Nutrition and Composition of Food

Any substance taken into the assimilated by a plant or animal to keep it alive and enable it to grow and repair tissue; nourishment

Anything that nourishes or stimulates; whatever helps something to keep active, grow, etc◦ Webster’s New World College Dictionary – 4th edition. 1999.

Complex mixture of chemicals that an organism takes in and assimilates to:◦ Promote growth◦ Expend energy◦ Replace worn or injured tissue◦ Prevent some diseases

What is Food?

Encompasses many processes= many definitions 

The series of processes by which an organism takes in and assimilates food for promoting growth and replacing worn or injured tissues◦ Webster’s New World College Dictionary – 4th

edition. 1999.

Nutrition…

Extremely complex mixtures of thousands of chemicals

97% of food’s mass is made up of: Proteins Carbohydrates Lipids

The remainder of food consists of thousands of compounds that exist in small amounts (measuring parts per million) and are often important in:

Taste Odor Color

Vitamin and minerals also exist in minute amounts and are very important in body function.

Most Foods are Actually…

Obesity Rates

For adults, overweight and obesity ranges are determined by using weight and height to calculate a number called the “body mass index” (BMI). BMI is used because, for most people, it correlates with their amount of body fat.

An adult who has a BMI between 25 and 29.9 is considered overweight.

An adult who has a BMI of 30 or higher is considered obese.

BMI is an estimate of body fat so sometimes it can show that a person is overweight when they are not actually

Like athletes

Defining Obesity

Calculating Body Mass Index (BMI)

BMI =

Weight in pounds

(Height in inches)2

Calculate Your BMI

BMI =

( )2

Diabetes

Cancer◦Breast◦Colon

Heart disease

Liver disease

Hypertension

Stroke

Respiratory issues

Sleep disturbances

Obesity is associated with increased risk for

Rank1 Causes of death All persons

All causes 2,397,615

1. Diseases of heart 652,486

2.Malignant neoplasms (cancer)

553,888

3. Cerebrovascular diseases 150,074

4.Chronic lower respiratory diseases

121,987

5. Unintentional injuries 112,012

6. Diabetes mellitus 73,138

7. Alzheimer's disease 65,965

8. Influenza and pneumonia 59,664

Causes of Death

Source: U.S. National Center for Health Statistics, Health, United States, 2007.

“New” Food Pyramid

1. Multiply grams of fat times 9 calories per gram to get calories from fat

2. Divide calories from fat by total calories and multiply by 100 to get % of calories from fat

3. Multiply grams of saturated fat by 9 calories per gram to get calories from saturated fat

4. Divide calories from saturated fat by total calories and multiply by 100 to get percent calories from saturated fat

Calculating % Fat in Food

Quarter Pounder from McDonalds

◦ Calories – 410◦ Total fat – 19 grams◦ Saturated fat – 7 grams

Calculate the % fat and % saturated fat in the quarter pounder.

Dietary recommendations are to consume less than 10% of calories from saturated fats and keep total fat intake between 20-35% of total calories…does a cheeseburger do this?

Try It for Yourself

Food◦ Anything that nourishes or stimulates; whatever

helps something to keep active, grow, etc Webster’s New World College Dictionary – 4th edition. 1999.

Nutrient◦ Nutritious ingredient or substance in a food

Webster’s New World College Dictionary – 4th edition. 1999.

Food vs. Nutrients

Carbohydrates

Proteins

Lipids

Vitamins

Minerals

Water

Classes of Nutrients

PROTEINS

Chief organic constituent of muscle and other tissues

Major components of enzymes that regulate and carry out general metabolism and functions

Part of intracellular and extracellular structures of animals

Make up structure of many hormones and antibodies

Proteins

Nitrogen Carbon Hydrogen Oxygen Sometimes sulfur and phosphorus

All proteins contain approx 16% Nitrogen, thus when determining total protein in a food, we analyze for protein Nitrogen, then multiply by 6.25

Proteins Contain

Basic Protein Structure

COOHR

NH2

CH

R group represents any one of a variety of chemical structures that makes each protein unique.

