Bitter Chevre

[hbhokie]

I'm a long time lurker here, but now I need some help!  I have a small goat dairy in Virginia and have recently scaled up from home cheese making to using a rented licenses cheese making facility.  The facility I am renting (2 days a week) is at another farmstead goat dairy. 

The problem I'm coming up against is that my larger batches of chevre are coming out bitter.  I've noticed the problem for three weeks now.  Thats close to 60 pounds of bitter chevre!  I'm making in 14 gallon batches using pasteurized fresh goat milk (most times the milk is only 2-24 hours old). 

When I was making chevre at home, I would pasteurize 3-3.5 gallons on top of the stove using the 145 degrees for 30 minute method.  Cool the milk (pot in a sink of cold H20) to 86-90 degrees.  Then culture with Flora Danica at a rate of 1/4 tsp. per gallon of milk.  After the culture had rehydrated for a few minutes, I would add the rennet (single strenght animal) at a rate of 2 drops per gallon of milk, diluted in 1/4 cup cold H20.  Allow to ripen for 8-24 hours (depending on schedule), cut the curd, and hang in bags made from bed sheets.  After draining 24 hours, the cheese was awesome.  I had been making chevre this way twice weekly for over a year.  I had gotten pretty good and consistent at it.  I got excellent reviews and decided to try my hand at this on a larger scale.

So, now to my scaled up version.  I pasteurize the milk around 6:30 am using a 14 gallon vat pasteurizer.  I'm still using the 145 degree for 30 minute method.  When the milk cools back down to 86-88 degrees, I culture with 3.5 tsp of Flora Danica (still at a rate of 1/4 tsp. per gallon) and add rennet (still single strengh animal) at a rate 10 mL per 14 gallons.  Because of my schedule at the rented facility, I let it ripen for 8 hours, cut the curd, and hang in bed sheet bags again (about 3 gallons per bag).  The cheese drains for 24 hours.  When I unbag the cheese, it is slighly wetter than my homemade version but not enough to worry about.  When I taste the cheese before packaging it, I dont notice any bitter taste; however, after the cheese is cooled off in the fridge, it picks up a bitter after taste.  I'm bummed out, but I think we can fix this. 

Here are my thoughts so far: 

Do I need to cut back on the starter culture or rennet.  I'm using the same rate of each as I was in the smaller batches; however, does the amount of culture or rennet not need to increase in a linear relationship to the volume of milk?

On another note, I've been making feta too (and a raw cows milk tomme) in 14 gallon batches at the rented facility, and the larger batches seem to be coming out equal to or better than the smaller batches.

Thanks for any help you can give!

HB

[linuxboy]

What is your ambient room temp and final moisture of the chevre after draining? Excess moisture and too high of a temp speed up protein breakdown, leading to bitter peptide formation prematurely. It's like giving maturation a jump start.

[hbhokie]

Pav

Ambient temp is around 74 degrees.  How would I go about finding out the final moisture level of the cheese?

To add to the conversation, I talked with another local goat cheese maker this morning about scaling up batches, and she mentioned that you cannot increase the culture and rennet at the same rate you increase your batch size. 

Thanks

HB

[linuxboy]

Hmm, that's an OK room temp, a tad high but not terrible. Must be your rennet combined with high moisture.

Are you really adding in 10 ml for 14 gallons of milk? Or was that a typo? At what pH are you adding the rennet? Or if no way to know, how long after culture addition?

Moisture test is hard to do without a lab, and difficult to ask based on feel. Maybe you can tell me comparatively? How does it compare to other commercial chevres you've had?

Your friend is kind of right. You can't scale it exactly based on teaspoon and similar measurements. But you can scale it exactly if you're adding based on commercial equivalencies of DCU or volume rennet/starter per weight of milk.

[hbhokie]

Pav

My homemade chevre is drier than many commercial chevres and a little more dense.  This is what I'm after.  My customers like that.  The flavor had been really clean until I scaled the batch up.

You read correctly, I used 10 ml of single strength animal rennet for 14 gallons of milk.  Im guessing from your reaction that is part of the problem.

HB

[hbhokie]

I'm adding the rennet about 5 minutes after culture.  Just enough time for the culture to rehydrate and stir it in.

[linuxboy]

Pav

My homemade chevre is drier than many commercial chevres and a little more dense.  This is what I'm after.  My customers like that.  The flavor had been really clean until I scaled the batch up.

OK, got it. I'm wondering why you used .1 ml (2 drops) for 1 gallon before and now are using (.7 ml). This will give you huge moisture retention and very rapid protein breakdown, unless you crash chill the chevre immediately after bagging. Even then that's a lot of rennet.

You read correctly, I used 10 ml of single strength animal rennet for 14 gallons of milk.  Im guessing from your reaction that is part of the problem.

You should be using, maximum .25 ml rennet per gallon. Even that's too high for me.

I'm adding the rennet about 5 minutes after culture.  Just enough time for the culture to rehydrate and stir it in.

I like my savory chevre similar to yours, low moisture (cheesecake chevre I make with higher moisture). To do that, I add rennet at 6.0-6.25 after ripening for a while. But that's my style. You can add rennet shortly after, it makes for a different cheese. It does influence mouthfeel a little. To get that goaty acidic light flint, you need to rennet at 6.0-6.25.

[Brie]

Linux--are you talking about minutes or hours here for the addition of the rennet?

[linuxboy]

where? 6.0-6.25? That's pH.

[TroyG]

Shoot I use .0277ml per gallon or .6ml single strength rennet for 20 gallons. My chev is very creamy and delicious! No I am not bias at all.

Of course I have been told I have magical milk. 

[linuxboy]

Yep, that's more classically farmstead French style chevre that's mostly lactic coagulation. You could use more to target a specific flavor profile. Like if you wanted to copy Mary Keehn's cypress grove products, you'd add rennet at 6.0-6.1 and bag at 4.5-4.6 and use a moderate amount of rennet. If you wanted to copy Laura Chenel's, you'd use less rennet and rennet at 6.0 and bag at 4.5. Their culture mixes are proprietary, of course, but that's how you'd hit texture and moisture targets.

Your milk cured my disbelief that Nubians can be dairy goats   j/k