Sometimes cheesemaking just doesn’t go your way. Curd formation is one of the trickier steps involved in cheesemaking, and in hard cheesemaking it is all the more important. Here are some common problems and solutions that will help you in your quest for beautiful, delicious, perfectly-formed curds.
POOR CURD FORMATION
If curds refuse to form, even after the proper culture, rennet, and set times have been applied, consider these possibilities:
- The milk may be the problem. If the milk was a bit old or store-bought, it may merely be a question of finding fresher or even raw milk for making cheese. Raw, fresh milk always performs better for cheesemaking.
- Make sure the rennet is fresh, has been kept cold, and isn’t past its due date. The fresher the rennet, the better chance of proper curd formation in a timely manner.
Add a few more drops of rennet to a teaspoon of water, then add this extra diluted rennet to the milk, stirring it in sufficiently. If this solution fails, consider your milk source and try again.
CURDS THAT ARE TOO SOFT
If curds form but remain soft and will not firm up, it may be necessary to add more calcium to the milk.
Add calcium chloride next time before heating the milk. The general ratio is ¼ teaspoon calcium chloride diluted in ¼ cup unchlorinated water, per gallon of milk. Increase with each batch until satisfactory curds have been achieved.
It may also help to let the curds set a little longer. If the rennet was a little weak, it may be slower-acting and may require up to ten minutes extra to finish its job.
BUBBLY, SMELLY CURDS
If the cheese is bubbly and off-smelling, there may be contamination problems, possibly coliform contamination. Curds that have been cross-contaminated will be spongy and soft. This is a common problem, so don’t lose heart. Contamination can be due to a number of causes:
- Insufficiently sanitized equipment used for cheese making.
- Contamination may also stem from milk that isn’t fresh enough or that had already begun to acidify before cheese making.
- Weather can cause contamination issues during cheese making, as well. Excess heat and/or humidity may hinder your cheese making efforts.
- See Sanitization During Cheesemaking and Cross Contamination
- Remember to keep your milk covered when it is setting for any amount of time. Allowing it to be open to the air will invite bacteria to invade the developing milk.
All of these issues are easily solved, so don’t despair. Keeping your ingredients fresh and cold prior to making cheese is the best and most effective step you can take towards ensuring good curd formation. Keeping cheesemaking equipment clean and dedicating it only to making cheese will help, as well. If it does become necessary to toss a half-done batch of cheese, write down the steps taken and possible causes and results in your cheesemaking notebook. That way you know what to amend next time.