Physicochemical composition of different varieties of raisins (Vitis vinifera L.) from Tunisia

Raisins should be of particular interest in the investigation due to their unique phytochemical composition, and their natural qualities make them an appealing source of nutrients. In this study, physicochemical composition including weight, length, diameter, moisture, ash, protein, fat, carbohydrate, total sugar, fructose, glucose and some minerals (Na, Mg, K, Fe, Ca and P) of five Tunisian varieties of raisins were studied. Based upon statistical analysis, all varieties of raisins were a rich source of carbohydrate ranging from 65.86 ± 0.81% (in Meski) to 76.62 ± 0.86% (in Raseki), and glucose was the main sugar ranging from 32.37 ± 0.70% (in Meski) to 37.33 ± 0.28% (in Chriha) followed by fructose from 26.13 ± 1.14% (in Karkni) to 31.21 ± 0.29% (in Chriha). Important minerals were found in raisins include 628–854 mg/100 g DW potassium; 49.6–95.2 mg/100 g DW calcium and 28.67–41.79 mg/100 g DW magnesium. Considering the composition of raisins and the fact that they have no fat, it is no wonder that this fruit was considered a healthy snack.

► Raisins are a rich source of carbohydrate.
► Glucose and fructose are two principal sugar detected in all the varieties of raisins.
► Important minerals are detected in raisins such as potassium, calcium and magnesium.