most yeast manufacturers has not reached the standard discharge or even seriously exceeded the standard. The pollution problem has become a bottleneck restricting the sustainable development of yeast production enterprises.