Solid-state fermentation of red raspberry (Rubus ideaus L.) and arbutus berry (Arbutus unedo, L.) and characterization of their distillates

The aim of the present study was to obtain two distilled alcoholic beverages from red raspberry and arbutus berry by solid-state fermentation and subsequent distillation of the fermented fruits. The mean concentrations of ethanol and volatile substances in the distillates from red raspberry (41.3 and 200.1 g/hL aa) and arbutus berry (44.3 and 267.1 g/hL aa) were higher than the corresponding minimum limits (38.5 and 200 g/hL aa) fixed by the European Council (Regulation 110/2008) for fruit distillates. In addition, the mean concentrations of methanol in the two alcoholic beverages (113.9 g/hL aa in case of red raspberry, and 320.5 g/hL aa in case of arbutus berry) were much lower than the maximum levels of acceptability that the aforementioned regulation fixed for red raspberry (1200 g/hL aa) and arbutus berry (1000 g/hL aa) distillates. These results showed that both fruits can be used as fermentation substrates for producing two alcoholic beverages with high quality, which are safe for the consumers without any repercussion to their health from methanol concentrations.