Ninety percent of cheeses contain vegetarian enzymes, as of 2010, according to the Central Co-op's Madison Market. Through technology it has become the least expensive option; and therefore, it is the most attractive option for cheese manufacturers. Traditionally, cheese enzymes or rennet were derived from the stomach lining of young cows. It was a labor intensive process and contained animal-based ingredients, which excluded vegetarians. Check the ingredient label for "vegetable enzyme or rennet" or "microbial enzyme" to ensure you are selecting the vegetarian option.
Vegetable enzyme or rennet does not contain animal products; therefore, is considered a vegetarian cheese enzyme. It is solely derived from vegetables. Certain cultures have used fig tree bark, nettles, cardoon thistles, mallow and ground ivy or creeping Charlie. Enzymes made with thistle are typically used in the Mediterranean to make some cheeses, such as feta, mozzarella and ricotta. The thistle plant is a spiky plant that has a purple or white flowers. As of 2010, there is no vegetable enzymes made as an large-scale industry.
A vegetarian cheese that is derived from microorganisms is called microbial rennet or enzyme. It is made from molds, such as rhyzomucor miehei. This fungus is found in many locations outdoors. The molds are made in controlled conditions in a fermenter and purified, and concentrated so that it does not become unhealthy for human consumption. Microbial enzymes may increase the bitterness of cheeses, especially in mature cheeses, and is a major reason that some high-yielding cheese manufacturers choose a genetically modified enzyme.
Genetically Modified Enzyme
Genetically modified enzymes are primarily microbial in its base. Types of microorganisms used are bacteria, funji or yeasts. Even though it can be considered vegetarian, it does feed microorganisms cow genes that produce the enzyme, chymosin. Any potentially harmful genes, such as ones for antibiotic resistance, are filtered out of the enzyme before it is processed, as reported by the U.S. Department of State. The Vegetarian Society recognizes genetically modified microorganisms as a vegetarian-friendly enzyme. Genetically modified enzymes not only have a less bitter taste than microbial enzymes, they are less expensive to produce.
Vinegar Or Citric Acid
Lemon juice or vinegar are used to congeal cheese. It is usually used in ricotta and for a heat-precipitated curd. This type of enzyme is rarely used, because of its sour taste.