Not all protein is made up of suitable materials to properly supply the body with what it needs

Proteins from animal products are considered high quality◦ Meat◦ Milk◦ Eggs

High quality proteins contain◦ All essential amino acids in amounts needed to

support protein tissue formation by body

Quality of a Protein

Most plant proteins are NOT considered complete

◦ Soybeans are close

Some consider them to be complete or high quality proteins

Quality…cont…

Essential ◦ Can’t be synthesized

by the body in adequate amounts

◦ MUST be supplied by the diet

Non-essential◦ Can be produced by

the body As long as there are

adequate amounts of essential amino acids being provided in diet

Essential vs. Non-essential Amino Acids

If ANY essential amino acids are missing from the diet, NO proteins formed.

WHY?? Because if the body did not stop all protein

production, cells would end up with an imbalance of proteins Seriously affect cell function

Why are Essentials Needed for Non-Essentials?

Amino AcidsEssential Amino Acids Non-essential Amino

Acids

Histidine AlanineIsoleucine ArginineLeucine AsparagineLysine Aspartic acidMethionine CysteinePhenylalanine Glutamic acidThreonine GlutamineTryptophan GlycineValine Proline

SerineTyrosine

Solubility◦Differs greatly among proteins Depends on amino acid content Depends on amino acid sequence

Properties of Proteins

Solubility of ProteinsProtein Type Function SolubilityHistones Protein replication Soluble in pure water

Albumins ovalbumin - egg white lactalbumin – milk blood albumins

Soluble in pure water

Keratin Hair and fingernails Insoluble in water

Collagen bones cartilage connective tissue epidermis

Insoluble in water

Myosin Muscle tissue Insoluble in water;Soluble in weak salt solution

Lactoglobulins Milk Insoluble in water;Soluble in weak salt solution

Wheat, glutenin, orzenin (rice0

Not soluble in water; soluble in acids or alkali

Proteins like those in muscle tissue of meats are able to bind water molecules through hydrogen bonding.

Advantageous when making ground or comminuted products◦ Hot dogs ◦ Bologna

Emulsion made with◦ Fat◦ Protein◦ Water

Product cooked (smoked)

Retains much of the moisture

Becomes palatable, attractive product

Water Binding of Protein

Primary structure◦ made up of◦ Molecular weight◦ Amino acid

composition and ◦ Sequence along the

polypeptide chain

Secondary structure◦ Shape of a coiled

helix

Tertiary structure◦ Result of the folding

of the chain over itself

◦ Three-dimensional state

◦ Very important to level of protein activity

Structure of Proteins

Quaternary structure◦ Possible of two or more polypeptide chains join

together◦ Huge tangled, complicated chain of amino acids◦ Fragile molecules

Good to be aware of these reactions when exposing product to Heat Acid Salt Other conditions that could disturb their stability

Structure of Proteins…

The change in molecular structure without breaking covalent bonds or altering amino acid sequence

Protein conformation (secondary, tertiary, and quaternary) structures can be very fragile and thus can be altered by a number of factors that can be used in food processing

Denaturation of Proteins

Denaturation usually results in the loss of biological activity and significant changes in physical and functional properties (such as solubility)

Occurs only in proteins and protein-like substances

Denaturation of Proteins cont…

Different levels of effect on individual proteins◦ Enzymes (primarily protein substances) can be

denatured which causes the biochemical function they catalyze to cease

Denaturation of Proteins cont…

Caused by many factors◦ Heat◦ Acids◦ Solvents

Ethyl alcohol◦ Concentrated

solutions of some salts

◦ Surface forces

Loss of biological activity and solubility

Irreversible gels may be formed◦ More susceptible to

enzymatic hydrolysis Makes them more

digestible

Denaturation of Proteins cont…

Practically irreversible Control of denaturation is essential to food

technology Inactivation of enzymes = storage

problems “Blanching” step in freezing and canning

of fruits and veggies done to denature enzymes

Contributes to flavor and texture of food

Denaturation of Proteins cont…

Cheeses and yogurt are direct results of denaturation of milk proteins

Cooking affects denaturation of proteins and impacts flavor of protein-rich foods like eggs and milk◦ Hardening of egg whites in frying pan = denaturation◦ Whipping of egg whites to form foam results from exposure

