Propriétés physicochimiques et microbiologiques et anti-oxydante de sirop de datte de la région du sud-ouest d’Algérie

Abstract

Introduction. The palm-date syrup “Robb” is a product that belongs to Algerian culinary traditions, it has nutritional and economic value. Objective. The aim of this study was to evaluate and compare the physicochemical and microbiological parameters, and antioxidant activity of Hmira and Tagazza dates syrups, and also a sensory analysis of final product. Material and methods. Physicochemical analyses were based on the measurement of pH, free acidity, electrical conductivity, water content and total sugars, lipids, and ash rate. Microbiological tests of total germs, sulfo-reducing clostridium, streptococci, staphylococcus were realized. The method of 2,2-diphényl-1-picrylhydrazyl (DPPH) free radical scavenging was used to evaluate antioxidant activity of the syrups produced. Then, a survey was carried out on 100 students focused on the ‎product knowledge, and organoleptic characterization‎. Results. Physicochemical results of syrups showed that pH was acid (=4), and free acidity was 13. Electrical conductivity was low than 3 ms/cm. However, Brix degree of syrups was of 80%, approximately. Microbiological tests showed a low presence of recorded bacteria, and the absence of yeast and mold. Antioxidant activity with IC50 of 0.32 and 0.6 mg/mL was noted for Hmira and Tagazza syrup, respectively. Sensory analyze of tasters was dissimilar in terms of preference. Conclusion. The results of the different syrup analyses based on Hmira and Tagazza ‎‎(Robb) can be used for standardization of physicochemical and ‎microbio-logical parameters, and antioxidant activity at the industrial level.‎