Quality Analysis And In Vitro Digestion And Fermentation Characteristics Of Children’s Nutritious Noodles Fortified With Dietary Fiber

With the improvement of economic level,the overall nutritional status of school-age children has been improved,but they are still facing health problem,e.g daily intakes of whole grains,dietary fiber(DF)and protein is far below recommended level and myopia level among children is on the rise.In order to improve children’s health status,this study prepared protein-rich coarse grain legume noodles and carotene-rich vegetable-millet noodles.Afterwards,the effects of DF supplementation(8%),i.e inulin(I),high-amylose corn starch(HACS),fructooligosaccharides(FOS),galactose oligosaccharides(GOS),β-glucan(BG),arabinogalactan(AG),arabinoxylan(AX),and xylo-oligosaccharides(XOS)on digestive and fermentation characteristics of the two noodles were evaluated by using in vitro digestion and fermentation model.This study provides the basis for the development of functional noodles rich in dietary fiber and protein for children.The main research contents and results are as follows:(1)Effects of DF supplementation on nutrient composition and sensory quality of coarse grain legume noodles and vegetable-millet noodles.The main ingredients of coarse grain legume noodles were chickpeas,quinoa and white lentils,while the main ingredients of vegetable-millet noodles were millet,pumpkin and carrot.The protein and total starch contents of the two kinds of noodles were 20.80%～22.51%vs 18.72%～21.62% and 50.65%～59.64% vs 53.18%～62.53%,respectively.Total starch content was significantly decreased by DF supplementation except HACS and GOS(limited to coarse grain legume noodles only)(p<0.05).The ash content and crude fat content in the two kinds of noodles was 1.15%～1.42% vs 1.08%～1.88%and 0.49%～0.89% vs 0.40%～0.80%,respectively;HACS and AX supplementation significantly decreased ash content of coarse grain legume noodles,while BG,AG and AX supplementation significantly decreased crude fat content(p<0.05).DF supplementation significantly decreased the ash content of vegetable-millet noodles(p<0.05),but had no significant impact on the sensory scores of the two kinds of noodles,but I significantly increased the breaking rate of coarse grain legume noodles(p<0.05),while BG and HACS significantly reduced that of vegetable-millet noodles(p<0.05).For coarse grain legume noodles,the content of amino acids contributing to umami flavor was higher than that of sweet flavor,the proportion of essential amino acids was close to the ideal protein standard,with high protein quality.(2)Effects of DF supplementation on the digestibility of protein in coarse grain legume noodles and carotenoid bioavailability in vegetable-millet noodles.The results showed that the protein hydrolysis of coarse grain legume noodles was mainly occurred in small intestine,i.e 22.79%～32.70%,and only 2.89%～5.2% in stomach.The addition of DF significantly increased the protein hydrolysis degree(p<0.05),except I and HACS.The bioaccessibility of carotenoids in vegetable-millet noodles ranged from 25.21% to 47.17%,and only the supplementation of BG and FOS had significant promoting effect(p<0.05).(3)Effects of DF supplementation on the fermentation characteristics of digested noodles.The results showed that the sugar content and p H value of noodle fermentation broth decreased rapidly from 0 to 12 h,but then were slowly from 12 to48 h The main SCFAs produced were acetic-,propionic-and butyric acids.For coarse grain legume noodles,XOS supplementation significantly decreased the sugar consumption rate of basic formula noodles,8 kinds of DF significantly promoted the p H reduction,the top 3 DFs were HACS>NI>GOS(p<0.05),and only HACS and FOS supplementation significantly increased the total SCFAs yield(p<0.05).For vegetable-millet noodles,the addition of AX significantly decreased the microbial sugar consumption rate,the addition of FOS and BG significantly decreased the p H reduction,while other DF significantly enhanced the pH decline(p<0.05).The addition of DF had no significant effect on the total SCFAs yield of vegetable-millet noodles.(4)Effects of digested children’s noodles supplemented with DF on fecal flora of healthy children.All noodles had no effects on richness of flora,and only a part of DF supplementations significantly decreased its diversity.Noodle changes microbialβ-diversity after fermentation.The relative abundance of Bacteroidetes decreased significantly,while that of Actinobacteria increased significantly(p<0.05).For coarse grain noodles,GOS supplementation significantly increased the relative abundance of Bifidobacterium and Lactobacillus,while XOS supplementation significantly increased that of Lactobacillus,but decreased Bifidobacterium(p<0.05).Meanwhile,DF supplementation significantly decreased the relative abundance of Clostridium＿sensu＿stricto＿1(except XOS),but increased that of Escherichia＿Shigella(except XOS)and Megamonas(p<0.05).For vegetable-millet noodles,all the DFs significantly decreased the relative abundance of Phascolarctobacterium but increased that of Bifidobacterium(p<0.05);Only I,GOS,AG and AX significantly increased the relative abundance of Clostridium＿sensu＿stricto＿1 and decreased that of Megamonas(p<0.05),while HACS significantly decreased Escherichia＿Shigella(p<0.05).In conclusion,all the coarse grain legume noodles and vegetable-millet noodles prepared in this study contain high protein and sensory scores.Moderate daily intake could meet children’s needs for protein,whole grain and DF,and help to increase carotenoids intake.Supplementing BG and FOS are benefit to increase protein digestibility and carotenoids bioaccessibility of the two kinds of noodles.The nondigestible carbohydrates in noodles could be effectively utilized by children’s fecal flora,change microbial structure,and reduce microbial richness and the p H value of the fermentation system,where the latter is conducive to maintaining the acidic environment of the intestinal tract.The addition of specific DF promotes the proliferation of intestinal beneficial bacteria-Bifidobacterium and Lactobacillus.The results of this study can provide data support for the development of children’s cereals rich in dietary fiber.