Dynamics of Nutritional Compounds and Antioxidant Activity during Date Palm Fruit Development and Maturity Stages

Date palm fruit development involves several stages, including Habauk, Kimri, Khalal, Rutab, and Tamer stages, characterized by intricate biochemical alterations that lead to the accumulation of various metabolites. The objective of this study was to quantify and statistically evaluate the linearity of nutritional compounds, acidity levels, water content, dry matter, secondary metabolites, and antioxidant activity capacity across the fruit development and maturation stages of two date palm cultivars, Deglet Nour and Degla Beida. Fruits were collected from ten palm trees per cultivar at each growth stage, cleaned, sliced, dried, and powdered. The acidity level was assessed using the Marx method, while water content and dry matter were determined through a drying method. The carbohydrates, proteins, and fats that constitute the nutritional components were quantified using established techniques. The extraction yield of secondary metabolites was calculated using date powder. The water content, PH, carbohydrate, protein, fat content, extraction yield, total Phenol, and total flavonoid content displayed dynamic patterns described by second-order polynomials. The maximum local values for water content, PH, and carbohydrate were observed in both varieties, while the maximum local value for total Phenol was found exclusively in Deglet Nour. Conversely, the minimum local values for protein content, fat content, total flavonoid content, and extraction yield were observed in both varieties. Notably, the minimum local value for total Phenol content was observed only in Degla Beida. For both varieties, the dry matter and antioxidant activity exhibited quadratic dynamics. However, the dry matter showed a positive increasing trend, while the antioxidant activity exhibited a change in the opposite direction.