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T 2,4,5-T Herbicide which has been used to control weeds among a range of fruits, vegetables and ce- reals. Also known as 2,4,5-trichlorophenoxyacetic acid. Listed by WHO as obsolete. Table grapes Species of grapes grown for eating as opposed to winemaking or drying. They are seeded or seedless fruits of the genus Vitis, the most impor- tant species of which is V. vinifera. While most grapes are grown as winemaking grapes, significant amounts are produced as table grapes. Table grapes have a firmer flesh and lower level of acidity than winemaking grapes. All grapes are rich in sugar, but contain little vitamin C. Organic acids include tar- taric acid and malic acid in approximately equal amounts. Black grapes contain anthocyanins. Table grapes are eaten out of hand, or used in salads, pies and other desserts. Table jellies Fruit flavoured sweetened desserts set with gelatin or similar gelling agents. Known as jello in the USA. Table olives Olives from suitable varieties of the olive tree which have been processed to make them edible. Debittering treatment is an important stage in table olive production because the presence of the bit- ter glycoside oleuropein in raw olives renders them unpalatable. Processing may also be required for preservation purposes, enabling olives to be stored for long periods and consumed as required. Processing methods include fermentation and/or curing in oils, water, brines or salt. Olives may also be fla- voured by soaking in marinades or by stuffing. Only the highest quality fruit are processed as table ol- ives, taking into account factors such as variety, size, ripeness and damage. Rejected fruit, e.g. small, mis- shapen or damaged olives, can be used for the produc- tion of olive oils. Green olives are harvested early in the ripening period and natural black olives are late harvested. Tacos Pancakes made from corn flour which are filled with meat mince, cheese or beans, together with piquant sauces, before being fried. Taco shells Crisp food products made from corn masa dough which are shaped into thin discs and formed into a U-shape before being fried. Often filled with cooked beef mince and sauces and topped with shredded lettuce and grated cheese. Taenia Genus of parasitic tapeworms of the class Cestoda. Taenia solium is associated with pork, while T. saginata is associated with beef. Infection in hu- mans is usually transmitted by eating raw or under- cooked beef or pork. Tagatose Ketose monosaccharide comprising six carbon atoms (hexoses); an isomer of galactose. Has sweetness similar to that of sucrose but no calorific value, making it suitable as a low-calorie sweetener and bulking agent. Formed by bacterial fermentation using galactitol as substrate or pro- duced from lactose via isomerization of galac- tose. Tagliatelli Pasta formed into narrow flat ribbons. Tahini Paste made from ground sesame seeds. Used as an ingredient of humous and also as the base for sauces. Taints Sensory properties relating to the percep- tion of off flavour or off odour in a product. Taints in foods can be related to, for example, warmed over flavour in ready meals or boar taint in pork products. Take away foods Cooked dishes, often fast foods, which are sold at restaurants or other catering out- lets for consumption off the premises. Takju Rice wines manufactured in Korea. Talaromyces Genus of fungi of the family Tricho- comaceae. Anamorphs include Penicillium and Pae- cilomyces spp. Occur in soil and decaying plant ma- terial. Some species (e.g. Talaromyces flavus) may cause spoilage of fruits and fruit juices. A range of enzymes is produced by many species of this genus, e.g. T. stipitatu produces feruloyl esterases and xy- lan degrading enzymes, T. emersonii produces xy- lan-degrading enzymes, Į-glucuronidases and endo-1,3(4)-ȕ-glucanases, and T. thermophilus produces ȕ-galactosidases. Taleggio cheese Italian semi-soft cheese made from cow milk. Also known as Stracchino. Flavour is buttery and fruity. Rind is pinkish-grey and the inte- rior is white. Ripening lasts 25-50 days. Also pro- duced as a cooked curd variety that is firmer and simi- 416 Tallow Tape lar to mozzarella cheese. Taleggio is an excellent dessert cheese. Tallow Solid animal fats normally derived from cat- tle or sheep tissue, containing high levels of satu- rated fatty acids and monounsaturated fatty ac- ids (triglycerides of stearic acid, palmitic acid and oleic acid). White, flavourless, odourless and solid at room temperature. Usually prepared by heating suet under pressure in closed vessels. Used for frying and in shortenings. Tamales Concentric layered corn products, tradition- ally produced in Mexico. Some tamales include sea- soned meat, for example beef tamales, but others are prepared without meat, for example green tamales. Tamarillos Fruits produced by Cyphomandra beta- cea. Skin is yellow to deep red in colour, while the flesh varies from yellow-orange to purple. Contains numerous seeds. Rich in potassium and caro- tenes, with moderate amounts of vitamin E and vi- tamin C. Best eaten cooked, with the bitter tasting skin removed. Used in a range of products, including juices, sauces, chutneys and relishes. Also known as tree tomatoes. Tamarinds Common name for fruits of Tamarindus indica. The brown, curved pods contain a sticky pulp studded with up to 10 starchy seeds that can be eaten as a pulse. The sweet-sour flavoured pulp is extracted and used in a variety of foods, including sweet- meats, curries, preserves and chutneys. Leaves and flowers of the plant are also eaten in India. Tamper