Comparative Effects of Purification Methods on the Yield and Functional Qualities of Cashew Gum

Abstract

Aims: Plant hydrocolloids, such as exudates from the Anacardium occidental (cashew) tree, play an important role in food industry. However, prior to utilisation, raw exudates must undergo a purification process, to yield a purified gum with optimal technological properties. Methodology: In order to enhance the value of cashew gum exudate from Ivorian cashew plantations, the stem exudate was collected and purified. The present study therefore sought to investigate the effect of purification methods on the yield, physico-chemical constituents, and functional properties of cashew tree gum exudates. Place and Duration Study: Department of Agriculture, Fisheries Resources and Agro-Industries, University of San Pedro, Southern Côte d'Ivoire, 2025. Results: The results of the analysis of variance demonstrated that the yield, physicochemical and functional properties of the purified gums were influenced by the different purification reagents employed (ethanol, isopropanol, a combination of ethanol and isopropanol, and Fehling's solution). It was demonstrated that gums purified with isopropanol exhibited a superior purification yield (82.16%) and important mineral composition, along with optimal oil retention capacity (615.23 g/g) in refined palm oil. However, it was observed that gum obtained from Fehling's solution purification exhibited higher carbohydrate, galactose, water solubility, and water holding capacity. However, it was observed that the purifications did not result in the complete removal of the protein fraction. All purifications significantly improved the solubility and water-holding capacity of cashew gum (p ≤ 0.05), in contrast to the reduced oil-holding capacity of cashew gum. Conclusion: The precipitation method employing Fehling's solution (method D) has been demonstrated to yield a more purified cashew gum product with a reduced protein content. This method has been shown to be advantageous for cashew gum applications in emulsion stabilization.