Study On The Preparation And Characteristics Of Probiotic-rich Miscellaneous Bean Powder

In this study,miscellaneous beans were used as raw materials to prepare probiotic-rich miscellaneous bean powder by spray drying technology.First,the Plackett-Bunnan design and response surface test were used to determine the best preparation process for probiotic-rich mung bean powder.The universal applicability of the process in red beans,chickpeas,cowpeas,peas and tiger skin kidney beans was verified(the number of viable cells exceeded 10~6cfu/g).Three typical miscellaneous beans(mung beans,chickpeas and tiger-skin kidney beans)were selected for comparative study,through comparative analysis of miscellaneous bean powder without probiotics,miscellaneous bean powder with probiotics(not fermented),and miscellaneous bean powder with probiotics(fermented).The effect of fermentation on the physicochemical,structural and functional characteristics of probiotic-rich bean powder was explored.In addition,the best protective agent and shelf-life prediction of miscellaneous bean powder were studied,and the best dissolution conditions of miscellaneous bean powder were discussed.The results are as follows:1.Screening and optimization of the process conditions of probiotic-rich miscellaneous bean powderTaking the number of viable bacteria as the response value,based on the Plackett-Bunnan design test,it was found that the main factors affecting the number of viable probiotic bacteria in mung bean powder were soaking temperature,homogenization pressure and inlet temperature.Based on the response surface test,the levels of three factors were optimized.The best preparation process condition of probiotic-rich mung bean powder was:soaking temperature was 50?,homogenization pressure was 200bar,and inlet temperature was 115?.Through the verification test,it was found that the preparation process can satisfy the preparation of red bean powder,chickpea powder,cowpea powder,pea powder and tiger skin kidney bean powder rich in probiotics,the number of viable probiotic bacteria in the final miscellaneous bean powder exceeded10~6cfu/g.2.The physicochemical and structural characteristics of probiotic-rich miscellaneous bean powderThe wettability,dispersibility and dissolution rate of the probiotic-rich miscellaneous bean powder was improved.The main reason was that fermentation can reduce the particle size of the miscellaneous bean powder.Scanning electron microscopy results also confirmed that the particle size of the probiotic-rich miscellaneous bean powder was reduced.The angle of repose and sliding angle decreased,indicating that the fluidity became better.The dynamic rheology confirmed that the probiotic-rich miscellaneous bean powder had typical weak gel rheological characteristic,and the static rheology found that the probiotic-rich miscellaneous bean powder was a pseudoplastic fluid and the system was unstable.Therefore,the fluidity was good,which helped to improve the dispersibility and solubility.There had no effect on the main nutrients in probiotic-rich miscellaneous bean powder.Fourier infrared spectroscopy analysis showed that the secondary structure of the protein in miscellaneous bean powder was different,and most of the structure would not change due to fermentation.3.The functional characteristics of probiotic-rich miscellaneous bean powderThe probiotic-rich miscellaneous bean powder can slow down the increase in blood sugar,and its mechanism of action was:the content of total phenolic compounds,total flavonoids and proanthocyanidins were increased in probiotic-rich miscellaneous bean powder,thereby promoting the improvement of total antioxidant capacity and enhancing the inhibitory effect on the increase of blood sugar.The ability to inhibit?-amylase and?-glucosidase activity was enhanced.The ratio of resistant starch to the total starch content was increased,thereby reducing the starch hydrolysis index and lowering the estimated glycemic index.In addition,it can also reduce the content of anti-nutritional factors in probiotic-rich miscellaneous bean powder,reduce the content of stachyose and raffinose,and its oil retention and emulsification were improved.4.Study on shelf-life prediction and dissolution characteristics of probiotic-rich miscellaneous bean powderThe best way to protect the probiotics in the probiotic-rich miscellaneous bean powder was to add 1%trehalose.The shelf life of the product was predicted by the Arrhenius model.It was found that in order to maintain the vitality of Lactobacillus fermentum FL-0616 in the miscellaneous bean powder during the one-year shelf life,it should be ensured that the series of miscellaneous bean powder was stored below 10?.The best dissolution condition for probiotic-rich miscellaneous bean powder was:dissolution temperature was 40?,dissolution time was 90s,and dilution ratio was 1:12.