Determining key factors affecting coconut sap quality after harvesting

Abstract

The production of coconut sap beverages faces a challenge with the quality of the incoming coconut sap sourced from farmers. The clarification of pivotal factors influencing the quality of coconut sap after harvesting is of paramount importance for fostering mutual benefit between the involved parties. This research focuses on assessing the quality and degradation of coconut sap during the post-harvest stage. It addresses the shortcomings in evaluating coconut sap quality and improper pick-up conditions. To improve these processes, various experiments were designed, including 1) preliminary experiments that explored microbial count, pH, and soluble solids in harvested coconut sap at varying intervals, and 2) the L9 Taguchi Orthogonal Array method. These approaches identify the optimal levels of factors such as cleaning method, storage temperature, and preservative type. By reducing the number of experiments, costs and time were minimized, 3) the 23 factorial design was implemented, reducing the levels of each factor while measuring coconut sap quality based on pH and total soluble solids (representing sweetness) at different post-harvest intervals. The results from the Taguchi method were then used to design the factorial method experiment. The analysis revealed crucial factors influencing coconut sap quality at the 10-h mark. Storage and transportation temperatures, along with the type of preservative, significantly impacted the pH value. However, the washing method and preservative type showed no statistically significant effect on Total Soluble Solids (TSS) value (p > 0.05). Recommendations include using tap water for container cleaning, opting for Payom wood as a preservative, and adhering to cold chain practices for transportation exceeding 4 h, with temperatures maintained below or equal to 10 °C. Swift sap collection within 4 h post-harvest, coupled with stringent temperature control during transportation (not exceeding 10 °C), is advised to ensure optimal quality. Integrating pH with TSS values enhances comprehensive quality assessment, aligning with established best practices in coconut sap handling.

Keywords

• Coconut sap
• Factorial design
• Preservative type
• Taguchi
• Temperature
• Washing method