Fats are
possibly one of the most controversial ingredients available to a cook or
baker. Each fat has it’s up side and its
down side. For our purposes here, I’m
going to break this down into three basic types; animal fats, plant fats, and
oils.
Before I
get into the specific types, I’m going to give a brief overview of what it
means for a fat to be saturated, unsaturated, or polyunsaturated. A saturated fat means that the whole chain
of the fat molecule is totally straight.
This creates a problem when our bodies are trying to break them
down.
Think of
the fats as magnets. If all the fats are
totally straight magnets, it is going to be very easy for them to line up and
stick together. This will make it much
more difficult to break them apart since they are stuck together over a very
long length. This is sort of the
opposite problem of what we saw in sugars.
Sugars that are easily to break down are bad, since they get stored as
fats. In this case, fats that are easy
to break down are good since we can use them as an energy source easier.
An
unsaturated fat is a fat molecule that has one point on its chain that does not
have a full set of bonds. Let me try and
simplify that a bit. Fats have a structure that is made up of Carbon atoms. Each carbon atom is connected to 4 other
atoms that are Carbon, Oxygen, or Hydrogen.
What happens in an unsaturated fat is that one of the Carbon atoms is
only connected to 3 other atoms instead of 4.
Now I don’t want to get into the specifics as far as chemistry is
concerned, but the fact that there are only 3 connections makes the lower part
of the molecule stick out at an angle.
Since part of the molecule is now sticking out, it becomes more
difficult for the fat molecules to stick together. It’s like trying to get a bunch of bar
magnets to stick together when half of it is bent at a 45° angle; you can probably do it, but they won’t stick together as
strongly as they would if they were just straight. This means that our bodies are able to
separate and break down the fats easier.
Polyunsaturated
fats are the best! It means that the fat molecule is unsaturated in more than
one place. This is the same concept as
above, but now you have a bunch of fats together that are bent into all kinds
of weird angles. If you had magnets like
that, it would definitely be difficult getting them to stick together. As a result, our bodies have a much easier
time breaking these bad boys down and using them as an energy source.
Animal
Fats
Animal fats
are classified this way since they are made from animal products. The two most popular animal fats that you
will encounter are lard and butter, both of which are delicious! Now, a lot of
talk has gone into which types of fat are healthy and which ones are
unhealthy. People have argued back and
forth that animal fats are better, or plant fats are better. Personally, I am a fan of animal fats (at
least as far as solid saturated fats are concerned) and this is for one reason. Aside from a few exceptions, animal fats are
naturally present in their solid form, that is, they were solid to begin with
and we did not have to do anything chemically to get them that way.
Butter is
probably my preferred fat as a baker.
The reason for this is because it has been created from milk. Since it has a basis in milk, it is not a
pure fat so to speak, but it does contain all the goodness from the milk within
the milk solids. Sure you can clarify
your butter to get ghee, and cook with that.
It is still delicious and has a wonderful clarity to it. I can see why some cooks prefer to do this,
but as a baker I would never do so.
Butter is, as I was saying earlier, naturally solid. Because of this fact, there is a mix of both
saturated, unsaturated fats. Now, there is a lot more saturated fats than
unsaturated fats (since it is a solid fat), but that’s okay, it tastes
phenomenal. French bakers have used
butter for centuries. It does not have
the same ability to make pastries puff up as high-ratio shortening does, but
sometimes it’s more about the taste than the presentation. Besides, as I’ve said before, if we’re going
to do something, let’s do it right!
The other
animal fat that you can use is lard, which is rendered from Hog fat. This is a pure fat and seems to have a nearly
infinite shelf life. While not as delicious as butter, it has the ability to be
heated to a significantly higher temperature without smoking since it doesn’t
have those pesky milk solids that tend to burn.
For a long time, lard was actually used in deep fryers at McDonalds for
those delicious golden fries. It
actually amuses me a little bit when they do their experiments on how long the
fries will last. Of course they will
last for months without going moldy, they are so deeply embedded with delicious
fats that they have an anti-mold shield in place. Anywho, you will also find lard in use at old
school bakeries and donut shops. The
reason why you cannot duplicate their exquisite taste is most likely a result
of the fact that you probably wouldn’t use lard in your products. Is lard worse for you than butter? You bet!
It’s made up of completely saturated fats, but at least it is from a natural
source. One of the things I will get
into later is the difference between long chain and short chain fats.
Plant
Fats
Okay, so in
plant fats, well, solid plant fats, we have shortening and margarine. Shortening and margarine are pretty much cut
from the same block, except, like the difference between butter and lard, there
is water in margarine. I think that the
original argument was that margarine is better for you than butter since it is
made from the goodness of plant oils, canola, olive, etc. The problem, however, is that in order to go
from oil to a solid fat, it was necessary for the creators to artificially
saturate the fats (called hydrogenation).
So as we were talking about in the beginning, polyunsaturated fats are
essentially oils. Their structure is so
bent out of shape that they are unable to stick together, thus they simply
float around in oil form. What hydrogenation
does is to force Hydrogen atoms onto the Carbon atom that only has 3 bonds to
make it bond to a 4th atom.
Thus, the chains straighten and create a solid fat. Woohoo! The only problem is that
hydrogenation will take a polyunsaturated fat and turn it into a saturated
fat. Now we have a fat that is extremely
difficult to break apart, and is now bad for your health (just like lard).
