In the United States and Canada, sulfites are not allowed on red meat. Sodium bisulfite does such a good job of color fixing, sulfited ground beef can be rotten and you can’t tell by looking at it. For safety and because vitamins can be affected, the FDA has an absolute prohibition against sulfites in meat. However, the rule doesn’t apply to other ingredients that may be mixed into the meat. For instance, sausage may legally contain corn syrup, molasses, or wine. In other parts of the world ( especially in the UK and Australia ), sulfite preservatives are allowed in ground beef and sausages. So, watch out when you are traveling.
Fish is another story. Sulfites are an allowed preservative for fish all around the world. Theoretically, in American stores, sulfited fish must carry a warning somewhere near the fish display, but I’ve never seen one. And, a sulfited fish has bitten me more than a few times, especially swordfish. On the other hand, I have had good luck with salmon either from the supermarket or in restaraunts. Whether declared or not, ocean shrimp are almost always preserved with sulfite to prevent a black spotting fungus. Farmed shrimp have an additional twist; they are fed meal containing sulfite preservatives. Restaurants can further complicate matters by deep frying shrimp in a common vat with vegetables. The shrimp sulfites leak into the oil and contaminate otherwise clean vegetables. At my house, I substitute fresh avocado slices for shrimp and make a "shrimpless" cocktail. But, beware of cocktail sauces which contain preserved horseradish, wine and lemon juice concentrate. I mix up my own sauce using organic ketchup, rice vinegar, fresh lemons and refrigerated horseradish colored with beet juice.
Gelatin is pure protein processed to promote the
gelling of liquids. In other
words, Jell-O. Most of the gelatin produced in the United States is
made
from pigskin, although cattle hide and bones are also used. The first
step
in making gelatin is a softening soak in sulfur dioxide and water. Why
are
we not surprised? Gelatin is used in many foods to build body and
improve
texture. Lowfat yogurts use lots of gelatin to make up for the missing
milkfat.
It is usually quite difficult to estimate the amount of gelatin in a
food
by just reading the label. However, it is quite easy to look at the
table
below which gives recommended percentages of gelatin for various types
of
foods. Gelatin typically has an effective sulfur oxide concentration of
45
ppm. An alternative to gelatin is fruit pectin. In the
past,
some forms of pectin were preserved with sulfites; however, today all
forms
of pectin are sulfite free.
Gelatin Table
Food Using Gelatin | % Gelatin | Serving | Gelatin (g) | SOx (ug) |
Aspic salads | 15 % | ¼ cup | 9.0 grams | 405 ug |
Gelled meats | 3.0 | 2 ounce | 1.7 grams | 76 |
Gummy Worms | 3.0 | 5 pieces | 1.1 grams | 50 |
Low Fat Spreads | 2.0 | 1 Tbs | 0.3 grams | 14 |
Gelatin Dessert | 1.5 | ½ cup | 1.8 grams | 81 |
Icing and Frosting | 1.0 | 2 Tbs | 0.3 grams | 14 |
Syrups | 1.0 | ¼ cup | 0.6 grams | 27 |
Yogurt | 0.5 | 1 cup | 1.1 grams | 50 |
Sauces and Gravies | 0.5 | ¼ cup | 0.3 grams | 14 |
I was quite surprised to discover that cheese contains sulfites. In
hindsight,
I have had some problems with Italian dishes like ravioli but never
suspected
the cheese. Then I ran into a very tasty white cheddar that clearly
caused
headaches. The nice folks in the dairy department at UC Davis told me
that
all cheeses contain low levels of sulfite created naturally during the
aging
process. But they did not have any numbers to pin things down. So, I
had
to add cheese to my list of sulfured ingredients and run some
experiments
to determine concentrations.
Most cheese is made using the same basic steps
developed by our forefathers
5,000 years ago. Milk is separated into solid curds and liquid whey by
adding
a little acid and enzyme borrowed from a cow’s tummy. As the mixture
is pressed, salt is added, the whey is drained and the curds become
more
firm. The compacted curds are left to age and bacteria sharpens the
flavor.
Cheese may be categorized as fresh, soft, hard and dry. Fresh cheeses
are
not aged. Soft cheeses are aged but remain creamy either naturally or
by
processing. Hard cheeses include cheddar, jack, mozzarella, swiss and
gouda.