to surface forces◦ Many meat proteins are cooked to 134°F to 167°F =

profound changes in Texture Water holding capacity Shrinkage

Denaturation of Proteins cont…

CARBOHYDRATES

Body requires a constant source of energy◦ Carry out day-to-day

physiological functions

◦ Maintain constant body temperature

◦ Needs larger amounts to do work

Humans derive energy mainly from carbohydrates ◦ 55% - 65%◦ Can also utilize fats

and proteins for this purpose

Made up of◦ Carbon◦ Hydrogen◦ Oxygen

Carbohydrates

Carbohydrates that are important in nutrition include◦ Sugars◦ Starches◦ Dextrins◦ Glycogen

Other carbohydrates that are not digestible (fibers) ◦ Don’t supply calories ◦ Very important in

overall health of the body

Sugars are the simplest form of carbohydrates

Carbohydrates

Simplest of all sugars

Cant be broken down further by hydrolysis

Most common ones found in foods are hexoses (6-carbon sugars)

Five that occur freely in nature

◦ Glucose◦ Mannose◦ Galactose◦ Fructose◦ Sorbose

Monosaccharides

Sweetener◦ Not all sugars are

very sweet Lactose – 16% as

sweet as sucrose See table

Added for texture an appearance qualities

Contributes to viscosity◦ Consistency◦ Body◦ Mouth feel

High refractive properties◦ Shiny appearance in

high-sugar products Syrup Jellies Dried fruits

Uses in Food Processing

Water can be available for microbial use◦ Can be bound by sugar and unavailable for microbes

◦ Still offer moist product

◦ Water available for microbial use is measured Water activity (Aw)

◦ Sugars have affinity for water Suppress water activity

Jams, jellies, etc Preservative effect

Uses in Food Processing

Degree of Sweetness of Various Sugars and Other Sweeteners

Sweetener Degree of SweetnessSucrose 100Fructose 173.3Glucose 74.3Lactose 16Maltose 32Galactose 32Saccharin1 30,000 – 50,000Sodium cyclamate2 10,000Neohesperidin dihydrochalcone3 1,000,000

1 Sweet ’N Low2 formerly used as a low calorie sweetener, but since been banned due to possible carcinogenic effects3 sweetener derived from citrus – not widely used yet

Polymers◦ Compounds of many smaller molecules

Simple monosaccharides joined together by glycosidic bonds

May contain the same monosaccharides or several different monosaccharides joined together◦ When more than 10 units are joined together =

polysaccharide Most contain hundreds of thousands of

monosaccharides

Polysaccharides

NOT sweet

Responsible for Texture – including:◦ Viscosity ◦ Mouth feel◦ Consistency◦ Gelatin◦ Smoothness◦ Toughness

Nutritionally, starch is the most important polysaccharide◦ Main source of

calories in human diet

Polysaccharides cont…

Made up of two polymers (large molecule made up of repeating chemical structures)

◦ Amylose – linear compound

◦ Amylopectin – branched compound

Starch

Alpha-amylase◦ Widely distributed

in nature◦ Saliva◦ Pancreatic

excretions in mammals

◦ Plants◦ Microorganisms

Beta-amylase◦ Found almost

exclusively in higher plants

Pullulanase

Amyloglucosidase◦ Found mainly in molds

Maltase

Major Enzymes that Catalyze Starch Hydrolysis

Generally not readily soluble in cold water

◦ When heated, uptake water, swell, and gelatinize Viscosity increases; forming a paste Gel is formed when cooled

Often used to thicken foods Can be modified when combined with sugar or acid and

used in puddings

Starch

Very important◦ Starches used in products like

Canned soup/stews◦ Important because of exposure to heat for long

periods of time during canning etc. Maintain a smooth but thick texture

◦ Generally – amylase rich structures will form a stronger gel Pile of branches = amylopectin Pile of cut logs = amylase

Gel Strength

Can be treated with acids or enzymes◦ Hydrolysis of some bonds◦ Results in low viscosity

