Optimization of process variables on physical and sensory attributes of shiitake (Lentinula edodes) slices during vacuum frying

Abstract

Abstract As an important research aspect in food industry, fried products possessing both low oil content and good appearance still poses a challenge. The processing parameters of vacuum fried shiitake mushroom slices were investigated using response surface methodology. Frying temperature, vacuum pressure and frying time were studied as independent variables due to their significant effects on the quality attributes. Temperature and vacuum pressure presented the opposite effects on the four responses, for instance, the enhancement of fracturability and sensory performance and the reduction of color difference and oil absorption were observed as the temperature decreasing and vacuum pressure increasing. However, frying time generally induced all the response values increased among the testing range but only fracturability decreased after 28 min. In the optimal vacuum frying condition of frying temperature 105 °C, vacuum pressure −0.085 MPa and frying time 27.3 min, the total oil content and sensory values were observed to be 33.54% higher and 18.78% lower than those in conventional frying condition. The reason was supposed to be stronger surface-related phenomenon due to faster moisture loss and the resistant structure formation as starch gelatinization in vacuum frying environment. It provided a feasible optimized vacuum frying process for low-oil content and comprehensive acceptability fried shiitake slices.