Rabbi Zushe Blech, Kehilas Bais Ben Tziyon, Monsey, NY
Centuries ago, the ancient Greeks recognized that there were certain properties in leaven which caused chemical changes in flour and water converting it into bread. They called the magical ingredient "enzyme" which is the Greek term for "in leaven." Today enzyme remains the term by which we refer to these biological catalysts. We now understand that enzymes are proteins found in every living organism be it animal, vegetable, or microbial.
How does an enzyme work? Let us examine how enzymes function using a kernel of barley as an example. Barley is composed of endosperm, germ, and a layer of bran. The living part of the seed is the germ which lies dormant until it is planted. When the germ comes into contact with water it germinates and begins growing. The living germ needs nourishment which is provided by the starch in the endosperm. However, the germ is not able to digest the starch in its natural state. The germ secretes an amylase enzyme that breaks the starch into smaller units of glucose and maltose which it can then digest. By assisting in this vital chemical reaction, the enzyme played a key role in the life of the organism.
Furthermore, it was realized that if one soaked barley in water and allowed it to germinate, a sweet syrup could be extracted from the barley, even though barley is not sweet at all ! This enzyme conversion, where malted barley produces malt syrup, is known as malting. It was also noted that the malted barley could be used as an aid in the fermentation of the other grains. Food technology now understands that it is the enzyme in the malted barley that acts as the catalyst that breaks down the starch into the sugars, glucose and maltose.
Almost all enzymes used in food preparation "degrade the substrate", i.e. break the food into smaller units as shown in our barley example. Sometimes an enzyme is used to change one molecule into another molecular configuration. For example, the glucose enzyme, glucose isomerase, changes glucose into fructose.
Enzymes used in the food industry are derived from the following sources: Animal enzymes - Rennet, an extract of thefourth stomach of a calf, is rich in the enzymes rennin and pepsin. Both of these enzymes cause milk to curdle into cheese.
Another well known animal enzyme is lipase which is extracted from the glands of animal tongues, or from the gullet of lambs, calves, and kids. This enzyme creates unique flavor sensations in butter fat and is used in numerous products such as margarine, vegetable oil, butter flavor microwave popcorn, chocolate, caramel, and natural and/or imitation dairy products. Pancreatin and trypsin are enzymes derived from an animal's pancreas which are used in baby formulas.
Vegetable Enzymes - some examples of major plant derived enzymes are papain from the papaya plant, bromlain from pineapple, ficin from figs, and amylase from barley. Popular applications of vegetable enzymes range from meat tenderizers to corn syrup.
Microbial Enzymes - Bacteria, fungi and yeast are the microorganisms that produce enzymes as part of their natural metabolism. Modern technology has been able to manipulate the growth of these microorganisms to produce an abundance of desired enzymes. These enzymes can be harvested and concentrated for use in other applications. Over the years as microorganisms were isolated and grown, natural mutations were being observed. Some mutations produced superior enzymes and were then isolated and propagated. Other mutations were induced by manipulating the growth environment of the microorganism.
Genetically Engineered Enzymes - A more recent advance has been the development of genetic engineering, commonly known as cloning. Scientists have now learned to reprogram microorganisms found in nature with genetic information copied from a different organism! This allows the "programmed microorganism" to produce new enzymes which they had not normally produced.
A good example of a genetically engineered enzyme is commonly referred to as microbial rennet. As mentioned earlier, rennin the primary enzyme found in rennet is the enzyme used to break the casein molecule in milk causing it to curdle and make cheese. Due to the limited amounts of animal renin available, scientists were able to grow microorganisms under appropriate conditions and produced microbial rennet which we use to make Kosher cheese.
A technical problem with microbial rennets was that theywere not chemically identical to natural rennet and could causeundesirable flavor characteristics in cheese production. Today,several companies have come up with genetically altered micro organisms that have been coded to produce true renin.
Halachic concerns - What are the Kashrus concerns in enzyme production? Animal enzymes are generally considered non-Kosher. Plant enzymes, extracts of plant tissue, usually pose no Kashrus concerns. Microbial enzymes, are derived through microbial fermentation pose an entire series of halachic issues and concerns. Microorganisms, i.e. a fungi, bacteria or yeast, are living entities and must be preserved to keep them alive so they can grow, propagate and produce the enzymes in sufficient quantities to be used in large scale applications. Once the enzymes are separated from the organism, they too need to be diluted and standardized.
We see that enzymes must be carefully monitored from their early growth through final standardization because of Kashrus concerns. The key considerations of the status of microbial enzymes is the Kashrus of the media on which these microorganisms are grown and the nutrients that feed the microorganism. These must be Kosher because the microorganism assumes the Halachic status of the media and from the nutrients that feed the microorganism. Once the enzyme is produced, the next Kashrus concern are the chemicals used to preserve or standardize the enzyme, such as glycerin; they too must be Kosher.
Enzymes that are produced through genetic engineering have similar Kashrus concerns as their conventional microbial counterparts.
Regarding Kosher for Passover Enzymes - extra care has to be exercised to make sure that any yeast extract, glucose, or dextrose must be checked to ensure that it is not made from Chometz starch.
We read about a brave new world emerging in food science with the potential of major change in food processing and production. These changes will affect the Kashrus which we are working to protect. By being aware of these issues we can take the steps necessary to deal with these issues al pi torah(according to torah).
The Star-K would like to thank Rabbi Blech and Rabbi Yosef Grossman, editor of the OU Daf Hakashrus for their permission to use the enzyme series in preparation of this article.