Matrix Definitions for Mycotoxin Testing

We know sometimes matrix names are confusing, so we've provided a quick glossary of the matrix definitions used when developing our mycotoxin test kits. Just click on the main grain to view the sub-matrix table for each.

Whole corn kernels
Corn flour
Very finely ground corn meal (note, in the UK, the term 'cornflour' actually refers to corn starch). Usually degerminated (if not, can be labeled 'whole grain'). Generally under 200 micron (70 mesh) particle size.
Corn germ
The germ portion of the corn kernel, constituting about 11% of the kernel weight; composed of about 45-50% oil and representing about 85% of the oil in the whole kernel.  Germs are removed in the wet milling process to facilitate starch extraction, whereas they are removed in the dry milling process to improve the stability of maize grain products for use as food.
Corn germ meal
Corn germ meal is what's left after corn oil is extracted from the corn germ
Corn gluten feed
Corn gluten feed is the by-product of the wet-milling of maize grain for starch (or ethanol) production. Consists mainly of maize bran and maize steep liquor (liquid separated after steeping) but may also contain distillers solubles, germ meal, cracked maize screenings, etc.
Corn gluten meal
Corn gluten meal is a by-product of the manufacture of maize starch (and sometimes ethanol) by the wet-milling process. A protein-rich feed, containing about 65% crude protein, fiber-free endosperm is centrifuged in order to separate the starch fraction and the gluten, which have different densities, resulting in almost pure starch (99% starch), and corn gluten meal.
Corn meal/ Grits/Polenta
Grits and polenta are both ground corn meal.  The term corn meal generally refers to particle sizes 300-600 microns (50-30 mesh). It is typically degerminated and bran removed, but not always (usually labeled "whole grain"). Polenta is typically medium-ground (300-400 microns); grits is typically coarse-ground (500-600 microns).
Dried distillers grains with solubles (DDGS) are a coproduct of the corn ethanol process ; after fermentation, spent grains and solubles are dried and used as an alternative animal feed valued by the livestock industry.
Hominy feed
Hominy feed is a mixture of corn bran, corn germ and part of the starchy portion of corn kernels, a byproduct of the manufacturing of pearl hominy, hominy grits or table meal.
Masa flour
To make masa (or hominy), field corn is dried (whole) and treated with a solution of calcium hydroxide (or “slaked lime,” or wood ash) -- a process called "nixtamalization." When fresh masa is dried and ground, it becomes masa flour (or masa harina). This process of treating ground corn with an alkaline solution loosens the hulls from the kernels, allowing the nutrients to be absorbed into the body easier than with regular cornmeal. And simply mixing with water creates a dough.
Complete wheatberries
Wheat bran
Wheat bran consists of the outer layers (cuticle, pericarp and seedcoat) combined with small amounts of starchy endosperm of the wheatberry.  Coarseness and starch content can vary widely
Wheat flour
Whole wheat flour - the entire wheatberry is ground to a flour consistency (<200 microns, <70 mesh)
White wheat flour
Flour milled after the wheatberry has had its bran and germ removed and the remaining portion is ground to a flour consistency (<200 microns, <70 mesh).  This material may be enriched (iron, B-vitamins, folic acid and malt).
Wheat gluten
Gluten is the natural protein portion of the wheat that is separated from whole wheat with pure water; generally in powder form and containing no starch
Wheat midds
Wheat midds (also known as wheat middlings, millfeed, or wheat mill run) is a by-product of wheat milling. During milling, about 70 to 75% of the grain becomes white wheat flour, leaving 25 to 30% (mostly bran and germ), largely destined for livestock consumption. There is wide variability in mill streams and proportions that are combined to ultimately constitute the by-product’s final composition.
Wheat red dog
Wheat red dog consists of the offal from the “tail of the mill,” with some fine particles of wheat bran, wheat germ and wheat flour. It is a source of carbohydrates, protein, vitamins and minerals, and must not contain more than 4 percent fiber.
Hulled barley, only the outermost hull removed, sometimes referred to as groats; whole barley kernels. (Pearl barley has had outermost husk and bran removed, popular for home cooking)
Malted barley
Barley that is sprouted, then dried, to encourage sugar, starch, and diastase
Rice / Rough rice
Whole rice, unprocessed; a commodities term that is used to describe rice as it comes from the field after harvest.
Rice bran
Outer bran coating that has been removed from rice
Rice, black glutinous
Glutinous rice (Oryza sativa var. glutinosa; also called sticky rice, sweet rice or waxy rice) is a type of rice grown mainly in Southeast and East Asia, which has opaque grains, very low amylose content, and is especially sticky when cooked.  Black version is actually dark purple naturally.
Rice, brown
Whole grain rice with the outer hull/husk removed
Rice, white / Rice, milled
Rice which has had the husk, bran and germ removed (milled rice, polished rice)
Rice, white glutinous
Glutinous rice (Oryza sativa var. glutinosa; also called sticky rice, sweet rice or waxy rice) is a type of rice grown mainly in Southeast and East Asia, which has opaque grains, very low amylose content, and is especially sticky when cooked.
Copra meal
Copra meal is a byproduct of coconut oil extraction; once processed and pressed to extract the oil, the remaining compressed material can be pelletized and used as animal feed
Cottonseed (delinted)
Whole cotton seeds, delinted
Cottonseed meal
Cottonseed meal is the byproduct remaining after cotton is ginned and the seeds crushed and the oil extracted. The remaining meal is usually used for animal feed and in organic fertilizers.
Whole oats
Peanut hull, peanut seed, and whole peanut
Hulls of peanuts without seed material, seeds of peanuts without hulls, or entire peanuts
Whole rye
Whole sorghum, also called milo
Soybean meal
Byproduct after soybean oil is removed from soybeans, whether mechanical or solvent extraction; after removal of oil the remaining material is dried, toasted, and ground