The impact of ultrasound and blanching technology on effective diffusivity and uptake of oil in zucchini during deep fat frying

Frying is considered as one of the most popular methods of fast food cooking with desirable sensory characteristics as well as an important inclusive and diverse process. Since the tendency to consume fried foods with lower oil content has increased today, pretreatments such as enzymatic and ultrasonic treatment can reduce the absorption of fried oil and improve the sensory properties of food. In this study, pretreatment with hot water enzyme at 85 ° C for 2 and 4 minutes and ultrasound pretreatment at 37 kHz at 20 and 40 minutes. The effect of the above treatments on oil uptake and sensory properties was investigated. The results show that moisture diffusion coefficient increases with increasing temperature in all pretreatments due to faster exit of moisture from nutrients. The highest moisture diffusion coefficient was observed at 190 ° C. As the frying temperature increased, the oil content in the food decreased. Regarding the moisture content, there was a significant difference between control and ultrasound-treated and control enzyme samples (P<0.05). There was no significant difference between the treated enzyme samples in 2 minutes and the enzyme samples in 4 minutes (P>0.05). The shrinkage was reduced in all of the above treatments so that in the pre-treated ultrasound samples for 20 and 40 minutes were less wrinkled than the control and enzymatically treated samples. However, the difference between the ultrasound pre-treated samples for 20 minutes with the enzymatically treated samples was not significant (P>0.05).