The Influence of Time and Storage Conditions on the Antioxidant Potential and Total Phenolic Content in Homemade Grape Vinegars.

Fermented foods have been an integral part of the cuisines of almost all cultures in the world. In recent years, they have gained ground again, mainly due to their potential health benefits. One such product is grape vinegar, which apart from characteristic taste, is also a source of compounds with antioxidant activity. The aim of the study was to determine the changes in the antioxidant potential and the content of polyphenols that occur during the storage of grape vinegar obtained by spontaneous fermentation. The research material consisted of vinegar made from different white grape varieties grown in Poland. For each variety, two variants were prepared: with and without the addition of sugar in the fermentation process. The antioxidant potential, polyphenol content, soluble solids content and pH were monitored both during the two-month fermentation process and the subsequent 6-months storage under various conditions. Storage conditions and time of the storage affected the antioxidant activity and polyphenol content. The content of these compounds was also influenced by the variety of grapes used as well as the method of vinegar preparation.

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.

Health Benefits and Chemical Composition of Matcha Green Tea: A Review.

Japanese matcha is a type of powdered green tea, grown in a traditional way. Shading of the plants during the growth period enhances the processes of synthesis and accumulation of biologically active compounds, including theanine, caffeine, chlorophyll and various types of catechins. Green tea contains four main catechins, i.e., (-)-epicatechin (EC), (-)-epicatechin-3-gallate (ECG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin-3-gallate (EGCG), of which the latter is the most active and abundant and matcha is their best condensed source. Due to its unique chemical composition and prized flavour, which sets it apart from other tea beverages, it is considered the highest quality tea. Its health-promoting properties are attributed to the high content of antioxidant and anti-inflammatory substances. Studies confirming the high antioxidant potential of tea beverages claim that it originates from the considerable content of catechins, a type of phenolic compound with beneficial effects on human health. Due to its potential for preventing many diseases and supporting cognitive function, regular consumption of matcha may have a positive effect on both physical and mental health. The aim of this review was to compile the health benefits of matcha tea. It is the first such review to be undertaken, and presents its main bioactive compounds in a systematic manner.

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.

Evaluation of Fluoride and Selected Chemical Parameters in Kombucha Derived from White, Green, Black and Red Tea.

Kombucha dates back thousands of years and is reported to have originated in East Asia. It is produced by fermenting tea with added sugar using SCOBY (symbiotic culture of bacteria and yeast). Its health benefits can be attributed to the metabolites produced during the fermentation process. Valuable ingredients of this fermented tea beverage include acetic acid, glucuronic acid, vitamins, enzymes, sugars and polyphenols. Tea, and consequently kombucha, contains numerous minerals, and one of them is fluoride. Under physiological conditions, fluoride plays a significant role in hard tissue mineralisation processes. However, even at low concentrations with long-term exposure, fluorides may accumulate in the body and cause a range of detrimental effects. Kombucha is traditionally brewed with black tea, but these days it is becoming increasingly popular to use other types of tea to make it, which may significantly affect its composition and health-promoting effects. The aim of the study was to evaluate the fluoride content in kombucha beverages derived from black, green, white and red tea. Fluoride content was measured at different time points during fermentation. The potentiometric method was used to determine the content of fluoride ions. It was demonstrated that kombucha is a major dietary source of fluoride (0.42-0.93 mg/L) and that the type of tea used has a significant effect on its chemical composition. Therefore, it recommended to make the beverage with white or red tea, due to the lowest fluoride content and ensure food safety.Graphical Abstract.

Irritable Bowel Syndrome Prevalence among Participants of Woodstock Rock Festival in Poland Based on Rome IV Criteria Questionnaire.

BACKGROUND: Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder (FGID), in which etiology and pathogenesis are not fully explored. There is an ongoing need for more population studies adhering to new ROME IV criteria. In the current study, which follows our previous investigation among participants of the Woodstock Rock Festival in Poland, we aimed to evaluate the prevalence of IBS and its relation to age, gender, education, and IBS type. METHODS: Rome IV criteria questionnaire was used to assess abdominal complaints of 386 participants of the Woodstock Rock festival 2018. RESULTS: Analyzed data revealed that Rome IV criteria were met by 42 participants (11.41%), 11 men and 31 women (p = 0.0028), with following types of IBS: IBS-M (mixed form) 55%, IBS-D (with diarrhea) 33%, IBS-U (unclassified) 10%, IBS-C (with constipation) 2%. No statistically significant correlation between IBS prevalence and age, gender, or education (p > 0.05) was found. CONCLUSIONS: The prevalence of IBS among major rock festival participants in Poland was high. Women met the criteria more often than men, which is consistent with global epidemiology for many years. Among participants of the Woodstock Rock Festival, the most frequent subtype was IBS-M, the rarest-IBS-C. There is a need of conducting cohort studies in bigger groups in our population.

Passiflora incarnata in Neuropsychiatric Disorders-A Systematic Review.

BACKGROUND: Stress is a natural response of the body, induced by factors of a physical (hunger, thirst, and infection) and/or psychological (perceived threat, anxiety, or concern) nature. Chronic, long-term stress may cause problems with sleep, concentration, and memory, as well as affective disorders. The passionflower (Passiflora incarnata) is a perennial plant with documented therapeutic properties. The literature data suggest that the passionflower itself, as well as its preparations, helps reduce stress and can therefore be helpful in the treatment of insomnia, anxiety, and depression. The objective of this systematic review was to evaluate Passiflora incarnata in terms of its neuropsychiatric effects. METHODS: The scientific databases PubMed, ClinTrials.gov, and Embase were searched up to 22 October 2019. The search identified randomized clinical trials describing the effects of Passiflora incarnata in neuropsychiatric disorders. RESULTS: The systematic review included nine clinical trials. The duration of the studies included in the analysis varied widely, from one day up to 30 days. Study participants were no less than 18 years old. In each of the papers, the effects of passionflower were measured by using a number of different tests and scales. The majority of studies reported reduced anxiety levels following the administration of Passiflora incarnata preparations, with the effect less evident in people with mild anxiety symptoms. No adverse effects, including memory loss or collapse of psychometric functions, were observed. CONCLUSION: Passiflora incarnata may be helpful in treating some symptoms in neuropsychiatric patients.