Double batch cider distillation: Influence of the recycling of the separated fractions

This study aimed to analyse the behaviour of volatile compounds during double batch cider distillation to produce Calvados. More precisely, it allowed to analyse the influence of the recycling of the separated fractions to manage the cuts according to the quality target. 700 L of cider were distilled with a 115 L Charentais still and 28 congeners were quantified into 65 samples from nine cider and two brouillis distillations. Most of alcohols were totally recovered into the heart of the second brouillis distillation, except 2-phenylethanol recovered at 5.4% because of its low volatility. For the same reason, esters as 2-phenylacetate, ethyl 2-hydroxypropanoate and diethyl butanedioate were significantly lost in the residues. Stopping distillations beyond 2 %v/v would increase their recovery but at an increasing cost. Other compounds are strongly concentrated in the head fractions. Among them, some such as ethyl acetate and acetaldehyde have negative impact on quality, while others such as ethyl decanoate and ethyl hexanoate bring floral notes. As these positive compounds are less concentrated in the head fraction of brouillis distillation than cider distillation, it is best, if negative compounds must be eliminated, to choose to extract head from brouillis distillation. Other possibility is to limit production of negative compounds.