English abstract
The study evaluated the nutritional quality and glycemic index of three sun-dried date varieties (Khalas, Khsab and Fardh) grown in three different regions (A'Dakhlia, A'Dhahira and Al-Batinah) of Oman. Dates were analyzed for proximate chemical composition, dietary fiber contents and various sugar fractions. The glycemic index of dates was determined in 10 healthy human volunteers using pure glucose as a standard food. Significant (P < 0.05) differences were observed in the proximate chemical composition, dietary fiber contents, various sugar fractions and energy value of these dates. The percentages (g per 100g on as such basis) of moisture, ash, crude protein, total fat, and nitrogen free extract (NFE) ranged between 18.77-23.71, 1.12-1.55, 1.28-1.89, 1.14-2.37, 68.53-75.37 respectively. The energy values ranged between 301 to 319 kcal/100g. The dietary fiber content of the date samples ranged between 8.83 to 13.11 g/100g whereas the total sugar content ranged between 52.17– 59.96 g/100g. The glycemic index of different varieties of dates from various regions (Khasab Dakhlia, Khsab Dhahira, Khsab Batinah, Khalas Dakhlia, Khalas Dhahira, Khalas Batinah, Fardh Dakhlia, Fardh Dhahira and Fardh Batinah) were 61.9, 54.1, 54.6, 51.9, 50.3, 59.3, 53.5, 46.2 and 52.6 respectively. Overall on the average the variety Fardh showed significantly (P < 0.05) lower GI value (50.8) as compared to other two varieties Khsab (56.9) and Khalas (53:9). The regional effects on glycemic index of dates were however non-significant (P >0.05). No significant differences were observed between the glycemic index of dates served either with water or with Arabian coffee.
