For desserts – yes.
For cheese – no.
There are a lot of cheese making websites where Junket tablets are routinely used in place of rennet. (The best known is probably David P. Fankhauser, PhD’s site.)
This practice is widely applied because Junket tablets are available in most supermarkets and they are slightly less expensive than actual rennet tablets or liquid rennets.
I’ve noticed lately that we (New England Cheesemaking Supply Co.) are often quoted in blogs as being opposed to the use of Junket rennet for making cheese. This is basically true, but there is more to the story than you may know.
When our business was young, there were a few years when we sold almost anything related to cheese, cows and goats, including Junket rennet (1984-5). We even sold the 16 page Junket booklet with old-fashioned dessert recipes.
However, we have always recommended that you use Junket tablets for desserts and not for making cheese. Why? This letter from our September- October, 1981 issue of The Cheese Press (which later became The Cheesemakers’ Journal) pretty much says it all:
We make another case for this on the Mozzarella page of the HELP section of our website:
3. Can I substitute Junket for the rennet tablets?
No. Junket is great for making custard, but it is nowhere near as
strong as our rennet tablets. Cheese rennet is 80% chymosin and 20%
pepsin. Junket is approximately 80% pepsin, so it is much weaker than
cheese rennet. It also contains many additives.
So, there are 2 reasons why we suggest you use real rennet for your cheese and not Junket:
1. Junket tablets contain only a small amount of actual rennet.
2. Junket tablets contain additives – salt, calcium lactate, corn starch, tricalcium phosphate and calcium stearate.
Our question is – If you are going to take the time to make your own cheese, and assuming you are doing it, at least in part to support your healthy lifestyle, why make it with additives?