Evaluating the Efficiency of Heat-Assisted Extraction for Fermentable Sugar Recovery from a Mixture of Carrot and Beetroot Pulp

Abstract

The aim of the study was to investigate the effects of chemical-free and low-cost heat-assisted extraction (HAE) technique on fermentable sugar and supernatant recovery from a mixture of carrot- beetroot residues. The heat treatment was carried out by analyzing the effect of pH, carrot-beetroot pulp particle size (Dp), and temperature (T). The experiments were designed using the Box-Behnken experimental model, which systematically examines the effects of multiple variables and their interactions on hydrolysis. The independent variables and their ranges were as follows: X1 (pH) = 3–6, X2 (Dp) = 90–181 μm, and X3 (T) = 50–100 °C. The dependent variables were sugar concentration and supernatant recovery percentage. Experimental results were statistically analyzed using ANOVA to identify significant variables. A quadratic response equation was developed to model the responses, and model coefficients were determined. The agreement between observed experimental results and model- predicted values was assessed using regression analysis tools, demonstrating high compatibility. The model identified the optimal conditions for maximizing sugar concentration as pH = 4.45, Dp = 135.5 μm, and T = 81 °C. Validation at two predicted points confirmed the consistency of experimental and model-predicted results, enhancing model reproducibility. In conclusion, the study demonstrates that HAE is an efficient and eco-friendly method for fermentable sugar recovery from a mixture of carrot- beetroot pulp.