Dry cheeses are strongly aged with very low moisture like parmesan and
dry
jack. I have included sour cream in the table because of its
similarity
to fresh cheeses. ( Note that regular plain yogurt is not
included
in the table because it is very low in sulfites if it is pure without
corn
starch and gelatin. Plain yogurt is a good substitute for sour cream if
you
are very sensitive to sulfites like me. Also, kefir cheese is actually
a
form of yogurt and a good substitute for cream cheese if you are
watching
your sulfites. On the other hand, high protein Greek yogurt is not as
good
since the sulfites rise as it is concentrated during processing. I find
Greek
yogurt to have about the same level of effective sulfur oxide as
cottage
cheese. )
Common Cheese Table
Class | Cheese | Age | SOx |
Code | Water | Prot | Fat |
Fresh | Cottage, lowfat | Cottage | 0.5 ppm | CHC | 82 % | 12 % | 1 % |
Queso Fresco | Fresh | 1.0 | CHF | 42 | 21 | 21 | |
Ricotta | Fresh | 1.1 | CHF | 74 | 11 | 8 | |
Soft | Cream Cheese | Fresh | 1.4 | CHF | 54 | 8 | 35 |
Sour Cream | Fresh | 1.2 | CHF | 71 | 3 | 21 | |
American | Mild | 1.9 | CHM | 39 | 22 | 31 | |
Hard | Cheddar, mild | Mild | 2.0 | CHM | 37 | 25 | 33 |
Cheddar, sharp | Sharp | 2.5 | CHS | 37 | 25 | 33 | |
Cheddar, white | Extra | 4.0 | CHX | 37 | 25 | 33 | |
Monterey Jack | Fresh | 1.5 | CHF | 41 | 24 | 30 | |
Mozzarella | Mild | 2.1 | CHM | 9 | 27 | 17 | |
Roquefort | Sharp | 3.2 | CHS | 42 | 21 | 29 | |
Swiss Cheese | Mild | 2.1 | CHM | 37 | 28 | 27 | |
Dry | Parmesan | Extra | 5.5 | CHX | 18 | 42 | 30 |
So, how do we estimate the sulfites? Since there are hundreds of
different
cheeses made all over the world in thousands of factories and farms, we
must
make some generalizations. First, the concentrations listed in the SOx
column
are the values determined from my headache tests on common brands found
in
a California supermarket. If you sort the data, five groups may be
loosely
related to cheese age: Cottage, Fresh, Mild, Sharp and Extra Sharp.
Then,
each group can be assigned a three letter SOx code. Some cheeses will
be
typically in only one of these groups while others may be represented
in
several. For instance, cheddar can be mild (aged 2 months), sharp (aged
6-9
months) and extra sharp (aged 1 year or more). If the exact type or age
of
a cheese is not specified on the ingredient label, "mild" would be a
good
guess, since mild cheeses are generally less expensive. The six age
groups
are summarized in the table below. For each group, a representative
cheese
is used as an example for a typical serving size and resulting amount
of
effective sulfur oxide. As usual, the typical serving sizes are
designed
for dieting midgets. My typical servings are larger and sometimes
result
in a headache.
Basic Cheese Groups
Age | Code | SOx |
Example | Serving Size | SOx ug |
Cottage | CHC | 0.5 ppm | Cottage | ½ cup (113 g) | 56 ug |
Fresh | CHF | 1.2 | Sour Cream | 2 Tbs (30 g) | 36 |
Mild | CHM | 2.0 | American | 1 slice (21 g) | 42 |
Sharp | CHS | 3.0 | Sharp Cheddar | 1 inch cube (28 g) | 84 |
Extra | CHX | 5.0 | Parmesan | 2 teaspoons (5 g) | 25 |
Well, if cheese can have sulfites, maybe we should look more closely at
other
flavorful foods. A couple of interesting candidates might be sourdough
bread
and eggs. Sourdough bread is made using a starter yeast that is aged.
Thinking
this might affect bread much as aging affects cheese, I ate four slices
of
DiCarlo Extra Sourdough Bread. Guess what, no headache. If sourdough
bread
has any sulfur oxide, it must be under ½ ppm. Bread lovers may breathe
a sigh of relief.
What about eggs? If you’ve ever smelled a rotten egg, you know sulfur is in there somewhere. So, I tested eggs. No, I didn’t suck them out of the shell. I’m very cultured. I smashed them into a pan and scrambled them. A typical egg without the shell weighs about 50 grams. It takes 3 scrambled eggs to give me a headache. However, if the eggs are prepared over easy, only 2 eggs are required for a headache. Apparently, some of the sulfites are lost or converted during the cooking process. Since scrambling exposes more of the egg to heat and atmospheric oxygen, scrambled eggs wind up with a slightly lower sulfite concentration. Averaging over various methods of preparation, the effective sulfur oxide concentration of eggs is about 1.0 ppm. This is a low value if eggs are just another ingredient in a recipe, but as the main course in a hearty breakfast, the total amount of sulfur might be significant.
Before my tests, I didn't suspect that eggs were a problem. It takes over 24 hours for the headache to appear, about the same delay as starch. Apparently, whenever I woke up with an egg headache, I suspected the previous night’s dinner, not the previous day’s breakfast. I’m wiser now, but also a bit sadder. What am I to do; I really like omelets, especially cheese omelets. If I stop feeling sorry for myself long enough to be creative, eggs and cheese are not much of a problem. For instance, I can have an omelet made with one egg, a little fresh cheese (like Queso Fresco Mexican cheese) and lots of vegetables. I can have baked potatoes topped with butter and plain yogurt (no starch, no gelatin and not Greek) instead of sour cream. And, cheeseburgers can be made with a spoonful of kefir chesse. I know it sounds a little weird and such a diet does make you feel like burning incense and chanting a mantra. But, what's a poor boy to do?
Rybett Controls |