For some sauces, toppings, and gravy

Can be treated with oxidizing agents such as sodium hypochlorate◦ Results in reduced viscosity and paste clarity◦ Used as emulsion thickeners and stabilizers in

dressings and spreads

Starch…

Animal starch Produced in liver from glucose Stored in liver and muscles

◦ Available for immediate use as energy◦ Can only store limited amount

Excess carbohydrate intake = excess glycogen production = excess carbohydrate converted to fat and stored in the body as such

Glycogen

Body maintains an equilibrium between glucose (energy-producing sugar) and glycogen (can quickly be converted to glucose)

Nutritional value of glycogen in foods is minimal

Animal foods not considered a good source of carbohydrate

Glycogen…

Used as food additive for texture Not readily digested Contains 1 calorie per gram Used as “bulking agent” in low-calorie

products to ◦ Replace sugar◦ Bind water

Add to textural attributes without greatly increasing calories

Polydextrose

Includes the non-digestible carbohydrates

Water soluble◦ Cereal brans◦ Pectin◦ Lower serum

cholesterol levels Binding with bile acids

and causing removal of cholesterol in feces

Water insoluble◦ Wheat products◦ Wheat bran◦ Thought to reduce

colon cancer Increases bulk and

dilutes effect of secondary bile acids

Fibers

Cellulose◦ Makes up most of

the structural material in plants

◦ Main component of many industrially important substances Wood Paper Fibers (cotton)

In nature◦Fibers that are

very high mechanical strength

◦Insoluble in water

Pectin◦ Water soluble fiber◦ Intercellular spaces

of plant tissue

Fibers…

Gums◦ Have ability to give

highly viscous solutions at relatively low concentrations

◦ Used for Gelling Stabilizing Suspending

◦ Used in Candies Fruit sauces Syrups Toppings Spreads Baked goods Salad dressings Beverages

Fibers…

Lipids

Definition◦The heterogeneous group of substances,

associated with living systems, which have the common property of insolubility in water but solubility in nonpolar solvents such as hydrocarbons or alcohols.

Lipids…

Types of lipids◦ Fats◦ Oils◦ Waxes◦ Phospholipids◦ Sphingolipids◦ Sterols

Fats and oils◦ Contain 9 calories

per gram◦ Proteins and

carbohydrates contain 4 calories per gram

Lipids…

Glycerol esters of fatty acids◦ Ester = alcohol and acid join and produce a

water molecule. The result is an ester

Contain ◦ Carbon◦ Hydrogen◦ Oxygen

Proportion of oxygen is much less than in carbohydrates

Fats and Oils

Ester Diagram

R-OH R1-COOH R-OOCR1

Alcohol EsterAcid

Fuel foods that are more concentrated

Produce more than twice the heat energy as carbohydrates

1g fat = 9 cal. 1 g carb. = 4 cal.

Stores well in large amounts in body◦ As adipose tissue◦ Considered a great

reserve of energy for the body

◦ Health hazards of obesity Affluent societies

Fats and Oils…

Occur in foods as ◦ Lipid materials

Solid at room temperature◦ Oils

Liquid at room temperature

Variation of lipids vs. oils depends on fatty acid components

Fats and Oils

Open chain carboxylic acids Natural fatty acids most commonly found

in fats and oils almost always contains an even number of carbon atoms◦ Ranging from 4 – 28

Fatty acid chain may be ◦ Saturated

Have the maximum number of hydrogen atoms attached

◦ Unsaturated Lacking hydrogen atoms at certain points

Fatty Acids

Saturated vs. Unsaturated Fatty Acids

◦Butyric acid

◦Carproic acid

◦Caprylic acid

◦Capric acid

◦Lauric acid

◦Myristic acid

◦Palmitic acid

◦Stearic acid

Common Saturated Fatty Acids

Unsaturated fatty acids◦ Occur in both plant

and animal sources◦ More prevalent in

most oils from plant sources Corn oil Safflower oil Canola oil

Common unsaturated fatty acids◦ Oleic acid◦ Linoleic acid◦ Linolenic acid◦ Arachidonic acid

