Potato starch acidic hydrolysis

Several carbohydrates such as corn and potato starch, molasses and whey can be used to produce lactic acid. Starch must fust be hydrolysed to glucose by enzymatic hydrolysis then fermentation is performed in the second stage. The choice of carbohydrate material depends upon its availability, and pretreatment is required before fermentation. We shall describe the bioprocess for the production of lactic acid from whey. 

Tabata, S., Hizukuri, S. (1971). Studies on starch phosphate. Part 2. Isolation of glucose 3-phosphate and maltose phosphate by acid hydrolysis of potato starch. Starke, 23,267-272. 

Glucose syrups, also known as com syrups in the United States, are defined by the European Commission (EC) as a refined, concentrated aqueous solution of D(+)-glucose, maltose and other polymers of D-glucose obtained by the controlled partial hydrolysis of starch (Howling, 1984). Glucose syrups were fust manufactured industrially in the nineteenth century by acid hydrolysis of starch. Hydrochloric acid was normally used, because sulphuric acid caused haze in syrups due to insoluble sulphates. The source of starch can vary in the United States corn is widely used, whereas in other parts of the world wheat, potato and cassava starch are also employed. Acid hydrolysis of starch is still used today. The method is non-specific, but if conditions are tightly controlled, it is possible to make products with a reasonably consistent carbohydrate profile. 

Amylopectin of potato starch and probably amylopectin of other tuber starches occurs as a natural ester of phosphoric acid. Potato amylopectin" contains approximately 0.07-0.09% phosphorus, " or one phosphate group for every 212 to 273 anhydroglucose units. The phosphate appears to be attached mainly to the primary alcohol group since, on hydrolysis, potato amylopectin (separated by electrodialysis)... 

Dextrin is prepared by the incomplete hydrolysis of starch by heating in the dry state with or without the aid of suitable acids and buffers moisture may be added during heating. The PhEur 2005 specifies that dextrin is derived from maize (com) or potato starch. A specification for cassava is included in the USPNF 23. 

Preparation. D-Glucose (often called dextrose commercially, because of its dextrorotation) is manufactured on a large scale by acid hydrolysis of starch, usually potato starch in Europe and com starch in the United States.96... 

B. cereus var. Mycoides could produce two kinds of starch enzymes /3-amylase and pullulanase, where the optimum condition pH is 6-6.5, temperature is 50°C, and the maximum conversion rate (maltose from starch by hydrolysis) is about 95% [18]. In the 1980s, Novo Nordisk Denmark had received Acidophilic Bacillus that hydrolyzed puUulan the pullulanase from it is now the most widely used, and has the largest output [18]. In 1986, Yoshiyuki Takasaki isolated B. subtilis producing heat and acid stable pullulanase, which could produce the mixture of pullulanase and amylase, of which the optimum pH of pullulanase was 7.0-7.5, but also maintained 50% of enzyme activity at pH 5.0 [19]. In 1987, E. Madi and G. Antranikian reported a simultaneous production of u-amylase, pullulanase and glucoamylase bacteria Clostridium thermosulfurgenes. In addition, some actinomycetes such as Streptomyces diastatochromogenes, Beauveria actinomycetes and Micromonosporaceae, Actinomycetes thermomonosporaceae also produce pullulanase. In plants, such as rice, beans, potatoes, sweet corn and malt, pullulanase was observed [20]. 

Use d-G. is produced by acidic hydrolysis of potato or corn starch and is marketed in the pure crystalline form as dextrose as well as in 5-50% solutions as G. preparations for parenteral nutrition in hospitals. G. is also used in chemical synthesis and for technical purposes. A considerable amount is used in the form of G. syrup for the manufacture of confectionery products, for the latter purpose increasing amounts of so-called isosyrup (G. syrup partially isomerized enzymatically to fructose) are now being used. 

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