Title : Electrochemical stabilization of Hibiscus sabdariffa L. extracts
Abstract:
The vital role of anthocyanins in Hibiscus sabdariffa L. is now known to most consumers. consumers. The richness of anthocyanins in antioxidants, vitamin C and minerals, among others. Hibiscus juice has proven nutritional qualities. The health requirements of recent years have made food products with added preservatives or processed at high temperatures less popular, explaining new orientations towards innovative, interdisciplinary technologies. However, anthocyanins from Hibiscus sabdariffa L. are sensitive to degradation factors such as temperature, light, enzymes and oxygen. The instability of anthocyanins has long been a subject of research. The instability of anthocyanins has long been a subject of research using classic techniques such as heat treatment, the results of which are often limited by the rapid degradation and, above all, destruction of the product's nutritional and organoleptic qualities. Oxygen dissolved in juices has hitherto been treated by bubbling with an inert gas or by adding other molecules such as preservatives, which can cause a great deal of damage to health. The electrochemical approach is a new stabilization technique involving the reduction of oxygen dissolved in juices, cold and without the addition of other molecules. Hibiscus juice electrolysis was carried out using noble electrodes (Platinum and Stainless Steel) with a well-characterized Time/Potential or Time/Intensity couple. The electroreduced samples and the control samples are then stored at 4°C, 25°C and 37°C for over 6 months.
Monitoring of anthocyanins in the first month, for both samples and control, revealed a significant 10% difference between the electroreduced extract and the untreated control at 37°C, which had previously been problematic for the heat treatment and even for the other treatments. heat treatment and even for other membrane techniques. Oxygen reduction on the platinum electrode / ECS retained more than 10% of anthocyanins after 4 weeks' storage at 25°C and 37°C. At 4°C, a significant 5% difference between electro-reduced electro-reduced Hibiscus juice and the control was maintained until the fifth month of storage with a 1/5 heat/water ratio. The electrochemical technique represents a real improvement in the juice juice stabilization process, both economically and in terms of quality.
