Homogenization (chemistry)

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Homogenizing valve, a method to homogenize at high pressure Homogenizing valve.svg
Homogenizing valve, a method to homogenize at high pressure

Homogenization or homogenisation is any of several processes used to make a mixture of two mutually non-soluble liquids the same throughout. [2] This is achieved by turning one of the liquids into a state consisting of extremely small particles distributed uniformly throughout the other liquid. A typical example is the homogenization of milk, wherein the milk fat globules are reduced in size and dispersed [3] uniformly through the rest of the milk. [4]

Contents

Definition

Homogenization (from "homogeneous;" Greek, homogenes: homos, same + genos, kind) [5] is the process of converting two immiscible liquids (i.e. liquids that are not soluble, in all proportions, one in another) into an emulsion [6] (Mixture of two or more liquids that are generally immiscible). Sometimes two types of homogenization are distinguished: primary homogenization, when the emulsion is created directly from separate liquids; and secondary homogenization, when the emulsion is created by the reduction in size of droplets in an existing emulsion. [6] Homogenization is achieved by a mechanical device called a homogenizer. [6]

Application

One of the oldest applications of homogenization is in milk processing. [7] It is normally preceded by "standardization" (the mixing of milk from several different herds or dairies to produce a more consistent raw milk prior to processing). [7] The fat in milk normally separates from the water and collects at the top. Homogenization breaks the fat into smaller sizes so it no longer separates, allowing the sale of non-separating milk at any fat specification. [3]

Methods

Milk homogenization is accomplished by mixing large amounts of harvested milk, then forcing the milk at high pressure through small holes. [7] Milk homogenization is an essential tool of the milk food industry to prevent creating various levels of flavor and fat concentration.

Another application of homogenization is in soft drinks like cola products. The reactant mixture is rendered to intense homogenization, to as much as 35,000 psi, [8] so that various constituents do not separate out during storage or distribution. [9]

See also

Related Research Articles

An emulsion is a mixture of two or more liquids that are normally immiscible owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid is dispersed in the other. Examples of emulsions include vinaigrettes, homogenized milk, liquid biomolecular condensates, and some cutting fluids for metal working.

<span class="mw-page-title-main">Solution (chemistry)</span> Homogeneous mixture of a solute and a solvent

In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent. If the attractive forces between the solvent and solute particles are greater than the attractive forces holding the solute particles together, the solvent particles pull the solute particles apart and surround them. These surrounded solute particles then move away from the solid solute and out into the solution. The mixing process of a solution happens at a scale where the effects of chemical polarity are involved, resulting in interactions that are specific to solvation. The solution usually has the state of the solvent when the solvent is the larger fraction of the mixture, as is commonly the case. One important parameter of a solution is the concentration, which is a measure of the amount of solute in a given amount of solution or solvent. The term "aqueous solution" is used when one of the solvents is water.

<span class="mw-page-title-main">Margarine</span> Semi-solid oily spread often used as a butter substitute

Margarine is a spread used for flavoring, baking, and cooking. It is most often used as a substitute for butter. Although originally made from animal fats, most margarine consumed today is made from vegetable oil. The spread was originally named oleomargarine from Latin for oleum and Greek margarite. The name was later shortened to margarine.

<span class="mw-page-title-main">Whey</span> Liquid remaining after milk has been curdled and strained

Whey is the liquid remaining after milk has been curdled and strained. It is a byproduct of the manufacturing of cheese or casein and has several commercial uses. Sweet whey is a byproduct resulting from the manufacture of rennet types of hard cheese, like cheddar or Swiss cheese. Acid whey is a byproduct brought out during the making of acid types of dairy products, such as strained yogurt.

<span class="mw-page-title-main">Ultra-high-temperature processing</span> Food sterilization process

Ultra-high temperature processing (UHT), ultra-heat treatment, and ultra-pasteurization is a food processing technology that sterilizes a liquid food by heating the food for two to five seconds to a temperature greater than 140 °C (284 °F) to kill bacterial endospores. In the production of food products, UHT processing is applied to milk and milk products, and to the production of fruit juices, soy milk, wine, savoury canned foods, and honey. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s. The heat used during the UHT process can cause Maillard browning and change the taste and smell of dairy products. An alternative process is flash pasteurization, in which the milk is heated to 72 °C (162 °F) for at least fifteen seconds.

