复水温度对香菇复水特性及品质的影响

香菇是中国产量最高和市场消费量最大的食用菌。干制是香菇的主要加工方式,而干香菇需复水后才能作为原料被烹调或进一步加工。本研究将热风干燥的香菇分别在25,45,65℃和85℃下复水,研究香菇复水过程中复水比、外观、质构和风味品质的变化。结果表明,在45℃复水270 min,干香菇吸水后表面的褶皱较为舒展,微观结构显示其菌丝恢复膨胀且伸展。同时,其复水比稳定保持在3.88,剪切力(1 290.28 g)、弹力(0.66 g)和复原力(0.34 g)适中,咀嚼性(656.02 g)最大,说明香菇复水完全且质地柔软适中,易被切开。此外,45℃复水香菇所含特征含硫化合物的含量较高,以1,2,3,5,6-五硫杂环庚烷(67.02%)和1,2,4-三硫环戊烷(39.06%)为主,风味较浓郁。综上,复水温度显著影响香菇复水后的食用品质,将干香菇在45℃复水270 min可获得品质较好的复水香菇。

Effect of Rehydration Temperature on Rehydration Properties and Quality of Shiitake Mushrooms(Lentinus edodes)

Shiitake mushrooms(Lentinus edodes), the largest production and consumption of edible fungus in China.Drying is the most common processing approach for shiitake mushrooms, and the dried products should be rehydrated before consumption. In order to obtain the optimum condition for rehydration of dried shiitake mushrooms, hot-air dried samples were immersed in distilled water at 25, 45, 65 ℃ and 85 ℃ respectively, and the rehydration ratio, appearance, texture and flavor were investigated. The results showed that when sample was rehydrated at 45 ℃ for 270 min, the equilibrium rehydration ratio was 3.88, and the mushroom hyphae were fully rehydrated and swollen. Moreover, the shear force, elastic, resilience and chewiness of the rehydrated mushrooms were 1 290.28 g, 0.66 g, 0.34 g and 656.02 g, respectively, which were moderately soft and easy to cut. Furthermore, the content of sulfur compounds of the mushrooms rehydrated at 45 ℃ was relatively high as compared with other samples. Sulfur compounds such as 1,2,3,5,6-pentathiheptane(67.02%) and 1,2,4-trisulfide cyclopentane(29.06%) were rich in the flavor compounds. In conclusion, the rehydration characteristics, appearance, texture and flavor were significantly affected by water temperature, and the rehydrated mushrooms with higher quality were obtained at 45 ℃ for 270 min. The optimized condition can be used to guide the rehydration operation of shiitake mushrooms for cooking and food industry.