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LESSON 1.2 WORKBOOK What's in your food besides food?

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LESSON 1.2 WORKBOOK What's in your food besides food?
LESSON 1.2 WORKBOOK
What's in your food besides food?
DEFINITIONS OF TERMS
Food additive — A chemical,
or chemicals, added to food to
improve it flavor, appearance or
shelf life.
GMO — Genetically modified
organism . An organism in which
the genetic material has been
altered in a way that does not
occur in nature.
In the previous lesson we described the characteristics of what makes something food,
and learned about some differences between
processed and whole foods. In this lesson we
will discuss ‘things’ that make it into your food
that don’t add any nutritional value. This includes
some of the major food additives, pesticides,
antibiotics, hormones and GMO foods. You will
learn why additives are used and debate their
pros and cons. For example, additives can preserve food, reducing food waste and food cost,
but they may also negatively impact our health
and the environment.
The purpose of intentional food additives
For a complete list of defined
terms, see the Glossary.
Wo r k b o o k
Lesson 1.2
Figure 1: Food additives have four main
purposes.
The introduction of many additives into our food
occurred alongside our modern day adoption of
food processing. The act of processing foods can
sometimes alter the taste and texture of foods,
or decrease the amount of beneficial nutrients in
the end product. Intentional food additives are
mainly used to make the food more palatable or
enticing to us, to increase the shelf life of food,
and to add essential nutrients (see the figure on
the left). You can identify intentional food additives
because they will be listed under the ingredients
on the Nutrition Facts panel. Below we will discuss
some commonly used intentional food additives.
1. Intentional food additives are used
for all of the following except:
aa. To make our food more
transportable over long
distances.
bb. To make our food taste better.
cc. To make our food grow faster.
dd. To make our food safer to eat.
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14
LESSON READINGS
Additives can increase the tangible aspects of foods
DEFINITIONS OF TERMS
Bran — A portion of the wheat
kernel that contains B vitamins
and fiber. The bran is included
in whole wheat fiber.
Endosperm — A large portion
of the wheat kernel that is used
to produce white flour. The
endosperm contains most of
the protein and carbohydrates
in wheat.
Food preservative — A substance added to a food product
to prevent spoiling, either by
preventing microbial growth,
oxidation, or early ripening.
Germ — A small portion of the
wheat kernel that is the sprouting section of the seed. The
germ contains B vitamins and is
included in whole wheat flour.
For a complete list of defined
terms, see the Glossary.
Wo r k b o o k
Lesson 1.2
The tangible aspects of food are those parts that we can quantify: crop yield, shelf life and nutritive value.
One major class of additives is food preservatives. Some common food preservatives that you may see
on a food label are EDTA, sodium benzoate and citric acid. By using food preservatives, less food spoils
before it gets to us, preventing food waste. Before grocery stores and restaurants were commonplace
people grew and preserved most of their own food, and food rarely traveled far distances. These days, we
rely on farmers and food manufacturers to bring food to us, meaning food has to travel longer distances
and be stored in warehouses and trucks on the way to our kitchens. This would not be possible without
the invention of additives to preserve food. In general, food preservatives can be grouped into three
categories:
1. Preventing bacterial or fungal growth – These preservatives work by inhibiting the growth of
microbes. For example, sodium benzoate is added to acidic, water containing foods like sodas or
pickles, and creates an environment where bacteria and yeast cannot grow.
2. Protecting the food from oxidation – Antioxidants are used to stop the chemical breakdown of
food that happens when the food is exposed to air. Oxidation is why cut apples turn brown. The
same antioxidants will often times work both inside and outside of our bodies, like those we get from
our diet: Vitamin C (ascorbic acid) and Vitamin E (tocopherols).
3. Preventing fruits and vegetables from ripening too quickly
– Enzymes in produce that cause ripening can be stopped by
changing the pH of the food. Acids like citric acid or ascorbic acid
are often added to foods for this purpose.
Nutrients are sometimes added to a food product to make them
healthier. When some foods are processed they lose nutritional value,
so food companies will add key nutrients back into the food. Consider
the steps involved in turning wheat into flour: after being harvested, the
fibrous bran and a nutritious part of the wheat grain called the germ
is removed, leaving only the endosperm to be ground down into flour
(Figure 2). This flour is sometimes bleached to give light, white fluffy
flour you may use to bake cookies or cakes, causing further loss of
vitamins, minerals and fiber. Because wheat flour is highly consumed,
in 1996 the U.S. government mandated the addition of iron and the
B vitamins folic acid, riboflavin, thiamin and niacin to all non-organic
wheat flour. This allowed the food processors to continue to make their
product without putting the U.S. population at risk for nutrient deficiencies. Other examples of food fortification are the addition of vitamin D
to milk and iodine to salt.
