Effects of Methyl Cellulose and Soybean Protein Isolate Coating on Amount of Oil and Chemical Hazards in Chinese Fried Dough Cake

Abstract

Fat-related diseases and chemical hazards produced during the frying process pose a major threat to human health. Coatings have been used as a practical method to reduce the amount of oil and chemical hazards associated with fried foods. Methyl cellulose (MC) and soy protein isolate were used as coating materials to pretreat Chinese fried dough cake (CFDC) before frying. The 1.5% MC concentration was the best choice for coating to simultaneously lower oil and chemical hazards in CFDC. The CFDC prepared using 1.5% MC had 11.3% oil, 73.70 μg/kg acrylamide, 0.15 mg KOH/100 kg acid, 8.54 mmol/kg peroxide, p-anisidine value of 6.36, 0.36 μg/g malondialdehyde, 0.13 μg/g 4-hydroxy-2-(E)-hexenal (HHE), 0.51 μg/g 4-hydroxy-2-(E)-nonenal (HNE), and 4,272 μg/kg glycidyl ester. In contrast, the uncoated CFDC had 19.2% oil, 117.55 μg/kg acrylamide, 0.25 mg KOH/100 kg acid, 14.40 mmol/kg peroxide, p-anisidine value of 9.76, 0.63 μg/g malondialdehyde, 0.23 μg/g HHE, 0.86 μg/g HNE, and 5,758 μg/kg glycidyl ester. MC and soy protein isolate enhanced the oil barrier of the coating film, which effectively reduced the heat transfer coefficients, oil transfer, oil oxidation, and chemical hazards in the CFDC. Our work on this edible coating contributes to methods for control of oil and chemical hazards in fried foods.