Intro to Food Science: Exam 2 Full

Vocab Cards

legume

- dried beans and peas such as kidney beans, navy beans, pinto beans, split peas, etc.

-nutritionally valuable staple foods that are great sources of calories, proteins, complex carbs, and fiber

lectin

- toxic compound that is a hemagglutinin that clump red blood cells found in legumes

-removed by cooking legumes

trypsin inhibitor

- toxic substance found in legumes that prevents protein digestion and removes the benefit of the high proportion of protein in legumes

-removed by cooking legumes

tofu

-hot soymilk added with a compound that will cause it to gel, commonly nigari or calcium sulfate

nigari

compound that mainly consists of magnesium chloride that causes hot soymilk to gel

actin

-a muscle fiber protein that is partly responsible for muscle contraction and the tenderness of meat

-spherical molecules that bind to form a structure similar to a string of beads

-two strings form a thin filament

myosin

-a muscle fiber protein that is partly responsible for muscle contraction and the tenderness of meat

-shaped like a golf club and arranges in clusters that create thick filaments

-filament runs along center and head pokes out from side

muscle fiber

a single muscle cell made up of myofibrils grouped together and is covered by a sarcolemma

sarcomere

-basic unit of a muscle protein that contains actin and myosin molecules

-many together form one fibril and control muscle contraction

fibril

-sarcomeres arranged end on end (z line to z line)

-bundles of these make up muscle cell

sarcolemma

-membrane surrounding muscle fiber (bundle of fibrils) that is equivalent to a cell membrane

connective tissue

ground substance with embedded fibers of collagen and elastin that is a component of animal tissue

collagen

-a major protein of connective tissue that is white in color and has a structure that looks like 3 twisted ropes

-doesn't stretch

-converted to gelatin when heated

elastin

a stretchy, major connective tissue protein that is yellow in color and prevalent in muscles that are frequently used

marbling of meat

connective tissue that is within the muscle that's surrounding the first stage of meat cells

select cut of meat

the standard cut of meat with the least amount of connective tissue, similar to the choice cut

choice cut of meat

has more connective tissue than the select cut and less connective tissue than the prime cut, similar in amount of connective tissue to the standard cut

prime cut of meat

the cut of meat with the most connective tissue and marbling

rigor

-a process that happens hours after slaughter

-actin and myosin link to form very stable cross-links that decreases the length of the sarcomere and makes the muscle very rigid and increases the tough ness

-the actomyosin complex remains after rigor passes because there is no longer energy that allows the relaxation of the muscle fibers

myoglobin

-protein containing Fe++ with 4 nitrogens and a water that gives meat a purplish-red color

-older animals have more

oxymyoglobin

-protein that contains Fe++ with 4 nitrogens and O2 that gives the supermarket red color of meat

-oxygen replaces the water in myoglobin when myoglobin is exposed to oxygen

metmyoglobin

-protein that contains Fe+++ with 4 nitrogens and an OH that gives the brown color of meat after sitting for a few days

-happens when iron is oxidized to Fe+++

denatured globin hemichrome

-protein that causes the grayish-brown pigment when meat is cooked regardless of the original color

-Fe+++, 4 nitrogens, H2O, and denatured globin

nitric oxide myoglobin

-pigment found in cured meats that causes the meat to turn pink due to being submerged in a solution containing nitrite

-seen with ham and corned beef

crustaceans

-type of invertebrate shellfish that has a hard exoskeleton and is generally aquatic

-filter feeders

-crabs, lobster shrimp

mollusks

- shellfish invertebrates with soft, unsegmented bodies that are often protected by a hard outer shell

-one of he most diverse groups in the animal kingdom

lateral muscle in fish

-edible part of the fish that is found on the side of the fish

-light in color that is low in myoglobin

-one of two main muscles in fin fish

dark muscle in fish

-muscle on the top/back of fin fish that is relatively high in myoglobin and fat

-has a stronger flavor than the lateral muscle

-one of two main muscles in fin fish

braising

- a moist heat cooking method where the meat is first browned to generate colors and flavors then added to a small amount of liquid to simmer or cook in oven at a relatively low temperature for a fairly long time