Unsaturated Fatty Acids

Monounsaturated One double bond (one

H missing)

Polyunsaturated Two or more double

bonds

Essential fatty acids◦ Must be supplied by

the diet Linoleic Alpha-linolenic

Fatty Acids…

Fatty acid components of fats and oils not only affect the melting point but also have nutritional implications◦ Saturated fats in diet

Lead to increased serum cholesterol

Oils can be “hardened”

Production of hard cooking oils

Margarines◦ Melting point is

raised Easier to transport Easier to spread on

foods

Fatty Acids…

Unsaturated fatty acids can exist in different configurations◦Because of those points of “unsaturation”◦In nature, most occur in the cis- form◦When oils are hydrogenated (hardened)

they can change to the trans- form Increase in trans-fatty acids can lead to increase in

serum cholesterol

Cis - vs. Trans- Fatty Acids

Hydrolyzed to glycerine and fatty acids◦By lipase enzymes◦In small intestine◦Eventually oxidized at the cellular level for

energy, carbon dioxide, and water

Emulsified (particles dispersed within)◦Carried to adipose tissue◦Stored

Two Paths of Fats Once Ingested

Cis – and Trans- Fatty Acids

Phospholipids, Waxes, Sphingolipids, and

Sterols

Made from◦Glycerol◦Fatty acids◦Phosphoric acid◦Often an amino alcohol

In body they are important part of cell membranes and are involved in the building of these membranes

Phospholipids

Very good emulsifiers in food industry◦Due to their polarity at one end and non-

polarity at the other◦Used in

Chocolate Salad dressing Mayonnaise

Component of egg yolks

◦Help hold stuff together (polarity)

Phospholipids…

Made from fatty acids and monohydric alcohols In body

◦ Serve as protective, water repellent coatings on tissue surfaces

◦ Functions Prevent over evaporation of moisture Prevent invasion of water from the environment into

tissues In food industry

◦ Used in some packing◦ As ingredients in some candies and confections

For texture or appearance◦ Not digestible

Waxes

SPHINGOLIPIDS◦ Sphingomyelin is important constituent of nerve and

brain tissues

STEROLS◦ Sterol cholesterols

Involved in Composition of bile salts

Play role in emulsification of fats in the intestines In other words, digestion of fats

◦ Ergosterol May be converted to vitamin D in the body under the

influence of sunlight or UV light

SPHINGOLIPIDS and STEROLS

Vitamins

Many vitamins are required in small amounts by the body

2 types◦ Fat-soluble◦ Water-soluble

Vitamins

Vitamin A

Vitamin D

Vitamin E

Vitamin K

Fat-Soluble Vitamins

Found only in animals◦Retinol

Plants contain carotene◦Vitamin A can be

produced in body◦Beta-carotene

Formed in body from yellow pigments (containing carotene)◦From many fruits

and veggies◦Especially carrots◦Also found in fats

and oils Especially in liver oils

of many saltwater fish

Vitamin A

Required for vision and resistance to infection

Epithelial cells◦Cells in the lining

of body cavities and in the skin and glands

◦Require vitamin A

Deficiency may cause◦Impairment in

bone formation◦Impairment of

night vision◦Malfunction of

epithelial tissues◦Defects n teeth

enamel

Vitamin A…

Necessary for normal tooth and bone formation

Deficiencies◦ Rickets

Deformities of bone Bow-legs Spine curvature

Tooth defects

Fish oils (especially fish liver oils) = great source

Body can make vitamin D by converting sterols (cholesterol) with use of UV light

Vitamin D

Four different forms (tocopherols)◦ Alpha-

Most common Antioxidant

Unsaturated fatty acids

◦ Beta-◦ Gamma-◦ Delta-

Enhance absorption of iron

Vitamin E

Sources◦ Corn oil◦ Cottonseed oil◦ Peanut oil

Deficiency symptoms not clearly identified in humans◦ Animal studies show

Reproduction issues Injury to CNS Growth retardation Muscular dystrophy Interference with

normal heart action

Vitamin E…

Essential in production of prothrombin◦ Compound involved in the clotting of blood

