Thistle Versus Calf Rennet

[GlabrousD]

Hiya All,

I've been using BioRen Calf Rennet tablets to date in my makes with great success. However I now want to try a Camel milk cheese and have read that "normal" rennet doesn't work. So I've bought a bottle of Thistle rennet from ArtisanGeek and was wondering if someone could provide me with an equivalent measure compared to the tablets. I currently use 1/2 tablet for two gallons of milk... how much thistle rennet should I use to equate to this?

I realise that the Camel milk will react very differently to the regular (pasteurised & homogenised) cow's milk but I'd appreciate a starting point for my experiments.

Thanks in advance for your help. Cheers, GD.

[jwalker]

The bottles I have seen usually have the ammounts on the label , at least for cows , goat or sheeps milk , Camel milk is totally different from what I hear.

I can't help you much here , but I am very interested to hear the results of this make.

I did find an article on Camels milk cheese making , after you piqued my interest , it was kind of interesting.

It's here   http://www.fao.org/docrep/003/t0755e/t0755e02.htm#j      and good luck. :D

[GlabrousD]

Do you know jwalker I must be particularly hard-of-thinking today. I've just checked the bottle and - lo and behold it says "Dilute 1/8 teaspoon rennet in 1/4 cup... water for each 1 gallon milk".

My apologies All; thanks very much for the suggestion jwalker and for the link... it's one I've read and about the only information available. Who knows I could fill the niche and become the World Expert on artisan camel cheese... yeah, unlikely :)

I'll report back on the camel milk cheese in whichever forum is appropriate... I might try Caerphilly first as it's a fairly rapid make and I'm too impatient to wait for a cheddar :)

Cheers, GD.

[jwalker]

I read one article that stated you needed 50 to 100 times the rennet to coagulate Camels milk as opposed to cows milk , and even then it could take four times longer to set.

That's a LOT of rennet !  :o

[Sailor Con Queso]

Thistle rennet is extremely weak compared to conventional rennet, so I wouldn't change milk type and rennet at the same time. If something goes wrong, you have no way to identify the problem. I would first use your normal rennet with the camels milk and see what happens. Then if it coagulates properly, I would test the thistle rennet on a VERY small amount of the camels milk.

[linuxboy]

IMO preacidify the milk a bit and use pepsin instead of cardosin. It'll set and you'll have fewer bitterness issues.

[GlabrousD]

Dear Sailor & Linuxboy thanks very much for the advice and excuse me for not replying sooner. I'm currently knee-deep in a Google search for white papers on Pepsin, Cardosin, Chymosin et al.

Once I understand the basic functions and actions of each I'll be back to pester you if you don't mind? :)

I'd rather not ask questions from a position of ignorance as it only wastes other people's time explaining things I could discover on-line with a bit of effort.

Thanks again. Cheers, GD.

[GlabrousD]

So to summarise my findings:

Cardosin A - extracted from dried flowers of Cynara cardunculus
Cardosin B - extracted from dried flowers of Cynara cardunculus
Chymosin - extracted from the abomasa (fourth stomach) of sucking-calves (calf rennet)
Pepsin - extracted from the abomasa (fourth stomach) of sucking-calves (calf rennet)

Apparently most commercial rennet is about 95% Chymosin and 5% Pepsin. Junket rennet however is 80% Pepsin.

There's a fascinating white paper here: http://repositorio.ucp.pt/bitstream/10400.14/3582/3/Comparative%20studies%20on%20the%20gelling%20properties%20of%20cardosins%20extracted.pdf
Which indicates that the dried flower's Cardosin A & B give clotting strengths of 1160 and 7556 IMCU/g whilst the Chymosin gives 174,000 IMCU/g. Thus the Thistle rennet is orders of magnitude weaker as mentioned by Sailor.

Lower pH (6.2 to 6.4 - by adding CaCl) gave better results than higher (6.6pH) but the performance of Chymosin suffered more than that of the Cardosins. Hence Linuxboy's suggestion of a lower pH?

So to follow Linuxboy's advice is it sufficient for me to lower the pH with CaCl or should I use citric acid or similar? Also should I buy Junket rennet for the Pepsin or is there a better alternative please?

Thanks in advance for the help and advice. Cheers, GD.

[Sailor Con Queso]

You should let the starter bacteria do their job and produce enough acid to drop the pH.

[GlabrousD]

Thanks very much Sailor - I'll give it a shot and will report back. Sadly it'll be a few weeks as I'm about to go away on business :(

Cheers, GD.