Fermentation presses

Port wine is fermented in shallow receptacles of masonry in which the grapes are trodden and, after fermentation, pressed. Fermentation in Italy, Spain, and the south of France is carried out at 15° to 24° C., and is a top fermentation, but in Germany and with the finer French wines, a bottom fermentation is made at 5° to 12° C. At the higher temperature the fermentation takes from 3 to 8 days, and the wine produced is fiery, high in alcohol, and lacking in delicate aroma. At the lower temperature the first fermentation lasts a few weeks, but yields a wine of delicate flavour. When fermentation is complete, and the wine has become clear, all the yeast aud other suspended matters are deposited oil the bottom of the cask or vat, constituting the lees. From this the young wine is racked, i.e. decanted or siphoned off, and run into a clean cask. 

T. Tsunoda in Bioindustry Development Center (BIDEC), eds.. From Fermentation to Neir Biotechnology (in Japanese), Japan Science Society Press, Tokyo, Japan, 1989. 

Anticariogenicity. Sugar alcohols are not fermented to release acids that may cause tooth decay by the oral bacteria which metabolize sugars and starches (208). As a result, use of sugar alcohols in sugar-free chewing gum, pressed mints, confections, and toothpaste has been widely accepted. 

Wine. The earliest known wines were made in Iran about 5400—5000 BC (25). The species of grape used is unknown and may have been either the wild grape Fitis viniferus sylvestris or a cultivated precursor of the modem wine grape V. viniferus viniferus. The source of the yeast used, and the procedures used are completely unknown. In modem times, grapes (about 21—23% sugar) are pressed the liquid must is either separated and allowed to settle for 1—2 days (for white wines) before inoculation with yeast, or the whole mass is dkectly inoculated with yeast (for red wines). In either case, while the initial fermentation takes place, the carbon dioxide formed by fermentation excludes ak and prevents oxidation. White wines are transferred to a second fermentor (racked) near the end of fermentation and kept isolated from the ak while solids, including yeast, settle out, a process that requkes about six... 

Soybean-Based Cheese. In tofu cheese manufacture, the soybeans are cooked to give soy milk, then formed into a curd using calcium sulfate, and pressed to give tofu. The tofu is inoculated y ctinomucor elegans fermented, salted, and aged to form sufu (soft cheese) (17). This product is widely used ia the Orient and is gaining acceptance ia the United States. 

O. P. Ward, ed.. Fermentation Biotechnology Principles, Processes, Products, Vol. 1, Open University Press, Milton Keynes, 1989. 

A suitable means of scale-up for aerobic processes is to measure the dissolved oxygen level that is adequate in small equipment and to adjust conditions in the plant until this level of dissolved oxygen is reached. However, some antibiotic fermentations and the production of fodder yeast from hydrocarbon substrates have very severe requirements, and designers are hard-pressed to supply enough oxygen. 

In the manufacture of baker s yeast, the stock strain is inoculated into a medium that containing molasses and com steep liquor. The pH of the medium is adjusted to be slightly acidic at pH 4-5. The acidic pH may retard the bacterial growth. The inoculated medium is aerated during the incubation period. At the end, the cells are harvested by centrifuging out the fermentation broth, and they are recovered by filter press. A small amount of vegetable oil is added to act as plasticiser, and then the cell mass is moulded into blocks. The process is shown in Figure 1.2. 

Stanbury, P.F. and Whitaker, A., Principles of Fermentation Technology . Pergamon Press, New York, 1987. 

G. L. Solomons, Materials and Methods in Fermentation, Academic Press, London-New York 1969. 

W. C. Evans, Microbial Transformations of Aromatic Compounds, in D. Perlman, Fermentation Advances, S. 649, Academic Press, New York 1969. 

Calam C.T. (1987) Process Development in Antibiotic Fermentations, Cambridge Studies in Biotechnology, 4 (eds Sir James Baddiley, N.H. Carey, J.F. Davidson, I.J. Higgins W.G. Potter). Cambridge Cambridge University Press. 

ROBERTS E A H (1962) Economic importance of flavonoid substances Tea fermentation , in GeissmanT A, Chemistry of Flavonoid Compounds, Oxford, UK, Pergamon Press, 468-512. 

A red wine was obtained from Carignan noir grapes Vitis vinifera) harvested in 1991 at the INRA-Pech Rouge Experimental Station. Mature grapes were stemmed and crushed before fermentation (7 days at 28 °C) in presence of total grape berry cell wall material. The insoluble material was finally eliminated by pressing, 5 g/hL SO2 was added and the obtained red wine stored at 12°C. 

Barker HA (1961) Fermentations of nitrogenous organic compounds. In The Bacteria (Eds IC Gunsalus and RY Stanier), Vol. 2, pp. 151-207. Academic Press, New York. 

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