UNIT 5 Flashcards
lipids
- organic compounds that are soluble in organic solvents
- composed with carbon, hydrogen, and oxygen (but have high proportions of hydrogen and less of oxygen)
glycerol
- a three-carbon compound with three alcohol (hydroxyl) groups, each of which is esterified with fatty acid
fatty acid
- aliphatic chains with a carboxylic acid (-COOH) functional group
saturated fatty acids
- fatty acids that do not have any double bonds between the individual carbon atoms
monounsaturated fatty acids
- fatty acid that has a single double bond
polyunsaturated fatty acid
- tow or more double bonds
hydrogenation
- the addition of hydrogen atoms to unsaturated fatty acid, causing the double bonds (unsaturated) to become single bonds (saturated)
complete hydrogenation
- all double bonds being converted into single bonds
- “hardens” the shortening unable to use for baking
partial hydogenation
- some of the double bonds are saturated and some of the double bonds are reconfigured from the cis form into the trans form
- results in a partially hydrogenated fat, or trans fat
- conducive to baking
omega-3 fatty acids
- polyunsaturated fatty acids that have their first double bond on the third carbon from the methyl end of the fatty acid chain
- essential to human diet
omega-6 fatty acids
- polyunsaturated fatty acid that have the fist double bond on the sixth carbon atoms from the methyl end
- when consumed in moderate amounts: regulate metabolism, stimulate growth of skin and hair, and maintain bone health
phospholipid
- the resulting diglyceride (2 fatty acids) when one of the fatty acids in a triglyceride is replaced by a phosphate group
proteins
- complex polymers of amino acids
amino acids
- organic molecules containing carbon, hydrogen, oxygen, and nitrogen
peptide bond
- covalent bond between the nitrogen of one amino acid with the carbon of the carboxylic group of the adjacent amino acid
- amino bond
primary structure
- linear arrangement of amino acids in a protein chain
secondary structure
- foldings or coilings within a protein structure that are stabilized by hydrogen bonding
tertiary structure
- final three dimensional structure of protein that involves numerous noncovalent interactions between amino acids
quaternary structure
- how multiple peptide chains are aggregated together by hydrogen bonds, disulfide linkages, and salt bridges into a final specific protein shape
complete proteins
- proteins containing all essential amino acids
incomplete proteins
- proteins that lack one or more essential amino acids
- plant proteins
protein complementation
- combining two or more different protein sources to have a better amino acid balance than when consuming either protein alone
food foam
- two-phase system where air is dispersed in a continuous liquid or solid phase
protein denaturation
- the disruption of bonds that make up the tertiary and secondary structure of proteins.
- Can occur through addition of heat, alcohol, acids, salts, enzymes, and mechanical shear.
protein coagualtion
- congealing and separating out of denatured proteins
- egg whites stiffen upon beating or harden upon heating
enzymes
- biocatalysts that speed up the rate of biochemical reactions, without getting destroyed themselves
- not all proteins are enzymes, but all enzymes are proteins
- each enzyme catalyzes a specific type of reaction
enzymatic browning
- process whereby the enzyme polyphenol oxidase (PPO) catalyzes the oxidation of phenols into brown-colored melanins
nonenzymatic browning
- the most common type of browning in processed foods
- this reaction occur at elevated temperatures and include the caramelization of sugars and Maillard reactions between amino acids and sugars
carmelization
- a series of reactions involving dehydration, isomerization, and polymerization, resulting in the formation of polymeric caramels
- caramels are responsible for the dark brown colors of certain foods
maillard reactions
- series of nonenzymatic reactions between reducing sugars and amino acids at high temperatures that result in browning
vitamins
- organic, nutritionally essential compounds that are mostly heat labile
- classified as water soluble or fat soluble
enrichment
- adding back of nutrients after processing of a food
- • Flour Enrichment Act of 1972: addition of THIAMIN, RIBOFLAVIN, NIACIN, and IRON to flour
fortification
- addition of certain nutrients to a food as a means to prevent specific nutrient deficiencies in the population
mineral
- an element other than carbon, hydrogen, oxygen, and nitrogen that is present in food
- heat stable and are classified as major or trace, depending on their concentrations in plants and animals
saturation
- the number of hydrogen atoms a fatty acid chain is holding
- more hydrogen atoms attached, the more saturated the fatty acid
point of unsaturation
- no hydrogen attached and a double bond occurs
butyric acid
saturated
- found in butter
- 4 carbon atoms, single bond
stearic acid
saturated
- found in beef
- 18 carbon atoms, single bonds
palmitic acid
saturated
- found in palm oil and cocoa butter
- 16 atoms, single bonds
oleic acid
monounsaturated
- found in olive oil and canola oil
- 18 carbon atoms, one double bond
linoleic acid
polyunsaturated
- oilseeds such as canola and soybean
- 18 carbon atoms and 2 double bonds
linolenic acid
polyunsaturated
- soybean and hempseed
- 18 carbon atoms but contains 3 double bonds
cis form
unsaturated fatty acids
- hydrogen atoms on the double bond are on the SAME SIDE as the double bond
trans form
unsaturated fatty acids
- hydrogen atoms are on OPPOSITE SIDES of the double bond from one another
- higher melting point
- naturally in meat, poultry and processed milk
emulsifiers
- substances that keep water and fat dispersed in one another (help them to mix together)
lecithin
- a phospholid found in egg yolk
sterols
- large molecules consisting of interconnecting rings of carbon atoms, with side chains of carbon, hydrogen and oxygen
cholesterol
- important in the structure of cell membranes
winterization of fats
- a process to produce salad oils that do not crystallize
- oils can become cloudly at lower temperature
- invloves lowering the temperature of oil
rancidity
- the chemical spoilage that commonly occurs with fats and fatty food
fat replacers
- ingredients that replace some or all of the functions of fat and may or may not provide energy
artificial fats
- zero-energy fat replacers that are chemically synthesized to mimic the sensory and cooking qualities of naturally occurring fats, but are totally or partially resistant to digestion
