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