Technical Talk: December 2014

Enzymes have been widely accepted in the baking industry as very valuable tools.  

Enzymes have been widely accepted in the baking industry as very valuable tools.  

Enzymes play a very important role in our lives. They are present in all biological systems, where they function as mediators for many natural biochemical reactions.  They are mainly proteins and are named after the substrate they act on. For example, amylases break down or modify starch, proteases affect proteins, and lipases act on lipids and fats.

Enzymes are widely used in the food industry and have been in many processes for thousands of years. Fermentation processes such as wine, beer and bread-making, which use yeast and bacteria, rely on the enzymes produced by these micro-organisms. As the role of the enzymes in these processes was revealed over time, they began to be used in various industries to speed up processing reactions.

RUDE ENZYMES
In the baking industry, rude enzymes were initially used in the form of malt barley flour (MBF) and others. MBF is produced from germinating barley seed; although it is mainly an amylase, it is not pure and contains other side activities. As the commercial availability of many other purified forms of enzymes increased, they became important tools for baking processes.

Enzymes are used to improve wheat flour performance, reduce the effect of staling and replace or reduce other unfriendly chemicals used in baking. Amylases reduce the complex starch molecule in flour to smaller groups of glucose units that can be absorbed by the yeast and provide food for the fermentation process. In addition, specialized amylases modify the starch in order to slow down the staling of bread and other baked goods.

AMYLASES
There are two major types of amylases: alpha amylases, which break down damaged starch to produce dextrins (short chains of sugar molecules), and beta amylases, which break down the dextrins to form maltose molecules (two glucose units).

In baking, amylases from three major sources are generally used: cereal (which are inherent in wheat and other grains) and fungal or bacterial amylases (produced by various fungi and bacteria). These three types of amylases have different activities and tolerances to temperature and pH, so it is important to be careful when selecting which type to use. For example, if high amounts of bacterial amylases are used in bread, their activity will continue beyond the baking process and the crumb will become sticky and difficult to slice.

LIPASES 
Lipases, which are enzymes that either break down or modify fats and lipids, are found in nature and in many cases are responsible for the fat’s oxidation and the onset of rancidity in food products. The lipases found in the kernel are normally dormant until the wheat is milled. In the process of milling, when the germ (containing high amounts of lipids) is separated, lipases become active and as a result will very quickly oxidize the lipids in the germ and produce unpleasant, rancid flavours. For this reason, freshly milled germ has to be consumed within a few days of milling or used as animal feed. The shelf life of the germ can be extended if the fat is removed by chemical solvents and other methods or by careful temperature inactivation exposure of the lipases.

Lipases are also used in the industrial processes to modify fats for the production of ingredients. They are used in the production of shortenings from oil without the harmful effect of the partial hydrogenation, which results in the formation of the undesirable production of high amounts of trans fats.  

There are many advantages in using enzymes in baked goods. They are often more economical because they are used in minute quantities; they are very easy to use, as most are available in powder form; and they are very precise in controlling reactions. They can contribute to longer shelf life of the product, improve control of grain, reduce mixing time, improve dough tolerance and increase the performance of poor-quality flour.

As with any other ingredient, there are some disadvantages. There is a small risk of overdosing, and handling may induce allergies. In addition, because of the time-dependent reactions, more attention is required. However, the pros far outweigh the cons, and enzymes have been widely accepted by the baking industry as valuable tools.  

For more information, or fee-for-service help with food technical and processing issues and needs, please contact Dr. John Michaelides at John Michaelides Consulting. He can be reached at 519-743-8956, at Bioenterprise at 519-821-2960 or by email at j.jmichaelides@gmail.com. Bioenterprise is a company of experienced professionals that coach and mentor emerging agri-technology companies from planning to start-up to profitability and beyond.