evident closures Closures designed to ensure that any unauthorized interference is evident. Tamper evident packaging Packaging designed to ensure that any unauthorized interference is evident. Tangelo Citrus fruits that are a cross between tan- gerines and pummelos. The most popular varieties are the minneola, with few seeds and a tart, sweet flavour, and the Orlando, a many-seeded fruit with a mild, sweet flavour. Tangerine juices Fruit juices extracted from tan- gerines (Citrus reticulata). Tangerines are processed into single strength juices and frozen concentrates. Of- ten blended with orange juices, as they contribute a deep orange colour. However, the amount added to blends is usually <10% as higher amounts can impart an off flavour to the orange juice products. Tangerines Small, loose-skinned citrus fruits (Cit- rus reticulata). Relatively good source of vitamin C. This species also includes mandarins and sat- sumas, names tending to be used indiscriminately. Tangerines tend to be darker in colour than mandar- ins. Consumed fresh or as a dessert, often as canned segments. Used in several citrus hybrids. Tangle Alternative term for brown seaweeds of the genus Laminaria. Tangor Citrus fruits that are a cross between tan- gerines and oranges. Similar in flavour to oranges, but contain many seeds. Tania Common name for Xanthosoma sagittifolium, the corm of which is processed in a similar way to taro. Nutritionally similar to taro also, although the starch is more difficult to digest. Sometimes used as the base for preparation of fufu. Also known as tannia, taniers, yautia or new cocoyams. Taniers Alternative term for tania. Tanks Large storage chambers or containers, par- ticularly for gases or liquids. In the dairy industry, bulk milk cooling tanks are used for cooling and holding raw milk after collection. Tannases EC 3.1.1.20. Esterases which catalyse the breakdown of hydrolysable tannins and gallic acid esters. Used in the manufacture of teas and other beverages, including wines and fruit juices. Also used to produce gallic acid and to remove unwanted tannins from foods and food processing wastes and effluents. Tannic acid Polyphenol which displays an- timutagenicity, anticarcinogenicity and antioxi- dative activity. Used as a food additive, a clarifying agent and a refining agent, but may inhibit the ab- sorption of dietary iron. Tannins Complex polyhydroxybenzoic acid deriva- tives found in many foods. Antinutritional factors inhibiting the bioavailability of vitamins and min- erals, and may be carcinogenic. However, also pos- sess antimicrobial activity, antioxidative activity and antitumour activity. Tanoor Thin Middle Eastern leavened flat bread made from high-extraction wheat flour. Tanshen Common name for Salina miltiorrhiza, the roots of which are used widely in Chinese herbal medicine. Extracts display antitumour activity, an- timutagenicity and antioxidative activity. Also known as dan shen. Tansy Common name for Tanacetum vulgare, the leaves and tops of which are used as herbs with a bit- ter flavour. Leaves are used in preparation of herb tea, salads and herb stuffings. Tansy essential oils and extracts contain significant amounts of the toxin Į- thujone. Only Į-thujone-free tansy oils are permitted as food additives and their use is limited to alcoholic beverages. Tape Indonesian alcoholic fermented foods made by inoculating steamed glutinous rice or mashed cas- sava with a combination of starters, and incubating in airtight containers. Tape (alternatively termed 417 Tape ketan Taste panels tapai) made with glutinous rice is called tape ketan, and that made with mashed cassava is called tape ketela. Products have spongy texture and mild, sweet, wine-like aroma and flavour. Eaten as snack foods. Tape ketan Indonesian alcoholic fermented foods (general name tape) made by inoculating steamed glu- tinous rice with a combination of starters, and incu- bating in airtight containers. Eaten as snack foods. Tape ketela Indonesian alcoholic fermented foods (general name tape) made by inoculating mashed cassava (also known as peuyeum) with a combina- tion of starters, and incubating in airtight contain- ers. Eaten as snack foods. Tapeworms Parasitic worms of the class Cestoda. As adults they live in the intestines of vertebrates and as juveniles they often live in the bodies of various ani- mals. Species infecting man include Hymenolepis nana, Taenia solium (particularly from pork), Taenia saginata (particularly from beef) and Diphyllo- bothrium latum (from raw fish). Tapeworm infection can be asymptomatic, or may generate symptoms in- cluding increased appetite, weight loss, diarrhoea, constipation and abdominal discomfort. Cysticerco- sis, a complication of Taenia solium infection, may occur when larvae develop outside of the intestinal tract. Tapioca Starch extracted from tubers of cassava (Manihot esculenta). Also called cassava starch . Tapioca starch Alternative term for tapioca. Tap water Water supplied to consumers via the water mains system; usually suitable for use as drinking water. Tarag Asian fermented milk of a variety of species. Tara gums Gums obtained from seeds of the tara tree (Caesalpinia spinosa) by grinding of the en- dosperm. Composed mainly of galactomannans, on average there are 3 mannose residues to every 1 ga- lactose residue. Used as stabilizers and thicken- ers. Tarama Fermented fish product containing fish roes (usually from carp) mixed with salt, breadcrumbs, Feta cheese, olive oils and lemon juices. Tarhana Traditional Turkish version of kishk, a fer- mented wheat flour-yoghurt mixture used in soups. The