Com syrup, high fructose

Higher profits are the major incentive for unlawful adulteration. The traditional adulterants are inverted sugar syrup, conventional com syrup, and high-fructose com syrup. Dehydration of fructose can produce hydroxymethylfurfural (HMF). HMF is usually indicative of adulteration with inverted sugar syrup. However, it is somewhat ambiguous because HMF can legally be present in honey that has been subjected to heat or abusive storage. 

The major current industrial use for saccharidases is in the manufacture of high fructose com syrup from starch. The current process requires thermostable enzymes and three processing steps because the enzymes used are not compatible at the same pH and temperature (see Figure 1). Industry is looking to improve the process by developing 1) an improved a-amylase that works at low pH that has a low Ca" ... 

Sucrose occupies a unique position in the sweetener market (Table 3). The total market share of sucrose as a sweetener is 85%, compared to other sweeteners such as high fructose com syrup (HFCS) at 7%, alditols at 4%, and synthetic sweeteners (aspartame, acesulfame-K, saccharin, and cyclamate) at 4%. The world consumption of sugar has kept pace with the production. The rapid rise in the synthetic sweetener market during 1975—1995 appears to have reached a maximum. 

Enzymes are specific, however. For example, starch is depolymerized using enzymes to D-glucose (dextrose). The solution of glucose is then treated with glucose isomerase [9055-00-9] to give D-fructose in about 42% yield. No D-mannose is formed. Addition of isolated D-fructose to this solution gives the common 55% high fructose com syrup (HFCS) so widely used in soft drinks in the United States. HFCS is about 1.5 times as sweet as sucrose. 

High-fructose com syrups dominate the carbohydrate-sweetened soft drinks sector in some markets - notably in the United States. However, in other markets, for example, Europe, the use of high-fructose glucose syrups (HFGS) is restricted by production quotas, and a variety of carbohydrate products including sucrose, glucose syrups, fructose and fructose syrups are used. 

The development of high fructose com syrup (HFCS) may provide another health benefit attributable to cereal grains (see Syrups). These syrups are being used to an ever-increasing extent by the food industry. Shordy after HFCS came on the market, a dramatic increase in the price of sucrose acted as a spur to the production of the high fructose symps. 

Glucose Isomerization. Enzymatic isomerization of glucose to fructose provides a real alternative to sugar (sucrose) derived from sugarcane or sugarbeets. The commercial product obtained is known as high fructose com syrup (HFCS). Two grades of the syrup have become established on the world market, HFCS-42 and HFCS-55, which contain 42 and 55% fructose on dry substance basis. These products account for over one-third of the caloric sweetener market in the United States. 

The first large-scale commercial application of cross-linked enzyme crystals was the use of glucose isomerase CLCs to produce high-fructose com syrup. While this is not a pharmaceutical or a biotechnological application, it is included here because it serves to demonstrate the economic viability of the technology in a very cost-sensitive business. In this application the CLCs were attached to the surface of a polystyrene-cellulose-titanium oxide composite carrier in a ratio of 9 1 carrier enzyme. The catalyst had a half-life of 150 days at 57°C, and 12-18 tons of dry sugar product could be produced per kilogram of enzyme [37],... 

Of course, carbohydrates are used and manipulated at commercial scales. The isolation of sucrose and the enzymatic formation of high fructose com syrup are obvious examples. However, although sucrose is available from a wide variety of sources at very large scale, it has found relatively little application in chemical transformations.1516... 

S)-CPA = (S)-chloropropionic 6-APA = 6-aminopenicillanic acid HFCS = High fructose com syrup. 

Table 35.2 shows the per capita consumption of selected areas.80 Sugar usage patterns, particularly in developed countries, have not changed markedly over the years except in the United States, where high fructose com syrup (HFCS) has replaced sugar in the manufacture of beverages (see Table 35.3). Nonfood uses of sucrose constitute a small portion of total use.81...

The United States is the largest producer of com sweeteners and the largest market for high-fructose com syrup. The major use of HFCS is in beverages and soft drinks, which account for 75-80 percent of usage. Important milestones in the development and growth of HFCS are shown below.87... 

Total Solids Determine the refractive index of a sample at 20° or 45°, and use the tables in High-Fructose Com Syrup Solids, under Total Solids, Appendix X, to obtain the percent Total Solids. 

The isomerization of glucose to fructose opened the way for starch hydrolyzates to replace cane or beet sugar (Dziezak 1987). This process is done with glucose isomerase in immobilized enzyme reactors. The conversion is reversible and the equilibrium is at 50 percent conversion. High-fructose com syrups are produced with 42 or 55 percent fructose. These sweeteners have taken over one-third of the sugar market in the United States (Olsen 1995). 

---