Studies On Process Optimization And Moisture Migration Control Of Frozen Pizza Bread

This paper studied the processing characteristics of wheat flour, pizza bread production process conditions, and also studied controlling of moisture migration by adding water-retaining agent during frozen storage of pizza bread.The basic elements of the main raw material wheat flour were analyzed:moisture12.96%, protein10.09%, fat1.68%, carbohydrate74.53%and ash0.73%.In the study of pizza bread technology of pizza bread, Identify the best basic recipe for pizza bread:add water60%, yeast1.2%, salt1.7%, sugar5%and the results show that the best process conditions of pizza bread was fermentation temperature of38℃. fermentation time60min, baking temperature of210℃, baking for10min.Using hardness, moisture content as targets, the effects of different water retention agent on the moisture migration of pizza bread were studied. Through single factor and the distribution experiment,the results showed that the hardness of pizza bread which adding with gelatin and xanthan gum, gelatin and sodium alginate rises significantly lower than the control group, when gelatin and sodium alginate total amount was less than0.20%, the moisture content also fall slowly during frozen storage.In order to understand the physico-chemical properties of pizza bread during frozen storage, in particular the role of water in this process, it is necessary to investigate changes in the states of water over a wider spectrum. The three-component model was found to well represent the states of water in the frozen pizza bread by NMR. The results showed that T21is about6to8ms, T22between45to55ms, and these two states water incised in the frozen storage time, T23about between150-300ms the amount of T23state water of frozen pizza bread was reduced, these changes in T22and T21the corresponding intensities of protons were complicated, suggesting a dynamic structural transform of macromolecules and microscopic migration of moisture in the staling pizza bread. When the amount of compound with add gelatin and sodium alginate were0.10%and0.05%, shows that this formula helps to inhibit moisture redistribution, can improve the water-holding capacity of the pizza crust, control moisture migration in the pizza bread.Using SEM confirmed that the compound additive gelatin (0.10%) and sodium alginate (0.05%) to add in the frozen pizza bread. It can suppress frozen ice for the destruction of the crust of starch granules. And also can control the pizza bread of moisture migration better. The pizza bread quality was improved during storage period.It has been detected29kinds of volatile substancesin the pizza bread by SPME-GC-MS. The amount of has changed, but kinds of volatile substances is not increase or decrease during storage, That can explain frozen storage conditions maybe keep the flavor of pizza bread. But the addition of gelatin and sodium alginate were pizza bread volatile composition effect was not significant.