Today in 1987, US Patent 4659662 A was issued, an invention of Win-Pen Hsu, assigned to J. E. Siebel Sons’ Company, Inc., for his “Batch Fermentation Process.” Here’s the Abstract:
Ethanol and fermented beverages such as beer or wine are produced in a batch process by contacting a fermentable substrate with yeast cells encapsulated within a porous, semi-permeable material. Contacting is carrier out in a vessel containing the substrate and a semi-permeable retaining means submerged in the substrate. Encapsulated yeast cells are maintained below the retaining means and in contact with the substrate during fermentation while being freely movable in a portion of the substrate. The retaining means is permeable to the substrate and is substantially impermeable to the encapsulated yeast cells. Preferably, the matrix encapsulating the yeast cells is an alginate gel.