Physicochemical, nutritional, antioxidant properties and stability monitoring of coconut (Cocos nucifera L.) water from two localities in Cameroon

The nutritional value of a food is linked to the quality and quantity of the nutrients it contains. It offers a major advantage in establishing a food table composition (FTC) which is a tool that provides information on the quantity of nutrients contained in a food. Furthermore, certain natural beverage are not taken into account in the FTC. This is the case of the water of Cocos nucifera nuts, although widely consumed around the world. The aim of this study was to valorise the water of Cocos nucifera nuts (mature and mid-mature) to contribute to the enrichment for the cameroonian FTC. Physicochemical, nutritional and antioxidant parameters were assessed by standard methods. Physicochemical analyses showed that mid-mature nuts from Edea and Bafia, have respectively an average of 0.2 ± 0.04 and 0.19 ± 0.05 mL of water/g of nut, with soluble dry extract of 4.3 ± 0.28 and 5 ± 0.0°B for a pH of 5.01 ± 0.01 and 5.11 ± 0.0. The total titratable acidity was of 0.113 ± 0.0 and 0.117 ± 0.0 mg citric acid per 100 mL water. The mean contents of total and reducing sugars, proteins, free amino acids and lipids in the same samples were 5.49 ± 0.05 and 5.56 ± 0.04; 5.09 ± 0.6 and 4.99 ± 0.7; 0.12 ± 0.0 and 0.15 ± 0.0; 0.06 ± 0.0 and 0.09 ± 0.0; 0.07 ± 0.0 and 0.10 ± 0.0g/100 mL of water, respectively. These data showed that from mid-maturity to full maturity, there was a significant increase (p < 0.05) in pH, lipid, protein, free amino acid, and phenolic contents and decrease in water volume, total titratable acidity, total and reducing sugars contents. In general, mineral contents increased significantly (p < 0.05), while total antioxidant power decreased with maturity. As for stability, degradation processes are more intense at room temperature than in the refrigerator.