Studies On The Control Technology Of Oil Oxidation In Fried Potato Chips

In order to obtain the best parameters of restraining oil oxidation in the process of frying potato chips, this project began with a simulation test of quality changes of palm oil under the conditions of high temperature treatment, identified the optimal combination of relatively low content of trans fatty acid and relatively high content of cis-fatty acids in the palm oil after the treatment of normal pressure and high temperature. Then two antioxidants TBHQ and BHT were added in the process of frying potato chips under normal pressure, designed single-factor experiments of frying temperature, addition amount of TBHQ and BHT and L9 (34) orthogonal experiment, used peroxide value and carbonyl value as evaluation index, researched the oil of fried potato chips under normal pressure, then obtained optimal antioxidation parameters of frying oil through a comprehensive analysis of verification tests. Finally, utilized the optimal process parameters to produce potato chips which were also packaged and stored, potato chips for storage 0,30,60,90,120,150,180 days were extracted lipid and determined the oil index. studied the oil oxidative deterioration during the process of packaging and storing fried potato chips under normal pressure, obtained the best parameters of oil antioxidation in the potato chips during packaging and storage and mastered the situation of oil oxidation deterioration during potato chips packaging and storage, provided a reference for the practical production. The main results are as follows:(1) Within a range of 160℃-190℃of oil temperature, and processing time was 15min-60min,the addition amount of TBHQ and BHT between 0-0.005%, the best combination of using the content of cis-fatty acid and trans fatty acid to evaluate the quality of heating oil was A3B1C3D4, namely 45min of the heating time,160℃of the heating temperature, TBHQ dosage was 0.003% and BHT dosage was 0.005%.(2) Two antioxidants TBHQ and BHT were added in the process of frying potato chips under normal pressure, and used peroxide value and carbonyl value as evaluation index, researched the oil of potato chips after frying under normal pressure. Through single factor analysis, the reasonable range of frying temperature should be set to 160-180℃; TBHQ addition amount should be set to a reasonable range of 0.003-0.007%, or 30-70mg/kg; BHT addition amount should be set to a reasonable range of 0.001～0.007%, or 10～70mg/kg. Through orthogonal experiment and comprehensive verification tests analysis obtained optimal antioxidation parameters of frying oil, namely 180℃of frying temperature, TBHQ dosage was 0.003%, BHT dosage was 0.005%.(3) Used packaging materials of Aluminum foil paper bags and polyethylene bags, under the temperature of 5℃and 20℃, the modified atmosphere packing was inflated with nitrogen and air, the optimal combination of the inhibition of oil oxidation deterioration in potato chip was A1B1C2, which used peroxide value as evaluation index. Used acid value as evaluation index, the optimal combination of the inhibition of oil oxidation in potato chip was A1B2C1. The optimal combination of the inhibition of oil oxidation in potato chip was A1B1C2, used carbonyl value as evaluation index. Through the range analysis of the orthogonal results and according to the principle of not considering the combination of secondary factors, according to the orthogonal experiment result of each index changes through different storage time of chips can come to a conclusion that the best combination of restraining oil oxidation and deterioration during the process of packaging and storage was A1B1C1, namely 5℃of storage temperature, Nitrogen filling and Aluminum foil bags of packaging.