The American Practical Brewer and Tanner

by Joseph Coppinger

Beer, wine, cider, malt and molasses wash, and other product by distillation; spirit consists of these three elastic fluids or airs, in composition with various proportions of water. Water itself is a compound of vital and inflammable air; a proof of this, and of the indestructibility of matter, these two elastic fluids burned together, in certain proportions, and in a proper apparatus, reproduce water. By another chemical process, this very water is reducible to these two substances, vital and inflammable air; hence, we see, that all saccharine and fermentable matter, and their products, by fermentation, are composed of the same materials, and resolvable into the same elements.

It is scarcely necessary to give any definition of spontaneous fermentation, after what has been said on the subject; if it was, I would say it is that tendency which all fermentable matter has to decomposition, attended with intestine motion or ebullition, when sufficiently diluted with water, under a certain temperature of the atmosphere, the rapidity of which motion is always accompanied by an increase of temperature, or the change to a greater degree of heat generated within the body of the fermenting fluid, in proportion to the rapidity or augmentation of motion or ebullition excited. Fermentation produced by the addition of yest, or any other suitable ferment, in a fluid duly prepared, is governed by the same laws, and under the same influence of temperature, except when it is accelerated or protracted by the management of the operator, or by the changes induced by the influence of the atmosphere, rendered more or less subservient to his purposes, and produces a similar kind of spirit by distillation, possessing in common the properties of vinous spirit, or is converted to vinegar by the subsequent process of acetous fermentation, but much more productive in quantity and quality, so as to answer commercial purposes. In both spontaneous and excited fermentation, there is a similar escape of a large quantity of elastic fluid, or carbonic acid gas, with a considerable proportion of spirit, and some of the water of the fermented fluid. This gas is known to form a considerable part of mucilaginous substances, as sugar, molasses, honey, malt, and other saccharine and fermentable matter.

Although the doctrine of fermentation, as a science, does not enable us to alter the spontaneous course of nature; yet if, by the assistance of the instruments, and means recommended, we are enabled to foresee and provide for the changes induced by the alterations of the atmosphere, we can guard against the inconveniences in some cases, and make them subservient to our purpose in others; so as more securely to conduct the process in each to advantage; and that with unusual facility; complex as it at present appears: it will not only be a great improvement in the present mode of fermentation; but facilitate our progress to still greater improvements in the doctrine of fermentation. Therefore, the rule of our conduct, in these pursuits, should be to watch the operations of nature with the closest attention, and assist her when languid, and control her when too violent; that is, by spurring in one instance, and bridling in the other, and accurately and undeviatingly apply the means proposed in the manner recommended, until experience enables us to improve it; otherwise, we shall only admire, without improving or profiting by her choicest phenomena.

The motions of the planets, perplexed and intricate as they must have appeared in the infancy of astronomy, are now calculated and known with ease and precision.

Attenuation is a term not unaptly applied to fermentation, the property of attenuation being to divide, then dilute, and rarify thick, gross, viscid, and dense substances, in which some degree of fluidity is pre-supposed; it is, therefore, that kind of dilution or fluidity which is promoted by agitation, and very aptly applied to mark the progress of fermentation, which is itself the process of nature, for decomposing vegetable and animal substances under a convenient degree of fluidity; it exists in intestine motion, either spontaneous or excited, accompanied with heat, which, under certain limits, is proportioned to the vigour of the fermentation, which ends in the decomposition of one class of bodies, and the composition of another; and which may be instanced in the resolving saccharine substances into hydrogen, oxygen, and carbon, and the combining them into inflammable spirits, or alcohol, and inflammable acids or vinegar; to which may be added, the lower you attenuate, the lighter and more spiritous the fermenting fluid becomes; and that attenuation, which is the offspring of fermentation, like the parent process, has its bounds, and can only be conducted with certainty and advantage by the use of the hydrometer, thermometer, &c. In this only lies the difference between the old word fermentation, and the new word attenuation, every thing used as a ferment, or to promote fermentation, is attenuant. The tendency of the vinous process of fermentation is to evolve or disentangle the hydrogen of the fermenting fluid, and unite it, with the carbon and oxygen of the same fluid, into ardent spirit, wine, beer, or alcohol, which last is well known to be inflammable. The tendency of the acetous process of fermentation, is to involve or entangle the hydrogen and carbon of the fermented fluid, with a greater proportion of oxygen, into vinegar, which is uninflammable. The fixed air, or carbonic acid gas, so abundantly extricated during the vinous process of fermentation, which every one concerned in the process is presumed to be acquainted with, is either composed of hydrogen and oxygen, or is a composition of carbon and oxygen, on which philosophers are divided in opinion. As the result is the same with respect to the formation of wine, beer, and spirit, I shall enter into no controversial reasoning on this head, instead of which, I shall endeavour to point out the most effectual mode of saving and profitably applying it, and the other elements, in the composition of wine, beer, spirit, and acid.

