Modified starch, also called starch derivatives, is prepared by physically,

enzymatically An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as produc ...

, or chemically treating native

starch Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diet ...

to change its properties. Modified starches are used in practically all starch applications, such as in food products as a

thickening agent A thickening agent or thickener is a substance which can increase the viscosity of a liquid without substantially changing its other properties. Edible thickeners are commonly used to thicken sauces, soups, and puddings without altering their ...

, stabilizer or

emulsifier An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Althou ...

; in

pharmaceutical Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the ...

s as a disintegrant; or as binder in

coated paper Coated paper (also known as enamel paper, gloss paper, and thin paper) is paper that has been coated with a mixture of materials or a polymer to impart certain qualities to the paper, including weight, surface gloss, smoothness, or reduced ink ab ...

. They are also used in many other applications. Starches are modified to enhance their performance in different applications. Starches may be modified to increase their stability against excessive heat, acid, shear, time, cooling, or freezing, to change their

texture Texture may refer to: Science and technology * Image texture, the spatial arrangement of color or intensities in an image * Surface texture, the smoothness, roughness, or bumpiness of the surface of an object * Texture (roads), road surface c ...

, to decrease or increase their

viscosity Viscosity is a measure of a fluid's rate-dependent drag (physics), resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for e ...

, to lengthen or shorten gelatinization time or to increase their visco-stability.

Modification methods

An ancient way of modifying starch is

malting Malting is the process of steeping, germinating, and drying grain to convert it into malt. Germination and sprouting involve a number of enzymes to produce the changes from seed to seedling and the malt producer stops this stage of the process w ...

grain, which humans have done for thousands of years. The plant's own

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

s modify the grain's starches. The effects can be modulated by varying the duration and the ambient conditions of the process. However, malting alone is not a limitless or optimized tool for every desirable end product. In recent centuries, humans have expanded their repertoire of starch-modifying methods by learning how to use simple substances such as

acid An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...

alkali In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The a ...

s, and

s from nature to modify starches in tailored ways. Acid-treated starch ( INS 1401), also called thin boiling starch, is prepared by treating

or starch granules with

inorganic acid A mineral acid (or inorganic acid) is an acid derived from one or more inorganic compounds, as opposed to organic acids which are acidic, organic compounds. All mineral acids form hydrogen ions and the conjugate base when dissolved in water. Ch ...

s, e.g.

hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ...

(equivalent to

stomach acid Gastric acid or stomach acid is the acidic component – hydrochloric acid – of gastric juice, produced by parietal cells in the gastric glands of the stomach lining. In humans, the pH is between one and three, much lower than most other an ...

), breaking down the starch molecule and thus reducing the viscosity. Other treatments producing modified starch (with different INS and E-numbers) are: *

dextrin Dextrins are a group of low-molecular-weight carbohydrates produced by the hydrolysis of starch and glycogen. Dextrins are mixtures of polymers of D-glucose units linked by α-(1→4) or α-(1→6) glycosidic bonds. Dextrins can be produced fro ...

(INS 1400), roasted starch with

* alkaline-modified starch (INS 1402) with

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula . It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly corrosive base (chemistry), ...

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which utili ...

* bleached starch (INS 1403) with

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usua ...

* oxidized starch (INS 1404, E1404) with

sodium hypochlorite Sodium hypochlorite is an alkaline inorganic chemical compound with the formula (also written as NaClO). It is commonly known in a dilute aqueous solution as bleach or chlorine bleach. It is the sodium salt of hypochlorous acid, consisting of ...

, breaking down viscosity * enzyme-treated starch (INS 1405),

maltodextrin Maltodextrin is a name shared by two different families of chemicals. Both families are glucose polymers (also called ''dextrose polymers'' or ''Dextrin, dextrins''), but have little chemical or nutritional similarity. The digestible maltodextr ...

cyclodextrin Cyclodextrins are a family of cyclic oligosaccharides, consisting of a macrocycle, macrocyclic ring of glucose subunits joined by α-1,4 glycosidic bonds. Cyclodextrins are produced from starch by enzyme, enzymatic conversion. They are used in ...

