The Study And Application On Physical And Chemical Properties Of Lotus Seed Protein

Xiantan Lotus is a water lily plant. Dried lotus seeds are mature type of Chinese food, and it is used be a used specific resources with medicine function. Xiangtan lotus cultivation is not only a long history but also with high yield and good quality. Lotus itself is an advanced nourishing food,can be Edible in fresh. Dried fruit also can be consumed. Application of lotus seed can produce many seeds with a variety of delicious and therapeutic function of health.This paper studied the best way to extract lotus'seeds protein. We used lotus' seeds as raw material and studied the liquid ratio, extraction temperature and the extraction time in extraction rate of lotus'seeds protein in the experiment. The optimal extraction was obtained as follows:the ratio of solid and liquid 1:12 (g/ml), extraction in 0.15mol/L NaCl solution at 45℃for 50 min. The extraction yield was 86.45%.The four protein components of lotus seed were obtained by Osborne fractionation and their amino acid contents was analyzed. The results showed that content of albumin in the lotus seed protein was the highest (41.58 g/100 g), following by those of globulin(26.58 g/100 g), glutelin(18.00 g/100 g)and that of prolaminet was the lowest(6.00 g/100 g). The essential amino acids in the four protein components were less or higher than that in FAO/WHO reference pattern, respectively. The values of BV and AAS in the albumin and globulin were higher than that of the pattern. Based on amino acid score (AAS)and chemical score (CS), the first restrictive amino acids of the lotus seeds protein were methionine and essential amino acid, and its essential amino acid index(EAAI) was 57.95. DSC results showed that the denaturation temperatures of albumin, globulin, glutelin and prolamin were 81.7,75.2,66.8 and 69.4℃, respectively. The protein of lotus seed is a superior resource of plant proteins.With lotus seeds'protein as raw material, the test studied optimal extraction was obtained as follows:temperature 55℃, pH 5.5, enzyme 0.16g, substrate concentration 4%, reaction time 30min.In this test, used washing desalination method to except the salt which contained in lotus seed'protein. The optimal washing method was as fowllows: use the water volume as the same as the protein volume, and then washed once just enough. The Lotus seed protein powder spray drying method of the optimum conditions is:ferment in the natural condition 20h, feed concentration 30%, inlet temperature 180℃. Through the method we could got protein purity of 87.5% of lotus protein powder. IR spectra analysis shows that Protein powder also contains small amounts of carbohydrates and lipids.