包子熟制之后需要冷却然后才能进行包装贮藏,为找到最适合熟制包子的冷却方式,文中通过对产品进行自然冷却、鼓风冷却、真空冷却和混合冷却4种不同的处理,比较其在同一温度下贮藏不同时间的品质变化。结果表明:不同冷却方式对产品保质期有不同影响(P<0.05),混合冷却方式具有取代常规冷却和真空冷却方式的可行性。混合冷却的质量损失明显低于真空冷却而冷却速率显著快于常规冷却方式;在色泽方面混合冷却可以改善真空冷却的颜色较暗这一缺点;在硬度与电子鼻分析方面混合冷却与常规冷却相比有较明显差异(P<0.05),但相对于真空冷却已有提高,在黏聚性、黏性、咀嚼性等方面混合冷却与常规冷却没有显著差异(P>0.05);感官评分的可接受性明显优于真空冷却。在化学指标测定方面:混合冷却与真空冷却对pH值变化的影响较小(P>0.05)并且可以降低包子皮的老化程度;混合冷却与真空冷却均可以显著延缓微生物污染和脂肪氧化程度,从而达到延长食品货架期的目的。

Buns needed to cool after cooking before packaged and stored. The purpose of the study was to find the most suitable cooling method. The products used four different ways for cooling including natural cooling、blast cooling、vacuum cooling and hybrid cooling. These methods were compared for qualitative changes of the buns during storage time in the same temperature. The results showed that: different cooling methods had different effects on the shelf life( P < 0. 05). It was feasible to use hybrid cooling to replace the conventional cooling and vacuum cooling.The qualitative loss of hybrid cooling was significantly lower than vacuum cooling and cooling rate was significantly faster than conventional cooling; Hybrid cooling could improve color to become more brighter than vacuum cooling; Hybrid cooling and conventional cooling methods had significant differences in hardness and electronic nose analysis results( P < 0. 05). Hybrid cooling had no significant differences with conventional cooling in cohesiveness、viscosity and chewing aspects( P > 0. 05),its acceptability of sensorial score was significantly better than vacuum cooling. In terms of chemical indexes : hybrid cooling and vacuum cooling had no obvious influence on pH( P > 0. 05) and could reduce the aging of bun's skin; Hybrid cooling and vacuum cooling could significantly retard microbial contamination and fatty oxidation and extend the shelf life of the buns.