Dry matter
Encyclopedia
The dry matter is a measurement of the mass of something when completely dried.
The dry matter of plant and animal material would be its solids, i.e. all its constituents excluding water. The dry matter of food would include carbohydrate
s, fat
s, protein
s, vitamin
s, minerals
, and antioxidant
s (e.g., thiocyanate
, anthocyanin
, and quercetin
). Carbohydrates, fats, and proteins, which provide the energy in foods (measured in kilocalories or kilojoules), make up ninety percent of the dry weight of a diet. Water content in foods varies widely. A large number of foods are more than half water by weight, including boiled oatmeal (84.5%), cooked macaroni (78.4%), boiled eggs (73.2%), boiled rice (72.5%), white meat chicken (70.3%) and sirloin steak (61.9%). Fruits and vegetables are 70 to 95% water. Most meats are on average about 70% water. Breads are approximately 36% water. Some foods have a water content of less than 5%, e.g., peanut butter, crackers, and chocolate cake.
Water content of dairy products is quite variable. Butter is 15% water. Cow's milk ranges between 88-86% water. Swiss cheese is 37% percent water. The water content of milk and dairy products varies with the percentage of butterfat
so that whole milk has the lowest percentage of water and skimmed milk has the highest. Dry matter in cheese contains proteins, butterfat, lactose
(milk sugar, although in very small quantities due to lactose fermentation during cheese makinghttp://www.milk.co.uk/page.aspx?intPageID=195), and minerals. To determine a cheese's fat content, one analyses its dry matter to obtain the fat in dry matter (abbreviated FDM or FiDM) proportion, and then takes into account the water present in the cheese. For example, if a cheese were 50% water and 25% fat, there would be 50% fat in dry matter.
In the sugar industry the dry matter content is an important parameter to control the crystallization process and is often measured on-line by means of microwave density meters.
Dry matter can refer to the dry portion of animal feed. A substance in the feed, such as a nutrient or toxin, can be referred to on a dry matter basis to show its level in the feed (e.g., ppm
). Considering nutrient levels in different feeds on a dry matter basis (rather than an as-is basis) makes a comparison easier because feeds contain different percentages of water. This also allows a comparison between the level of a given nutrient in dry matter and the level needed in an animal’s diet. Dry matter intake (DMI) refers to feed intake excluding its water content. The percentage of water is frequently determined by heating the feed on a paper plate in a microwave oven or using the Koster Tester to dry the feed. Ascertaining DMI can be useful for low-energy feeds with a high percentage of water in order to ensure adequate energy intake. Animals eating these kinds of feeds have been shown to consume less dry matter and food energy. A problem called dry matter loss can result from heat generation, as caused by microbial respiration. It decreases the content of nonstructural carbohydrate, protein, and food energy.
The dry matter of plant and animal material would be its solids, i.e. all its constituents excluding water. The dry matter of food would include carbohydrate
Carbohydrate
A carbohydrate is an organic compound with the empirical formula ; that is, consists only of carbon, hydrogen, and oxygen, with a hydrogen:oxygen atom ratio of 2:1 . However, there are exceptions to this. One common example would be deoxyribose, a component of DNA, which has the empirical...
s, fat
Fat
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure...
s, protein
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
s, vitamin
Vitamin
A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. In other words, an organic chemical compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on...
s, minerals
Dietary mineral
Dietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen present in common organic molecules. Examples of mineral elements include calcium, magnesium, potassium, sodium, zinc, and iodine...
, and antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
s (e.g., thiocyanate
Thiocyanate
Thiocyanate is the anion [SCN]−. It is the conjugate base of thiocyanic acid. Common derivatives include the colourless salts potassium thiocyanate and sodium thiocyanate. Organic compounds containing the functional group SCN are also called thiocyanates...
, anthocyanin
Anthocyanin
Anthocyanins are water-soluble vacuolar pigments that may appear red, purple, or blue according to pH...
, and quercetin
Quercetin
Quercetin , a flavonol, is a plant-derived flavonoid found in fruits, vegetables, leaves and grains. It also may be used as an ingredient in supplements, beverages or foods.-Occurrence:...
). Carbohydrates, fats, and proteins, which provide the energy in foods (measured in kilocalories or kilojoules), make up ninety percent of the dry weight of a diet. Water content in foods varies widely. A large number of foods are more than half water by weight, including boiled oatmeal (84.5%), cooked macaroni (78.4%), boiled eggs (73.2%), boiled rice (72.5%), white meat chicken (70.3%) and sirloin steak (61.9%). Fruits and vegetables are 70 to 95% water. Most meats are on average about 70% water. Breads are approximately 36% water. Some foods have a water content of less than 5%, e.g., peanut butter, crackers, and chocolate cake.
Water content of dairy products is quite variable. Butter is 15% water. Cow's milk ranges between 88-86% water. Swiss cheese is 37% percent water. The water content of milk and dairy products varies with the percentage of butterfat
Butterfat
Butterfat or milkfat is the fatty portion of milk. Milk and cream are often sold according to the amount of butterfat they contain.- Composition :The fatty acids of butterfat are typically composed as follows :...
so that whole milk has the lowest percentage of water and skimmed milk has the highest. Dry matter in cheese contains proteins, butterfat, lactose
Lactose
Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2~8% of milk , although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from or , the Latin word for milk,...
(milk sugar, although in very small quantities due to lactose fermentation during cheese makinghttp://www.milk.co.uk/page.aspx?intPageID=195), and minerals. To determine a cheese's fat content, one analyses its dry matter to obtain the fat in dry matter (abbreviated FDM or FiDM) proportion, and then takes into account the water present in the cheese. For example, if a cheese were 50% water and 25% fat, there would be 50% fat in dry matter.
In the sugar industry the dry matter content is an important parameter to control the crystallization process and is often measured on-line by means of microwave density meters.
Dry matter can refer to the dry portion of animal feed. A substance in the feed, such as a nutrient or toxin, can be referred to on a dry matter basis to show its level in the feed (e.g., ppm
Parts-per notation
In science and engineering, the parts-per notation is a set of pseudo units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they are pure numbers with no associated units of measurement...
). Considering nutrient levels in different feeds on a dry matter basis (rather than an as-is basis) makes a comparison easier because feeds contain different percentages of water. This also allows a comparison between the level of a given nutrient in dry matter and the level needed in an animal’s diet. Dry matter intake (DMI) refers to feed intake excluding its water content. The percentage of water is frequently determined by heating the feed on a paper plate in a microwave oven or using the Koster Tester to dry the feed. Ascertaining DMI can be useful for low-energy feeds with a high percentage of water in order to ensure adequate energy intake. Animals eating these kinds of feeds have been shown to consume less dry matter and food energy. A problem called dry matter loss can result from heat generation, as caused by microbial respiration. It decreases the content of nonstructural carbohydrate, protein, and food energy.