Study On Quality Improvement And Storage Characteristics Of Fried Dough Stick

Fried dough stick, is a traditional Chinese breakfast food and popular snack, featuredwith crisp outside and soft inside, suitable salty and scent, easy digestion, low costs andenjoyed by the old and young. With the speedy pace of people’s life and theindustrialization trend of traditional food, developing a fried dough stick by improving itsquality and extending its shelf which has a certain storage period at room temperature andgood taste can not only increase the sorts of modern traditional food, but also is a key pointof the development of food industry, furthermore it is a scientific problem to test thepersonnel working in the area of food science and technology. On the basis of predecessors’research, this paper focused on the study of formula and effects of non-aluminum leaveningagent, improver and storage of fried dough stick quality.First of all, the amount of sodium bicarbonate was2.5%through the single factorexperiment, and the interaction of three different acid salts was studied by response surfacemethod according to the principle of composite leavening agent. The regression equationwas obtained with specific volume and sensory scores as response value. The optimumformula of non-aluminum leavening agent was obtained as follows through verificationexperiment and comparative experiment of regression equation: Sodium bicarbonate2.5%,Gluconate delta lactone is1.72%, Sodium acid pyrophosphate0.72%, Citric acid0.28%.The quality of fried dough stick by this formula is close to that of the traditional "alumalkali salt" method and better than that of non-aluminum leavening agent made by Angelcompany which provides a new thought and method for the development of non-aluminumleavening agent.Second, the quality improver was studied. This experiment selected three emulsifiers tostudy their effects on quality of fried dough stick. In the single factor experiments, withsensory score, specific volume and hardness as evaluation index, the optimum addingamount of three emulsifiers is: monoglycerides,0.6%, sugar ester,0.2%DATEM,0.5%.Select L9(34) orthogonal experiment to optimize three single factors, with sensory score,specific volume and hardness of5days storage as evaluation index, it is concluded that thebest formula is: monoglycerides,0.6%, sugar ester,0.2%DATEM0.5%. At this point, thescore of sensory evaluation and hardness was respectively4.67mL/g and528.614g.Finally, the storage characteristic of fried dough stick was studied. By adding differentamount of glycerol to food, study its influence on the shelf life of fried dough stick, thefollowing conclusions were obtained:1. with the increase of glycerol content, sensory quality gradually decreases. However, a certain amount (5%) of glycerol contributes to theimprovement of the specific volume;2. with the increase of glycerol content, the watercontent of fried dough stick was gradually increasing, water activity was graduallydecreasing, and when the adding amount was15%, water activity was0.864, scarcemicroorganism grew at this level;3. a certain amount (5%~10%) of glycerol helps delay thehardening rate of food, and this may be correlated with increasing the specific volume;4.the microorganism grew more slowly with the gradual increase of the glycerol which maybe affected by the reason that glycerol affected the water activity in food. Considering allfactors mentioned above, the amount of glycerol was confirmed between5%and10%which helped the storage characteristic of fried dough stick in order to extend the shelf lifeof food.