The conversion process that makes basic commodities into value added products usually involves fermentation by microorganisms, and use of biocatalysts like amylase hydrolases, say the review authors from the University of Georgia in the US and National Taiwan Normal University.
But they note that recombinant enzyme technology, protein engineering, and enzyme immobilization are “powerful tools” that can enhance the activity of enzymes – as well as lower costs, increase thermostability, improve pH stability, and enhance productivity.
This makes the technology competitive with chemical processes for starch hydrolysis and conversions.
Value-added industrial products that that can be made in this way include biofuels, as well as food ingredients such as sweeteners (hugh fructose and high maltose syrups, glucose, trahalose), and also wine.
“The greatest advantages of using enzymes for food processing and for industrial production of bio-based products are their environmental friendliness and consumer acceptance as being a natural process,” they wrote in an article to be published in the Journal of Agriculture and Food Chemistry.
They also draw attention to the potential benefits for farmers, saying that, as well as aiding the industrial sector, it could improve their commercial incomes.
Rice is taken as a case study, and the use of individual enzymes and recombinant enzyme technology to carry out liquefaction – to convert granular starch into soluble dextrins of lower molecular weight – is compared with the use of amylases as catalysts.
The enzyme processes are seen to be “preferred and more desirable”, bringing savings in terms of energy, yield and productivity.
Nor do the researchers see enzymatic processes as the end-game. They say that new biotechnology, including gene cloning and expression and transgenic plant technology, are expected to “further develop a more simple, efficient and inexpensive approach to the application of enzymes for producing high-value-added products or agricultural produce with an easily accessible and important nutrient source”.
Journal of Agriculture and Food Chemistry (ASAP web release)
“Biocatalysis for the production of industrial products and functional foods from rice and other agricultural products”
Authors: Casimir Akoh, Shu-Wei Chang, Guan-Chuin Lee, Jei-Fu Shaw