Effect of γ-tocopherol on formation of nonvolatile lipid degradation products during frying of potato chips in triolein

Formation of undesirable odors and flavors during food processing operations is an important problem for the food industry. To determine the effect of gamma-tocopherol on these negative attributes of fried food, we fried potato chips in triolein with 0, 100, or 400 ppm gamma-tocopherol. Triolein extracted from potato chips was sampled for residual gamma-tocopherol and nonvolatile degradation products after the chips were aged. RP-HPLC coupled to atmospheric pressure chemical ionization MS and size-exclusion chromatography was used to analyze samples for degradation products in the triolein absorbed in potato chips as well as the fryer triolein. MS results showed that gamma-tocopherol reduced the production of nonvolatile degradation products in the triolein absorbed by the potato chips and in the triolein in the fryer. Fryer oil samples and extracted potato chip oils with 400 ppm gamma-tocopherol had a significantly lower production of degradation compounds than did samples with 100 ppm gamma-tocopherol. Both fryer oils and potato chips containing 100 ppm gamma-tocopherol had significantly fewer nonvolatile degradation products than did the samples without gamma-tocopherol. These nonvolatile compounds are known precursors of negative odors and flavor compounds produced during the frying and aging of foods.