<span class="mw-page-title-main">Buttermilk</span> Fermented dairy drink

Buttermilk is a fermented dairy drink. Traditionally, it was the liquid left behind after churning butter out of cultured cream. As most modern butter in western countries is not made with cultured cream but uncultured sweet cream, most modern buttermilk in western countries is cultured separately. It is common in warm climates where unrefrigerated milk sours quickly.

<span class="mw-page-title-main">Lecithin</span> Generic term for amphiphilic substances of plant and animal origin

Lecithin is a generic term to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues which are amphiphilic – they attract both water and fatty substances, and are used for smoothing food textures, emulsifying, homogenizing liquid mixtures, and repelling sticking materials.

<span class="mw-page-title-main">Palmitic acid</span> Chemical compound

Palmitic acid is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms. Its chemical formula is CH3(CH2)14COOH, and its C:D is 16:0. It is a major component of the oil from the fruit of oil palms, making up to 44% of total fats. Meats, cheeses, butter, and other dairy products also contain palmitic acid, amounting to 50–60% of total fats. Palmitates are the salts and esters of palmitic acid. The palmitate anion is the observed form of palmitic acid at physiologic pH (7.4). Major sources of C16:0 are palm oil, palm kernel oil, coconut oil, and milk fat.

<span class="mw-page-title-main">Coconut milk</span> Liquid made from grated coconut meat

Coconut milk is an opaque, milky-white liquid extracted from the grated pulp of mature coconuts. The opacity and rich taste of coconut milk are due to its high oil content, most of which is saturated fat. Coconut milk is a traditional food ingredient used in Southeast Asia, Oceania, South Asia, and East Africa. It is also used for cooking in the Caribbean, tropical Latin America, and West Africa, where coconuts were introduced during the colonial era.

<span class="mw-page-title-main">Therapeutic food</span> Foods designed for specific therapeutic purposes

Therapeutic foods are foods designed for specific, usually nutritional, therapeutic purposes as a form of dietary supplement. The primary examples of therapeutic foods are used for emergency feeding of malnourished children or to supplement the diets of persons with special nutrition requirements, such as the elderly.

<span class="mw-page-title-main">Whey protein</span> Protein supplement

Whey protein is a mixture of proteins isolated from whey, the liquid material created as a by-product of cheese production. The proteins consist of α-lactalbumin, β-lactoglobulin, serum albumin and immunoglobulins. Glycomacropeptide also makes up the third largest component but is not a protein. Whey protein is commonly marketed as a protein supplement, and various health claims have been attributed to it. A review published in 2010 in the European Food Safety Authority Journal concluded that the provided literature did not adequately support the proposed claims.

<span class="mw-page-title-main">Separatory funnel</span> Laboratory glassware

A separatory funnel, also known as a separation funnel, separating funnel, or colloquially sep funnel, is a piece of laboratory glassware used in liquid-liquid extractions to separate (partition) the components of a mixture into two immiscible solvent phases of different densities. Typically, one of the phases will be aqueous, and the other a lipophilic organic solvent such as ether, MTBE, dichloromethane, chloroform, or ethyl acetate. All of these solvents form a clear delineation between the two liquids. The more dense liquid, typically the aqueous phase unless the organic phase is halogenated, sinks to the bottom of the funnel and can be drained out through a valve away from the less dense liquid, which remains in the separatory funnel.

<span class="mw-page-title-main">Calcium caseinate</span> Chemical compound

Calcium caseinate is one of several milk proteins derived from casein in skim and 1% milk. Calcium caseinate has a papery, sweet and overall bland flavor, and is primarily used in meal preparation and fat breakdown. Caseinates are produced by adding an alkali to another derivative of casein, acid casein. The type of caseinate is determined by the cation added alongside the acid casein. Other cations used to form caseinates besides calcium include ammonium, potassium, and sodium.

A dispersion is a system in which distributed particles of one material are dispersed in a continuous phase of another material. The two phases may be in the same or different states of matter.

