Effects of re-frying processes on the quality and volatile flavor compounds of pre-fried coated tofu

Authors

• Nie Jingwen, College of Food Science and Chemical Engineering , Shaoyang University , Shaoyang , Hunan 422000 , China ;Hunan Provincial Key Laboratory of Soybean Products Processing and Safety Control , Shaoyang , Hunan 422000 , China ;Hunan Engineering Research Center of Green Processing and Equipment of Hunan-Style Food , Shaoyang , Hunan 422000 , China
• Chen Hao, College of Food Science and Chemical Engineering , Shaoyang University , Shaoyang , Hunan 422000 , China ;Hunan Provincial Key Laboratory of Soybean Products Processing and Safety Control , Shaoyang , Hunan 422000 , China ;Hunan Engineering Research Center of Green Processing and Equipment of Hunan-Style Food , Shaoyang , Hunan 422000 , ChinaFollow
• Zhao Dan, College of Food Science and Chemical Engineering , Shaoyang University , Shaoyang , Hunan 422000 , China ;Hunan Provincial Key Laboratory of Soybean Products Processing and Safety Control , Shaoyang , Hunan 422000 , China ;Hunan Engineering Research Center of Green Processing and Equipment of Hunan-Style Food , Shaoyang , Hunan 422000 , China
• Zhou Xiaohu, College of Food Science and Chemical Engineering , Shaoyang University , Shaoyang , Hunan 422000 , China ;Hunan Provincial Key Laboratory of Soybean Products Processing and Safety Control , Shaoyang , Hunan 422000 , China ;Hunan Engineering Research Center of Green Processing and Equipment of Hunan-Style Food , Shaoyang , Hunan 422000 , China
• Yang Dajun, Sichuan Han Bean Craftsman Food Co ., Ltd., Chengdu , Sichuan 611530 , China
• Zhao Liangzhong, College of Food Science and Chemical Engineering , Shaoyang University , Shaoyang , Hunan 422000 , China ;Hunan Provincial Key Laboratory of Soybean Products Processing and Safety Control , Shaoyang , Hunan 422000 , China ;Hunan Engineering Research Center of Green Processing and Equipment of Hunan-Style Food , Shaoyang , Hunan 422000 , China

Corresponding Author(s)

陈浩（1989—），男，邵阳学院副教授，博士。E-mail：[email protected]

Abstract

[Objective] To investigate the effects of deep frying process (DFP), microwave process (MP), and air frying process (AFP) on the quality and aroma characteristics of pre-fried coated tofu. [Methods] The optimal re-frying conditions are selected using slurry exudation rate, moisture content, color difference, and sensory evaluation as indicators. Subsequently, the re-frying method most suitable for consumers is comprehensively determined based on texture properties, oil content, malondialdehyde content, electronic nose analysis, and volatile compound composition. [Results] Under the three re-frying methods, the coated tofu exhibits an increase-then-decrease trend in slurry exudation rate and sensory evaluation, accompanied by a continuous decline in moisture content and a gradual shift to yellow color. The optimal conditions for each re-frying process are: 170 ℃ for 30 s in oil (the DFP group), 350 W for 60 s (the MP group), and 170 ℃ for 180 s (the AFP group). Under these optimal conditions, coated tofu in the AFP group exhibits a crispy and golden crust along with a tender and smooth slurry texture. It exhibits hardness and springiness values of 2.47 N and 0.96 mm, respectively, indicating superior overall texture quality compared to the other re-frying processes. Meanwhile, it shows a relatively low fat content of 31.34 g/100 g. Flavor analysis indicates that the AFP group effectively restores the flavor profile of oil re-frying. Furthermore, among the 45 identified volatile compounds, air-fried samples demonstrate high concentrations of alcohols and esters, imparting characteristic oiliness and fruity aromas. [Conclusion] Air frying offers significant advantages in reducing oil content and improving edible quality.

Publication Date

9-20-2026

First Page

175

Last Page

188

DOI

10.13652/j.spjx.1003.5788.2026.80359

Recommended Citation

Jingwen, Nie; Hao, Chen; Dan, Zhao; Xiaohu, Zhou; Dajun, Yang; and Liangzhong, Zhao (2026) "Effects of re-frying processes on the quality and volatile flavor compounds of pre-fried coated tofu," Food and Machinery: Vol. 42: Iss. 8, Article 22.
DOI: 10.13652/j.spjx.1003.5788.2026.80359
Available at: https://www.ifoodmm.cn/journal/vol42/iss8/22

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