YEAST, ARTIFICIAL. Mix two parts, by weight, of the fine flour of pale barley malt with one part of wheat flour. Stir 50 pounds of this mixture gradually into 100 quarts of cold water, with a wooden spatula, till it forms a smooth pap. Put this pap into a copper over a slow fire; stir it well till the temperature rise to fully 155° to 160°, when a partial formation to sugar will take place, but this sweetening must not be pushed too far ; turn out the thinned paste into a Bat cooler, and stir it from time to time. As soon as the wort has fallen to 59° Fehr . transfer it to a tub, and add for every 50 quarts of it 1 quart of good fresh beer yeast, which will throw the wort into brisk fermentation in the course of 12 hours. This preparation will be good yeast, fit for bakers' and brewers' uses, and will continue fresh and active for 3 days. It should be occasionally stirred.
When beer-barm has become old and flat, but not sour, it may be revived by mixing with every quart of it a small po tato, boiled, peeled, and rubbed down into a paste. The mixture is to be placed in a warm situation, where it will speed ily show its renewed activity, by throw ing up a froth upon its surface. It must be forthwith incorporated with the dough, for the purpose of baking bread. When the barm has become sour, its acid should be neutralized with a. little powdered carbonate of soda, and then treated as above, when it will, in like manner, be revived. A bottle of brisk small beer may furnish ferment enough to form, in this way, a supply of good yeast for a small baking.
The German yeast employed by bakers in baking cakes and other fang bread, is made by putting the unterhele into thick sacks of linen or hempen yarn, letting the liquid part, or beer, drain away ; placing the drained sacks between boards, and exposing them to a gradually ingps ing pressure, till it mass of a thin effEesy consistence is obtained. This cake is
broken into small pieces, which are wrap ped in separate linen cloths ; these par cels are afterwards inclosed in wax-cloth, for exportation. The yeast cake may also be rammed hard into a pitched cask, which is to be closed air-tight. In this state, if kept cool, it may be preserved active for a considerable. time. When this is to be used for beer, the proportion required should be mixed with a quanti ty of worts at 60° Fahr., and the mixture left for a little to work, and send up a live ly froth, when it is quite ready for adding to the cooled worts in the fermenting back. YEAST, PATENT. Boil 6 ounces of hops in 3 gallons of water 3 hours ; strain it off, and let it stand 10 minutes ; then add half a peek of ground malt, stir it well up, and cover it over ; return the hops, and. put the same quantity of water to them again, boiling them the same time as be fore, straining it off to first mash ; stir it up, and let it remain 4 hours, then strain it off, and set it to work at 90°, with 3 pints of patent yeast ; let it stand about 20 hours; take the scum off the top, and strain it through a hair sieve; it will be then fit for use. One pint is suf ficient to make a bushel of bread. YENITE. A ferruginous silicate of lime, from Elba; named by Lclievre, its discoverer, in honor of the 'battle of. Jena. ZAFFRE. An impure oxide of cobalt, obtained by exposing the native arseni nret of cobalt broken into small pieces to I he action of heat and air in a reverberat ing furnace, by which its elements are oxidized, and the greater part of the ar senic driven off.