The last
thing I want to mention about margarine is that it essentially has the same
amount of fat as butter. Now you may
have seen a lot of reduced fat or zero fat spreads out there. While these are fine for putting on your
toast in the morning, you definitely do not want to use them as a baking
substitute. The reason why the spreads
are lower in fat is because they contain significantly more water. Basically you’re just paying for them to add
water to your product. These spreads are
able to maintain their shape only because gums have been added to them to
maintain their cohesiveness.
The
exception here is coconut oil. Coconut
oil is actually solid at room temperature (well, depending on your room
temperature…). There was a controversy
recently regarding the use of coconut oil.
A lot of “experts” were saying that it is bad for you due to the large
amounts of saturated fats. True, I agree
that there is indeed an alarming amount of saturated fats contained within it,
however, these fats are actually short chains.
Plants and animals will tend to create long chain and short chain
fats. Basically, the chain length will
be determined by however much glucose the organism chooses to add onto each
chain. The difference however is to look
at what it would be like to pry apart bar magnets that are two inches long
versus bar magnets that are 12 inches long.
It is much easier to break apart a small one versus a large one, and the
same is true with these fats. A good way
of seeing this for me was the fact that during the winter, when the house is
about 70-74°F, the jar of coconut oil is
solid. During the summer, however, when
the house it at about 76-78°F, the jar
was completely liquid. It really does
not take as much energy to break apart the fats in coconut oil versus the other
solid fats.
Oils
Oils, as I
was saying earlier, are just unsaturated, or polyunsaturated fats. As with everything, unless you specifically
purify it, there will be a crossover of color and flavor. Just look at the light green, strongly
flavored Olive Oil, and the yellow barely flavored Canola Oil. There is a huge amount of oils available to
you, from nuts oils, to vegetable oils.
Whichever one you choose will depend on your preferences and needs. Just be aware that if you choose to use a
strong oil, like sesame oil or truffle oil, a very little bit will go a long
way.
When
cooking, oil is your friend. It is easy
to coat a pan, or pot and can be heated to very high temperatures. Some of the specialty oils are so expensive
that they are generally not used in large amounts. Instead they are often used as finishing oils
or inside salad dressings. Other oils
tend to smoke at a low temperature and are usually not used for cooking. Peanut oil, canola oil, vegetable oil and
corn oil are all very stable oils that are, or were, commonly used in the
industry.
When
baking, oil is sort of your sketchy friend.
Sometimes it comes through for you, and sometimes it does not. For example, Oil can be an easy substitution
into a fluffy cake recipe (just look at pancakes), oil is even used in small
quantities in making bread. Do not,
however, use oil in cookies or any baked product that needs its fat source for
leavening, like a puff pastry.
How do
Fats Work in Baking?
I think the
biggest thing that people normally wonder about is that nice flaky crust on a
pie or pastry. While a lot of this is a
result of proper methodology, the type of fat we use also has a lot to do with
it. You may have seen that a normal pie
crust recipe directs you to break up the fat into small pea sized pieces. When you roll out the dough, these small
pieces actually flatten out and create little flattened blobs of fat in the
dough. When you bake your crust, the fat will create a shield on the top and
bottom of a layer. The evaporation of
the water in the crust and create steam this will cause the dough to puff
up. Since parts of the dough are
shielded because of the flatten disks of fat, they will create little air
pockets. The areas that are not shielded
will absorb the water and then dry out.
All of these little air pockets throughout the crust is what we refer to
as flakiness.
The second
thing that you may be wondering about is the role of fat in cookies. When you are making cookies, the fat will
coat the pieces of flour and sugar and make a nice crumb since they are kept in
little separate pockets. Now this is the
key that I like to tell people. The more
you mix your cookie dough, the more they are going to spread out. I have seen people walk away from the mixer
and they end up with little cookie crepes.
The reason for this is quite simple.
As you mix the fat into the cookie dough, it begins to coat the
particles. As you continue to mix it,
more and more particles will get coated.
This is okay, however, once too many particles are coated, they lose
their ability to stick together since gluten strands are unable to form. Whenever I make cookies, after I add the dry
ingredients, I mix it just until things are pretty much incorporated, then I
finish it off by hand.
How does
Fat Work in Cooking?
Let me just
say that as far as cooking is concerned, fat is a beautiful thing. Without fat, cooking would be rather bland
and have a slightly unpleasant texture. Primarily,
we use fats, oils in particular, to coat pans or pots so that food won’t stick
to them. We also end up using fats to
add flavor, such as a nice brown butter to toss pasta or spaezle in.
This next
example goes back to baking a little bit, but it is for a savory dish. You will notice that when you are done making
chicken stock you have a nice layer of fat on the top. DON’T THROW IT OUT!!! In addition to the fact
that this is pure fat, it also tastes quite good. If you are thinking of making a Quiche or
some sort of stuffed pastry for dinner, use your left over chicken fat! I did this several times while I was working
at a café and people loved it. If you
are now cringing at this fact, let me just say that my years working in the
restaurant industry has taught me that the reason things taste so good, is
because they are totally loaded with fat. YUM!
Another
example would be if you have rendered off some fat, say from the leftover
chunks of fat from butchering a leg of pork.
Just melt it down and add it to a dish for some intensely good
flavor. When I was in culinary school we
were making a pork stew, I forget what it was called, but it is a French
Canadian classic. Anyhow, I just couldn’t
get the full bodied flavor I wanted, so I poured in about ½ a cup of rendered
pork fat. Talk about amazing! Of course
I did this a little bit wrong.
Technically I should have used the fat to make a roux, and then use that
to thicken the stew. Either way, you can
maximize the money you spend on food by utilizing all the parts. It also gives you a great flavor that may
actually remind you of the cooking you remember when you were young.
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