Study On Nutritional Complex Made From Wheat Germ And Low-cost Fish

Wheat germ contains considerable amounts of nutrients essential for human health. Low-cost fish, from aquatic product processing, has the same nutritional value as ordinary fish. Both of them have their own characteristics and advantages in nutrition and health functions, Wheat germ and low cost- fish are cheap and product enormously every year in China. However research development of conversion technology for them in food industry is still in the primary phase, and most fasten on the high value-added processing technology about extraction of functional components, and there is almost no a comprehensive nutrition product from wheat germ and low-cost fish by generally processing technology in marcket. The aim of this study is to develop a new convenience nutritional food for the older groups by low value-added and high-quality processing techniques.First, formula optimization of nutritional complex made from wheat germ and low-cost fish was studied in this paper. Amino acid score and mathematical model of linear programming were used for the optimization. The results showed the most suitable ratio of wheat germ and low-cost little yellow croaker was 4.17 to1 (dry basis). With this understanding, the amino acid composition of nutritional complex was more closed to ideal values.Second, in view of the characteristic of wheat germ and low-cost fish and the requirements for raw materials of extrusion, the 2.0% broken tea water +1.5% of theβ-CD, low-cost and almost no skim role method, were selected to remove the fishy of low-cost little yellow croaker, then centrifugal dehydration and smashed as fish paste. And then fish paste, baking powder of wheat germ,starch and other processing excipient were mixed in a certain proportion by dry basis, then dried to regulated water for processing. Potato starch was the most appropriate agent in this nutritional complex producing when considering its influence on the solubility, water absorbing capability, and viscosity of the products.The combination of quadratic regression hybrid experiment desiging and response surface analysis was introduced in the optimization of the extrusion technology. The results showed that at extrusion temperature 155-160℃, screw speed 150-160 r/min, potato starch dosage 28%-31%, and moisture content at 19%-21%, the products was of the best quality,and the gelatinization of products reached 86 percent, lipoxygenase inactivation rate >85%; when mixed with hot water (≥70℃) at 1: 5(W/W) ration, the mixture appeared mushy status with slightly wheatgerm flavor but no fishy smell.Adding 0.7%-1.2% of the hydrophilic sucrose ester in pre-extruded material, can significantly reduced the oil loss and falled hardness of extrusion product. And the nutrition complex powder had better quality when moisture content 5.50±0.50%, the addition of sucrose ester 1.0% and sieved at 100 mesh.Nutrients content analyzing results showed, if every adult or elderly person took in 50g nutrition powder daily, the nutrients content of the final product, particularly protein and iron can satisfied more than 1/6 of daily requirement, calcium and VE can satisfied more than 1/4. The taste evalution of final product is acceptable with paste evenly,a hint of wheat germ smell, no fishy flavor. With no significant rancidification of fat , and sensory and microbiological indicatoras have no deterioration under the storage condition of two months at 40℃.