Research And Development Of Bag Solid Beverage Using Defatted Wheat Germ

Defatted wheat germ, rich in proteins, was derived from the byproduct of wheat germ during the processes of flour production and wheat germ oil production. It has not been better utilization for a long time. And it is great waste of good food resources. A solid beverage with both good taste and nutritional quality got from defatted wheat germ (DWG) was developed and studied in this paper. The development of wheat germ solid beverage was a new way of comprehensive utilization of DWG, which might provide a basis of enhancing DWG value for both theory and practice.The main results are as follows: the producing process of DWG solid beverage was: DWG hydrolysis got by using protease, centrifuging, vacuum concentration and spray drying, with the generated powder as a solid beverage nutritional ingredient and the DWG was heated to outlet the flavor ingredients. At last, the hydrolyzed defatted wheat germ (DWGH) and heated defatted wheat germ were blended and filled into the filter bag.In this paper, defatted wheat germ was hydrolyzed by alcalase, flavor-enzyme, GC710, neutrase and papain respectively to produce nutrition powders of DWG solid beverage. The results suggested that alcalase was the best protease to produce nutrition powder for DWG solid beverage and the best degree of hydrolysis (DH) by alcalase was 6%. Under these conditions, there were 8.21% of soluble nitrogen in DWGH and the DPPH? scavenging capacity of DWGH was 50.25%. The average molecular weight of the hydrolyzed powder was 1,245 Da, with 89.67% of molecular weight distribution of DWGH below 1,200 Da. And the DWGH showed a better balance of amino acids, with high lysine concentration.DWG was treated by the extrusion, microwave, roasted, steam-roasted, respectively. The result showed that steam-roasted was the best DWG heating method to ensure the good flavor of the solid beverage, followed by microwave and roasted by oven and the worst was extrusion and roasted in pan. The optimum parameters of steam-roasted were that DWG was steamed for 4 min, followed by being crushed to 20 to 60 meshes and roasted for 5 min.The best mixing ratio of heated DWG to DWGH was 3:1. The best infusing temperature was 80℃. And the best infusing times was twice as well as optimal infusing for 6 min. The weight of solids and soluble Nitrogen in solid beverage after infusing twice accounts for 77.65% and 78.50%, respectively. The aroma of solid beverage consisted of 38 kinds of substances, with 39.12% of glipizide, pyrrole and pyridine, 9.77% of ketones, 6.55% of aldehydes, 6.25% of furans and 6.77% of hydrocarbon substances.