Studies On Staling And Freshness Of Chinese Rolls

A traditional Chinese rolls was studied in this paper.The retrogradation of Chinese rolls and their inhibition was mainly studied. The main content is as follow: detection of the retrogradation process; selection of retrogradation indicators and detection methods; the study on the retrogradation factors of Chinese rolls; additives on Chinese rolls which inhibit the retrogradation were the main area of research.Selected Texture Analyzer, DSC, chemical and colorimeter were used to detect retrogradation process of Chinese rolls during storage. The results showed that amylopectin recrystallization was the main reason for retrogradation of Chinese rolls. The hardness value, amylopectin recrystallization enthalpy value, water-soluble starch, chromatism value and sensory value was taken as indicators of retrogradation of Chinese rolls. The results showed that there were closely correlative relationship between sensory evaluation and the hardness value, amylopectin recrystallization enthalpy value, water-soluble starch and chromatism value parameters. Analysis by synthesis, Texture Analyzer and sensory evaluation were chosen as the test method of retrogradation. Therefore, the retrogradation indicators system for Chinese rolls was determined which was base on the hardness value and sensory evaluation as the main indicators.The effects of cooling method on hardness of Chinese rolls were studied. The results showed that rapid cooling could reduce retrogradation degree of Chinese rolls better than cooling at room temperature. Under different storage temperatures, the retrogradation of Chinese rolls for2days during storage was studied. The influence of storage temperature on quality and retrogradation of Chinese rolls showed an important impact. The sensory evaluation first increases then decreases with an increasing of storage temperature. Under different heating temperature of Chinese rolls, staling experiments were studied and results showed that heating temperature is an important influencing factor on the quality of Chinese rolls. The sensory evaluation first increases then decreases with an increasing of storage temperature. High heating temperature and low heating temperature will influence the edible quality of Chinese rolls. After comprehensive analysis, this paper adopts the natural cooling and heating temperature under195℃,4℃storage.Xanthan gum, CMC, amylase and Monoglycerides resin were chosen for the anti-staling agent of Chinese rolls, optimal formula was reached through response surface analysis (RSA) method, the optimum point was found at; Xanthan gum0.142%, CMC0.402%and amylase0.0185%. Scanning electron microscopy was carried out for the research of retrogradation of Chinese rolls. The results showed that additives delayed retrogradation of starch in Chinese rolls from the microscopic view, therefore, improve the quality of the products, the shelf life of the products.