Making Friends With Those Little Enzymes
"The biology of cheese accurately reflects
the biology of nature. Its reactions for the most part, except on
cheese surfaces, occur in a confined almost airless environment in which
millions of microbes struggle toward some progressive goal, usually
that of keeping alive."
(Cheese and Fermented Milk Foods
, Kosikowski, Volume I, p. 417)
What do you mean?
You milk your cow or goat or sheep and carefully carry the milk to the
milk vat. Within 24 hours, you slowly heat this milk to the right
temperature and add the starter cultures. You gently handle the curds
through the rest of the process and then you put the cheese in the cave
to age. Slowly, over time, the cheese develops that "picante" flavor
and silky texture you love so much.
that's the way you make your cheese, congratulations and you can stop
reading now! You are treating your lipase friends with the respect they
deserve and they will serve you well.
Now, picture this
- You go to the store and buy pasteurized milk
because in the area where you live, you can't buy raw milk. You
patiently and carefully do everything you can to make your cheese
properly. You put it in the aging "cave" you have made and wait for
many months. You try your cheese, and it's good, but not like the
cheese you love so much. Where is the flavor?
Well, to be blunt, your little lipase friends were killed when your milk was pasteurized. Simple as that.
sorry for your loss. If you don't yet know who your lipase friends
are, let me introduce you- little lipase enzymes swim around in real
milk, stalking the big huge fat globules. They have one purpose in
life- to attach themselves to the fat globules and break them apart.
This releases fatty acids which creates the sharp "picante" taste in
cheese (particularly in Blue, Feta and the Italian cheeses.)
milk is treated roughly (churned or agitated), the fat globules get
broken. The lipase enzymes (ever vigilant) are just waiting for that
opportunity to attach themselves to the broken part and begin their
job. If they begin working before the milk is turned into cheese, the
cheese will not age properly. (Areas of it go rancid before the rest
has even developed flavor.) This is why cheesemakers handle their milk so carefully.
So, you ask- if pasteurization kills the
lipase enzymes, how come my milk goes rancid after I leave it in the
refrigerator and go away for a month?
Well, this is because bacteria also create their own lipase. There are
some bacteria that thrive in refrigerator temperatures. They are
called psychrotrophic bacteria. This bacteria secretes a lipase that
can penetrate and break up even an undamaged
fat globule. This again increases the chance of rancidity in the cheese during aging. (This is the reason we warn you against using milk that has been stored for a long time.)
What is lipase?
Lipase (pronounced lie-paze) is one of at least 60 enzymes living in
real milk. (The exact amount of lipase in the milk depends on the breed
of animal and their diet.) Each enzyme has it's own specific
function. Lipase enzymes attack the fat globules and break them down.
This releases free fatty acids. When this happens the way it is
supposed to, during the ripening of the cheese, it gradually increases
the "picante" flavor of the cheese. It also makes the texture smooth
for cheesemaking comes from either calves, kids, lambs or combinations
of these. (It also comes from plants, but these plants produce such
small quantities of enzymes that historically it has not been practical
to extract them.) The exact way it is made is proprietary, but, in
general, the pre-gastric glands at the base of the animal's tongue are
dried and ground into a fine powder. Yes, this is not for vegetarians.
I saw an article on the Planet Green website which mentioned lipase:
Who knew the dirty little secret behind
something called lipase? It's an enzyme from the stomach and tongue
glands of calves, kids, and lambs found in some vitamin supplements.
(Planetgreen.com, Mickey Z., July 29, 2009)
In recent years, more and more use is being made of microbial lipases.
There is even a Kosher microbial lipase which should be available soon.
We'll keep you posted on that.
How do I know when to use it?
These are the main reasons to use it:
1. If you are using pasteurized milk.
2. If you are using cow's milk to make a cheese that is traditionally made with goat's milk (like Feta).
3. If you want any cheese you are making to be more flavorful.
Which one should I use?
As I mentioned, there are many kinds of lipase available. We carry two of the most commonly used:
This is a mild, delicate flavor. You would use it in your Mozzarella, Asiago, Feta, Provolone, Blue and Queso Fresco.
This is a sharp, more "picante" flavor. You would use it is your Provolone, Romano and Parmesan.
How do I use it?
You will need to determine how much to use, according to your flavor
preferences, but we do not recommend using more than 1/4 teaspoon for
2-3 gallons of milk. By the way, please do not think that if you want
more flavor, you should add more lipase. It is not the amount of lipase
that determines the flavor, but the action of the lipase. So, if you
want more flavor than you are getting from the sharpest lipase, age your
cheese longer or change other factors such as the type of milk, the
type of culture, or the temperature and humidity in your "cave."
is always added to the milk before it starts to coagulate. So, if you
are making a fresh cheese (where the starter and rennet are mixed
together), you add it before the starter. (That goes for any cheese,
like a lactic acid cheese, where the curds coagulate quickly from the
action of the starter.)
If you are making a cheese with rennet that is separate from the
starter, you need to add the lipase right before you add the rennet.
(This assures that the lipase does not interfere with the starter.)
Always dissolve your lipase in chlorine-free (or distilled) water before adding it to your milk (up to 1/2 cup of water).
How do I store it?
Keep it dry and store it in the freezer. It will be OK for up to a
month of shipping time, but then it should be frozen. It will keep for
up to 6 months at full potency. Then, it will slowly get weaker.