Impact of freeze drying on the properties of palmitic acid extracted from Plantain stalk waste

Abstract

The challenge of effectively preserving and concentrating palmitic acid from plantain stalk waste is compounded by the loss and degradation of the compound during traditional drying and extraction methods, which may lead to reduced yield and altered properties of the extracted palmitic acid. This study was aimed at evaluating the impact of the freeze-drying process on the properties of palmitic acid extracted from plantain stalk waste. The study involved preparing plantain stalks, applying freeze-drying or non-freeze-drying methods, extracting palmitic acid, and characterizing the samples using GC-MS, FTIR, XRD, EDX, and SEM. The GC-MS analysis revealed that freeze-drying significantly increased the concentration of palmitic acid compared to non-freeze-drying, as indicated by the higher peak area and height. FTIR spectra demonstrated that freeze-drying better preserved the structural integrity of palmitic acid, while XRD analysis showed enhanced crystalline structure and increased crystallite size in the freeze-dried sample. Additionally, EDX showed that freeze-drying increased the carbon content and decreased the oxygen content of the material, while SEM analyses indicated that freeze-drying resulted in a more porous and irregular surface compared to the denser, smoother structure of the non-freeze-dried sample. The mass, energy, and cost analysis revealed that freeze-drying resulted in a higher yield of palmitic acid compared to non-freeze-drying methods, which, despite being more cost-effective and requiring less energy, demonstrated a notable trade-off in extraction efficiency. The study showed that freeze-drying significantly improved the preservation, concentration, and structural integrity of palmitic acid extracted from plantain stalk waste compared to the non-freeze-drying method.