Bran!
Endosperm!
Germ!
Figure 2: During wheat
processing, the germ and
bran are removed, and
the endosperm is ground
down into flour.
2. Some food additives make us
healthier:
aa. True.
bb. False.
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15
LESSON READINGS
Some additives can increase the non-tangible aspects of foods: color, flavor and texture
Color
DEFINITIONS OF TERMS
Cardiovascular disease ­— Also
called heart disease. A disease of
the heart or blood vessels.
Hypertension — Abnormally
high blood pressure.
For a complete list of defined
terms, see the Glossary.
Wo r k b o o k
Lesson 1.2
The non-tangible aspects of food are those characteristics
that we can sense, like the look, taste or texture. For example,
food colorings make food look more appetizing without
altering the flavor. Imagine the colors of some of your favorite
processed foods: bright orange cheese flavored chips, colorful candies, green mint flavored ice cream, chances are these
foods get their colors from chemical food coloring. Synthetic
food colors are created in a laboratory and have names like
Yellow #5, whereas natural food colors are derived from
plants, like beet juice or turmeric.
Figure 3: Food additives can be
used to create a more appealing
color that mimics freshness.
Flavor
Flavor enhancers like sugar, salt and monosodium glutamate (MSG) are added so you enjoy the food
you’re eating, and to make you want more! Imagine eating potato chips with no added salt, flavors (like
nacho cheese, or ranch flavoring) or MSG– you would probably get bored of eating them pretty quickly.
Salt and MSG are called flavor enhancers because they make other flavors taste better. This means that
even if you are eating something that you don’t consider salty, food manufacturers may still include salt
or MSG in the final product to make it taste better. In the United States, most of our dietary salt intake
comes form eating highly processed foods, which has been linked to hypertension and cardiovascular
disease. You can determine if there is a lot of salt in your food by looking at the Sodium content on the
Nutrition Facts panel.
Figure 4: Common sources of
added sugars in the American diet.
Soda, energy and sports drinks are
a top contributor.
Sugar is often added to processed foods to make
them sweeter, but identifying if your food has any
added sugars can sometimes be tricky because sugar
has so many names. For example, sugar is glucose,
sucrose, maltose, fructose, cane sugar, corn syrup
and high fructose corn syrup. These can all be found
in the ingredients of processed foods, and they are all
added sugars. Additionally, non-caloric sweeteners like
aspartame, sucralose or stevia have become popular
food additives because they have the benefit of making
a food sweeter without adding calories. Because added
sugars offer calories with no helpful vitamins or minerals,
3. How would a macaroni and cheese
pasta meal prepared without any
additives compare to a boxed
version with additives? They would:
aa. Taste the same.
bb. Look the same.
cc. Have a similar number of
calories.
dd. Have the same shelf life.
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16
LESSON READINGS
it is recommended that we limit eating calories from added sugars to 100 calories a day for women, and
150 calories a day for men.
Texture
DEFINITIONS OF TERMS
Emulsifiers — A substance
that stabilizes a blend of fats and
water.
Pasteurization — Heating a
food or beverage to a specific
temperature for a set length of
time to kill harmful microorganisms.
Pesticide — A substance used
to destroy insects harmful to
crops.
Stabilizers — A substance that
prevents or inhibits a chemical reaction, usually added to maintain
a certain texture.
Thickeners — A substance
added to a liquid to make it firmer.
Viscosity — A measure of fluidity or stickiness. Honey or pudding is more viscous than water.
For a complete list of defined
terms, see the Glossary.
Wo r k b o o k
Lesson 1.2
Figure 5: Gelatin is
often added to thicken
foods.
The last types of intentional food additives are those that alter the
texture or viscosity of foods, like emulsifiers, thickeners and stabilizers. You may recognize these additives on your food labels as gums,
gelatins, pectins or lectins. These additives can help to maintain the
structure and physical properties of food products, which is important
when it is going to undergo freezing or high temperatures from canning
or pasteurization. When we cook food at home, we don’t usually use
the same emulsifiers, thickeners or stabilizers that the food industry
uses because we are cooking food in small batches to be consumed
quickly.