As in fermentation, spontaneous or excited, there is a sensible escape of carbonic acid gas, or fixed air, it may not be improper to note, that fermentable, or saccharine matter, consists of about twenty-eight pounds of carbon, eight pounds of hydrogen, and sixty-four pounds of oxygen, reducible into fixed, inflammable, and vital air, weighing one hundred subtile pounds in toto, or that every one hundred subtile pounds of saccharine matter consists of such proportions of these airs and gasses.

Attenuation is the result of a due resolution of the fermentable matter produced by excited fermentation, which divides mucilages, resolves viscidities, breaks down cohesions, generates heat and motion, extricates the imprisoned gasses, and, by frequent commixture, promotes the action and re-action of the component particles on each other, and by continually exposing a fresh surface and opposition of matter, brings them within the sphere of each other's attraction.

As their original attraction is weakened by heat and motion, their expansion is increased by repulsion; and as they revolve, and recede from each other in this way, they are fitted, by the change in their modification, to involve each other, and from new attractions combining with each other into new substances, according to affinity, under changes induced in their nature conducive to this end, which not being exactly known, cannot at present be fully defined. In every brewing, or preparation of saccharine fluid for fermentation, the following phenomena occur: first, heat is either disengaged or fixed: secondly, an elastic fluid is either formed or absorbed in a nascent state: these two indisputable facts form the uniform and invariable phenomena of fermentation, and may be admitted as an established axiom, that the proportions, extrication, and action of heat, with the fermentation and fixation of elastic fluids, during the process, are the foundation of the vinous products of the fermenting fluid. In conformity to so rational a theory, I have for many years regulated my practice, the result of which is the object of these papers. These, therefore, are the three great objects which should engage our attention; not only in fermentation, but in every similar process in chemistry, and are the fundamental principles of our doctrine. Fermentation being not only a decomposition of the fermentable matter, but of the water of the fluid also; and the fixed air formed during the process being composed of the hydrogen and oxygen of the fermentable matter, and the water of the fluid also, there is a perpetual decomposition and recomposition of that water, which gives fluidity to the whole mass, taking place during the continuance of the process, part of the hydrogen and oxygen of which escapes under the form of fixed air, for want of a proper substance being presented of affinity enough to absorb and combine with it into wine, beer, or spirit, or some other necessary assistance in heat, light, motion, oxygen, hydrogen, carbon, &c. or an intermedium to facilitate the formation of wine, beer, or spirit, in preference to fixed air. Fixed air, or carbonic acid gas, consists of about twenty-five parts of oxygen, and nine of carbon, devested of the mucilage and yest that rises with it. It should be recollected, that the decomposition of pyrites, the formation of nitre, respiration, fermentation, &c. are low degrees of combustion, and though it is the property of combustion to form fixed and phlogisticated airs, both the modes of doing it, and the quantity of the products, depend on the manner of oxygenating them in the changes brought about by the different modes of combustion, or fermentation in the vinous, acetous, and putrid process, which show the affinity between them.

Fermentation is a subsequent low combustion of the vegetable oxydes or grain, that has undergone a previous, but partial combustion, something like the slightly charring, or oxydating of wood or pit-coal, by which the oxygenation is incomplete in both, and rendered more complete in the former. An ultimate combustion of the fermentable matter employed, is found only in the putrid process of fermentation, which is a final or total decomposition of vegetable and animal substances, in the actual combustion or burning of wood, charcoal, or bones.

In the vinous process we have seen the escape of carbonic acid gas; in the acetous process there is a great escape of azotic gas, or phlogisticated air, from the decomposition of the air of the atmosphere consumed in this process, which consists of about two-thirds of azotic gas, and one third of oxygen gas,[3] ] the oxygenous part being absorbed in the acetous process, and azotic set free with more or less hydrogen and acetic gas, proportioned to the existing heat. If the heat is beyond a certain degree, a portion of the ethereal part of the new-formed acid escapes also.