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In this work, different aspects of particles size distribution in filtered beer were investigated. The utilisation of commercial cellulase or protease formulations influenced significantly the stability of filtered beer. By using Photon Correlation Spectroscopy (PCS) untreated beer samples at 6 and 20°C showed good "chill" stability, while the samples treated with exogenous enzymes showed a significant modification in the particles size distribution and reduced colloidal stability. The particles size distribution in the filtrate appeared to be related to the decrease of the cut-off size of the membrane and of the flux from the membrane. As reported, the largest particle size diameter flowing through the membrane decreased in each type of sample over the course of the filtration, due to the fouling of the filtering media. The results allowed confirmation that at the beginning of the filtration trials the main fouling cause was the decrease of the pores size within the membrane structure, more than cake formation over the membrane surface, although this second effect prevailed after a certain time.

BACKGROUND: This paper presents a multivariate approach to investigate the influence of barley variety, timing of nitrogen fertilisation and sunn pest infestation on malting and brewing. Four spring and two winter barley varieties were grown in one location in southern Europe. Moreover, one of the spring varieties was infested with sunn pest, in order to study the effects of this pest on malting quality, and subjected to different nitrogen fertilisation timing regimes. The samples were micromalted, mashed, brewed and analysed.

Legumes are very rich in phytochemicals and in particular isoflavones. In this work we have developed techniques to get the brewing craft beers made with the addition of Umbrian legumes (chickling and lentils), to verify if the healthy and nutritional characteristic of these product change. The results obtained show that probably during the processes of cooking and fermentation a transfer of the biologically active substances from the “special ingredients” to the finished beer takes place. From healthy and nutritional characterization of the beers important results emerged: an interesting mineral profile and a large content of molecules with antioxidant activity like phenolic compounds (350–630 mg/L). It should also be noted that within the group of phenolic compounds present in these beers were also found interesting amount of isoflavones in particular genistin and daidzin, which in addition to being powerful antioxidants have other beneficial effects and therefore can act in the prevention of cancer, inflammatory, cardiovascular, postmenopausal, cognitive, and immune diseases.

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