* monostarch phosphate (INS 1410, E1410) with

phosphorous acid Phosphorous acid (or phosphonic acid) is the Compound (chemistry), compound described by the chemical formula, formula . It is diprotic (readily ionizes two protons), not triprotic as might be suggested by its formula. Phosphorous acid is an in ...

or the salts

sodium phosphate A sodium phosphate is a generic variety of salts of sodium () and phosphate (). Phosphate also forms families or condensed anions including di-, tri-, tetra-, and polyphosphates. Most of these salts are known in both anhydrous (water-free) and ...

, potassium phosphate, or

sodium triphosphate Sodium triphosphate (STP), also sodium tripolyphosphate (STPP), or tripolyphosphate (TPP),

to reduce

retrogradation Retrogradation is the landward change in position of the front of a river delta with time. This occurs when the mass balance of sediment into the delta is such that the volume of incoming sediment is less than the volume of the delta that is los ...

* distarch phosphate (INS 1412, E1412) by esterification with for example

sodium trimetaphosphate Sodium trimetaphosphate (also STMP), with formula Na3P3O9, is one of the metaphosphates of sodium. It has the formula but the hexahydrate is also well known. It is the sodium salt of trimetaphosphoric acid. It is a colourless solid that finds s ...

crosslinked In chemistry and biology, a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds and the polymers can be either synthetic polymers or natural ...

starch modifying the

rheology Rheology (; ) is the study of the flow of matter, primarily in a fluid (liquid or gas) state but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applie ...

, the texture * acetylated starch (INS 1420, E1420)

esterification In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...

with

acetic anhydride Acetic anhydride, or ethanoic anhydride, is the chemical compound with the chemical formula, formula . Commonly abbreviated , it is one the simplest organic acid anhydride, anhydrides of a carboxylic acid and is widely used in the production of c ...

* hydroxypropylated starch (INS 1440, E1440), starch

ether In organic chemistry, ethers are a class of compounds that contain an ether group, a single oxygen atom bonded to two separate carbon atoms, each part of an organyl group (e.g., alkyl or aryl). They have the general formula , where R and R� ...

, with

propylene oxide Propylene oxide is an epoxide with the molecular formula C3H6O. This colourless volatile liquid with an odour similar to ether, is produced on a large scale industrially. Its major application is its use for the production of polyether polyols f ...

, increasing viscosity stability * hydroxyethyl starch, with

ethylene oxide Ethylene oxide is an organic compound with the chemical formula, formula . It is a cyclic ether and the simplest epoxide: a three-membered ring (chemistry), ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless ...

* starch sodium octenyl succinate (OSA) starch (INS 1450, E1450) used as

adding

hydrophobicity In chemistry, hydrophobicity is the chemical property of a molecule (called a hydrophobe) that is seemingly intermolecular force, repelled from a mass of water. In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to b ...

* starch aluminium octenyl Succinate (INS 1452, E1452) * cationic starch, adding positive

electrical charge Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwel ...

to starch * carboxymethylated starch with monochloroacetic acid adding negative charge and combined modifications such as * phosphated distarch phosphate (INS 1413, E1413) * acetylated distarch phosphate (INS 1414, E1414) * acetylated distarch adipate (INS 1422, E1422), * hydroxypropyl distarch phosphate (INS 1442, E1442), * acetylated oxidized starch (INS 1451, E1451). Modified starch may also be a cold-water-soluble, pregelatinized or instant starch which thickens and gels without heat, or a cook-up starch which must be cooked like regular starch. Drying methods to make starches cold-water-soluble are

extrusion Extrusion is a process used to create objects of a fixed cross section (geometry), cross-sectional profile by pushing material through a Die (manufacturing), die of the desired cross-section. Its two main advantages over other manufacturing pro ...

drum drying Drum drying is a method used for drying out liquids from raw materials with a drying drum. In the drum-drying process, pureed raw ingredients are dried at relatively low temperatures over rotating, high-capacity drums that produce sheets of drum-dr ...

spray drying Spray drying is a method of forming a dry powder from a liquid or slurry by rapidly drying with a hot gas. This is the preferred method of drying of many thermally-sensitive materials such as foods and pharmaceuticals, or materials which may requ ...

ization. Other starch derivatives, the starch sugars, like

glucose Glucose is a sugar with the Chemical formula#Molecular formula, molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae d ...