Unintentional food additives
Accidental, or unintentional food additives become a part of food through some aspect of production or
packaging, and have no function in the final product. These food additives are not listed on the Nutrition
Facts panel, therefore the consumer has no real way of knowing whether they are in their food. Some
unintentional food additives can also be considered a food contaminant, something that will be discussed
more in the next lesson.
Increased food production tactics bring new additives
GMOs, pesticides and herbicides
In an effort to increase crop yield farmers often employ a variety of tactics
that may inadvertently introduce food additives into your diet. Through
genetic engineering, some seeds have been modified to make them
easier to grow or to increase their nutrients or flavor; these are called
genetically modified organisms, or GMOs. For example, farmers may use
GMO seed varieties that are resistant to pesticides and herbicides, so
when the crop is sprayed the GMO plant will survive, but the insects and
weeds will die. While this technology has made farming more productive,
it has led to more prolific herbicide and pesticide use. Many people are
concerned that these chemicals may find their way into the foods that we
eat and can negatively affect the environment.
Figure 6: Pesticides, like the ones
this crop duster is
dispersing, can end
up in our food.
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17
LESSON READINGS
Antibiotics and growth hormones
DEFINITIONS OF TERMS
Antibiotic — A medicine or
chemical that destroys or inhibits
the growth of microorganisms.
BPA — Bisphenol A. A synthetic
compound found in plastics used
to store food or beverages.
Hormone — A chemical message that is produced by one tissue in the body and transported
in the blood to another tissue.
For a complete list of defined
terms, see the Glossary.
New methodologies to enhance livestock growth have also been adopted, including the widespread use
of hormone injections and antibiotics in animal feed. Some hormones, like recombinant bovine growth
hormone (rBGH) are used to increase the production of milk in dairy cows, while other hormones are used
purely to speed up the animals’ weight gain. Although there is no way to measure differences in milk from
rBGH treated cows, many people are concerned about potentially harmful impacts on people. Antibiotics
are also used to increase the rate of animal growth. While the reason is currently unknown, cattle grow
faster when administered a constant low dose of antibiotics, making the practice enticing for the beef
industry. Like rBGH, the levels of antibiotics used are very low and measuring differences in the beef
treated with antibiotics is challenging. Still, many people are concerned about the unknown, potentially
negative impacts on people. For example, the agricultural industry is currently the top user of antibiotics,
which has been cited as a contributing factor for the alarming spike in antibiotic resistant bacteria strains.
Processing contaminants
Once foods are harvested, other production steps may accidentally introduce contaminants into our
foods. Plastics and metals from processing equipment or packaging can sometimes leach into the food.
For example, BPA is a plastic widely used for bottles and the lining of cans that may disrupt normal
hormone signaling in our bodies. Since this discovery, the food industry has decreased its use of BPA in
their packaging.
Step in Food Production
Selection of crops
Growth of crops or livestock
Processing of food
Packaging of food
Possible Additive(s) Introduced
GMOs
Pesticides, herbicides, hormones, antibiotics
Food coloring, preservatives, thickeners,
stabilizers, nutrients
Plastics, heavy metals
Figure 7: Summary of intentional and unintentional (in italics) additives can be added to
our food at many steps throughout food production.
Food additives can be controversial
Wo r k b o o k
Lesson 1.2
For all of the benefits food additives bring, why not add them to all of our food? Food additives minimize
waste and make foods more accessible to regions of the world where food doesn’t easily grow. Unfortunately, not all food additives are safe, and some have even been made illegal after scientists found they
4. Unintential food additives can be
used:
aa. To make our food more
transportable over long
distances.
bb. To make our food taste better.
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18
LESSON READINGS
were detrimental to human health. Additives may find their way into our food for decades before we realize
they are unsafe, mostly because scientists did not have the resources to test safety when the additive was
first introduced. For example, most food safety trials are done over a short period of time, and the additive
may only have negative health impacts after being consumed over many years.
Food additives are GRAS
DEFINITIONS OF TERMS
FDA — Food and Drug Administration: A federal agency
responsible for monitoring trading
and safety standard in the food
and drug industries.
GRAS — Generally Recognized
as Safe. A substance that is
generally recognized among
qualified experts as being shown
as safe under the conditions of its
intended use.
For a complete list of defined
terms, see the Glossary.
