Study On Solid State Fermentation And Storage Characteristics Of Peanut Meal

This paper is divided into three parts to study the storage and fermentation of peanut meal.(Ⅰ) Different water content of peanut meal for storage tests at different temperatures. Through the analysis of bacteria and mildew, find a safe storage moisture of peanut meal. Through the determination of fatty acid value, protein solubility, reaction the changes of nutritional value of peanut meal during storage.And points out the relationship between mildew and the nutritional index for peanut meal. The results show that:The peanut cake moisture content, storage temperature and storage time are the important factors which result in fatty acid value increasing, protein solubility reducing and population increasing. Temperature is an important factor which reduces the peanut meal safe water and makes the safe storage time shorter. In20℃storage temperature,13.51%is the safe storage moisture of peanut meal. In30℃storage temperature,12.03%is the safe storage moisture of peanut meal; Cladosporium sp., Aspergillus glaucus, Aspergillus restrictus, yellow aspergillus and Penicillium are the main molds to damage the peanut meal; the moisture content of peanut meal, storage temperature have a great impact on mold growth changes, and there are synergistic effect of them.(Ⅱ) Select the Bacillus subtilis and lactic acid bacteria which have the antibacterial effect, to study the fermentation of peanut meal. Through single factor experiment and orthogonal experiment to optimize the optimum fermentation conditions of the two bacterias. The results show that:The conditions of peanut meal in Bacillus fermentation produced the highest amount of oligopeptide are that fermentation time:24h, fermentation temperature:32.5℃, ratio of material to water:1:1, inoculums size:4x106cfu/g; The conditions of peanut meal in lactic acid bacteria fermentation produced the highest amount of oligopeptide are that fermentation time:48h, fermentation temperature:40℃, ratio of material to water:1:1.2, inoculums size:6×106cfu/g.(Ⅲ) Bacillus subtilis and lactic acid bacteria fermentation by optimal expanded fermentation of peanut meal, and together with the peanut meal before fermentation experiments were carried out to study the storage. The results showed that:The experimental group which mildewed, in the storage process, fatty acid value increased, potassium hydroxide solubility decreased. Cladosporium, Penicillium, Aspergillus restrictus, Aspergillus glaucus were the main harm fungus resulted in peanut meal mildew, Aspergillus glaucus and Aspergillus restrictus were the main harm fungus resulted in the peanut meal which fermented by Bacillus subtilis mildew. Aspergillus restrictus was the main harm fungi which resulted lactic acid bacteria fermented peanut meal mildew; the storage time of the peanut meals which fermented with Bacillus subtilis and lactic acid bacteria is longer than the peanut meal not be fermented, the peanut meal which fermented by lactic acid bacteria is the strongest to resistance mildew.