Sources◦ Cabbage◦ Spinach◦ Cauliflower◦ Liver◦ Can be synthesized by bacteria in human intestine

Antimicrobial therapies that destroy intestinal bacteria can lead to deficiencies in vitamin K

Vitamin K

Symptoms of deficiency◦ Loss of ability to clot blood◦ Humans typically get adequate amounts of

vitamin K in the diet

Vitamin K…

B1

B2

Niacin

B6

Biotin

Pantothentic Acid

Choline

B12

Folacin

C

Water-Soluble Vitamins

Also called thiamin

Involved in bodily oxidations that lead to formation of carbon dioxide

Necessary for: ◦ Nerve function◦ Appetite◦ Normal digestion

Growth Fertility Lactation

Vitamin B1

Retardation of growth

Palpitation and enlargement of the heart

Hypertension

Various effects of nerve center disturbance◦ Forgetfulness◦ Difficulty in thinking

clearly

Beri-beri◦ Affects muscles,

heart, and nerves

◦ Common in parts of SE Asia Where white rice is

the main food source

◦ In US, primarily seen in those with chronic alcoholism

Symptoms of B1 Deficiency

Sensitive to sulfur dioxide (SO2) and sulfite salts◦ SO2 destroys Vitamin

B and shouldn’t be used as preservative in foods that are a major source of the vitamin

◦ FDA and Meat Inspection laws prohibit such uses

Stable in heat in foods with a high acidity◦ Less stable in foods with

more neutral or alkaline pH levels

Sources◦ Fresh pork◦ Wheat germ◦ Cereals containing bran ◦ Beef and lamb are fair

sources

Vitamin B1…

Also called riboflavin

Makes up part of the enzyme systems involved in oxidation and reduction of different materials in the body

Deficiency◦ Growth retardation◦ Vision impairment◦ Scalding of skin◦ Lesions on mucous

tissues◦ Neuritis

Vitamin B2

Sources◦ Good

Milk Liver Eggs

◦ Fair Meats Leafy green vegetables

Sensitive to light

◦ Packaging should be considered Cardboard for milk Other light-resistant

packaging

Vitamin B2…

Part of enzyme system regulating reduction reactions in the body

Dilates blood vessels

Part of coenzyme nicotinamide adenine dinucleotide (NAD)◦ Involved in breaking

down glucose

Deficiency◦ Pellagra

Disease that causes Diarrhea Dermatitis Nervous disorders Sometimes death

Sources◦ Yeast◦ Meat ◦ Fish◦ Poultry◦ Peanuts◦ Legumes◦ Whole grains

Niacin

Part of enzyme system that removes CO2 from acid group (COOH) of certain amino acids and transfers amine group (NH2) from one compound to another

Deficiency◦ Doesn’t cause well

described disease

Sources◦ Bananas◦ Barley◦ Grain cereals with

bran◦ Muscle meat◦ Liver◦ Green vegetables

Vitamin B6(pyridoxine)

Has been taken by women taking steroid contraceptives

Has been used to treat PMS◦ Not recommended without blood tests

Vitamin B6…

Coenzyme in synthesis of aspartic acid◦ Plays a role in carbon

dioxide fixing

Sources◦ Peanuts◦ Peas◦ Beans◦ Whole cooked eggs◦ Liver = excellent source

Deficiency◦ Unusual◦ Can be tied up by

aviden Substance in raw egg

whites

◦ Been seen in feeding studies in mice

◦ Produced by microbial flora of intestines Dietary requirement is

unknown

Biotin

Required for◦ Normal growth◦ Nerve development◦ Normal skin◦ Involved in

metabolism

Deficiency◦ Rare

Sources◦ Widespread in foods◦ Animal organs, eggs,

whole wheat products, and peanuts = excellent sources

Pantothentic Acid

Sometimes listed with B vitamins

Typically consumed in adequate amounts

Produced by intestinal flora

Component of cell membranes and brain tissues

Choline

Largest vitamin molecule

Requirement for normal development of red blood cells

Deficiency◦ Acute pernicious

anemia

Cobalt is part of the structure◦ Why cobalt is

required in the diet

Some synthesized by intestinal flora but some must be consumed in diet

Vitamin B12 (cyanocobalamin)