<span class="mw-page-title-main">Oat milk</span> Type of plant milk made from oats

Oat milk is a plant milk derived from whole oat grains by extracting the plant material with water. Oat milk has a creamy texture and mild oatmeal-like flavor, and is manufactured in various flavors, such as sweetened, unsweetened, vanilla, and chocolate.

<span class="mw-page-title-main">Miniemulsion</span> Particular type of emulsion

A miniemulsion is a particular type of emulsion. A miniemulsion is obtained by shearing a mixture comprising two immiscible liquid phases, one or more surfactants and, possibly, one or more co-surfactants. They usually have nanodroplets with uniform size distribution (20–500 nm) and are also known as sub-micron, mini-, and ultra-fine grain emulsions.

<span class="mw-page-title-main">Miscibility</span> Ability of two substances to form a homogeneous solution when mixed regardless of concentration

Miscibility is the property of two substances to mix in all proportions, forming a homogeneous mixture. The term is most often applied to liquids but also applies to solids and gases. An example in liquids is the miscibility of water and ethanol as they mix in all proportions.

<span class="mw-page-title-main">Fat content of milk</span> Butterfat proportion of milk, by weight

The fat content of milk is the proportion of milk, by weight, made up by butterfat. The fat content, particularly of cow's milk, is modified to make a variety of products. The fat content of milk is usually stated on the container, and the color of the label or milk bottle top varied to enable quick recognition.

Milk protein concentrate (MPC) is any type of concentrated milk product that contains 40–90% milk protein. The United States officially defines MPC as "any complete milk protein concentrate that is 40 percent or more protein by weight." In addition to ultrafiltered milk products, the MPC classification includes concentrates made through other processes, such as blending nonfat dry milk with highly concentrated proteins, such as casein.

<span class="mw-page-title-main">Sour cream</span> Fermented dairy product

Sour cream is a dairy product obtained by fermenting regular cream with certain kinds of lactic acid bacteria. The bacterial culture, which is introduced either deliberately or naturally, sours and thickens the cream. Its name comes from the production of lactic acid by bacterial fermentation, which is called souring. Crème fraîche is one type of sour cream with a high fat content and less sour taste.

References

  1. "The Effect of the Second-Stage Homogenizing Valve" (PDF) (Technical bulletin). SPXFLOW. September 2019. Retrieved 2024-02-01.
  2. Brakeman, Rob. "Homogenizing Process | Homogenization | Sonic Mixing Corp". Sonic Corporation. Retrieved 2024-02-01.
  3. 1 2 "Why Is Milk Homogenized and What Are its Effects? | Dairy Nutrition". dairynutrition.ca. 2021-08-06. Retrieved 2024-02-01.
  4. "Homogenization", Encyclopædia Britannica. Encyclopædia Britannica Online Academic Edition, Encyclopædia Britannica Inc. , retrieved October 6, 2013
  5. homo-, word origin
  6. 1 2 3 McClements, David J. (2008). "Lipid-Based Emulsions and Emulsifiers". In Akoh, Casimir C.; Min, David B. (eds.). Food Lipids: Chemistry, Nutrition, and Biotechnology. Food Science and Technology (Third ed.). Boca Raton, Florida: CRC. p. 77. ISBN   978-1420046649.
  7. 1 2 3 "Homogenization of Milk: What It Is and How to Process". Ginhong. 2022-09-03. Retrieved 2024-02-01.
  8. Ferragut, Victoria; Hernández-Herrero, Manuela; Veciana-Nogués, María Teresa; Borras-Suarez, Miquel; González-Linares, Javier; Vidal-Carou, María Carmen; Guamis, Buenaventura (2015-03-30). "Ultra-high-pressure homogenization (UHPH) system for producing high-quality vegetable-based beverages: physicochemical, microbiological, nutritional and toxicological characteristics: Soy and almond beverages produced by UHPH". Journal of the Science of Food and Agriculture. 95 (5): 953–961. doi:10.1002/jsfa.6769.
  9. Müller, U.; Rossmann, S.; Schneider, J.; Kohlus, R. "(231aj) Direct Homogenization of Beverage Emulsions with the Innovative Counterflow Injection Process | AIChE". www.aiche.org. Retrieved 2024-02-01.