Abstract:
Response surface methodology was applied to analyze the effects of processing conditions including drying temperature and time and pre-frying time on color difference value
(ΔE), moisture and oil uptakeing of the product in the preparation of frozen French-fried potatoes. The conditions of preparation were established by means of a central rotatable composite design for drying temperature, drying time and pre-frying time in the range of 74.8~125.2℃, 10~20 min and 35~85 s at 180℃, respectively. The response variables were fitted to predictive models using multiple regression analysis. Results show that drying temperature, drying time and pre-frying time have significant effects
(p<0.05) on
ΔE, moisture and oil uptakeing of French-frieds potatoes. Applying the approach of desirability function, the parameters of processing were optimized in 108~110℃, 11~12 min for drying, and 38s at 180℃ for pre-frying. After frozen storage at -20℃ and finish frying, the product has less
ΔE of 3.99~4.45, moisture of 37.50%~38.50% and oil uptakeing of 14.34%~14.85%, which can meet the requirement of commercial products.