Study On Processing Technology And Functional Evaluation Of Hazelnut Peptide Beverage

The C.heterophylla×C.avellana is a new cold resistant and big fruit variety bred by interspecific hybridization between Corylus avellana and Corylus heterophylla native to China,and contains rich nutrients,protein content is more than 20 %.But because protein is a macromolecular,which is not easily absorbed by the human body,and the human body can absorb easily peptides as intermediate products of protein digestion.By enzymolysis of protein,a solid beverage with hazelnut peptides as ingredient is mainly developed from the C.heterophylla×C.avellana in China,in order to provide a direction and basis for the development of hazelnut functional foods.The C.heterophylla×C.avellana collected from Tieling City,Liaoning Province were dehulled,pulverized,and degreased,and the double-enzymatic hydrolysis process of the extracted hazelnut protein was investigated and optimized.The optimal process parameters were as follows: Protease,the substrate concentration value is 2.2 %(Mass ratio),p H 7.0,the amount of enzyme added is 11.5 %,the temperature is 60 ?;the second step is alkaline protease,the amount of enzyme added is 12 %,p H is 8.5,the temperature is 55 ?,and the degree of hydrolysis is 38.85 %.Three repeated experiments were performed to obtain a hazelnut protein hydrolysate with a degree of hydrolysis of 39.67 %.The molecular weight analysis and further separation and purification of the hazelnut peptides after double enzymolysis were performed.It can be seen that most of the hydrolyzed peptides were distributed below 7.8 KDa.Six components were obtained after separation by dextran gel,and further detection combine and retain the three combined components below 10 KDa(respectively three molecular weights of 5.8 KDa-7.8 KDa,3.3 KDa-5.8 KDa,and < 3.3 KDa).The samples after lyophilization provides materials for the next activity study.The anti-oxidation test used Vc as the positive control group,and tested the anti-oxidation ability of the three components of hazelnut polypeptide at different concentrations.The results showed that the hazelnut peptide group ? and group III had a clearance rate of DPPH(1,1-diphenyl-2-trinitrophenylhydrazine)free radicals to 86.98 % and 91.32 % of Vc;the hazelnut peptide group ?,The scavenging rate of ABTS(2,2'-biazine-bis-3-ethylbenzothiazoline-6-sulfonic acid)free radicals in group ? reached 79.84 % and 97.74 % of Vc;The absorbance values of hazelnut polypeptide group ? and group ? are 0.49 and 0.81 respectively,which reached 25.52 % and 42.18 % of the total reduction capacity of Vc.Through comparison and analysis,hazelnut peptide of group ? and group ? have certain antioxidant capacity.The anti-fatigue test mainly uses the weight-bearing swimming test of mice.The anti-fatigue effect of hazelnut polypeptide drink is determined by comparing the swimming time of the mice,the blood urea nitrogen and the whole blood lactic acid content after swimming.The experimental results showed that compared with the control group,the swimming time of the high-dose group ? and group ? high-dose group were 1.74 times and 1.83 times that of the control group,respectively,and the difference was extremely significant(p < 0.01).The levels of blood urea nitrogen and whole blood lactate in the high-dose and medium-dose groups of mice were significantly reduced,and the differences were extremely significant(p < 0.01).Through comparison and analysis,the hazelnut peptides of the group ? and group ? drinking have a certain function of alleviating physical fatigue.Finally,using sensory evaluation as an indicator,the formula of hazelnut peptide drink was established as maltodextrin 17%,sucrose 13%,and sodium carboxymethyl cellulose 0.03%.After that,the hazelnut peptide drink was sterilized,and the sterilization condition was 85 ? for 10 min.The shelf-life was tested based on sensory evaluation and microbiological indicators.The results show that when stored at 4 ? and 25 ?,the shelflife is 90 days,and when stored at 37 ?,the shelf-life is 50 days..In summary,this article has optimized the enzymatic hydrolysis process of hazelnut peptides,investigated the antioxidant and anti-fatigue activities of peptides with different molecular weights,and manufacture a solid beverage with hazelnut peptide as the main functional component,provide theoretical basis and experimental reference for the development and research of hazelnut functional food.