Frying edible vegetable oil quality from street-food vendors in a Metropolitan area in the Central Highlands of Mexico

Abstract

Vegetable oil deterioration during frying is a health problem because of oil degradation compounds and recycled oil practices are related to disturb oil quality. Frying food street-vendors are an important part of endemic market type Tianguis at the Metropolitan areas in the Central Highlands of Mexico. The main objective of this research was to evaluate frying edible vegetable oil quality from frying by street-food vendors in a Metropolitan area in the Central Highlands of Mexico. A behaviour questionary registered fresh and recycling oil addition, frying temperature and method in real operation conditions for three working days. Free fatty acid, colour, p-Anisidine, peroxide, and TOTOX indexes were observed in the vendors by triplicate. Free fatty acids and peroxide values in two vendors exceeded the NMX-F-223-SCFI-2011 values. Physicochemical variables revealed oil oxidation deterioration. Not so high temperatures were registered, and continually fresh oil addition was suggested as mitigating or masking edible oil of thermal oxidation and its degradation agents during the observed time. Thermal oxidation could be lower than in controlled conditions as in many reports due to vendor operations studied as a real approximation that suggested less oil degradation. Present results could be evidence for government intervention in the regulation needs