, high fructose syrup,

glucose syrup Glucose syrup, also known as confectioner's glucose, is a syrup made from the hydrolysis of starch. Glucose is a sugar. Maize (corn) is commonly used as the source of the starch in the US, in which case the syrup is called "corn syrup", but gluco ...

s, starch degraded with

amylase An amylase () is an enzyme that catalysis, catalyses the hydrolysis of starch (Latin ') into sugars. Amylase is present in the saliva of humans and some other mammals, where it begins the chemical process of digestion. Foods that contain large ...

are mainly sold as liquid

syrup In cooking, syrup (less commonly sirup; from ; , beverage, wine and ) is a condiment that is a thick, viscous liquid consisting primarily of a Solution (chemistry), solution of sugar in water, containing a large amount of dissolved sugars but ...

to make a

sweetener A sweetener is a substance added to food or drink to impart the flavor of sweetness, either because it contains a type of sugar, or because it contains a sweet-tasting sugar substitute. Various natural non-sugar sweeteners (NSS) and artificial s ...

Examples of use and functionality of modified starch

Pre-gelatinized starch is used to thicken instant

dessert Dessert is a course (food), course that concludes a meal; the course consists of sweet foods, such as cake, biscuit, ice cream, and possibly a beverage, such as dessert wine or liqueur. Some cultures sweeten foods that are more commonly umami, ...

s, allowing the food to thicken with the addition of cold water or milk. Similarly, cheese sauce granules such as in

Macaroni and Cheese Macaroni and cheese (colloquially known as mac and cheese and known as macaroni cheese in the United Kingdom) is a pasta dish of macaroni covered in cheese sauce, most commonly cheddar sauce. Its origins trace back to cheese and pasta casserol ...

lasagna Lasagna (, ; ), also known by the plural form lasagne (), is a type of pasta Pasta (, ; ) is a type of food typically made from an Leavening agent, unleavened dough of wheat flour mixed with water or Eggs as food, eggs, and formed in ...

, or

gravy Gravy is a sauce made from the juices of meats and vegetables that run naturally during cooking and often thickened with thickeners for added texture. The gravy may be further coloured and flavoured with gravy salt (a mix of salt and caramel food ...

granules may be thickened with boiling water without the product going lumpy. Commercial pizza toppings containing modified starch will thicken when heated in the oven, keeping them on top of the pizza, and then become runny when cooled. A suitably modified starch is used as a

fat substitute A fat substitute is a food product with the same functions, stability, physical, and chemical characteristics as regular fat, with fewer calories per gram than fat. They are utilized in the production of low fat and low calorie foods. Background Fa ...

for low-fat versions of traditionally fatty foods, e.g. industrial milk-based desserts like

yogurt Yogurt (; , from , ; also spelled yoghurt, yogourt or yoghourt) is a food produced by bacterial Fermentation (food), fermentation of milk. Fermentation of sugars in the milk by these bacteria produces lactic acid, which acts on milk protein to ...

or reduced-fat hard

salami Salami ( ; : ''salame'') is a ''salume'' consisting of fermented and air-dried meat, typically pork. Historically, salami was popular among Southern, Eastern, and Central European peasants because it can be stored at room temperature fo ...

having about 1/3 the usual fat content. For the latter type of uses, it is an alternative to the product

Olestra Olestra (also known by its brand name Olean) is a fat substitute food additive that adds no metabolizable calories to products. It has been used in the preparation of otherwise high-fat foods, thereby lowering or eliminating their fat content. ...

