Physico-chemical characteristics and stability aspects of coconut water and kernel at different stages of maturity

Abstract

Coconut water and kernel are the edible portions of the coconut. A study was carried out to evaluate the physico-chemical characteristics, phytonutrients and stability of coconut water (CW), kernel (CK) at different stages of maturity and commercial coconut products (CCP). The moisture content of CW, CK and CCP were in the range of 95–97 g 100 g⁻¹, 50–85 g 100 g⁻¹ and 0.4–3 g 100 g⁻¹ respectively. Fat content in CW was low (4–115 mg 100 g⁻¹) whereas in kernel it was high (37–56 g 100 g⁻¹). The CW was acidic in nature (pH 4.5–5.2). Ash content of CK decreased with maturity (1.0–1.5 %) whereas that of CW remained steady (0.3–0.4 g 100 g⁻¹) with maturity. The total sugar content (3.9–4.6 g 100 g⁻¹) and acidity (0.3–0.4 g 100 g⁻¹) of CW did not change with maturity. The phenolics content increased in water (1.4–4.3 mg 100 g⁻¹) and kernel with maturity (18.5–24.8 mg 100 g⁻¹). The fatty acid composition of the oil extracted from the CK had increased saturated fatty acids (C_12:0) (38–48 g 100 g⁻¹) and decreased monounsaturated fatty acid (C_18:1) (13–5 g 100 g⁻¹) with maturity. The percentage of medium chain fatty acids increased with different stages of maturity (47–78 g 100 g⁻¹). The CW and CK contained higher amount of phenolics (1.4–4.3 mg 100 g⁻¹ and 18.5–24.8 mg 100 g⁻¹ respectively) and total tocopherols of CK (0.14–0.59 mg 100 g⁻¹) when compared to CCP. This study indicated that CW and CK could serve as valuable raw materials for the preparation of functional food supplement.