Today in 1957, US Patent 2816031 A was issued, an invention of Wilhelm Eberhard Schultheis and Walter Specht, assigned to Ultra Technik G M B H, for his “Beer Brewing Process.” There’s no Abstract, although in the description it includes this summary:

We have found that the production of beer may be made more economical and that beers of superior qualities may be obtained by the application of ultrasonic waves, which term is generally understood to define waves whose frequencies are greater than those which affect the human ear, that is, greater than about 18,000 per second. The ultrasonic irradiation, called hereinafter sonoration, may be applied to various stages of the brewing process. For instance, hops in the presence of water or aqueous solutions, intermediary products such as mash, wort, glattwasser (last wort), or by-products, such as trub, may be treated, singly or severally, also in mixture with each other, with ultrasonic waves to obtain advantages.

As an ultrasonic generator, e. g. the immersion device type T 300a, rotation irradiator with high frequency generator (1000 kilocycles), built by Ultrakust G. m. b; H., Ruhmannsfelden, Lower Bavaria, may be used. The apparatus is preferably operated with full output, whereby it transmits about 300 watts ultrasonic energy to the treated batch.

The sonorat-ion is preferably carried out at elevated temperatures, e. g. between about 50 to 100 (3., which temperatures should be kept constant, and with at least temporary circulation of the treated solution.

A well known drawback of the conventional hopping process, where hops as such are added to the wort, is due to the fact that in the boiling process only about one-third or one-fourth, generally not more than 35 percent, of the bitter principal ‘(resins) contained in the hops pass into the wort, and that, in addition, considerable amounts, e. g. about 3 to 7 percent, of aid resins are precipitated during fermentation and storage.

According to the invention, these drawbacks are obviated by subjecting hops to sonoration in the presence of water or aqueous solutions, e. g. softened brewing water, wort, or last wort; hereby the valuable resins of the hops are dispersed in the extracting liquid without objection: able loss, and the thus obtained resin extracts are used for hopping the wort.

As the hop resins are difficulty soluble in water, only limited amounts of said resins can be dissolved in the water or aqueous solutions used as solvents. In addition, the dissolved resins readily precipitate again, particularly in the presence of absorbent substances, such as spent hops, trub, yeast, or carbon dioxide bubbles. The separation of the resins is further assisted by the fact that the pH of the sweet wort changes during fermentation from United States Patent 2 5.5 to about 4.5, which reduces the solubility of the resins.

We have found that ultrasonic waves have the elfect of producing a fine colloidal dispersion of the difficulty soluble resins in the extract, and at the same time, a stabilization against objection-able precipitation of said dispersed resins in the extract and later in the wort. We believe that this stabilizing action is due to colloidal substances which pass by the sonoration together with the resins into the aqueous liquid, and also to colloidal substance contained in the wort; This may explain the phenomenon that res-ins isolated by sonoration from the hops and dispersed in the aqueous phase can be concentrated in the extract; even in the acid range, to a considerable’ extent and that on addition of the resin extracts thus obtained to the boiling wort objectionable precipitation of resins is substantially avoided. Therefore, the resins are essentially retained in the wort and do not pass, to the extent experienced heretofore, into the trub or during fermentation into the so-called curls or into the yeast.

The extraction of the resins by scnoration may be carried out separately in a metal vessel of a suitable size for the hatch, e. g. in the hop strainer available in breweries, and the resin extract thus obtained will be admixed to the wort in suitable amounts. For instance, we may mix the allotted amount of hops with the extracting liquid, which has been heated to about 50 to 60 C. or even higher, and first agitate the mixture, for instance by circulator, for several minutes to obtain swelling and only subsequently start the sonoration. As extracting liquid, we may use decarbonate’d brewing water, or the glattwasset (last wort) obtained by washing (sparging) the spent grains separated from the first wort, or even the first wort itself. The amount of liquid to be added to the hops depends on the desired concentration ratio between hops arid liquid. In determining the optimum working conditions, it must be taken into account that the maximum extraction effect is not only dependent on said concentration ratio, but also on the nature and composition of the extraction liquid, the pH value, the extraction temperature, the ultrasonic intensity and the sonoration time. Our experiments were carried out at a temperature of about 5060 C. and the temperature was kept constant throughout the extraction period. Under these conditions, a sonoration period of about one hour lproved generally to be sufficient; sometimes it was necessary to apply a somewhat longer sonoration, e.g. up to two hours, in order to obtain optimum results. The extraction by means of sonoration may, however, be carried through also at higher temperatures, e. g. between 60 and C. with a shortened sonoration.