Required for formation of blood cells by bone marrow

Involved in formation of blood pigment (hemoglobin)

Required for synthesis of some amino acids

Folacin

Deficiency◦ Some types of

anemia Pernicious

Requirement is about 1.25 times greater in pregnant women◦ May act to prevent

some birth defects

Sources◦ Liver◦ Leafy vegetables◦ Legumes◦ Cereal grains◦ Nuts

Folacin…

Required for formation of intracellular substances in the body◦ Dentine◦ Cartilage◦ Protein network of bone

Important in ◦ Tooth formation◦ Healing broken bones◦ Healing of wounds

Enhances absorption of iron

Deficiency◦ Scurvy

Spongy, bleeding gums,

Loss of teeth Swollen joints

◦ Fragile capillary walls◦ Impaired healing of

wounds

Vitamin C ( Ascorbic Acid)

Sources◦ Excellent

Orange juice Tomato juice Green peppers Broccoli Cabbage Brussels sprouts

◦ Fair Potatoes Fruits

Easily destroyed by oxidation and heat◦ Can be lost in

cooking water during processing

◦ Fortification may be necessary Before and after

processing

Vitamin C…

Minerals

Human body contains about 3% minerals

Most in skeletal system

Exist in minute amounts

Function is necessary for normal growth and reproduction

Categories◦ Major◦ Trace

Based on amounts in body

Minerals

Calcium

Sodium

Chlorine

Potassium

Phosphorous

Magnesium

Sulfur

Major Minerals

Iron Iodine Flourine Copper Cobalt Zinc Manganese Selinium

Vanadium Silicon Tin Chromium Aluminum Boron Cadmium

Trace Minerals

MinearalsMajor Minerals

Required for◦ Bone and tooth

structure◦ Function of nerves

and muscles◦ Blood clotting

mechanism

Deficiencies◦ Osteoporosis

(especially in older women)

◦ Symptoms not apparent until later in life

Other◦ Essential for calcium

absorption◦ Lactose may also help

Calcium

Required for◦ Extracellular fluids

to maintain osmotic equilibrium and body-fluid volume

Deficiencies◦ Little known except

in cases of prolonged diarrhea or vomiting

Other◦ Excess consumption

can result in hypertension

Sodium

Required for◦ Extracellular fluid –

major negatively charged ion

◦ Role in controlling blood pH

◦ Necessary for production of HCl

Deficiencies◦ Component of table

salt

◦ Never really lacking in diet

◦ Can need replenishing during times of great losses of body fluids

Chlorine

Required for◦ Present in body cells as chief intracellular cation

◦ Associated with function of muscles and nerves and with metabolism of CHO

◦ Maintaining fluid volume inside cells

◦ Maintaining acid-base balance

Potassium

Meats

Eggs

Oranges

Bananas

Fresh milk

Potassium Sources…

Other◦ Cell membranes = very permeable to K, but as

leaks out, highly active pump returns it to the cell in exchange for sodium

◦ If as little as 6% of K contained in the cells escaped into the blood, heart would stop

Potassium…

85% of P found in body is combined with Ca

Part of bodies major buffers (phosphoric acid and its salts)

Part of DNA and RNA

Some lipids contain

Key role in energy transfer

Phosphorous is Required For:

Meat

Fish

Eggs

Nuts

Phosphorous Sources:

Required for◦ Minor component of

bone

◦ Present in soft tissue cells where it is involved with protein synthesis

Deficiencies◦ Unusual

Sources ◦ Veggies◦ Cereals◦ Cereal flours◦ Beans◦ Nuts

Magnesium

Required for◦ Present in virtually all proteins

Deficiencies◦ Associated with protein deficiencies

Sulfur

MineralsTrace Minerals

May be due to poor absorption of sources found in plants

Animal sources and those found in fortified foods are more readily absorbed

Essential in hemoglobin and myoglobin

Iron – Required for:

