Amber ale beer enriched with goji berries - The effect on bioactive compound content and sensorial properties.

Goji berries, traditionally used in Chinese medicine, are nowadays gaining popularity in the Western world. Efforts are made to enlarge the offer of goji containing foods. In this study, goji berries were added to ale type beer at different stages of the production process in order to develop a beverage with desirable sensory characteristic and high antioxidant capacity. The obtained beers differed significantly in terms of appearance, taste and antioxidant activity. Consumers preferred beers to which goji berries were added at the beginning of the brewing process. These beers were also characterized by lower turbidity, high color intensity, caramel- and coffee-like taste, high antioxidant activity and high content of bioactives such as rutin and 2-O-ß-d-glucopyranosyl-l-ascorbic acid. To conclude, an addition of goji berries to traditional brewing process creates a perspective to enlarge the range of goji containing foods.

A new chemical tool for absinthe producers, quantification of α/ß-thujone and the bitter components in Artemisia absinthium.

The concentrations of α/ß-thujone and the bitter components of Artemisia absinthium were quantified from alcoholic wormwood extracts during four phenological stages of their harvest period. A solid-phase micro-extraction method coupled to gas chromatography-mass spectrometry was used to determine the concentration of the two isomeric forms of thujone. In parallel, the combination of ultra-high pressure liquid chromatography and high resolution mass spectrometry allowed to quantify the compounds absinthin, artemisetin and dihydro-epi-deoxyarteannuin B. This present study aimed at helping absinthe producers to determine the best harvesting period.

Quantification of the production of hydrogen peroxide H2O2 during accelerated wine oxidation.

Understanding how wines react towards oxidation is of primary importance. Here, a novel approach was developed based on the quantitative determination of the key intermediate H2O2 produced during accelerated oxidation by ambient oxygen. The assay makes use of the conversion of the non-fluorescent Amplex Red substrate into a fluorescent product in presence of H2O2. The total production of H2O2 during 30min was quantified with low within-day and between-day variabilities. Polymerized pigments, but not total polyphenols, played a major role in the determination of H2O2 levels, which were lower in white wines than red wines. H2O2 amounts also increased with temperature and the addition of metal ions, but did not depend on the concentration of many other wine constituents such as SO2. H2O2 levels did not correlate with anti-oxidant properties. We believe that this novel methodology might be generically used to decipher the oxidation mechanisms in wines and food products.