Fermentation salts

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. 

Certik, M., and Slavikova, L. 2005. Biotransformation of oils to value-added products by fungal solid state fermentations. Salt Lake City UT Proceedings of 96th AOCS Annual Meeting Expo (pg. 18). 

The growth medium includes defined salts, complex nutrients, surfactants, and inducer. The salts are the typical fermentation salts, including potassium phosphate, ammonium nitrate, ammonium sulfate, calcium chloride, and magnesium sulfate [33]. The complex nutrients are most often 5 to 25 g L of corn steep liquor but can also include yeast extract. The surfactants are added to control or suppress foam formation. The surfactants used include commercial antifoams as well as soybean oil or palm oil. The inducers are proprietary to each manufacturer but will contain an inexpensive mixture of soluble and/or insoluble sugars. Some inducers used include milk whey, which contains lactose Solka floe cellulose or, sugar or paper mill waste streams. 

White crystals m.p. 162-164 C. ll can be prepared by the fermentation of sugar with the mould Aspergillus lerreus or by healing citra-conic anhydride with water at ISO C. Electrolysis of the potassium salt in solution gives allene. Itaconic acid is used as a comonomer in plastics its esters are polymerized to lubricating oils and plasticizers. 

C4HjOftK. Colourless salt, soluble boiling water occurs in grape juice, deposited as argol during fermentation. Used in baking powders (liberates CO2 with NaHC03). 

H02C(CH2)2C02H. Colourless prisms m.p. 182 C, b.p. 235°C. Occurs in amber, algae, lichens, sugar cane, beets and other plants, and is formed during the fermentation of sugar, tartrates, malates and other substances by a variety of yeasts, moulds and bacteria. Manufactured by the catalytic reduction of maleic acid or by heating 1,2-dicyanoethane with acids or alkalis. Forms an anhydride when heated at 235°C. Forms both acid and neutral salts and esters. Used in the manufacture of succinic anhydride and of polyesters with polyols. 

Citric Acid Separation. Citric acid [77-92-9] and other organic acids can be recovered from fermentation broths usiag the UOP Sorbex technology (90—92). The conventional means of recovering citric acid is by a lime and sulfuric acid process ia which the citric acid is first precipitated as a calcium salt and then reacidulated with sulfuric acid. However, this process generates significant by-products and thus can become iaefficient. 

Biopolymer Extraction. Research interests involving new techniques for separation of biochemicals from fermentation broth and cell culture media have increased as biotechnology has grown. Most separation methods are limited to small-scale appHcations but recendy solvent extraction has been studied as a potential technique for continuous and large-scale production and the use of two-phase aqueous systems has received increasing attention (259). A range of enzymes have favorable partition properties in a system based on a PGE—dextran—salt solution (97) ... 

Certain factors and product precursors are occasionally added to various fermentation media to iacrease product formation rates, the amount of product formed, or the type of product formed. Examples iaclude the addition of cobalt salts ia the vitamin fermentation, and phenylacetic acid and phenoxyacetic acid for the penicillin G (hen ylpenicillin) and penicillin V (phenoxymethylpenicillin) fermentations, respectively. Biotin is often added to the citric acid fermentation to enhance productivity and the addition of P-ionone vastly iacreases beta-carotene fermentation yields. Also, iaducers play an important role ia some enzyme production fermentations, and specific metaboHc inhibitors often block certain enzymatic steps that result in product accumulation. 

The sweet water from continuous and batch autoclave processes for splitting fats contains tittle or no mineral acids and salts and requires very tittle in the way of purification, as compared to spent lye from kettle soapmaking (9). The sweet water should be processed promptly after splitting to avoid degradation and loss of glycerol by fermentation. Any fatty acids that rise to the top of the sweet water are skimmed. A small amount of alkali is added to precipitate the dissolved fatty acids and neutralize the liquor. The alkaline liquor is then filtered and evaporated to an 88% cmde glycerol. Sweet water from modem noncatalytic, continuous hydrolysis may be evaporated to ca 88% without chemical treatment. 