While the additives that are in use today have been deemed by the
Food and Drug Administration (FDA) to be Generally Recognized
As Safe (GRAS), the safety of every additive has not been thoroughly researched. Although scientific studies are required to test
the additive under a limited set of conditions, some additives we use
today may be deemed unsafe in the future. This is in part because
there is no way to positively test for a lack of negative health
impacts. So unless negative impacts arise, the FDA has no scientific
evidence against the use of the additive. In essence, the GRAS
classification means ‘not proven unsafe’ rather than ‘proven safe’.
Figure 8: Food colorings
are responsible for making
many processed foods an
appealing color, but may be
detrimental to our health.
Additionally, when food additives are being tested for safety they are usually tested alone, without other
additives. This is not how we eat additives in a food product, and mixing additives could lead to reactions
that create damaging chemicals. Therefore, scientists may determine that a food additive is not unsafe
under certain conditions, but can never prove its safety. Because this is the case, the FDA uses the term
GRAS.
Some food additives are no longer used because of consumer backlash or health concerns. For example
the use of DDT, which was one of the original pesticides used after World War II, was found to interfere
with normal hormone signaling and might lead to cancer, so its use has been discontinued under most
circumstances. Likewise, formaldehyde was once used to preserve foods, but upon the discovery that it
is a potent carcinogen, its use in the food industry has ceased. In 1950, the food coloring Orange #1 was
banned after several children became sick after eating Halloween candy dyed with the additive.
The US allows more food additives than other developed countries
Wo r k b o o k
Lesson 1.2
Because the FDA requires solid evidence that a substance is unsafe for human consumption before it
bans that substance, some additives banned European countries are still used in the United States. For
example, some food colorings have been banned in Europe and products containing food dyes in Europe
are now required to have a label that warns consumers of an association between artificial food coloring
and hyperactivity in children. In addition, many countries have banned the growth or importation of GMO
crops, including several European countries, Saudi Arabia, Algeria, Thailand, Sri Lanka, and others.
5. All of the following are challenges
the FDA faces in determining the
safety of food additives, except:
aa. It is difficult to determine what a
food additive is.
bb. Multiple food additives are often
used together in a single food
product.
cc. The health consequences of an
additive over a lifetime cannot be
easily studied.
dd. It is difficult to prove the lack
of an effect of a substance on
health.
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19
STUDENT RESPONSES
Find a processed food around you to analyze. Look at the Nutrition Facts panel and determine what additives are in the food.
What types of unintentional food additives do you think may be in that product? Describe how that food was made, and what
steps it went through to get from the farm to you.
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Remember to identify your
sources
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Wo r k b o o k
Lesson 1.2
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20
TERMS
TERM
For a complete list of defined
terms, see the Glossary.
Wo r k b o o k
Lesson 1.2
DEFINITION
Antibiotic
A medicine or chemical that destroys or inhibits the growth of microorganisms.
BPA
Bisphenol A. A synthetic compound found in plastics used to store food or beverages.
Bran
A portion of the wheat kernel that contains B vitamins and fiber. The bran is included in whole wheat fiber.
Cardiovascular Disease
Also called heart disease. A disease of the heart or blood vessels.
Emulsifier
A substance that stabilizes a blend of fats and water.
Endosperm
A large portion of the wheat kernel that is used to produce white flour. The endosperm contains most of the
protein and carbohydrates in wheat.
FDA
Food and Drug Administration. A federal agency responsible for monitoring trading and safety standard in
the food and drug industries.
Food Additive
A chemical, or chemicals, added to food to improve it flavor, appearance or shelf life.
Food Preservative
A substance added to a food product to prevent spoiling, either by preventing microbial growth, oxidation, or
early ripening.
Germ
A small portion of the wheat kernel that is the sprouting section of the seed. The germ contains B vitamins
and is included in whole wheat flour
GMO
Genetically modified organism. An organism in which the genetic material has been altered in a way that
does not occur in nature.
GRAS
Generally Recognized as Safe. A substance that is generally recognized
Hormone
A chemical message that is produced by one tissue in the body and transported in the blood to another
tissue.
Hypertension
Abnormally high blood pressure.
Pasteurization
Heating a food or beverage to a specific temperature for a set length of time to kill harmful microorganisms.
Pesticide
A substance used to destroy insects harmful to crops.
21
TERMS
TERM
DEFINITION
Stabilizer
A substance that prevents or inhibits a chemical reaction, usually added to maintain a certain texture.
Thickener
A substance added to a liquid to make it firmer.
Viscosity
A measure of fluidity or stickiness. Honey or pudding is more viscous than water.
For a complete list of defined
terms, see the Glossary.
Wo r k b o o k
Lesson 1.2
22
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