储藏过程中馒头理化指标的变化

Changes during the storage process of the physicochemical indexes of steamed bread

研究了馒头在储藏过程中各理化指标的变化。测定了储藏过程中馒头微生物数量、馒头白度值及硬度值、馒头水分活度、糊化度及其微观结构的变化,结果显示,馒头在储藏过程中,馒头的水分活度保持较高水平,其霉菌数量先平缓上升,后急剧增加。馒头的白度值略有下降,但基本保持不变。馒头的硬度值逐渐增大,而馒头的糊化度则呈现逐渐下降的趋势。馒头储藏过程中,淀粉与面筋蛋白的结合逐渐松散,淀粉颗粒间的界限逐渐清晰,馒头淀粉颗粒表层出现纹状结构。

The changes during storage process of the physicochemical indexes of steamed bread were studied. The changes of microbial quantity, whiteness and hardness, water activity, gelatinization and microstructure of steamed bread during the storage process were measured. The result showed that, during the storage process, the water activity maintained a high level, and the mold counted gentle rise first, and then increased dramatically. The whiteness declined slightly, but remained unchanged. The hardness increased, but the gelatinization showed a gradual downward trend. The combination of starch and gluten protein of steamed bread was loose, and became clear gradually during the storing process, and the surface of the starch granule appeared grain structure.