Seventy-eight samples of southern Italy honey from five different floral origins (chestnut, eucalyptus, citrus, multifloral and sulla) were screened to quantify the polyphenol and metal contents, evaluate the antioxidant activity and determine the correlations between the parameters analysed. The average polyphenol content was 12.06 mg gallic acid equivalent per 100 g honey and 7.92 mg quercetin equivalent per 100 g honey, for total phenolic and flavonoid contents, respectively. The antioxidant activity ranged from 58.40% (eucalyptus honey) to 60.42% (chestnut honey) in the ABTS assay, from 152.65 lm Fe (II) (citrus honey) to 881.34 lm Fe (II) (chestnut honey) in the FRAP assay, and from 54.29% (citrus honey) to 78.73% (chestnut honey) in the DPPH assay. Fe and Zn were the most abundant among the tested metals, while Cd, Co and Mo were those less present. Chestnut honey presented the highest polyphenol content, antioxidant activity and metal content. The correlations between the analysed parameters were statistically significant (P < 0.05). The correlations between metal content and both total phenolic and antioxidant activities were particularly interesting, suggesting a relationship between metal and polyphenol contents in honey.

Summary The aim of our study was to identify and quantify the phenolic acids, flavonoids and vitamin C and to evaluate the antioxidant activity in ninety Italian honeys of different botanical origins (chestnut, sulla, eucalyptus, citrus and multifloral). The results showed that total phenolic and flavonoid contents varied from 11.08 to 14.26 mg GAE per 100 g honey and from 5.82 to 12.52 mg QE per 100 g honey, respectively. HPLC–UV analysis showed a similar but quantitatively different phenolic profile of the studied honeys. Vitamin C is present in all samples. Multifloral honey showed the highest amount of the detected total phenolic compounds and the highest vitamin C content. The DPPH value varied from 55.06 to 75.37%. Among the unifloral honeys, chestnut honey presented the highest levels of phenolic acids, flavonoids and vitamin C, which are closely associated with its high antioxidant activity. The results show that honey contains high amount of biologically active compounds, which play an important role in defining the nutraceutical quality of the product, and that the distribution of these compounds is influenced by the botanical origin.

The aim of this work was to investigate on the functional features of a donkey milk probiotic berevage as a novel food. Particularly, it was to study the decrease of lactose content and the antioxidant activity of standard yogurt (YC) and probiotic yogurt (YP; Lactobacillus acidophilus, Lactobacillus casei) from donkey milk during the storage up to 30 d at 4 ºC. The evolution of lactose content using enzymatic-spectrophotometric kits was analyzed. Antioxidant activity of yogurt was measured using 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), ferric reducing antioxidant power (FRAP), and thiol assays. Parallel consumer sensory studies were carried out as consumer test in order to gain information about the impact of these novel fermented beverages on sensory perceptions. The statistical analysis has shown significant effect of studied factors. The results showed that the lactose content gradually decreased during storage in both yogurts, reaching values of 2.36% and 2.10% in YC and YP, respectively, at 30 d (P < 0.05). During storage of both yogurt types, the antioxidant activity increased, but YP showed a higher antioxidant activity than YC. The results suggest that the antioxidant activity of yogurt samples was affected by cultures of lactic acid bacteria (LAB). We conclude that the fermented donkey milk could be configured as health and nutraceutical food, which aims to meet nutritional requirements of certain consumers groups with lactose or cow milk protein intolerance.

The aim of this work was to investigate the antioxidant activity of yogurt made from the milk of 2 breeds-Italian Brown and Italian Holstein-characterized by different casein haplotypes (αS1-, β-, and κ-caseins) during storage up to 15 d. The casein haplotype was determined by isoelectric focusing; antioxidant activity of yogurt was measured using 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid). The statistical analysis showed a significant effect of the studied factors. Antioxidant activity increased during storage of both yogurt types, but yogurt produced with Italian Brown milk showed higher antioxidant activity than those produced with Italian Holstein milk. A high scavenging activity was present in yogurts with the allelic combination of BB-A(2)A(2)-BB. The results of this study suggest that the genetic type and the haplotype make a significant contribution in the production of yogurts with high nutraceutical value.

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