High-Fructose Corn Syrup production process

High-Fructose Corn Syrup (HFCS) is an extra sweet, inexpensive sweetener used mostly in soft drinks and fruit juices.

Corn is the primary source of high fructose corn syrup in the US. High fructose corn syrup is a liquid alternative sweetener to sucrose that is made from corn, the “king of crops”. It is a caloric sweetener, made from ordinary corn starch, which substitutes for sugar in a wide range of manufactured products.

Corn starch composed of glucose molecules of infinite length, consists of amylose and amylopectin and requires heat, caustic soda and/or hydrochloric acid plus the activity of three different enzymes to break it down into the simple sugars glucose and fructose present in HFCS.

The production of HFCS and corn wet milling are typically an integrated process. The wet milling process separates the corn kernel into its four principal components: the germ, hull, gluten, and starch. High fructose corn syrups, as well as other corn sweeteners, utilize the corn starch slurry produced by the wet milling process as their basic input.

An industrial enzyme, α-amylase produced from Bacillus spp., hydrolyzes corn starch to short chain dextrins and oligosaccharides. Bacterial α-amylases catalyze the hydrolysis of α-1,4 glucosidic linkages and act in a random but reproducible manner to reduce the polysaccharide molecular weight. Enzymatic liquefaction requires precise control of operating conditions like percentage of solids, temperature, time, pH and calcium level to ensure efficient hydrolysis, process economics and easier downstream processing operations.

A second enzyme, glucoamylase (also called amyloglucosidase),produced from fungi such as Apergillus, breaks dextrins and oligosaccharides to the simple sugar glucose.

A glucoamylase dosage is added to produce a maximum dextrose level in 1-4 days. Reaction time is inversely related to dose, so if a given dose yields maximum dextrose in 4 days, doubling or quadrupling the dose will reduce reaction time to 2 days or 1 day, respectively.

The product of these two enzymes is corn syrup also called glucose syrup. The third and relatively expensive enzyme used in the process is glucose isomerase (also called D-glucose ketoisomerase or D-xylose ketolisomerase),that converts glucose to fructose.

Fructose is superior to all nutritive sweeteners and humectants in controlling water in frozen system. Its water activity is low as compared to sucrose, sorbitol, dextrose, mannitol, etc. which makes it a better preservative.

High-Fructose Corn Syrup production process

Technological Development

Technological Development
Technology certainly played a large part in the growth of soft drinks in the second half of the twentieth century.

The development of cans, plastic bottles high speed packaging lines and improvement to distribution systems have been largely responsible for the increase in availability, the decrease in real term cost and the resultant increase in consumption.

The advent of of railways and large steam ships in the 1800s made transportation feasible and indeed drinks were exported from the UK to the USA as early as 1800.

The export trade continued to expand and by the mid-1800s significant trade was being done with far corners of the Empire.

This must have involved considerable cost and on a domestic basic the trade was on a much more local scale.

The industry evolved as a multitude of local businesses operating in a small geographical area, though some larger companies operated several production plants in different parts of the country.

The UK Bottlers; Year Book 1933 listed more than 2000 soft drink manufacturing companies but by 1983 the list had shrink to less than 400, and the number is now down to less than 100.

Likewise the number of bottling plants in the USA grew to reach a peak of 7920 in 1929, remaining fairly constant until around 1950 and then halved to 3727 by 1965 as improved productivity and distribution started to have a significant effect.

This having of the number of bottling plant took place over a period in which per capita consumption rose by over 60%.

The growth of cans and PET bottles at the expense of returnable glass has played a significant part in this continuing productivity improvement, which has been truly amazing.

As recently as 20 years ago a typical returnable glass bottle line producing, 300 bottles/min, required about 25 operating personnel.

Highly automated PET bottle blowing and filling operations have also improved production efficiencies significantly.

Other factors contributing to improved operational/ distribution efficiencies (both in time and cost) include:

• Use of shrink wrap in place of crates or boxes



• Micro-processor controlled equipment, for example, for palletisation



• Automated syrup room operations



• Centralized computer-controlled warehousing systems



• Automated bar-coding and traceability systems
  

Technological Development

Softdrinks Processing: Sterilization of Water

Softdrinks Processing: Sterilization of Water
Free chlorine will be used as the sterilization agent for the water prior to its use in the manufacture of the softdrinks. It is usual to use about 10 ppm of free chlorine for sterilization to ensure that the reaction will reach completion.

Free chlorine may be dosed as chlorine gas but it is usually prepared from sodium hypochlorite solution for safety reasons. In the case where ferrous iron salts are used as the coagulation chemical, free chlorine will be used to oxidize the ferrous salt to ferric salt.

It is usual in this case to dose more than 10 ppm free chlorine into the coagulation tank so the ferrous iron is fully oxidized to the ferric state and so that there is the required excess for sterilization. Where ferric iron is used as the flocculating chemical the residence time in coagulation tank can be included as part of the contact time necessary with free chlorine for sterilization.

In this case the chlorinated water storage tank can be smaller. Free chlorine will not be used as part of the coagulation reactions where aluminum sulphate is used as the flocculating chemical and will generally be dosed after the sand filter, though in some cases chlorine may be dosed into the clarifier to prevent bacterial growth.

Approximately 10 ppm of free chlorine will be dosed into water for sterilization. The reactions that take place will not only destroy bacteria that may be in the water and render it sterile but will also react with other organic molecules that may remain in the water after the clarification reactions.

The residual organics may wary from naturally occurring organic matter to simple organic compounds such as chlorophenols and trihalomethanes that could impart both taste and odor to the final carbonated product. The action of the free chlorine will break down these organic molecules.
Softdrinks Processing: Sterilization of Water