Surreptitious apple cider vinegar treatment of a melanocytic nevus: Newly described histologic features

Dynamics of Physicochemical Properties, Functional Compounds and Antioxidant Capacity during Spontaneous Fermentation of Lycium ruthenicum Murr. (Qinghai–Tibet Plateau) Natural Vinegar

Functional fermented fruit drinks are known worldwide for their health-promoting potential. Black wolfberry (BW) has high nutritional value, and its relative product development can be enriched through fermentation technology, so that its market might be broadened. Total acid, sugars, proteins, enzymes, anthocyanins, flavonoids, polyphenols, organic acids and DPPH free radical scavenging ability (DPPH) were tracked and determined by colorimetric method and HPLC during spontaneous fermentation of BW vinegar. The antioxidant capacity in vitro of BW vinegar was evaluated based on the dynamics of antioxidant contents and DPPH. The results showed that total acid continuously increased during fermentation, yet total sugar and reducing sugar shared a similar decreasing trend. The composition of samples differed in terms of total anthocyanins, total flavonoid, total polyphenol, total protein, superoxide dismutase (SOD), amylase, organic acids and DPPH through spontaneous fermentation. Functional compounds including total polyphenol, total flavonoid and three organic acids (γ-aminobutyric acid, lactic acid and gallic acid) played the main roles in antioxidation. Unexpectedly, SOD and ascorbic acid as antioxidants did not correlate with DPPH, but they were rich in the final products at 754.35 U/mL and 3.39 mg/mL, respectively. Generally, the quality of BW vinegar has been improved based on analyzing dynamics on functional compounds, organic acids and antioxidant capacity, which proves that BW vinegar obtained by spontaneous fermentation should be a potential source of fermented food with antioxidant effects for consumers.

Analysis of Selected Minerals in Homemade Grape Vinegars Obtained by Spontaneous Fermentation

Fruit vinegars are widely used as a spice and food preservative. They are considered as functional food, containing many bioactive compounds with pro-health benefits. Grape vinegars can be also a source of mineral compounds. Their quantity and diversity can be determined by environmental factors and growing conditions, such as temperature, mineral composition of the soil, heavy metal contamination, sunlight availability as well as grape variety and fruit ripeness stage. The aim of the study was to determine the content of minerals in homemade grape vinegars, obtained by spontaneous fermentation. Five different grape (Vitis vinifera L.) varieties were used in the study (Cabernet Cortis, Johanniter, Solaris, Souvignier gris and Prior). Moreover, the effect of sugar addition in the fermentation process on the mineral content was examined. The mineral content was determined using the ICP-OES method. Among the analysed samples, potassium was the most abundant element (936.07-1472.3 mg/L of vinegar). Comparative analysis showed that the content of Ca, Fe and Cr was significantly higher in vinegars prepared from red varieties than in white-coloured ones. In turn, vinegars prepared from white grape varieties contained statistically significantly higher content of potassium. Vinegar colour did not have a significant influence on the content of the remaining elements included in the analysis. Furthermore, statistical analysis did not reveal any significant differences in the content of the analysed minerals in any of the grape varieties used between the samples with and without sugar addition.

Analysis of Antioxidant Capacity and Antimicrobial Properties of Selected Polish Grape Vinegars Obtained by Spontaneous Fermentation

Nowadays, products of natural origin with health-promoting properties are increasingly more common. Research shows that fruit vinegars can be a source of compounds with antioxidant activity. Research on the total antioxidant capacity, total phenolic content, and antimicrobial properties against Staphylococcus aureus, Escherichia coli, and Candida albicans of grape vinegars were conducted. Moreover, gas chromatography was used to measure acetic acid content in the vinegars. The research material consisted of vinegars produced from five different grape varieties. For each variety, two variants were prepared: with and without the addition of sugar in the fermentation process. The highest antimicrobial activity against all micro-organisms was observed in vinegar produced from Solaris grapes with added sugar. The highest polyphenol content was observed in vinegar produced from the Prior grape variety with added sugar and the highest total antioxidant capacity is the Johanniter grape variety with added sugar. The vinegars examined in this study differed, depending on grape variety, in terms of antimicrobial properties, antioxidant capacity, total phenolic content, as well as acetic acid content. Sugar addition caused significant differences in the antioxidant capacity of vinegar samples.