Study On The Preparation,Properties And Application Of RS3 Resistant Starch From Pea

Resistant starch?RS?is a kind of starch which cannot be digested and absorbed by the gastrointestinal tract.It is can be used in the intestinal probiotics after entering the large intestine,which is similar to the dietary fiber.It has a plurality of physiological functions which are more excellent than the dietary fiber.As a polysaccharide substance,the RS has the effects of reducing blood sugar,blood fat,cholesterol,and improving the symptoms of diabetes.It can also promote the proliferation of beneficial bacteria in the intestinal tract,reduce the cell death rate.It is a proliferation factor of the probiotics such as bifidobacteria and lactic acid bacteria.Preparing and application of the resistant starch have a wide market need and commercial value.At present,the research on resistant starch is mainly focused on several common starch crops and its products,such as corn starch,rice starch and so on.The relationship between the physical and chemical properties of the RS and its preparation method is less.In this paper,the application of resistant starch in food processing and actual production is carried out,and pea starch is used as the raw material.The optimum technological conditions of the preparation of resistant starch are investigated by means of a pressure-heating method,a microwave method,an ultrasonic method and a compound enzymolysis method.The effect of different methods on the physical and chemical properties of the adversarial starch is investigated.The discovery of resistant starch as a good prospect for functional food development.In this paper,the physical and chemical properties of the prepared resistant starch were studied by using the pea starch as the research object and the different treatment methods?the thermal method,the ultrasonic method,the microwave method,the enzyme method,etc.?and the different processing factors,while the optimum preparation process was obtained.The effect of different methods on the starch granule and its molecular structure was analyzed,and the relationship between the functional properties and the physical and chemical properties of the resistant starch was further revealed.The RS3-type resistant starch was prepared by a pressure-heating method,and the appropriate starch solution concentration,the aging temperature,the pH value and the heat-pressing temperature have a significant influence on the destruction and the recrystallization of the internal structure of the starch molecules,the primary and secondary factors affecting the yield of the resistant starch are as follows:The temperature of aging,pressing temperature,pH value,starch solution concentration and the response surface method were optimized.The optimum process for preparing the pea RS3 resistant starch was as follows:the hot pressing temperature was 119.9?,the aging temperature was 0?and the pH was 7.The physical and chemical properties of the resistant starch found that the solubility of the RS3 resistant starch was higher than that of the original starch,the degree of swelling was lower than that of the original starch,the internal molecular structure of the resistant starch changed,and the C-type crystal became the B-type crystal;the grain surface of the resistant starch was rough and the size of the resistant starch was not uniform,and it was irregular.The influence of the factors such as starch solution concentration,pH,aging temperature,microwave time and ultrasonic time on the preparation of RS3-type resistant starch was studied by the microwave and ultrasonic method,and the optimum process of RS3-type resistant starch was obtained.The concentration of the starch solution is 30%,the pH value is 7,the aging temperature is 0?,the microwave action time is 90 s,the best process of the ultrasonic method is that the concentration of the starch solution is 30%,the pH was 7,the aging temperature is0?,and the ultrasonic wave action time is 15 min.The physical and chemical properties of the samples were tested and the differences between the original starch of the pea and the microwave and the ultrasonic wave were analyzed.The results showed that the solubility of the RS3-type resistant starch was higher than that of the original pea,and the swelling degree was lower than that of the pea.The grain surface of the original starch was smooth.The RS3 resistant starch is an irregular fragment of different sizes,and the sample prepared by the microwave method is more rough than the surface of the particles of the ultrasonic sample.The effect of starch concentration,pH,aging temperature and enzyme ratio on the yield of RS3 resistant starch was studied by using the composite enzyme method.When the concentration of the starch solution was 20%,the pH was 6.0,the aging temperature was 0?,the enzyme ratio was 2:1 HCO₃-amylase:The yield of pullulanase is the highest,and the crystal structure of the starch is B+V,and the stability of the crystal structure is more stable than that of the C-type of the original starch.The survival rate and growth rate of probiotics were significantly improved by adding resistant starch as wall material,and the protective effect of resistant starch on probiotics in microcapsules was further verified by in vitro simulation experiments.The stability of microcapsules was significantly enhanced.Gastric acid tolerance test showed better tolerance and stability of microcapsules.Intestinal release test also showed that microcapsules had better intestinal release and could be used as the carrier of target drugs in intestinal tract.