Rennet - Dosage Rate For Rennet Coagulated Cheese Making

[Frumunda]

I'm wanting to buy some rennet.How much rennet would you normally need to treat a US gallon of milk?How much milk would,say, a gallon of rennet treat?

[linuxboy]

You need about 1/4 tsp rennet dissolved in 40 parts cold water for one gallon milk. In the US, rennet is standardized so 1 unit of rennet coagulates 15,000 units of milk in 45 minutes as 95 F. This is by weight. So if 1 gal of rennet weighs 9 lbs, it is enough to coagulate about 135,000 lbs of milk, which is about 15,900 gallons of cow milk.

Meaning for the typical double strength stuff you buy, if you get a gallon, it would take 30,000 gallons of milk to use it up.

[Frumunda]

Cool!That's a whole lot of cheese!It's also plenty to experiment with and allow for screw ups,as nearly all my first attempts usually result in screw ups!I'll get a small bottle first,then after the first of the month,I'll invest in a bunch!Thanks! 

[wharris]

I typically buy the 2oz size for $6.50USD here

[thebelgianpanda]

I second Wayne's suggestion, 2oz is perfect.  I'm pretty sure Wayne uses the veal rennet, but I use the 'vegetarian'.  I don't think you can lose with either.

[Frumunda]

I got a pint of the vegetable rennet,I subscribe to the school of thought that it's better to have too much than to not have enough.I'm gonna try the veal rennet after I use that up,which apparently is gonna take a while! Is there a difference in the taste of the cheese if you use the vegetable,rather than the natural?

[thebelgianpanda]

I can't tell the difference between the two, but there are people that can.  A pint is going to be serious overkill, but may come in handy if you have friends that get interested.

[MrsKK]

Remember that liquid rennet weakens with age, so you are losing out on the "economies of scale" front there.

[Cheese Head]

linuxboy, appreciate the detailed info, couple more questions . . .

When you say in US rennet is standardized, I assume you mean for the large commercial volumes like this one from large US manufacturer Cargill which I think the retail stores are re-packaging (fair enough).

But there are many variations, appreciate any other insights, if you have them? For example:

• On Wayne's link above, US based DairyConnection.com retails a single strength veal rennet and two types of double strength veg rennet (I don't know the difference between the two).
• I bought some Malaka brand rennet.
• I also bought some CHR Hansen freeze dried Rennet, probably from Brazil.
• A few of our Kiwi/Ozzie members have bought from this large Rennet Maker in NZ.
• Some of our members use Junket or other brand tablets.

Thanks, John.

[linuxboy]

Hi John,

Yep, I meant the labs test the chymosin strength and dilute with water until it's to the right standard.

Dairyconnection, from what I recall, repackages rennet from a WI supplier that usually sells to the cheesemaking companies in WI. Their two vegetable double strength rennets differ in that one is certified organic.

Most vegetable rennet is usually the cheaper (compared to animal) M. Miehei-derived one. It doesn't matter practically what type of veg rennet you buy as they work the same way. It does matter what type of veal rennet you buy because they have varying levels of pepsin and other compounds. The variation comes from the age of the animal when the rennet is obtained from it. This is one factor that influences final flavor and why some people swear by animal rennet claiming it produces a better cheese.

Freeze dried rennet works similar to junket tablets. Chymosin strength is more like 1:100,000 for the dry powdered rennet. Not sure what it is for the junket tablets.

The products Renco makes are directly comparable to European and US products, but I am not sure of the concentration. European rennet is usually 1:10,000 for single strength.

All these differences mean it is vital to not buy too much rennet because it loses strength over time. Not more than you can use in 1-1.5 years. It is also vital to get the manufacturer's data for the proper addition rate and use a dropper or similar way to measure grams or ml exactly. Especially with double strength rennet, it is easy to add too much, which can result in bitterness. At least, that's what happened to me. . Manufacturers will typically say use XX volume for YY lbs of milk. Using 8.5 lbs/gal milk, I calculate the proper volume per lb or gallon and then use that instead of the 1/4 teaspoon per gallon or similar inexact measurements. It really helps with producing repeatable results.

I have some more rennet details in my head for non-animal rennet, such as GMO vs non GMO, true coagulants made from vegetables, etc. But I have to run. I'll try to post later.

[Cheese Head]

linuxboy, thanks very much for the additional info, I have lots to learn.

FYI, I found a whole bunch of Technical Data Sheets on Manufactured cultures etc including "rennets", and I just posted them in our Library. There is a bunch of info there on the different rennets including the recommended ratios.

[Frumunda]

Ok,so I got double strength rennet,so if you need 1/4 tbsp of regular rennet to set 1 gallon of milk,then 1/8 tbsp of this will work?

[Cheese Head]

Road Rash, don;t know where you got yours, so I would go with amount recommended on package and adjust next batch based on this rounds results, if nothing on package, then contact supplier, last resort, I would go with this guideline from US based Dairyconnection.com. Rennet Best Practices here.

[wharris]

And from DairyConnection, I use the 2oz Single strength veal rennet..
I use it at the rate of .25tsp/gallon.

[Frumunda]

I got it from the cheese making online store,all the label says is that it's double strength and to only use half of what the recipe calls for,but none of the recipies here are specific about how much to use.I just guessed last night and I'm not sure I used quite enough and maybe that might be why my curds got all clumpy,I'm thinking either 1) I didn't use quite enough rennet, 2) I didn't use any sodium chloride as I was using store bought milk, 3) I didn't allow enough time for my clean break,or 4) I let the curds get too hot,or perhaps a combination of any or all of these things.