Low-alcohol beer (0.5-1.2% v/v ethanol) is a less common brewing industry output than standard beer but there is an increasing interest in this product, as evidenced by increased attention to health and safety and government policies on alcohol and diet. The main challenge in the production of low-alcohol beer is the achievement of a product as similar as possible to regular beer, particularly concerning the content of the volatile compounds. These compounds can be lost during the physical removal of alcohol by dialysis, reverse osmosis and vacuum rectification. Consequently, an alternative technique is the use of biological methods, which involve the employment of non-conventional yeasts. In this paper, 11 non-conventional yeast strains were tested for low-alcohol beer production. The strains used belonged to two different species: Saccharomycodes ludwigii and Zygosaccharomyces rouxii. The beer samples produced by these strains were analysed for their ethanol content and main volatile compounds. The S. ludwigii strains were more suitable for brewing low-alcohol beer, especially strain DBVPG 3010, which also showed a higher content of esters and a lower amount of diacetyl compared with previous reports. The Z. rouxii strains produced an ethanol and diacetyl content above the taste threshold. This screening project can be considered as a first step towards the production of low-alcohol beer by means of new selected non-conventional yeasts. Copyright

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The SPME-GC-MS analytical method optimized in this study is suitable for characterizing the volatile fingerprint of different beers, especially on the basis of the kind of fermentation (top, bottom or spontaneous), the method of production and the style of the beer.

The use of sprouts in the human diet is becoming more and more widespread because they are tasty and high in bioactive compounds and antioxidants, with related health benefits. In this work, we sprouted rapeseed under increasing salinity to investigate the effect on free and bound total phenolics (TP), non-flavonoids (NF), tannins (TAN), phenolic acids (PAs), and antioxidant activity. Seeds were incubated at 0, 25, 50, 100, 200 mM NaCl until early or late sprout stage, i.e., before or after cotyledon expansion, respectively. Sprouting and increasing salinity slightly decreased the bound fractions of TP, NF, TAN, PAs, while it increased markedly the free ones and their antioxidant activity. Further increases were observed in late sprouts. Moderate salinity (25–50 mM NaCl) caused the highest relative increase in phenolic concentration while it slightly affected sprout growth. On the contrary, at higher NaCl concentrations, sprouts grew slowly (100 mM NaCl) or even died before reaching the late sprout stage (200 mM). Overall, moderate salinity was the best compromise to increase phenolic content of rapeseed sprouts. The technique may be evaluated for transfer to other species as a cheap and feasible way to increase the nutritional value of sprouts.