Chapter 7: Protein

Denaturation/Turnover

Tertiary structure causes changes. Acid, alkaline, heat, enzymes, and agitation cause denaturation

Main Protein Allergies

6 categories: peanuts/tree nuts, eggs, fish/shellfish, soy, wheat, milk Account for 90% of all food allergies

Kwashiorkor

Acute onset due to minimal amounts of PROTEIN and moderate energy deficiency, usually in 1-2 year olds, big belly and edema in feet

Complete Protein

Adequate amounts of all the essential amino acids, Animal proteins such as meat, poultry, fish, eggs, and milk, contain ample amounts of all 9 essential amino acids, except gelatin

Non-essential Amino Acids

Body can produce these so consumption isn't needed

Essential Amino Acids

Can only be taken in by food

Complementary Proteins

Combining plant proteins to compensate for a limiting amino acids- example lysine is limiting in grains but add legumes to make up for it

Structure of Protein

Contains H, O, C, N, Composed of amino acids (nitrogen group/amine, acid group/carboxyl, hydrogen, side chain/r-portion)

Conditionally essential amino acids

Essential during infancy, disease, or trauma

Positive Nitrogen Balance

Growth, pregnancy, recovering from illness/injury, athletic training, increased secretion of hormones like insulin, growth hormone, and testosterone

Neutral Nitrogen Balance

Healthy adult meeting calorie and protein requirements

Incomplete Protein

Inadequate amounts of essential amino acids- plant proteins don't contain adequate amounts of essential amino acids. except soy, quinoa, buckwheat, flax

Protein & Health Concerns

Long-term affect on kidneys, low intake of fruits/vegetables, high intake of saturated fats, cholesterol (usually found w/ protein)

Marasmus

Occurs over time due to low amounts of ENERGY, protein & other nutrients, usually in infants

Protein Organization

Primary: Sequence of Amino Acid Chain Secondary: Due to H or S bonds among Amino Acids Tertiary: Occurs from folding & determines protein function Quaternary: Occurs when multiple proteins join together

Functions of Protein

Produce vital body structures (collagen, actin, and myosin) Maintain fluid balance (return blood to capillaries), contribute to acid/base balance (some act as buffers and some act as ion transporters), forming hormones, enzymes, and neurotransmitters, contribute to immune function (antibodies), form glucose via gluconeogenesis, provide energy (4kcal/g)

PDCAAS

Score given to foods that helps determine how much our body will use Example: PDCAAS of wheat: 0.40 Protein Content: 3 grams 1.2 grams count towards DV%

Limiting Amino Acid

The essential amino acid in smallest supply in a food or diet in relation to body needs

Negative Nitrogen Balance

inadequate protein intake, inadequate energy intake, fevers, burns, or infections, bed rest, amino acid deficiency, increased protein loss, increased secretions of hormones like thyroid and cortisol