The fermentation-derived food-grade product is sold in 50, 80, and 88% concentrations the other grades are available in 50 and 88% concentrations. The food-grade product meets the Vood Chemicals Codex III and the pharmaceutical grade meets the FCC and the United States Pharmacopoeia XK specifications (7). Other lactic acid derivatives such as salts and esters are also available in weU-estabhshed product specifications. Standard analytical methods such as titration and Hquid chromatography can be used to determine lactic acid, and other gravimetric and specific tests are used to detect impurities for the product specifications. A standard titration method neutralizes the acid with sodium hydroxide and then back-titrates the acid. An older standard quantitative method for determination of lactic acid was based on oxidation by potassium permanganate to acetaldehyde, which is absorbed in sodium bisulfite and titrated iodometricaHy. 

Tartaric acid [526-83-0] (2,3-dihydroxybutanedioic acid, 2,3-dihydroxysuccinic acid), C H O, is a dihydroxy dicarboxyhc acid with two chiral centers. It exists as the dextro- and levorotatory acid the meso form (which is inactive owing to internal compensation), and the racemic mixture (which is commonly known as racemic acid). The commercial product in the United States is the natural, dextrorotatory form, (R-R, R )-tartaric acid (L(+)-tartaric acid) [87-69-4]. This enantiomer occurs in grapes as its acid potassium salt (cream of tartar). In the fermentation of wine (qv), this salt forms deposits in the vats free crystallized tartaric acid was first obtained from such fermentation residues by Scheele in 1769. 

Starch is subject to fermentation by many microorganisms and, unless the mud is saturated with salt or the pH is >11.5, a preservative or biocide must be added if the mud is to be used for an extended period of time. The most common biocide until the mid-1980s was paraformaldehyde [9002-81-7]. This material has been largely replaced by isothia2olones (at 5—10 ppm cone) (74), carbamates, and glutaraldehyde [111-30-8]. Alternatively, the biocide may be incorporated during the processing of the starch and is present in the commercial product. 

Tolypomycins. The addition of small amounts of iron salts to the fermentation medium increases the production of tolypomycin Y (48) (7,203,204), the stmcture of which was arrived at by chemical degradation (205,206) and confirmed by x-ray crystallographic analysis (207) (Fig. 5). Mild acid hydrolysis of tolypomycin Y yields tolypomycinone [22356-23-6] (49, R = H), C27H42NO23, and tolyposamine [34174-76-0] C23H23NO2, (50). Further hydrolysis of tolypomycinone using acid yields tolyponone [24317-12-2] (51), which is also formed upon mild acid hydrolysis of rifamycia S. 

In baked products, salt controls fermentation (qv) by retarding yeast activity, preventing wild fermentation, important in making a uniform product. During pickle-making, salt brine is gradually increased in concentration, reducing the fermentation rate as the process proceeds to completion. Salt is also... 

Miso. Miso is a paste-like food having the consistency of peanut butter. It is made by fermenting cooked soybeans and salt with or without a cereal such as rice or barley (92). It is used as a base for soups in Japan, and as a seasoning in southern and eastern Asia. It is produced on a small scale in the United States. 

Further efficient fermentative methods for manufacture of riboflavin have been patented one is culturing C. famata by restricting the carbon source uptake rate, thereby restricting growth in a linear manner by restriction of a micronutrient. By this method, productivity was increased to >0.17 g riboflavin/L/h (63). The other method, using Bacillus subtilis AJ 12644 low in guanosine monophosphate hydrolase activity, yielded cmde riboflavin 0.9 g/ L/3 days, when cultured in a medium including soy protein, salts, and amino acids (64). 

A fermentation such as that of Pseudomonas dentrificans typicaby requires 3—6 days. A submerged culture is employed with glucose, comsteep Hquor and/or yeast extract, and a cobalt source (nitrate or chloride). Other minerals may be required for optimal growth. pH control at 6—7 is usuaby required and is achieved by ammonium or calcium salts. Under most conditions, adequate 5,6-dimethylben2imida2ole is produced in the fermentation. However, in some circumstances, supplementation maybe required. 

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