Identification of Ingredients for Stabilizing Frying Oil Through a New Screening Method

Frying oils are prone to quality deterioration; because of the high surface area, lipid molecules can interact with air, moisture, and oxidative reagents that promote various reactions. However, the search for effective ingredients for stabilizing frying oil has been slow, given the complexity of the frying processes and lack of effective tools to accurately predict the performance of emerging ingredients. On the other hand, demand for label-friendly food ingredients has increased. This study aimed to develop a rapid method mimicking real frying conditions to allow the screening of a large number of treatments with improved throughput, while evaluating their effectiveness in stabilizing frying oils. The design utilizes multi-well heating blocks of conventional OSI. Repeated frying was conducted using miniature baskets, and validations were conducted to examine the accuracy of the relative efficacy of individual treatments. Utilizing this method as a tool, natural plant extracts, standard antioxidants, and their combinations were evaluated and compared in frying palm oil, which demonstrated that the combination of tocopherols, rosemary extract, and oil-soluble green tea extract was effective for the stabilization of frying oil.