Improving of texture and rehydration properties by ultrasound pretreatment for infrared-dried shiitake mushroom slices

ABSTRACT

Shiitake mushrooms are mostly used in the forms of dried products, and the pretreatments could help to improve the product quality. The effects of ultrasound pretreatment on water diffusion during short- and medium-wave infrared drying and overall product quality of shiitake mushroom were investigated. Shiitake mushroom slices were pretreated with ultrasonic wave at 28 kHz and 600 W for 15 min and then conducted infrared dried at 1350 W and 60°C. The results demonstrated that the drying time of the samples previously subjected to ultrasound pretreatment was remarkably reduced by 21.43%, as compared to the samples without pretreatment. Moreover, homogenous porous microstructure was obtained by dried mushrooms pretreated by ultrasound. In addition, the honeycomb-like microstructure pointed to superior texture, which also lead to reduce hardness and increase crispness of dried products. Furthermore, the dried products exhibited higher lightness (78.46) and better shape than those of the other pretreatment samples. In conclusion, ultrasound pretreatment coupled with infrared drying might be a potential method to produce high-quality dried shiitake mushrooms slices.

KEYWORDS:

• Rehydration ratio
• scanning electron microscopy
• short- and medium-wave infrared drying
• texture
• ultrasound pretreatment

Additional information

Funding

This work was supported by the National Key R&D Program of China (2016YFD0400700, 2016YFD0400704), and collaborative innovation task of CAAS (CAAS-XTCX2016005-3-5).