Pure Products Volume 7 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1911 Excerpt: ... of the condenser, being led into a Florentine flask which is connected with the still by means of a constant level syphon. Under these conditions a reflux distillation takes place, whereby the contents of the still not only remain at the same level, but remain at the same temperature. The process of the reflux distillation is explained as follows: The aroma of the peels is dissolved in the distillate, together with the turbidity-forming substances, the alcohol content of the liquid in the still having been reduced to about 30 volume per cent. When this liquid is distilled a high percentage distillate (about 85 per cent. of alcohol by volume) passes over, and with it goes the aroma substances, and both are condensed to liquid in the condenser. On condensation, the alcohol content is not strong enough in order to hold the terpenes and other turbidity-forming substances in solution. These, therefore, collect quantitatively as an oily layer on the upper surface of the liquid in the Florentine flask, while the aroma substances for the most part remain in solution and are returned to the still. This process is kept up until the oily layer in the Florentine flask does not perceptibly increase, a point which can be readily recognized after a little experience. The quantity of the sesquiterpenes so obtained is variable, but not large. After the removal of these oils the contents of the still are now distilled off to zero proof and the distillate is reduced with water to 35 per cent. alcohol. A milky turbidity will result, and this is to be removed by filtering through fuller's earth. The resulting product is the basis of the finished essence. In amount, after filtering, it will be about 150 liters. The filtrate is to be weighed and sufficient distilled water added ...