After completion of the extraction, the resinous extract may be separated from the spent hops, e.g. by filtering with suction, and separately processed.

Today in 1985, US Patent 4557186 A was issued, another invention of Christopher J. L. Brown, assigned to Bowmans Brewer, Ltd., for his “Brewing Apparatus.” Here’s the Abstract:

Brewing apparatus for batch brewing beer or ale comprises a fermentation vessel 1 in which a fermentable liquor is contained, a float hydrometer 11 and a sensor 12 for monitoring downward displacement of the hydrometer 11 as the specific gravity of the liquor reduces due to fermentation. The sensor 12 includes means for providing a signal in a controller 3 at a desired specific gravity to indicate completion of the required fermentation and the controller 3 is operable to control automatic transfer of the fermented liquor to a maturing vessel 4 and, after a predetermined time interval to a barrel or the like.

Today in 1968, US Patent 3415654 A was issued, another invention of Robert E. Zinn, assigned to Falstaff Brewing Corp., for his “Deep Vat Fermentation of Beer.” There’s no Abstract, although in the description it includes this summary:

This invention relates to an improved process for making beer, and to apparatus for carrying out the process. By the term beer is meant the various fermented malt beverages commonly included within that term, e.g., lager, ale, bock, porter, and stout. The fermentation of malt beverages is similar in many respects to fermentations in general; however, the consumption of the product by humans to satisfy thirst and for pleasure imposes unique and severe organoleptic criteria on the product.

It has now been found, in accordance with the present invention, that the fermentation of beer, to produce a highly acceptable product, can be carried out advantageously without the use of cellars and in thermally insulated and temperature-controlled individual tanks which provide the requisite greater beer depth and thus the greater foam depth. Despite the greater static pressure in the brew at these greater depths, the normal course of yeast-wort fermentation can unexpectedly be achieved, although hitherto it has generally been considered impossible or undesirable. Additionally, a volume of fermenting beer confined to a deep tank has a smaller surface area exposed to air than the same volume in a shallow tank. Preferably, the reciprocal ratio of surface area to the volume of liquid should be at least 20, and may exceed 60 or more. It will be noted that depth alone controls the surface area to volume ratio of the beer liquid.

A principal object of the present invention is therefore to provide a method of and apparatus for deep fermentation of beer with improved control of foam removal.

It is an object of the invention to provide a process of deep fermentation where the reciprocal ratio of surface area to the volume of liquid is at least 20. It is another object of the invention to provide a deep fermentation process wherein the reciprocal ratio of surface area to volume of liquid exceeds 40.

The object of this invention is attained by providing one or more deep fermentation tanks or fermenters of sufficient size to provide a beer depth of at least 20 feet, each tank being jacketed with suitable temperature control means adequate to assure the desired temperatures within the tanks. These tanks are supplied with wort and yeast and other conventional ingredients prepared in the usual fashion for supplying to beer fermentation tanks. Provisions are also made for thoroughly mixing the ingredients as fed to the fermentation tanks, and preferably also for circulation of the contents of such tanks during fermentation, so that the yeast may be effectively distributed throughout the fermenting mass to provide complete uniformity, thus assisting in assuring desired taste characteristics of the fermented product. Each fermenter is provided with means for selectively removing foam from the brew surface.