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The effect of an extreme heat processing on Zantaz honey samples was studied using a panel of physicochemical parameters, antioxidant activities and FTIR-ATR spectroscopy. Honey samples were heated at 121 °C for 30 min and the heat processing effect was confirmed indirectly through the assessment of hydroxymethylfurfural content, for which the values increased significantly (p < 0.01), and diastase activity, which was totally absent after the thermal processing. Besides, the effects of the heat on the antioxidant activities were diverse. Indeed, while the ability to scavenge 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid cation radicals (ABTS·+) and 2,2-diphenyl-1-picrylhydrazyl radicals was enhanced (p < 0.05 only for ABTS·+), after the heat processing, nitric oxide radicals scavenging activity was reduced drastically (p < 0.01). Regarding the chelating power, it was totally abolished following heating. Other activities showed no significant alteration. The initial values of antioxidant activities seem to be determinant in the changes occurring after the heat processing. Amongst the analysed parameters, following the heat processing, the honey colour was the variable where the influence of baseline values was the greatest. The spectral analyses confirmed that FTIR-ATR is a useful technique to discriminate the chemical differences occurring in honey after heat processing.

Honey with Bupleurum spinosum (zandaz) as a main pollen source has not been the subject of previous detailed study. Therefore, twelve Moroccan samples of this honey were subjected to melissopalynological, physicochemical and micro-biological quality characterization, as well as antioxidant activity assessment. From a quality point of view, almost all samples were within the limits established by Codex Alimentarius, and/or the European legislation. All samples presented predominance of B. spinosum pollen (more than 48%). Relatively high levels of trehalose (1.3–4.0 g/100 g) and elezitose (1.5–2.8 g/100 g) were detected. Those sugars, not common in monofloral honeys, could be used as na important factor to discriminate zandaz honey. Flavonoid content correlated positively with the honey color, melanoidin and polyphenol content, and negatively with the IC50 values of scavenging ABTS (2,2´-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) free radicals, while proline amount correlated negatively with IC50 values of nitric oxide scavenging activity and chelating power. This correlation supports the use of anti-oxidant activities as important variables for PCA (principal component analysis). Both components explained 70% from the given data, and showed certain homogeneity upon analyzed samples independent of the region, suggesting the importance of B. spinosum nectar in the resulting honey characteristics.

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This study aimed to characterize the pollen and physicochemical profiles, and to evaluate the anti-oxidant capacity of six samples of Moroccan honey. The pollen grains of Eragrostis spp. Were predominant in all samples (from a minimum of 46.5861.59% to 72.7262.43% as a maximum), exceeding the minimum (generally 45%) required for the monoflorality nomination of a honey sample, and suggestion a case of newly reported honey. The analyzed samples had low diastase activity and hydroxymethylfurfural (HMF) content. Potassium was the dominant element in practi-cally all samples, except the sample with the highest Eragrostis spp. pollen percentage, which showed sodium predominance. The honey color ranged from water white to light amber, and posi-tively correlated the concentrations of phenols, proline and the capacity for scavenging free radicals. However, great variability observed in all the analyzed parameters, and could not be explained by the variability of the Eragrostis spp. pollen percentage, which suggests a hypothesis of low concentrated nectar.