-method behind pot roasts and stew meat

-used for tougher cuts of meat

roasting

-a dry-heat cooking method that heats food by surrounding it with hot, dry air in a closed environment or on a spit over an open fire; similar to baking, the term is usually applied to meats, poultry, game, and vegetables

-place a chunk of meat on a rack and insert a thermometer

-typically cooked at 325 F -350 F or 225 F- 250 F for a longer period of time

poaching

-cooking delicate foods like eggs in liquid that is simmering at the lowest temperature possible for a longer period of time

-preserves the moistness of the food with a gradual cooking process

trimethylamine

-produced when deterioration begins by the bacteria that is on the surface of fish and contaminates the inside of the fish converts trimethylamine oxide

-causes the fishy smell

canthaxanthin

-pigment that is added to the diet of farmed salmon and trout to create the reddish-orange color similar to the one created by the astaxanthins found in wild salmon and trout

astaxanthin

naturally occurring pigment that causes a reddish-orange color found in wild salmon and trout due to the small crustaceans that the fish eat in their natural habitats

emulsion

a dispersion of one liquid in another when the molecules of the two liquids are immiscible

immiscible liquid

when the two substances in a mixture will not mix together

oil in water emulsion

-droplets of oil are the dispersed phase and floating around in water which is the continuous phase

-milk is an example

water in oil emulsion

-droplets of water are the dispersed phase and floating around in oil which is the continuous phase

-butter is an example

emulsifier

a compound with both water-soluble and fat-soluble portions that can attract fats and oils into water, combining them by having multiple molecules line up at the interphase

phospholipid

-a glycerol + 2 fat-soluble fatty acids + 1 water-soluble phosphate

-typically act as emulsifiers in food systems

-lecithins are examples

sorbitan monostearate

-emulsifier used in the food industry

-hydrophobic and hydrophilic because of the two components

sorbitan

a sugar alcohol and has OH groups around the molecule, making it water-soluble

monostearate

one stearic acid (fatty acid) that is fat-soluble

creaming (of an emulsion)

An unstable emulsion in which fat globules rise to the top of an emulsified mixture. The best example is milk straight from the cow, because fat rises to the top of the milk, creating a layer of cream. There is no coalescing occurring, just a higher amount of fat molecules on the top of the solution.

breaking (of an emulsion)

An unstable emulsion in which fat globules coalesce with each other, forming separate layers in the solution. Pockets and layers forming from unstable emulsions coalescing.

lecithin

major phospholipid in food, commonly found in egg yolks, that is a common emulsifier

vitelline membrane

-the membrane surrounding the egg yolk and forms a ropey structure toward the end of the membrane called the chalaza

chalaza

the twisted, rope like structure in an egg that keeps the egg yolk center that is connected to the vitelline membrane

ovalbumin

-Major protein in egg white that is important for the coagulation of eggs on heating, the gelling of other foods to which eggs are added, and the foaming properties of egg white

-denatured by heat and whipping

ovomucin

Rather fibrous protein occurring in thick white more than the thin white; protein contributing significantly to the viscous, gel-like texture of thick raw white

lysozyme

defensive protein in the egg white that breaks the cell walls of certain microorganisms, killing them

ovmucoid

defense protein in egg white that is a trypsin inhibitor that prevents bacteria from digesting egg white protein

avidin

defense protein in egg whites that binds biotin and prevents microorganisms from using the biotin to grow in the egg white

conalbumin

defense protein in egg white that binds iron and inhibits the growth of microorganisms that need iron to survive

lipoprotein

-primary proteins in egg yolk

-protein with some lipid attached

-responsible for the gelling of egg yolks when frozen

homogenization

mechanical process that prevents cream from rising to the surface of milk by breaking the fat globules into much smaller fat globules that are so small they no longer rise

casein

majority of the proteins in milk, contain a lot of calcium and phosphorous (PO4-) that integrally bound into the caseins, alpha, beta, gamma, and kappa caseins are aggregated together into micelles

kappa casein

arranged on the outside of the micelle and have water-soluble tails, a protein, main reason that the micelles remain stable and suspended throughout the milk, the tails/hairs prevent other micelles from bumping into each other and linking/precipitating

