For those of use who have a love of cheese making and a concern for Kashrut (keeping kosher), cheese making presents some unique challenges. Â Rennet which is used to separate milk solids, lipase which adds flavoring to (mostly) Italian hard cheeses, and basic cultures which gives cheese its unique flavor all have a variety of Kashrut issues.
The first issue is rennet; rennet is the key ingredient which allows milk to separate into solid and whey. Â Rennet as a chemical is harvested from the stomachs of animals and is therefore not kosher. Â Three forms of rennet that are not produced from animal sources have been created over time, they are:
- Vegetarian Rennet – or vegetable rennet, sources include nettles, thistles, mallow, ground ivy, and unfermented soybeans. Â Vegetable rennet has a poor reputation as having a ‘off’ taste as the cheese matures or ages. Â Gianaclis Caldwell (Pholia Farm) who taught us that vegetarian rennet is great if used in MODERATION and that most new cheese makersÂ Â over rennet their cheese.
- Microbial Rennet – Produced from some molds such as Rhizomucor miehei are able to produce proteolytic enzymes (the active ingredient in animal rennet), these are both vegetarian and kosher. Â These rennets also have a reputation for adding bitterness to the cheese after long periods of maturation (the worst kind of rennet behavior :-))
- Genetically Engineered Rennet – Starting in the early 1990’s, engineers created a genetically engineered form of rennet. Â These have become so popular that by 2008 over 80% of all cheese made in the US used this type of rennet. Â These are often a combination of genetically engineered chymosin and natural pepsin to create this rennet. Â Until recently, this rennet was unavailable in small quantities, now it’s both available and has an OU heksher. Â The Cheesemaker has hobby quantities available for purchase.
Lipase powder is generally used in the production of all (or most) of the italian cheese (Feta, Romano, Parmesan, Mozzarella etc.) Â Lipase is also an animal byproduct and therefore is not kosher. Â A recent Genetically engineered version has become available including one that is kosher. Â When I inquired last year, the minimum shipment size was a container truck. 🙂 Â What I’ve concluded is the quality of milk is more important than the addition of Lipase; I’ve made lots of successful feta, mozzarella and even a parmesan without lipase. Â Maybe in a few years we can get kosher hobby sizes.
Cheese cultures are bacteria specimens that are needed along with time to ripen which produce a cheese’s taste and texture. Â Cheese cultures are not from animal sources and you can get hekshered cultures from the cheesemaker.