In order to achieve large-scale production of meat starter Lactobacillus pentosus, a low-cost and easy to prepare medium was determined based on the growth state of the strain. The experiment simulated the effect of MRS in classical Lactobacillus pentosus culture medium, and corn steep dry powder instead of Mrs nitrogen source could play a better role.

Lactobacillus pentosae is a kind of lactic acid bacteria, which plays an important role in fermented sausage production: it can metabolize carbohydrates to produce lactic acid, resulting in low pH value of products, thus inhibiting the growth of pathogenic bacteria and spoilage bacteria; its bacteriocin can also inhibit the common spoilage bacteria in food, such as bacillus, Staphylococcus aureus, etc; It can promote the decomposition of nitrite and reduce the possibility of nitrite formation by the interaction of residual NO2 - and diamine. Its metabolic end products also give sausage special flavor. At present, MRS medium is mainly used for the culture of Lactobacillus pentosus, which is rich in vitamins, nucleotides and other nitrogen sources. Corn steep dry powder is suitable for the growth of Lactobacillus pentosus. However, the obvious shortcomings of Mrs media limit its large-scale application. First of all, it's expensive. Secondly, phosphate in buffer system can easily change Lactobacillus from short antifreeze rod to non antifreeze fiber rod. Therefore, it is necessary to screen suitable medium for large-scale application of Lactobacillus pentosus.

In the microbial fermentation industry, the cost of fermentation medium accounts for about 30% and 6% of the total cost, while the cost of nitrogen source in MRS medium accounts for about 90% of the total cost. Therefore, cost reduction is mainly to reduce the cost of nitrogen source. Corn steep liquor is made from corn starch byproduct spray drying, its cost is low, its nutrition structure is very suitable for the growth and reproduction of lactic acid bacteria. "It is rich in soluble protein, amino acids, vitamins, inorganic salts and other proteins, with a content of about 40% (8)", and can be used as a nitrogen source for the reproduction of lactic acid bacteria. At the same time, it contains a good buffer system, which can avoid the phosphate damage to the strain in MRS medium. Corn steep dry powder medium has been successfully used in the cultivation of Bifidobacterium.

Corn pulp dry powder can reduce the use of phosphate and inorganic salt, and is more suitable for large-scale application.