Study On The Processing Technology Of Kelp Crispy Biscuit And Digestive Characters Of Starch

Laminaria japonica belongs to Phaeophyta Laminariaceae, and is also named river cabbage. It is rich in variety of active pharmacological polysaccharides such as seaweed starch, alginate, gum fucose and dietary fiber, which have hypoglycemic function. However, the lack of kelp’s deep processing technology leads to its low value. And biscuit is ordinarily regarded as a kind of high glycemic index food, which departs from the dietary and healthy consumption concept of Chinese residents and is harmful to biscuit’s market competitiveness. Therefore, the article is intended to develop the slow digestive kelp crispy biscuit. The main contents and conclusions were as follow.1. The dough texture (hardness, adhesiveness, springiness, cohesiveness) characteristics were studied in order to determine the initial formula. The results showed that with 12.50% kelp,67.50% butter,20～60 mesh of kelp powder, 20%～25% sugar, the dough exhibited a fine smooth surface, and compared with other samples, it displayed the best in plasticity and softness, moderate in hardness, adhesiveness, springiness, cohesiveness, which made oil could locked within the dough properly.2. Based on the initial formula,the effect of biscuit’s texture (hardness, adhesiveness) characteristics and sensory characteristics were studied with different additions of kelp, butter, sugar and mesh of kelp powder through single factor test, on the basis of single factor test, the addition of kelp, butter and mesh of kelp powder were selected as study factors, hardness, adhesiveness, sensory score were chosen as indexes in the three factors and three levels orthogonal experiment to determine its optimum production formula. Orthogonal test results showed that the best formula for kelp crispy biscuit is 12.50% kelp (low-gluten flour,100%),67.50% butter,60 mesh of kelp powder,25% sugar,7.5% milk,30% egg,12.5% water. The color and kelp’s aroma of biscuit were pleasant, the taste of biscuit is moderate sweet and salty, crispy and non-greasy.3. In vitro test like Eylnst mean was used to evalue digestive characters of starch. Porcine pancreatic a-amylase and glucoamylase enzyme mixture were used to imitate in-vivo environment to hydrolyze kelp crispy biscuit samples. The effect of different addition of kelp were studied by analyzing the content of three different digestible starches, the hydrolyzed curve of starch, and the prediction of biscuit’s glycemic index using a dynamics simulation equations. The results showed that with the increased addition of kelp, Rapidly Digestible Starch was reduced to 33.5%, Slowly Digestible Starch was increased to 32.3%, Resistant Starch was risen to 34.2%; the rate of balanced hydrolysis rate was slowed to 36.0%; biscuit’s glycemic index was significantly reduced from 74.6 (high-glycemic index food) to 61.9 (moderate-glycemic index food); and with the best formula of kelp crispy biscuit, that is 12.5% kelp, the biscuit’s glycemic index was 67.3, as a moderate glycemic index food. Therefore, the kelp crispy biscuit not only has unique taste, but also has nice slow starch digestion features, it is better for the obese, the old.4. The kelp crispy biscuit product was examined and the results showed that the content of water, acid value, peroxide value, microbial indicators were in line with the requirement of "GB/T 20980-2007 Biscuit" and "GB 7100-2015 National food safety standards of biscuit"; in addition, the content of Polysaccharide was up to 18.6%, glycemic index is 67.3 (moderate-glycemic index food) in the kelp crispy biscuit product, glycemic index is 74.6 (high-glycemic index food) in the control group (without addition of kelp powder biscuit). The reason is that Laminaria Polysaccharide is sticky, it can slow down the rate of digestion of starch, thus effectively reducing the glycemic index of biscuit. Finally, according to "GB/T 20980-2007 Biscuit" and "GB 7100-2015 National food safety standards of biscuit", the standards of kelp crisp biscuit product were made and the HACCP system were established. Thus, it ensured the quality and safety of kelp crisp biscuit product in enterprise processing.