Determination of Deep Frying Soybean Oil Disposal Point by a Sensory Method

• Published in: Journal of the American Oil Chemists' Society 2010-05, Vol.87 (5), p.515-520
• Main Authors: Ravelli, Débora, Matsuoka, Carla Romero, Della Modesta, Regina Célia, Vieira, Thais Maria Ferreira de Souza, Regitano-d'Arce, Marisa Aparecida Bismara
• Format: Article
• Language: English
• Subjects: Acids; Agriculture; Biological and medical sciences; Biomaterials; Biotechnology; Chemical properties; Chemistry; Chemistry and Materials Science; Cooking; Deep fat frying; Fat industries; Fatty acids; Food industries; Food Science; Fundamental and applied biological sciences. Psychology; Industrial Chemistry/Chemical Engineering; Original Paper; Oxidation; Polar compounds; Sensory analysis; Sensory perception; Soybean oil; Soybeans; Trans fats; Vegetable oils
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/s11746-009-1524-y

Measurements of degradation in frying oils are mainly based on physico-chemical properties. Total polar compounds (TPC) and free fatty acids (FFA) content in frying oils are used as a guide for discarding used oils. The purpose of this study was to evaluate the efficacy of a sensory method in detecting degradation in soybean oils used in potato chips deep frying. The sensory evaluation of oil samples was determined by a trained panel; after rigorous selection and training steps. Free fatty acid, TPC and Rancimat induction period (IP) were quantified in the same samples. The proposed sensory method was sensitive to small differences in rancidity. The selected and trained sensory panel discarded oil samples with 0.175% FFA as oleic acid, 18.92% TPC, and 0.20 h IP. According to the results achieved in this research sensorial trained panel response is sensitive and accurate in refusing deteriorated frying oils. Besides this, soybean oil can be used for deep frying procedures and safely discarded according to the panel response, although presenting up to 7% linolenic acid.