Study On The Application And Resistant Starch Of Finger Millet

Finger millet is a kind of coarse cereals,which rich in dietary fiber,polyphenols,sulfur-containing amino acids,vitamin B family,calcium,iron and zinc.It has hypoglycemic,antioxidant,anticancer,antibacterial and other physiological effects.In this study,finger millet was added to rice and wheat products respectively to study its effects on the sensory properties,texture properties,nutritional components,antioxidant and anti-digestive properties of rice noodles and bread.In addition,finger millet resistant starch(RS3)was prepared to further study the anti-digestion mechanism of finger millet,so as to provide basis for the development of hypoglycemic products.The main research contents and results are as follows:(1)Effects of part replacement of rice by finger millet(FM)on cooking quality,sensory properties,texture,antioxidant activity and in vitro digestion of composite rice noodles(CRN)were investigated.A 20%blend of FM with rice was selected best used in the rice noodle formulation on basis of sensory evaluation.Rice noodles thus formulated showed low breaking rate(13.33%)and cooking loss rates(14.60%),high content of protein(5.58%),dietary fiber(2.64%),calcium(67.47 mg/100 g),potassium(67.31%mg/100 g),magnesium(24.72 mg/100 g)and phosphorus(99.35 mg/100 g).What’s more,increasing the FM content in rice noodles resulted in progressing antioxidative activity,as well as in increasing classes and content of phenolic compounds.Moreover,RS content in that latter case was 16.22-fold higher than in control.Overall,this study demonstrates that FM can effectively improve the nutritional value and taste of rice noodles,in addition to strengthening their anti-digestibility.(2)With the wheat bread as the control,finger millet bread was prepared by using finger millet flour with particle sizes of 60,100 and 200 mesh instead of 20%wheat flour.Its quality,sensory,nutritional,antioxidant and in vitro digestion characteristics were studied.The results showed the particle size of finger millet flour had a significant effect on the color,specific volume,texture,sensory and RS content of bread.Compared with wheat bread,although the specific volume of the composite bread prepared with 100 mesh finger millet powder decreased by 25.46%,its chewability(170.30 g)was higher,and it contained more crude fiber(2.5%),calcium(74.3 mg/100g)and polyphenols(34.90 μg/g),and its DPPH·scavenging ability and RS content were increased by two times.(3)The resistant starch(RS3)of finger millet was prepared by enzymatic hydrolysis,ultrasonic method and ultrasonic-autoclave method,respectively.The results showed that the yield of RS3 prepared by ultrasonic autoclave method was the highest.Then,the structural characteristics,in vitro digestion characteristics and physicochemical properties of RS3 prepared by ultrasonic-autoclave method were further studied.X-ray diffraction and scanning electron microscope showed that ultrasonic and pressure heat treatment made the starch re-polymerize to form a compact structure,and the crystal structure changed from A-type to B-type polycrystalline.The in vitro digestion data showed that,compared with corn RS3,finger millet RS3 had stronger anti-digestion ability.Further comparison of the digestion of finger millet starch and corn starch showed that finger millet starch indeed had higher content of RS,indicating that finger millet had obvious hypoglycemic effect,which could be attributed to the existence of its high content of resistant starch.Compared with corn RS3,finger millet RS3 has better solubility,freeze-thaw stability,anticoagulation and thermal stability,but lower swelling.It is suitable to be added to frozen,fried and baked foods to develop hypoglycemic products.The results can provide reference for the application of resistant starch and the development of hypoglycemic products.