Avaliação de alterações físico-químicas em óleo vegetal submetido ao processo de fritura em uma unidade de alimentação hospitalar.

Abstract

Frying is a fast, practical and economical method of cooking that gives at foods pleasant sensory characteristics and is commonly used in food and nutrition units. Vegetable oils, when submitted to frying process at high temperatures and long periods of exposure, can suffer physic-chemical alterations causing degradation compounds potentially toxic and harmful to health. In this study the purpose was to evaluate the physic-chemical changes of vegetable oils used in frying process in a hospital food unit located in the city of Campina Grande/PB. Samples of vegetable oil (soybean) were collected at three different times: T0, virgin oil without heating; T1, oil on medium usage time under frying; and T2, discard point. To measure the temperatures, it was used digital infrared thermometer. Measurements of acidity and peroxide index were performed in duplicate and based on the methodology recommended by the Instituto Adolfo Lutz. Data were analyzed by analysis of variance (ANOVA) and Tukey's test (p≤0.05), to means comparison. To evaluate good practices of frying was applied a check-list elaborated based on the Technical Report nº 11 of the Anvisa. The results obtained showed that one of the preparations (meatballs) exceeded the maximum limit of 180°C recommended frying temperature. About acidity, all samples had values within the recommended by legislation. Peroxide index presented unstable and above the required limits, exception of oils at room temperature (T0). The check-list showed the occurrence of nonconformities about use of frying oil. We conclude that other tests are needed to confirm degradation’s level of frying oil, once only peroxide index exceeded required limits, and this method isn’t considered an accurate indicator of oil degradation level. Based on results obtained, it is inferred that the oil, possibly, would be able to reuse, resulting in costs reduction for the Service. Highlights the importance of correcting non-compliances observed through educational activities with handlers responsible for food preparation, addressing methods and techniques of frying recommended by legislation to improve the quality of Service.