Syrup acid-enzyme hydrolysis

Acid-Enzyme Hydrolysis. Starch first is liquefied and hydrolyzed to specific dextrose equivalents with hydrochloric acid. After evaporation to 60 percent solids, a saccharifying enzyme (fungal amylases) is added to continue hydrolysis to the desired level. By choosing two or more types of enzymes (such as alpha-amylases, beta-amylases, or gluco-amylases) and adjusting the initial acid hydrolysis, syrups with different ratios of dextrose, maltose, and higher saccharides can be obtained." ... 

Invert sugar. Invert sugar, sometimes referred to as partially inverted refiner s syrup, is produced by acid or enzymic hydrolysis of the disaccharide sucrose into its 2004 component pails of fructose and dextrose (glucose). Invert syrups usually contain a mixture of sucrose, fructose and dextrose. The main advantage of such a syrup is the reduced likelihood of crystallisation and an increase in osmolality, which may be useful in reducing spoilage risk. 

Glucose syrups. Glucose syrups are a group of industrial syrups manufactured from starch - usually corn starch (maize). The starch may be hydrolysed by either acid or enzymic hydrolysis or, more usually, a combination... 

Both pilot-plant and plant-scale processes for cellulose hydrolysis or digestion by acids, enzymes, and microorganisms have been built (I, 7,15,27). Acid and enzyme processes usually have as their objective the production of a sugar syrup, while the microbial process usually results in microbial protein for animal feed. Figure 10 is illustrative of a microbial process (29) that has been developed to convert the unused cellulosic material in manure to recycle feed. Similar processes have been developed... 

Glucose/com syrups may be manufactured by either an acid or an acid-enzyme process. Acid-catalyzed hydrolysis was the traditional method of corn syrup production and is still the most common method for producing sweeteners up to about 42 DE. Since acid-catalyzed hydrolysis of sweeteners to 55 DE or above creates products of reversion, such as gentiobiose, isomaltose and trehalose, which give unacceptable flavors to the syrup, these syrups are usually made by acid-enzyme processes.18... 

Commercial dextrins are specifically the oligomers of starch. White dextrins, so called because of their visual appearance, are produced from a 30-40% suspension under the mildest possible hydrolysis conditions (79-120°C for 3-8 h in 0.2-2% H2S04 or HC1). Yellow dextrins and British gums are the partial hydrolysates at higher time-temperature integrals. Maltodextrins, dextrose equivalent20 5-19, derive from controlled enzyme or acid partial hydrolysis of gelatinized corn starch. The 20-24 dextrose equivalent hydrolysates tire com syrups (Appi, 1991). 

The com industry makes widespread use of enzymes for carbohydrate conversion. The advent of enzyme technology in the corn industry in the 1960s dramatically changed the starch industry and allowed the development of new products. Today, enzyme hydrolysis of starch has largely replaced acid hydrolysis, which is used as an adjunct in starch conversion. Enzymes used to make corn syrups and HFCS include the following. 

Starch conversion refers to the process of converting starch into other products. It involves gelatinization, liquefaction, and saccharification. Liquefaction refers to the acid-or enzyme-catalyzed conversion of starch into maltodextrin. Starch, usually from wet milling of com, is pumped in a slurry to the conversion plant, where it undergoes one or more hydrolytic processes to yield mixtures of various carbohydrates in the form of syrups. The kind and amount of the various carbohydrates obtained depend upon the type of hydrolysis system used (acid, acid-enzyme, or enzyme-enzyme), the extent to which the hydrolytic reaction is allowed to proceed, and the type of enzyme(s) used. The fact that most starches consist of two different kinds of polymers... 

Maltodextrins and corn syrup solids are produced from starch, usually corn. The starch, which is almost pure carbohydrate, is cooked or pasted to open the granule and then hydrolyzed. Products can be made by hydrolyzing with acid or enzymes or with a combination of acid and enzymes. After the desired amount of hydrolysis has occurred, the reaction is stopped, and the product is filtered to remove insoluble materials and then dried. 

Oligo- and higher saccharides are produced extensively by acid-and/or enzyme-catalyzed hydrolysis of starch, generally in the form of syrups of mixtures (12). These products are classified by their dextrose equivalency (DE), which is an indication of their molecular size and is a measure of their reducing power with the DE value of anhydrous D-glucose defined as 100. 

More than half of the total production of starch is converted into syrup dextrins or dextrose by acid hydrolysis and/or enzyme action or heat treatment. 

The sucrose industry is a comparatively minor user of enzymes but provides few historically significant and instructive examples of enzyme technology. The hydrolysis inversion of sucrose, completely or partially, to glucose and fructose provides sweet syrups that are more stable (i.e., less likely to crystallize) than pure sucrose syrups." The most familiar golden syrup produced by acid hydrolysis of one of the less pure streams from the cane sugar refinery but other types of syrup are produced using yeast (Saccharomyces cerevisiae) invertase. 

The biocatalytic conversion of starch to fructose syrup is a well-established process and provides a good example of a biotechnological application. In this bioprocess the consecutive use of several enzymes is necessary, which is not desirable in a biotechnological application. The first step in the process is the conversion of starch to oligomaltodextrins by the action of a-amylase.The concomitant injection of steam leads to extreme demands on the thermostability of the enzyme. Using traditional a-amylases, the pH has to be adjusted to an undesirably high level and calcium must be added to stabilize the enzyme in the system. New a-amylases with optimized properties, such as enhanced thermal stability, acid tolerance and ability to function without the addition of calcium, have recently been developed and successfully applied in the hydrolysis of starch. i° Engineering approaches have also been undertaken to develop the hydrolysis process. ... 

Sweeteners used throughout the world are usually derived from starch. Frequently, these are produced by an acid hydrolysis process into simpler carbohydrates. Nowadays, acid hydrolysis has been replaced by enzymes. In the enzymatic process, the treatment of starch results in various syrups that are used in the food, beverage, and pharmaceutical industries. 

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