2.5. Chemical analysis
The proximate analysis and determination of titratable acidity followed the official methods of analysis described by the Association of Official Analytical Chemists (Association of Official Analytical Chemists, 2005). Carbohydrate was determined by difference. The pH of the samples was determined using the Jenway 3505 pH meter, following standard procedures given in AOAC (2005). All analyses were carried out in triplicates.