casin micelle

alpha, beta, gamma, and kappa caseins (all separate proteins) aggregated together

acid curd

a solid curd that forms when acid is added to milk, brings protein it isoelectric point so the casein micelles can begin to clump together, not as dense as chymosin curd (paneer cheese, cottage cheese, cream cheese)

whey

liquid that drains off of the curds made from caseins

whey proteins

proteins that are left after you've made a curd from the caseins, the proteins that are in the liquid that drains off of the curds made from caseins. Beta lactoglobulin, enzymes (lipase)

beta lactoglobulin

whey protein that has amino acids containing sulfur, contributes to a cooked flavor of milk when the heated because the sulfur groups on the amino acids can be split off

sunlight off flavor in milk

reaction between riboflavin and methionine that give a characteristic off flavor to the milk

bran

outside coating of a cereal grain, 15% of the weight of the grain, high in cellulose, good source of fiber and B vitamins

endosperm

center part of a cereal grain, about 83% of weight of a cereal grain, primarily composed of starch and some protein

germ

the part of the cereal grain that is going to sprout and grow, about 2-3% of the weight of the grain, high in fat, high in protein, contains some vitamins and minerals

aleurone layer

layer of cells, one cell thick, that separates the bran from the endosperm.

nixtamalization

soaking corn in an alkaline solution because it makes it easier to remove the pericarp (bran) and easier to grind up the pericarp because it breaks down the hemicellulose. Also releases niacin when soaking in alkaline solution.

corn grits

corn that's been dried and ground into larger pieces than the cornmeal, can be refined

corn meal

corn that's been dried and ground, different sizes of cornmeal, can be refined

popcorn

small kernels of corn exploded by heat, moisture content needs to be about 11-14% for enough steam pressure for the kernel to pop

malt

Sprouted barley. When water is added to the environment that barley grains are sitting in, add heat so the barley grains sprout and then are dried out to become malt. Used to make beer and bread. Sprouted barley generates large amounts of amylase that break the starch into sugar

pearled barley

Refined barely that has bran and germ removed. Used as ingredients in soups and stews and casseroles.

steel cut oats

Made by taking intact oat grain and cutting it into 3 or 4 fairly large pieces.

rolled oats

Oats that have been steamed until they become soft and put them through rollers that have flattened them. Regular, quick, and instant oatmea

refining grains

Removes bran and germ. Cereal is easier to eat without bran and it is hard to remove bran without removing germ

polishing rice

Rice that has been refined (remove bran and germ) and undergoes another step of removing the aleurone layer. Makes the rice whiter

converted rice

Parboiled rice. Rice is steamed or boiled for a little while before they refine it and some of the constituents of the bran and germ migrate into the endosperm. Gelatinize the starch in the aleurone layer and makes it stuck to the endosperm so the rice is slightly more yellow from the pigments in the bran, germ, and aleurone layer.

Farina

Chunks of wheat endosperm

flour improvers

Bleaching the flour by adding oxidizing agents (chlorine dioxide, potassium bromate) which increase the strength of the gluten matrix (same effect that aging the flour does).

hard flour

Relatively higher in protein. Range 10-14% protein. All-purpose flour, bread flour, durum wheat flour (semolina).

soft flour

Relatively lower in protein. 7-10% protein. Cake flour or pastry flour

durum wheat (semolina)

A species of very hard wheat with a particularly high amount of protein. When used to make flour it is called semolina. Used for making higher quality noodles or pastas. Has a strong hard structure

bread flour

Strong flour that is used for making breads, hard rolls, and any product that needs high gluten for a strong texture.

all-purpose flour

Made from hard and soft wheat, its moderate protein content gives good results for most recipes. This is the most-used flour in American kitchens.

pastry flour

Soft flour that is not as strong as bread flour and not as delicate as cake flour.

cake flour

Soft flour with a low gluten content; a very soft, smooth texture; and a pure white color.

elastic dough

Stronger dough that bounces back when spread out.

plastic dough

Weaker dough, press it out and it will stay

disulfide bond

sulfur to sulfur bond and some of the bonds that are holding protein together in the gluten network

sulfhydral group

found on amino acids on the protein molecules found in the mix of gluten.

gluten

Balance between elasticity and plasticity.