Molasses fermentation

Other acids (often as esters) have been found in fermented molasses. Usually these substances are products of bacteriological action and they are not normal constituents of unfermented molasses. Bauer" oil from the yeast fermentation of Cuban blackstrap consists chiefly of the ethyl esters of capric, lauric, myristic and palmitic acids.122 The fat from the scums of hot-room Louisiana molasses contained hexanoic (caproic) and octanoic (caprylic) acids.10 The occurrence of such volatile acids as propionic,128 butyric128 124 and valeric acids124 requires more adequate establishment. 

Aqueous solutions of these alcohols occur when sugar solutions are fermented and may be separated by distilling the mixtures. It is a common, economically valuable process for manufacturing potable liquors and for producing industrial alcohol from fermented molasses solutions or pulp mill wastes. One of the authors (A.Y.M.) reports that design and operation of these columns is hampered by lack of vapor-liquid equilibrium data, especially for making potable liquors, where small amounts of the alcohols other than ethanol greatly affect the flavor and, therefore, the products marketability. 

Our society now manufactures and consumes many distilled liquors. Scotch and bourbon whiskeys are made from beerlike preparations of grain. Rum is distilled from fermented molasses ... 

As the free sugar in many fruits, plants, and in honey, unit of sucrose and inulin As the free sugar in residue of fermented molasses... 

Rum Distilled from fermented molasses aged about three years 40-75... 

Rums are a distinctive beverage of this class in that they consist of the distillate from fermented molasses or other solution of sugarcane juice origin. So-called light or heavy rums are obtained depending on the type of sugarcane product that is fermented and the details of the distillation and maturation process used. 

Rum is made from fermented molasses. It contains from 45 to 55 per cent alcohol. The flavor of rum is largely due to the ethyl butyrate and ethyl formate which it contains. 

Another food industry residue that has been investigated is molasses, the residue left after the crystallization of sucrose from sugarcane juice. The material can be stored in its concentrated form for long time periods and can be diluted to the optimum sugar content prior to use. Normally, very little nutrient supplementation is required for the conversion of molasses. Afschar et al. (1991, 1993) found that K. oxytoca could ferment molasses at high concentrations. In one batch experiment, quantities of molasses as high as 280 g/L was converted to 118 g/L of 2,3-BD. 

Molasses appears to have potential value as a substrate for 2,3-BD production. Klebsiella oxytoca can ferment molasses at high concentrations. In one batch experiment, as much as 280 g/1 of molasses was converted to 118 g/1 of 2,3-BD and 2.3 g/1 of acetoin. These high concentrations are needed inasmuch as molasses is a relatively expensive substrate, and the separation costs of the final product may be difficult fi-om such a complex carbohydrate source (Afschar et al. 1991). 

Until World War 1 acetone was manufactured commercially by the dry distillation of calcium acetate from lime and pyroligneous acid (wood distillate) (9). During the war processes for acetic acid from acetylene and by fermentation supplanted the pyroligneous acid (10). In turn these methods were displaced by the process developed for the bacterial fermentation of carbohydrates (cornstarch and molasses) to acetone and alcohols (11). At one time Pubhcker Industries, Commercial Solvents, and National Distillers had combined biofermentation capacity of 22,700 metric tons of acetone per year. Biofermentation became noncompetitive around 1960 because of the economics of scale of the isopropyl alcohol dehydrogenation and cumene hydroperoxide processes. 

Citric Acid. By far the most extensively used food acidulant is citric acid (qv) [77-92-9] C HgO. This acid is favored because of its solubiUty, fresh flavor character, low cost, and low toxicity. It is commercially synthesized by fermentation (qv) of molasses hy Aspergillus niger (6). 

Fermentation Feedstock. Sucrose, in the form of beet or cane molasses, is a fermentation feedstock for production of a variety of organic compounds, including lactic, glutamic, and citric acids, glycerol, and some antibiotics. Lesser amounts of itaconic, aconitic, and kojic acids, as well as acetone and butanol, are also produced (41,51—53). Rum is made by fermentation of cane molasses. Beet and cane molasses are used for production of baker s and brewer s yeast (qv). 

Sucrochemistry. A wide range of fermentation and chemical products can be made from sucrose either per se or in juice or molasses. 

Molasses is also used as an inexpensive source of carbohydrate in various fermentations for the production lactic acid, citric acid, monosodium glutamate, lysine, and yeast (60). Blackstrap molasses is used for the production of mm and other distilled spirits. 

In the acid hydrolysis process (79—81), wood is treated with concentrated or dilute acid solution to produce a lignin-rich residue and a Hquor containing sugars, organic acids, furfural, and other chemicals. The process is adaptable to all species and all forms of wood waste. The Hquor can be concentrated to a molasses for animal feed (82), used as a substrate for fermentation to ethanol or yeast (82), or dehydrated to furfural and levulinic acid (83—86). Attempts have been made to obtain marketable products from the lignin residue (87) rather than using it as a fuel, but currently only carbohydrate-derived products appear practical. 

Fermentation of fmit juices other than grapes, principally apple juice, is the same as that in the production of grape wine. For the production of mm, cane molasses is diluted to a sugar concentration of 15—29% the sucrose, glucose, and fmctose is completely fermented within 36 h at 30—32°C. 

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