The Research On Processing Technology And Immunity Function Of Composite Probiotics

Probiotics have become the ideal alternatives of antibiotic, with a seriesadvantages of high efficiency, no tolerance and no residual. Survivability of probioticsduring storage become the key of estimating the quality of the product. most of theprobiotics products was consist by single strain of bacterial, for example,Lactobacillus, Yeast, Bacillus subtilis. The function of improve the immune activityof body was effected by a variety of probiotics, so the objective of the study wasmixed different kinds of probiotics to gain a product of composite probiotics.The financial support to the Researh Support(20130206048NY) from JilinProvinical Science and Technology Department.The lactic acid bacteria and yeastwas isolated from kefir grains, compound with Bacillus subtilis to obtain thecomposite probiotics. Using a method of spray drying can reduce the cost ofproduction, and promote the industrialization of probiotics products. The results of thestudy indicated that adding the products in the feed of the broilers, can improvegrowth performance and immune function, which providing a theoretical basis for thenew composite probiotics product.(1) By the study on the effect of freeze-drying protectants on the survival rate ofprobiotics, the single-factor-experiment results showed: the optimum single-factorfreeze-drying protectants of probiotics were14.00%skim milk,4.00%trehalose,1.50%glucerol. Then the formulation of protectants was optimized by means ofresponse surface methodology, the optimum formula was determined as:14.17%skimmilk,4.00%trehalose,1.65%glycerol, and the survival rate can reach89.91%. Theenumeration of probiotics was1.37×1012cfu/g, the lactic acid bacteria was5.60×1011cfu/g, the yeast was3.90×1011cfu/g, and the bacillus subtilis was4.20×1011cfu/g.(2) By using low-temperature spray drying tower, the optimum spray dryingconditions were screened out with the single-factor experiment and orthogonalexperiment. The inlet temperature was135oC, the outlet temperature was55oC, the concentration of the suspension was30%. The enumeration of probiotics was1.25×1012cfu/g, the moisture content was3.60%, can demand the standard of storage.Comparision between powders by spray and freeze drying, the results showed thatboth of the two methods can reach the quality standards, but the method of spraydrying may provide an effective way of the industrial produce of compositeprobiotics.(3) The results of the simulated digestion experiment showed that the productmay effectively protected probiotics from gastric juice. The technology of the studymay improve the tolerance of bile and acid of the probiotics. By the study of theshelf-life test, results showed that the counts of probiotics were decreased during thesix-months storage. But it remained above109cfu/g after6months.(4) By determined the gain of weight, the ratio of feed, the immune organ index,lymphocyte ANAE+and T target, and the red blood cell garland rate of the broilers,the results showed that composite probiotics can improve the growth and immunityfunction of the broilers.