Ricerc@Sapienza

The aceton-butyl-ethanolic fermentation process (ABE) is a biotechnological process that leads to the production of acetone, n-butanol and ethanol (ABE compounds) from glucose sources and amides by use of certain biomasses. The process was developed initially during the middle of the last century and suffers from decline due to the greater petrochemical production of products and the lowering of the costs of the sector. Nowadays, the ABE process is regaining great interest because the fraction with the highest concentration, i.e. n-butanol, is an excellent constituent for biofuels.

The reduction of alcohol content in wines has two main objectives, the former is decreasing the wines’ strength and the latter is producing new low alcohol beverages. To accomplish the latter, in this study, we focused on the dealcoholization of a white wine (cv Falanghina, 12.5 vol%) obtained from an ancient Italian grape variety that has recently aroused a renewed interest. It was dealcoholized at various alcohol content levels ranging from 9.8 to 0.3 vol% through the osmotic distillation process, and the main quality parameters of the obtained dealcoholized samples were evaluated.

This study investigated the effect of different degrees of dealcoholization on volatile compounds, phenols and sensory characteristics of red wine (cv. Montepulciano d’Abruzzo). The wine with an initial alcohol content of 13.2% v/v was partially dealcoholized by membrane process with a decrease of alcohol degree as follows: − 4.9; − 6.3; − 7.8, − 9.2 and − 10.5% v/v.

The demand of beverages with low or zero alcohol content is fast growing over the last years for health benefits of drinkers and more restrictive policies in alcohol consumption. Membrane processes are nowadays the most commonly used. They have undoubtedly led to improvements in quality, particularly for the low processing temperatures, but determined volatile compounds loss which in many instances resulted in unsatisfactory sensory quality.

Several studies on membrane reactors for hydrogen production have shown that the permeation of hydrogen may be inhibited by the competitive adsorption of one or more of the reactants. This adsorption-inhibition effect, often accounted for in rate expressions of catalytic reactions, may induce the existence of multiple steady state solutions. In this work we investigate the possible presence of bistability in membrane reactors.