Rennet for Cheese Making FAQ (2024)

FAQs

What happens if you use too much rennet when making cheese? ›

Too much rennet was used or too much butterfat, left your cheese during the process. Rubbery cheese can happen when an excess amount of rennet is used, too much rennet equals a rubber ball, too little, soup!

Too little rennet and you won't form curd. Too much rennet an you'll over-set your cheese, giving it an undesired texture. Too little calcium and the curd won't have the right texture – or even form at all. Too much calcium and the texture, hardness, and melting prosperities, can be wrong.

When adding rennet only 1/4 tsp is added to each gallon of milk, and much of the rennet runs off with the whey during draining. So, the amount of salt left in the cheese is virtually impossible to measure.

Calf rennet contains two enzymes, chymosin and pepsin, in a natural ratio that is suitable for our style of cheese. (Chymosin causes coagulation, pepsin has impacts on the aging process.) This traditional rennet has more reliable results in yield, as well as flavor profile, leading to less defective cheese.

Over time your rennet can begin to lose some of its strength. Just adding a little more rennet can compensate for this. One way to test your rennet to see how active it still is is to take a tablespoon of warm milk (35° C) and add a drop of Calcium Chloride and a drop of rennet. It should set in 5 minutes or less.

Rennet, like other enzymes, has an optimum temperature for its activity. The optimum temperature for rennet activity in milk is around 35 °C to 40 °C [19].

Rennet has a limited shelf life – liquid rennet lasts for 7-8 months when refrigerated and tablets last for up to 5 years when stored in the freezer (2 years at room temp). If you are unsure how old your rennet is or whether or not it is still effective, you can do the following test: Heat one cup of milk to 90F.

Milk that has been heat treated at high temperatures shows longer coagulation times and forms weaker, finer curd which retains more water than normal.

The Milk Does Not Coagulate

The rennet can be either liquid or paste. If the milk does not coagulate, it may be because the rennet you are using is old or unviable. Another reason is the milk is pasteurized to the point that it kills almost everything needed for coagulation to occur.

Coagulate with Rennet

Once your milk and culture have ripened, add about 3/4 tsp of single strength liquid rennet. The milk then needs to sit quiet for 45 minutes while the culture works and the rennet coagulates the curd.

Are calves killed for rennet? ›

Most stomach-derived rennet is taken from the fourth stomach of young, unweaned calves. These animals are not killed expressly for their rennet; rather they are killed for meat production (in this case, veal) and the rennet is a byproduct.

The liquid versions of rennet are much easier to measure in smaller quantities than the tablets, and powders are so concentrated they're best for really big batches, so for those making 1-2 gallon batches (or smaller), liquid rennet will likely be a better choice.

Pig pepsin and chicken pepsin were used previously, however, not now. All successful rennet substitutes are aspartyl proteinases. Proteinases from Rhizomucor miehei, R. pusillus, Cryphonectria parasitica, Aspergillus oryzae and Irpex lactis are used for commercial cheese production.

NOTE: Classic cheesemaking uses ingredients like citric acid and rennet. But white distilled vinegar works too! It turns out a little different but still amazing. If you would like to go the more classic route you can pick up a cheesemaking kit that has everything you need minus the dairy of course.

Just about any cheese can be improved upon with the use of rennet, but it's not always a definite necessity. Cheeses that exclude rennet will then use another method of coagulation, such as the addition of an acid (like vinegar) or a culture. Some cheeses that don't always require the use of rennet include: Mozzarella.

Heating of milk: Excessive heating of milk precipitates the soluble calcium and reduces the setting ability of the milk. For home pasteurisation it is important not to over pasteurise the milk. Milks available commercially are usually pastuerised for general use and not specifically for cheesemaking.

CURDS ARE TOO SOFT

If it does not improve, this problem may come from ultra-pasteurization or ultra-hom*ogenization of the milk. You can try adding more rennet, depending on where you are in the cheesemaking process. You should add more rennet only to milk that has not yet been cut into curds.

Why won't my cheese melt? There are many reasons, but the biggest is the moisture content. The moisture content of the cheese has a great effect on the melting process. Cheese that contains higher amounts of fat will melt better than one that doesn't.

The type and amount of rennet used in cheese production can significantly affect the final product's flavour, texture, and consistency. Using too much or too little rennet can result in cheese that is too soft, too hard, or has an unpleasant flavour.