. Modified starch is added to frozen products to prevent them from dripping when defrosted. Modified starch, bonded with

phosphate Phosphates are the naturally occurring form of the element phosphorus. In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthop ...

, allows the starch to absorb more water and keeps the ingredients together. Modified starch acts as an emulsifier for

French dressing French dressing is a creamy dressing in American cuisine based upon oil, vinegar, tomato, sugar, and other often finely chopped ingredients. Its composition was once regulated by the United States federal government, which withdrew its standard ...

by enveloping oil droplets and suspending them in the water. Acid-treated starch forms the shell of jelly beans. Oxidized starch increases the stickiness of batter. Carboxymethylated starches are used as a

wallpaper adhesive Adhesive flakes that are mixed with water to produce wallpaper paste Wallpaper adhesive or wallpaper paste is a specific adhesive, based on modified starch, methylcellulose, or clay which is used to fix wallpaper to walls. Wallpaper pastes have ...

, as

textile printing Textile printing is the process of applying Color of clothing, color to textile, fabric in definite patterns or designs. In properly printing, printed fabrics the colour is bonded with the fiber, fibre, so as to resist washing and friction. ...

thickener, as tablet disintegrants and

excipients An excipient is a substance formulated alongside the active ingredient of a medication. They may be used to enhance the active ingredient’s therapeutic properties; to facilitate drug absorption; to reduce viscosity; to enhance solubility; to i ...

in the pharmaceutical industry.

Cation An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

ic starch is used as wet end

sizing Sizing or size is a substance that is applied to, or incorporated into, other materials—especially papers and textiles—to act as a protective filler or glaze. Sizing is used in papermaking and textile manufacturing to change the absorption ...

agent in

paper manufacturing A paper mill is a factory devoted to making paper from vegetable fibres such as wood pulp, old rags, and other ingredients. Prior to the invention and adoption of the Fourdrinier machine and other types of paper machine that use an endless belt ...

Genetically modified starch

Modified starch should not be confused with genetically modified starch, which refers to starch from genetically engineered plants, such as those that have been genetically modified to produce novel fatty acids or carbohydrates which might not occur in the plant species being harvested. In Europe the term "

Genetically Modified Organism A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. The exact definition of a genetically modified organism and what constitutes genetic engineering varies, with ...

" is used solely where "the genetic material has been altered in a way that does not occur naturally through fertilisation and/or natural recombination". The modification in "genetically modified" refers to the genetic engineering of the plant

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

, whereas in the term "Modified Starch" seen on

mandatory Mandate most often refers to: * League of Nations mandates, quasi-colonial territories established under Article 22 of the Covenant of the League of Nations, 28 June 1919 * Mandate (politics), the power granted by an electorate Mandate may also r ...

ingredient In a general sense, an ingredient is a substance which forms part of a mixture. In cooking, recipes specify which ingredients are used to prepare a dish, and the term may also refer to a specific food item in relation to its use in different re ...

labels A label (as distinct from signage) is a piece of paper, plastic film, cloth, metal, or other material affixed to a container or product. Labels are most often affixed to packaging and containers using an adhesive, or sewing when affixed to ...

it refers to the later processing or treatment of the starch or starch granules. Genetically modified starch is of interest in the manufacture of biodegradable polymers and noncellulose feedstock in the

paper industry The pulp and paper industry comprises companies that use wood, specifically pulpwood, as raw material and produce pulp, paper, paperboard, and other cellulose-based products. Manufacturing process In the manufacturing process, pulp is intro ...

, as well as the creation of new

food additives Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives, such as vinegar ( pickling), salt ( salting), smoke (smoking) and sugar (crystallization), have been used for ...

. For example, researchers aim to alter the enzymes within living plants to create starches with desirable modified properties, and thus eliminate the need for enzymatic processing after starch is extracted from the plant.

Modification methods

Examples of use and functionality of modified starch

Genetically modified starch

See also

References

Suggested reading