Glycolic acid Fermentation Process

Fermentol (also Pratol Glycerine or Pro-toglycerine), A glycerine produced in Germany from sugar by a fermentation process. Trimethylene glycol in the product evolves more heat than glycerine on nitration, is more soluble in the mixed acid, and thus contributes to fume-offs Refs 1) Naoura, NG(1928), pp 31, 229 2) Marshall 3(1932), p 42... 

Since proteins strongly adsorb at interfaces, very low concentrations (as low as 1 mg/L) can influence foaming. This can cause foaming where it is not desired, such as where it causes operational problems in fermentation processes [844]. Additives with fatty-acid chains generally tend to be capable of stabilizing foams, whereas those with unsaturated fatty-acid chains generally tend to destabilize foams [820]. Other food defoamers that have been used include oils, glycols and siloxanes [486,844]. Some commercial food defoamers are listed in Ref. [845],... 

Glycolic acid can be produced via fermentation process [6] from glycolo-nitrile hydrolysis by mineral acid, such as sulfuric acid [7,8]. Both processes produce a multi-component solution with the acid concentration typically less than 10 wt% for fermentation technology, and less than 40 wt% for glycolo-nitrile hydrolysate. The acid can be produced by the enzymatic conversion (typically the enzyme catalyst used is nitrilase or a combination of a nitrile hydratase and an amidase) of glycolonitrile which results in the production of an aqueous solution of ammonium glycolate [9]. 

Losses are a natural part of any processing plant. The control and reduction of the losses will, in part, determine the economic effectiveness of the plant s operation. All areas of the glycerine recovery plant can produce losses. In storage, fermentation can cause serious losses of glycerine due to the formation of trimethylene glycol, gases, and acids during decomposition. 

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