Chemistry Reference
In-Depth Information
process. Employing protease enzymes, one can easily perform physical processes such as
high temperature resistance for laundry cleaning.
With advances in biotechnology, the horizon of enzyme applications is getting broader day
by day. Enzymes are now being used in newer processes that could compete with synthetic
processes which were previously not commercially viable. For example, several companies
are nowadays developing newer enzymes that could convert cellulosic biomass into ethanol
to be blended in fuels. Other examples include the use of enzyme technology when making
sugars from starch, which helped turn high fructose corn syrup production into a multi-billion
dollar industry.
Most industrial enzymes are produced by modified microorganisms (by recombinant DNA
techniques) for the following reasons:
1.
Higher expression levels.
2.
Higher purity (% enzyme protein vs. % other components).
3.
Cheaper production due to the above.
4.
Recombinant DNA techniques open the door to engineering the enzyme protein.
5.
Enzymes can be expressed which originate from organisms which have low expression
levels or which are pathogenic.
Protein engineering (item 4 in the list above) can improve enzymes with regard to, for
example, oxidation resistance, improved processing tolerance, changed substrate specificity,
improved thermostability and improved storage stability, for example, in detergent systems
containing bleach agents.
Recombinant DNA techniques may open the door to the application of enzymes from
so-called extremophiles. These are microorganisms which can, in contrast to mesophiles,
grow under extreme conditions. Such organisms grow under the following conditions:
90
◦
C stability)
Psycrophiles (extreme low temperatures, 0
◦
Corlower)
Thermoacidophiles (high temperature, low pH)
Barophiles (high pressure)
Halophiles (high concentrations of salt)
Alkaliphiles (high pH)
Acidophiles (low pH)
>
Thermophiles (high temperature
It can be imagined that such organisms either produce a different range of enzymes than
mesophiles, or produce enzymes with extreme characteristics, such as temperature or stability
and activity at extreme pH values.
1.7
FOOD ENZYMES
1.7.1 Food biotechnology
The food industry is using a wide variety of crop plants and animal products as basis
for their manufacturing processes, leading to an even wider variety of consumer products.
Biotechnology, which has been used to manufacture food products for more than 8000 years,
offers ways to improve the processing of raw materials into final products. Bread, alcoholic
beverages, vinegar, cheese and yogurt and many other foods have been made using enzymes
