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In this study, physicochemical, interfacial and emulsifying properties of Retama reatam and guar galactomannans were comparatively investigated. The results showed that Retama reatam galactomannan is mainly composed of total carbohydrates (95.52%) and lower protein contents (0.87%). The sugars identified were mannose (Man) and galactose (Gal), with a Man:Gal ratio of 1.85 compared to guar gum (1.83). The results of thermal properties indicated were transition temperature (Tg) and melting temperature (Tm) very similar to those of the guar gum. Moreover, results also revealed that there is no significant difference in terms of equilibrium interfacial tension of Retama reatam gum at 10 and 20°C. Moreover, preliminary tests show that stable oil-in-water nanoemulsions may be formulated using Retama reatam gum. Therefore, measurement of mean oil droplet diameter d after heating at 80°C, shows that stable nanoemulsions may be formulated using Retama reatam galactomannan. Further in vivo experiments confirmed that Retama reatam gum can reduce the glycemic index of starchy foods and inhibit the surge of postprandial blood glucose level.

In this study, response surface methodology, based on Box-Behnken design, was used to optimize the extraction conditions of protein isolate from the defatted seeds of jujube (Zizyphus lotus L.). This research focused on the effect of extraction temperature (30–50 °C), mixing time (15–75 min), pH (6.0–10.0), and solvent to solid ratio (15:1–35:1 v/w) on the extraction yield of jujube seed (Z. lotus L.) protein. The pH, mixing time and extraction temperature were the most significant (p

The present study was undertaken to determine the physicochemical, biochemical, and antioxidant activities of Tunisian honey samples. All the extracted honey samples appeared to con- form to the European Legislation (EC Directive 2001/110) for all parameters. Mint honey, for instance, possesses significant pH value (p < 0.05), invertase activity, water, and protein contents. In addition, this study demonstrates that the color of the Tunisian honeys is highly variable and ranges from pale yellow to dark brown. The total phenolic, flavonoid and carotenoid contents sig- nificantly vary (p < 0.05). The highest values were found in mint honey, which has a very dark color. Correlations between the analyzed parameters are statistically significant (p < 0.05). The DPPH radical scavenging activity of rosemary honey was determined as lower (p < 0.05) than the other analyzed honey samples. Yet, the highest activity was detected in mint honey. The results suggest that Tunisian honeys could be beneficially used as a functional or nutraceutical substance as they prevent or moderate oxidative stress-related diseases.

This study investigated the physicochemical, rheological and textural properties of nine types of honey from different regions of southern Tunisia. Principal component and cluster analyses were used to classify the honeys into groups. The physicochemical results (water, proteins, total soluble solids, pH, free acidity, water activity, electrical conductivity, invertase activity, Hydroxymethylfurfural (HMF), vitamin C, lycopene and anthocyanins) were in accordance with those of the standards Established by the Codex Alimentarius. The invertase activity varied from 62.58 units/kg to 110.24 units/kg. The HMF values of the different types of honey ranged from 11.48 mg/kg in prickly pear honey to 25.56mg/kg in heather honey. Anthocyanin contents, lycopene and vitamin C contents ranged between 8.38 and 24.86 μg/L, 1.08 to 6.17 mg/kg and 30.71 to 129.38 mg/kg, respectively. The flow test confirmed the Newtonian behavior of all honeys, and their textural properties had very high extrusion forces varying from 113.50 g to 131.05 g. Cluster analysis (CA) and the biplot generated through PCA recognized four groups of honeys based on either the physicochemical parameters or textural attributes and only three groups based on color and sugar.

The present study was undertaken to determine the physicochemical, rheological, and thermal properties of six types of Tunisian honey samples from various floral origins (eucalyptus, orange, thyme, mint, rosemary, and horehound). All the honey samples exhibited non-Newtonian behavior at a shear rate ranging between 0.01 and 500 s–1, with the highest levels of viscosity (µ) being observed for thyme, followed by eucalyptus, rosemary, mint, orange, and horehound honeys, respectively. The effect of temperature on the dynamic viscosity of the samples followed an Arrhenius-like pattern, with activation energy values ranging from 21.23 to 34.91 kJ/mol. The results from oscillatory rheology analysis also revealed that the loss modulus predominated over the storage one in the whole frequency range. As determined by differential scanning calorimetry, the glass transition (Tg) and melting temperatures of the Tunisian honey samples varied between –41.55 and –47.06 °C and between 197.9 and 221.1°C depending on their s...