Microwave-assisted extraction of bioactive components from peach waste: describing the bioactivity degradation by polynomial regression

Abstract

The number of studies in degradation stability modelling is relatively poor and scarce. Observing the storage stability of the natural products with bioactive properties is of great value to both producers and consumers. Microwave-assisted extraction has been used to extract high added-value substances from the peach peels. Sixteen polynomial regression models have been developed for 4 measured variables kept at 4 conditions to describe the degradation process in the extracts. In order to optimize the extraction system, response surface method was used. After the extract was obtained under the optimized conditions, the samples were exposed to several storage media such as -20 degrees C, 4 degrees C, and 25 degrees C in dark and 25 degrees C in light. Storage stability was monitored in terms of 4 bioactive properties (total phenolic material and total anthocyanin contents, p-hydroxybenzoic acid and p-coumaric acid). Degradation process was the least in the concentration of total phenolic material (38%), while total anthocyanin content, and p-hydroxybenzoic acid and p-coumaric acid concentrations decreased by similar to 61, 65, and 62% after 2 months. Deep freezer conditions gave the longest shelf life in terms of the selected responses with satisfactoy findings between the actual and estimated results (R-2 >0.94 and error rate<0.31%). The highest yields were obtained with 80% ethanol solvent system at 500 W microwave power for 90 s. The longest shelf life in terms of total phenols, anthocyanins, and major phenolic compounds (p-hydroxybenzoic acid and p-coumaric acid) was calculated as 111, 107, 88, and 83 days under the deep freezer conditions (-20 degrees C). The high R-2 values and the law error rates represent the success of the polynomial regression modelling study.