Development Of Quinoa-ginger Yogurt And Its Alleviating Effects On Arsenic Toxicity

As socialism with Chinese characteristics entering a new era and the implementation of the program of "healthy China",people's demand for food has changed from "guaranteed supply" to "safety,nutrition and health".Yogurt is one of the most popular fermented dairy products in the world.It is favored by the majority of consumers because of its rich nutrients and remarkable healthcare effect.In this study,quinoa,ginger and skim milk powder were selected as raw materials to develop a functional composite yogurt,in which quinoa pulp and ginger juice were added to the recovered skimmed milk and then fermented by lactic acid bacteria compound starter.Then its quality and safety was evaluated.Furthermore,the intervention effect of the yogurt on arsenic-induced toxicity in mice was explored.The main results are as follows:(1)Optimization of solidifying yogurt containing quinoa and ginger juice.The formula of quinoa-ginger yogurt was optimized by using single-factor experimental design and response surface optimization experimental method,taking the sensory score of quinoa-ginger yogurt as the evaluation index.The optimum formula of quinoa-ginger yogurt was determined as follows: 35.60% quinoa pulp,11.60% skim milk powder,8.70% ginger juice and 7.00% table sugar.(2)Analysis of the quality and safety of quinoa-ginger yogurt.The sensory,physicochemical and microbiological indexes of yogurt produced by the optimal formula were tested according to the National Standard for Food Safety of Fermented Milk(GB19302-2010).The results showed that all the indexes were in line with the limits of the national standard.In addition,it was found that the scavenging rates of hydroxyl radical(·OH)and ABTS radical(ABTS+·)of quinoa ginger juice yogurt were higher than those of ordinary yogurt at the same concentration,and the scavenging rates of ·OH and ABTS+· of the two kinds of yogurt were proportional to the yogurt concentration.Furthermore,according to the evaluation procedure of food safety toxicology in China,a 28-days oral toxicity test on the yogurt was carried out in mice.The results showed that the body weight,water consumption and behavior of mice were not significantly abnormal after being fed with quinoa-ginger yogurt for 28 days.There were no significant changes in the main biochemical indexes in serum,and there were nosignificant changes in main organ weight and organ coefficient of mice,which indicated that quinoa-ginger yogurt had no obvious toxic effect in mice.(3)Intervention effect of quinoa-ginger yogurt on arsenic toxicity in mice.The whole animal model of chronic arsenic exposure in drinking water was established by freely drinking water containing As 10 mg/L in male ICR mice for 60 days,and 16.65 m L/ kg·BW quinoa-ginger yogurt was given to stomach(once every other day)in order to observe the effect of quinoa-ginger yogurt on organ damage of mice exposed to arsenic in drinking water.The results exhibited that the yogurt could significantly alleviate the toxic effect of chronic arsenism via drinking water in mice,showing inhibition on the increase of serum glutamic pyruvic transaminase(ALT)and glutamic oxaloacetic transaminase(AST)activity in mice induced by arsenic,and inhibition on the increase of hydrogen peroxide(H2O2)and malondialdehyde(MDA)content in liver,lung,testis and small intestine tissue induced by arsenic exposure.Moreover,increased reduced glutathione(GSH)content and total superoxide dismutase(T-SOD)activity in tissue to return to the normal level,and improved the arsenic exposure induced damage of the above tissue structure in mice,which effectively reduced the oxidative damage and structural pathological changes of tissue in mice.Taken together these results indicated that the quinoa-ginger yogurt can alleviate the toxic effect of chronic arsenic exposure from drinking water in mice and protect the physiological function and tissue structure of experimental animals.In summary,a kind of pure natural functional yogurt with unique flavor,nutrition and health care function was developed by using single-factor experimental design and response surface optimization experimental methods optimized the yogurt formula.The experimental results indicate that the yogurt is natural,safe,no side effects,and preliminary animal experiments show that the yogurt can alleviate arsenic poisoning from drinking water.In a word,the fermented yogurt mixed with quinoa and ginger not only combines a variety of nutrients and functional components of quinoa and ginger,but also enhances the deep processing value of quinoa and ginger,which has broad development prospects.