Starting on page 276 of the PDF.
As I laid out in the preface, I propose, in this large section, to treat in a detailed manner the principal types of beer. I will describe to begin with their nature, and I will give, wherever possible, their composition. After which I will indicate the particular processes by which one can obtain them. But before that, I think it is useful to set out in summary the general classification that I have adopted, both to facilitate the understanding of the entire work and to simplify this work and avoid unneeded and tedious repetition.
As we have already seen, beer is an alcoholic beverage comprising gummy and sugary ingredients, aromatic and bitter ingredients, along with various salts and free acids, in widely varying proportions. Among the most important elements of this beverage are without doubt: alcohol, the extractive materials which come from floury or sugary substances, and the components of hops which comprise nearly the entirety of what we commonly call the extract of beer. As the quantities of alcohol and extract are highly variable across the different types of beer, and their proportions and ratios will serve to characterize and distinguish a fairly large number of types and varieties that have much in common with each other, I think it necessary, before describing the preparation of each of these in particular, to indicate here the average quantity of alcohol and extract contained in the principal types of beers which I will maintain for the reader.
[Table of quantities of alcohol and extract contained in the principal types of beers.]
From this table, one can see not only the great variation in alcohol and extract contained in the different sorts and qualities of beer, but also (and this is what I propose to remark on in particular here) the important variations that exist in the ratios of these two elements so essential to these beverages.
Thus, while the ratio of the quantity of alcohol to the quantity of extract contained in London Export Ale, when it is newly brewed, is from 7 to 6½ (much greater than 1), it is only about ½ for Bavarian beers, and only ⅓ for Double Beer from Diest when it is fresh, that is brewed between eight and fifteen days. Thus, quite often the distinctive characteristics of a type of beer depend less on the amount of alcohol and extract as on the ratio of these elements and the nature of the extractive materials. In effect, for the same types of beers, as we see in the table, there are generally some very significant variations in their absolute quantities, while for the same types or varieties, the ratio of the quantity of alcohol to the quantity of extract they contain in their normal state varies little. And if they vary much with the age of the beer, as is the case for a large number of types which change considerably in nature with maturation, each variant of a type behaves in substantially the same manner in the same circumstances. Thus, for example, Louvain, Peeterman, and Diest Beer which vary notably in strength, always have, however, the same taste, the same aroma, and the same fatty or unctuous and slightly opaque aspect which distinguish them from other beers. If made with the same first ingredients normally employed for their preparation, the two elements are found in the appropriate ratio. Whereas, all things being equal, if these ratios depart from the ordinary limits of these types of beers while they are in their normal states, that is, if the quantity of extract is not large enough in ratio to that of alcohol, these beers are moving away from the genuine type in question. To a more or less noticeable degree it is the same for all beers, but more particularly for beers prepared with large proportions of wheat, which, in their normal state, contain by weight more extract than alcohol, whereas for most beers made with pure and sprouted barley, the proportions of these two essential elements commonly in balance or nearly so.
If the proportions of alcohol and extract, and overall the ration that exists between these proportions, have a large influence on the distinctive characteristics of a type of beer, the nature of the ingredients that constitute the extract which it contains has — without doubt — an influence no less great; for the extract, it is said, is the body of the beer, containing always a certain number of diverse essences which often differ greatly in their proportions and their natures, which renders the taste and the composition of the beers very different, following the primary ingredients employed to prepare them: and this is easily understood.
Classification of Beers. — Some authors have classified beers according to their color, some according to their strength, and others according to their origins; but these classifications cannot teach us anything. Following what I just said, I believe that it is much more reasonable to classify them according to their nature, taking the raw ingredients from which they are made as the basis; this will facilitate, without doubt, their study, and will permit me to shorten a great many details in the descriptions of the diverse processes used in the preparation of each type of beer that I will have to provide for the reader.
There are, in a sense, infinite varieties of beer, and it can be said in a general manner that each country, each province, even each locality has its own particular species of beer; but a lot of these varieties differ only by often imperceptible or barely perceptible nuances, and can be reported as the same type or same species; thus I commit myself to describe the principal varieties. I will divide the different sorts of beers into three large categories: the first containing the different types of beers prepared only with barley malt, that is, in the composition of which there are no appreciable amounts of grains other than barley malt. I will consequently designate this first class or category under the name — also supported by usage — of barley beer_. I will give to the second category the equally significant name of wheat-brewed beers, including in this second class all beers into the preparation of which wheat, oats, rye, or buckwheat enter in appreciable quantities. Finally, in the third category, I will gather all the different types of beers which are prepared or can be advantageously prepared with corn (maize), rice, starch, potatoes, beets, and other roots.