Storage temperature and UV-irradiation influence on the ergosterol content in edible mushrooms

International audienceErgosterol (5,7,22-ergostatrien-3 beta-ol) and ergosteryl derivatives from different genera of edible mushrooms were separated and quantified by an isocratic reversed-phase high performance liquid chromatography (HPLC) method. The technique allowed a rapid separation of free ergosterol and two ergosteryl derivatives occurring in mushrooms. The ergosterol content varied considerably depending on the fungus. Thus, the species Agaricus bisporus and Hygrophorus marzuolus presented high quantities of ergosterol (6.4-6.8 mg/g, dry matter) followed by Pleurotus ostreatus, Calocybe gambosa, Lentinus edodes, and Boletus edulis (3.3-4.0 mg/g). In contrast, other species, such as Cantharellus cibarius, Lactarius deliciosus and Craterellus cornucopioides, contained significantly lower ergosterol amounts (0.2-0.4 mg/g). Two ergosteryl derivatives were found in mushrooms and also the content depended on the fungus. The stability of ergosterol, in terms of the formation of ergosterol peroxide, was evaluated under different storage temperatures and UV radiation. The lower the temperature (-20 degrees C) and the radiation time (10 min), the lower ergosterol oxidation was observed

Distribution Patterns of Polyphenols and Alkaloids in Instant Coffee, Soft and Energy Drinks, and Tea

previously developed method of HPLC-DAD-Fl has been used for the determination of phytochemical profiles in different types of drinks: instant coffee, soft drinks, energy drinks, and different types of tea (green, white, black, and red tea). Using data on the concentrations of 20 main phytochemicals (phenolic acids, flavan-3-ols, flavonols, flavones, and alkaloids) it was possible to identify most of the sample types. Chlorogenic and caffeic acids and caffeine are the main target compounds in instant coffee; in soft and energy drinks, only caffeine was found. Tea has a more complex phytochemical composition. Unfermented tea is mainly composed of flavan-3-ols and alkaloids, with a high caffeine concentration. Black tea is composed of alkaloids and low levels of flavan-3-ols, which are affected by oxidative reactions during the fermentation. Flavonols are present in lower concentrations in all kinds of teas. The identified phytochemical distribution patterns were used to correctly differentiate instant coffee, soft drinks, energy drinks, unfermented tea and fermented tea (within fermented tea, black tea from red tea can also be differentiated)

In vitro anti-inflammatory activity of phenolic rich extracts from white and red common beans

International audienceAccording to epidemiological evidence, diets rich in fruits and vegetables can reduce the incidence of several chronic diseases that share an inflammatory component. These protective effects are attributed, in part, to the occurrence of different antioxidant components, mainly phenolic compounds. Our aim was to characterise phenolic composition, and to determine antioxidant and anti-inflammatory activities of phenolic rich extracts obtained from two kinds of common beans, white kidney beans (WKB) and round purple beans (RPB). Phenolic acids were the predominant component in WKB extracts, whereas RPB extracts presented higher concentrations of phenolic compounds, mainly catechin derivatives, proanthocyanidins and catechin glucoside. In addition, RPB extracts showed higher antioxidant capacity and higher anti-inflammatory activity by the reduction of NO production and cytokine mRNA expression of LPS stimulated macrophages. These results suggest that common bean extracts may be used as a source of anti-inflammatory agents as well as a dietary complement for health promotion

High hydrostatic pressure treatment and storage of soy-smoothies: Colour, bioactive compounds and antioxidant capacity

Bioactive compounds lycopene, α-, β- and ε-carotenes, ascorbic acid, chlorogenic, p-coumaric, caffeic, hesperidin, narirutin, genistein, daidzin, daidzein, catechin and epicatechin were quantified in order to provide new information on high pressure (HP) processing (550 and 650 MPa/3 min/20 °C) compared to pasteurization (80 °C/3 min) in a multifruit-soymilk smoothie. Antioxidant activity (FRAP and DPPH), colour differences and storage effects (45 days/4 °C) were also investigated. HP maintained better original colour (ΔE< 2.82) than pasteurization (ΔE = 3.70), and did not modify the content of bioactive components (α- and ε-carotenes, ascorbic acid, total polyphenols); it even increased the concentration of lycopene and β-carotene and had higher antioxidant capacity than in heat-treated samples. Most remained quite stable under cold storage. About 55% of the ascorbic acid, the main compound relating to antioxidant capacity (r = 0.7399 for FRAP and r = 0.8944 for DPPH), was retained at the end of the storage period. © 2016 Elsevier Ltd

Contribution to the aroma of white wines by controlled Torulaspora delbrueckii cultures in association with Saccharomyces cerevisiae

Although the positive role of non-Saccharomyces yeasts on the overall quality of wine is encouraging research into their oenological potential, current knowledge on the topic is still far from satisfactory. This work analyzes the contribution of starter cultures of Torulaspora delbrueckii, inoculated sequentially with Saccharomyces cerevisiae (multi-starter fermentation), on the fermentation and aromas of two different white style wines, i.e., dry and sweet wines. Chemical analysis of Soave and Chardonnay wines (dry wines) showed that multi-starter fermentation greatly affected the content of several important volatile compounds, including 2-phenylethanol, isoamyl acetate, fatty acid esters, C4\u2013C10 fatty acids and vinylphenols. Moreover, strain-specific contributions have been shown by testing two different T. delbrueckii strains. Evidence of the positive impact of T. delbrueckii activity on wine quality was also demonstrated in Vino Santo, a sweet wine. Due to its low production of acetic acid, this non-Saccharomyces yeast is recommended for the fermentation of high sugar grapes. T. delbrueckii also influenced the content of different variety of chemical groups, including lactones. From a sensory perspective, all wines produced by multi-starter fermentation have greater aromatic intensity and complexity than wines resulting from a monoculture fermentation. These results emphasize the potential of employing T. delbrueckii, in association with S. cerevisiae, for the production of white wines of different styles with improved and enhanced flavour