The Flocculation Test or Method

The times given in most cheese recipes are great for beginners and experienced home cheese makers alike. You can check for curd set by the tried and true “Clean Break” method, however there is a better whey to determine curd set for your cheese. A clean break can be tested for quite a while before the edges of the curd start pooling whey and getting jagged cuts. By that time, you’ve likely locked in way more moisture than you want and will end up with bitter cheese.

The flocculation method for better curd is a way to test the point of coagulation after adding the rennet to your milk. Using a factor (determined by the type of cheese you are making, you multiply the time taken for the flocculation point to help you predict the best time for curd set.

1. Add your rennet when the recipe states. Start a timer so you know how many minutes have elapsed.
2. Leave the milk for five minutes, then place a sterilised small plastic bowl or a smooth metal top off a jar upside down on the surface. It should float.
3. Then spin the bowl or jar top gently, whereby it should rotate freely.  Do this every minute or two.
4. You should notice that at around the 8 minute mark you may find slight resistance from the milk, test by spinning every 30 seconds.
5. Between 10 and 15 minutes, the bowl should become ‘stuck’, indicating that the curd mass has formed.  This is the flocculation point.  It may take longer, so don’t panic.  Keep testing till the curds set.
6. Once set, don’t try to spin the bowl any more, just remove it gently and note the time elapsed. At the flocculation point, were you to break into the mass, it will have the consistency of gravy.

Now you have to multiply a factor by the total time it took for the curd mass to set by a figure listed in the table below. (Source: Cheese Forum Wiki)

The factor (normally between 2 and 6) is multiplied by the time it took to reach flocculation point, giving you the time to cut the curd.

So if flocculation time is, for example, 15 minutes, then for Parmesan, total time since adding rennet to when the curd is cut is 37 and a half minutes. This is the optimum time to cut the curd for the type of cheese you are making.

The Cheese Forum states;

“The reason for the different multipliers for different cheese type recipes is because the curd at time of cutting will have different strength, young curd set will more readily release water when cut versus older curd set will release less.”

A soft cheese usually has a higher flocculation time, and a larger curd cut, keeping more moisture in the cheese.

A hard cheese on the other hand has a lower flocculation time, and a smaller curd cut, releasing more whey for a firmer, drier cheese.

Moisture is locked into the curd as the protein bonds become stronger. The longer you allow the milk to coagulate, the more moisture will be trapped in the curd. So if you are trying to make a hard alpine cheese, such as parmesan, you want to work with a very short coagulation time. For a moist, creamy cheese opt for a longer coagulation.