Influence Of Lipid Degradation Product-acrolein On The Formation Of Acrylamide During Potato Chips Frying Process

Acrylamide is a kind of effective accumulation of toxic which would harm human beings’ many systems like nervous system, respiratory system, et al. So far, a number of proposed mechanisms of acrylamide formation were published. However, most of these previous works focused on the effect of Millard reaction on the formation of acrylamide in foods, ignoring the oil and leaving a blank in the investigation of the mechanisms of acrylamide formation. So it is important for food safety to do research on the formation of acrylamide and influential factors in foods during heat processes. Hence, This subject did research about the acrolein generated from lipids and its relationship with formation of acrylamide in fried potato chips.Meanwhile, changing laws of acrylamide with material characters and frying parameters were investigated to help control the acrylamide contents in the foods. The main results were as followers:Firstly, research of the resource of acrolein and ammonia in fried potato chips system and the confirmation of acrolein method were did. Heating results of degradation product of lipid-glycerin and fatty acid indicated the presence of acrolein. The average value of acrolein formed from glycerin under 175℃ was 106.9 μg/kg per hour, palmitic acid 551.3 μg/kg,stearic acid 263.2 μg/kg, oleic acid 34796.0 μg/kg and linoleic acid 24395.2 μg/kg under the same condition. The amount of acrolein formed from fatty acid was more than glycerin and unsaturated fatty acid much more than saturated fatty acid. Asparagine was chose as substrate to be heated, and the results showed that the concentration of ammonia formed in the heating system with asparagine was 45.5% higher than that with asparagine and palm oil together.The HPLC-MS/MS analysis of asparagine and palm oil’s resultant assured the presence of acrylamide in it.Secondly, results of detection of some basic indexes, acrylamide content and research of the relationship of acrolein and acrylamide showed that the concentrations of acrylamide in potato chips fried with different oils were different from each other: palm oil 949.2 μg/kg>sunflower oil 878.7 μg/kg>rapeseed oil 484.3 μg/kg>soybean oil 187.3 μg/kg, from which we can find that soybean oil decreased the acylamide content in frying potato chips.Correlation analysis results of acrolein and acrylamide showed the conclusion: high concentration of acrolein led to low concentration of acrylamide no matter between different batches of potato chips in the same frying oil or between different frying oils.Thirdly, other factors that have impact on acrylamide were analysed. Under different frying temperatures, from 160 ℃ to 200 ℃, acrylamide formed more and more as the temperature increased; using water-oil separation pot could decrease the acrylamide leveleffectively than ordinary frying method; acrylamide concentration would decrease as the water content in potato chips increased, but no influence was made by the change of acid value of oil.