Most common deficient trace mineral in industrialized world

Cause anemia

Amount needed is related to growth rate and blood loss

Menstruating women should take special precautions

Iron Deficiencies

Sources◦ Liver◦ Meat ◦ Eggs ◦ Oatmeal◦ Wheat flour

Other◦ Toxicity is rare but

can happen with supplement tablets

◦ 6-12 tablets can be fatal if ingested by small child

◦ Vitamins E and C aid in absorption

Iron…

Required◦ Part of hormone

thyroxine (regulates metabolism levels)

Other◦ Toxicity symptoms are

similar to deficiency (enlarged thyroid)

◦ Industry is reducing use of iodized products

Deficiencies◦ low-level

metabolism◦ lethargy◦ goiter (enlarged

thyroid)◦ rare if consuming

saltwater fish◦ iodized salt today

prevents

Iodine

Required◦ Helps prevent tooth

decay

Sources ◦ Drinking water◦ Fish

Other◦ Too much fluorine

via supplements can cause flourosis (mottling of tooth enamel)

Flourine

Required◦ Aids in use of iron in

hemoglobin synthesis

◦ Required by some enzyme systems

Deficiencies◦ Virtually unknown

Sources◦ Fruits◦ Beans◦ Peas◦ Eggs◦ Liver◦ Fish ◦ Oysters

Copper

Toxic in high concentrations

Happens when using copper utensils for storage or distribution of acidic foods (lining of tubs distributing lemonade)

Copper…Other Info

Required◦ Component of Vitamin B12 ◦ Only place known in the body

Deficiencies◦ Sufficient amounts present in foods◦ Can be absorbed from some cooking utensils

Cobalt

Required for:◦ Cofactor for more than 70 enzymes for specific

tasks in the eyes, liver, kidneys, muscles, skin, bones, and male reproductive organs

◦ CHO and protein metabolism

◦ Nucleic acid synthesis

Zinc

Deficiencies◦ Rare◦ Dwarfism◦ Gonadal atrophy◦ Possible damage to

immune system

Sources◦ Shellfish◦ Meat◦ Liver

Zinc…

Required for:◦ Normal bone

structure◦ Fat production◦ Reproduction◦ Functioning of CNS

Sources◦ Meats

Deficiencies◦ Bone disorders◦ Sexual sterility◦ Abnormal lipid

metabolism

Other◦ Adequate sources

found in most diets

Manganese

Required for:◦ Antioxidant with

Vitamin E

Sources◦ Meat◦ Seafood◦ Grains

Deficiencies◦ Anemia◦ Muscle pain◦ Sometimes heart-

failure

Selenium

Sources◦ Unpolished rice and grains

Deficiencies◦ Diseases related to connective tissue

Silicon

Required for:◦ Growth rates◦ Essential to structure of protein

Deficiencies◦ None noted

Other◦ Present in many foods

Tin

Required for:◦ Physiological role related to glucose metabolism

Sources◦ Whole, unprocessed foods

Other◦ Content decreases with age◦ Linked to adult-onset diabetes

Chromium

Roles are unknown

Deficiencies unknown

Affected parts of brains of those with Alzheimer’s have found to have excess amounts of Aluminum

Still not good to store food long-term in aluminum containers

Aluminum, Boron, and Cadmium

Natural Toxicants

Some plants can produce compounds that serve as protectors or help ensure reproduction◦ May attract pollinating insects, repel animals or

insects that may eat them◦ Can be toxic to humans◦ Some mushrooms produce specific nitrogen-

containng bases or alkaloids that cause severe physiological issues

◦ Heavy metals such as lead, mercury and arseninc Found in soils and water

Natural Toxicants

Toxin Food SourceCyanide-generating compounds Lima beans

Safrole Spices

Prussic acid Almonds

Oxalic acid Spinach, Rhubarb

Enzyme inhibitors and hemagglutinins Soybeans

Gossypol Cottonseed oil

Goitrogens (interfere with iodine binding by thyroid gland) Cabbage

Thyamine Cheese

Avidin (antagonistic to growth factor biotin Egg whites

Thiaminase (destroys vitamin B1 Fish and shellfish

Vitamins A & D methionine (toxic effects in excess concentrations) Many foods

Natural Toxicants and Their Food Sources