Physicochemical, microbiological, and nutritional characterization of Tahlaout, a traditional Moroccan date-based product

Abstract

Aim: This study aimed to evaluate the physicochemical, functional, and microbiological quality ofTahlaout, a traditional date-based product from the Draa-Tafilalet region of Morocco. The main objective is to compare these characteristics with international standards, including Gulf date syrup (dibs) and Egyptian date honey, to assess their potential for market valorization and formal recognition. Methods: A cross-sectional analytical and comparative study was conducted on thirteenTahlaout samples collected from different women-led cooperatives. Physicochemical parameters, including pH, degree Brix (°Bx), water activity, dry matter (DM), ash content, reducing sugars, viscosity, and color, were determined using standardized methods. Functional and nutritional properties were assessed by quantifying total polyphenols, flavonoids, antioxidant activity, and mineral composition. Microbiological quality was evaluated by enumerating aerobic mesophilic flora, yeasts, molds, and total coliforms. Results: The majority ofTahlaout samples complied with international quality standards and exhibited high levels of bioactive and nutritional compounds: mean total polyphenol content (TPC) of 26.68 mg GAE/gS (range: 14.16–33.88), mean total flavonoid content (TFC) of 14.46 mg RE/gS (range: 5.93–23.19),mean ferric reducing antioxidant power (FRAP) of 7.80 mmol Fe²⁺/gS (range: 3.52–11.50), and mean DPPH inhibition of 56.93% (range: 50.81–79.32). Mineral analysis yielded a mean iron content of 5.20 mg/100 g DM (4.27–6.58), zinc of 0.43 mg/100 g DM (range: 0.25–1.45), copper of 0.96 mg/100 g DM (range: 0.77–1.35), and manganese of 1.9 mg/100 g DM (range: 1.34–2.49). Microbiological analyses indicated generally satisfactory quality. However, elevated coliform and yeast counts were detected in certain samples, suggesting possible contamination during or after processing. Conclusions: Tahlaout demonstrates strong potential as a high-quality traditional date-based product. Nevertheless, improvements in hygiene practices and the implementation of standardized certification protocols are necessary to ensure product safety and consistency. These findings support the formalization and sustainable development of the Tahlaout sector and contribute to the valorization of the date industry in Moroccan oasis regions.

Keywords

Tahlaout / date-based product / nutritional quality / microbiological quality / Moroccan oasis regions / valorization

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