Control de temperatura con PID e iluminación con voltaje continuo para la evaluación del efecto sobre el índice de estabilidad del aceite de soya (Glycine max)

Abstract

Currently, food products, such as oil, are displayed at high lighting intensities and sometimes at temperatures above 20 °C, factors that can accelerate oxidative rancidity, such as degradation of oil quality. This is the reason why a PID (Proportional-Integral-Derivative) control system was implemented that allowed quality tests to be carried out on the oil stored in different temperature conditions (13 °C to 27 °C). During these tests, the transfer function of the system and the controller, was found using the automatic tuning of the control box. This improved the precision and continuous voltage for illumination (from 155 lux to 1145 lux) by varying the intensity of the LEDs. For the experimental design, the central composite design (CCD) was used, resulting in 13 treatments. After 30 days, the quality of the oil was evaluated (acidity index and peroxide index), and the oxidative stability index was determined using the Rancimat method. It was found that temperature and lighting have a significant effect on the quality and oxidative stability of the oil (p < 0.05), achieving the storage condition with greater stability at 300 lux of lighting and 15 °C temperature.