Optimization of Liquid Soap Formulation Through Saponification: Evaluation of Emulsion Stability and Factors Affecting Product Homogeneity

Abstract

Drying is one of the most widely applied food preservation techniques for extending shelf life by reducing moisture content and water activity while maintaining product quality. This study aimed to compare the effectiveness of natural sun drying and controlled oven drying in preserving selected agricultural commodities, including banana, corn, and apple, through the evaluation of drying performance, product yield, and organoleptic characteristics. Fresh samples were pretreated with a 1% ascorbic acid solution to minimize enzymatic browning before being subjected to either sun drying for approximately 72 h or oven drying at 60°C for 6–8 h. Initial and final sample weights were recorded to determine product yield and moisture loss, while qualitative observations of color, texture, aroma, taste, and drying uniformity were conducted after dehydration. Sun drying effectively reduced sample moisture in all commodities but required substantially longer processing time and produced greater variability in drying performance due to environmental conditions. Oven drying generated more uniform dehydration, superior color retention, improved texture, and greater processing efficiency. However, quantitative measurements for oven-dried banana and apple samples contained inconsistencies, indicating experimental or recording errors that limited direct quantitative comparisons. Despite these limitations, the qualitative findings agreed with established drying principles, demonstrating that controlled thermal drying generally provides higher process efficiency and more consistent product quality than traditional sun drying. These findings reinforce the importance of appropriate drying technology in food preservation and emphasize the need for accurate experimental measurements to improve the reliability of laboratory-based drying studies.