Greek version of kishk is known as trahanas. Taro Common name for Colocasia esculenta or C. antiquorum. The corm is eaten cooked; if not well enough cooked, irritation of the mouth results due to oxalate crystals. Used as a vegetable, in soups and stews, processed to make fufu or fermented to produce poi. Subsidiary corms (cormels), known as eddo in China and Japan, and leaves are also eaten. Taro is a good source of potassium and fibre. Leaves contain carotenes and are rich in vitamin C. Tarragon Common name for Artemisia dracunculus, the leaves of which have a sweet, mild anise-like fla- vour and are used as spices. The predominant fla- vour compound is estragole, also known as p- allylanisole and methyl chavicol. Tarragon is used in flavourings for foods such as meat and meat products, flavoured vinegar and pickles. Leaf es- sential oils are extracted and also used as flavour- ings. Also known as estragon. Tartaric acid Organic acid present in fruits and iso- lated from potassium tartrate films produced as a by- product in winemaking. Tartaric acid, as well as so- dium and calcium tartrates, have many uses as food additives, including as flavourings (acidulants) imparting a fruity flavour, humectants, antioxi- dants, sequestrants and as part of a pH buffering system. Tartaric acid is also a substrate for production of the raising agent, cream of tartar (potassium hydro- gen tartrate) which is an ingredient of baking pow- ders. Systematic name is 2,3-dihydroxybutanedioic acid. Tartrates Salts of tartaric acid. Crystallization of tartrates in wines is a problem, since the wines are then generally considered unacceptable by consumers. Tartrazine Synthetic bright yellow pyrazole dye used in artificial colorants for foods and beverages. In aqueous solution, tartrazine shows high stability when exposed to acids and alkalis, moderate stability to light and heat (stable at extrusion and baking tempera- tures) and poor stability in the presence of ascorbic acid. Synonymous with FD&C Yellow 5 and CI 19140. Tarts Open pastry cases made with shortcrust pastry, which are frequently baked blind (or empty) and then filled with sweet fillings such as fruits, jams or custards, or sometimes savoury mixtures, e.g. cheese or vegetables. Taste Sensation produced by stimulation of the taste buds on the tongue. The tongue can distinguish five separate tastes (sweet, salt, sour, bitter and sa- voury/umami). Often used as an alternative term for flavour. Taste panels Groups of individuals, untrained or trained, used to sample products and assess their fla- vour, with a view to providing an insight into con- sumer preferences. Taste panels are used in research, product development and for purposes of evaluating new and competitive products, and are not restricted to evaluating flavour. Texture, colour and many other quality factors can be measured meaningfully. 418 Taste thresholds Teleme cheese Taste thresholds Alternative term for flavour thresholds. Taurine Aminosulfonic acid synthesized from cys- teine and methionine. Abundant in animal pro- teins but is not found in vegetable proteins. Hence, vegetarians with insufficient cysteine and me- thionine intakes may have difficulty producing taurine. Taxonomy Study of the theory, practice and rules of classification and nomenclature of living and extinct organisms. The principles of taxonomy were estab- lished in the 18th century by the work of Linnaeus. As far as possible, organisms are arranged into a hierarchy of groups (called taxa) based on degrees of relationship (phylogeny). When knowledge of the evolution of a group is lacking, taxonomy is based on structural and other similarities. Under the Linnaean system, an or- ganism is classified according to a hierarchical system as follows: kingdom, phylum, class, order, family, ge- nus, species. TBA reactive substances Abbreviation for thiobar- bituric acid reactive substances (TBARS). Name ap- plied jointly to malonaldehyde and the other sub- stances formed during lipid oxidation, as measured in terms of thiobarbituric acid values (TBA values) determined from reaction with thiobarbituric acid (TBA). TBARS values are expressed as mg malonal- dehyde equivalents per kg of sample. Care must be taken when comparing TBARS values between differ- ent studies because of the many variations that have been developed for performing the TBA test. TBARS Abbreviation for TBA reactive sub- stances. TBA values Abbreviation for thiobarbituric acid values. TBHQ Abbreviation for tert-butylhydroquinone. TDE Persistent non-systemic organochlorine insecti- cide used to control a wide range of insects. Use on crops has generally been displaced by less persistent insecticides. Can occur as a degradation product of DDT. Classified by WHO as moderately hazardous (WHO II). Also known as DDD. Tea Hot or cold beverages made by infusion of dry, prepared leaves of Camellia sinensis in water. The main types are black tea, in manufacture of which the fresh tea leaves have undergone fermentation be- fore drying, and green tea, in which the fresh tea leaves have not undergone this fermentation. Oolong tea and pouchong tea have undergone partial fer- mentation, and are intermediate in character between green and black teas. Tea bags Tea packaged in small portion-size perme- able bags for easy preparation of tea beverages. Tea beverages Hot or cold beverages prepared from tea leaves or infusions. Tea granules Instant tea products comprising granules of dry tea extracts which are reconstituted into tea beverages on addition of water. Tea leaves Fresh or processed leaves of the tea plant, Camellia sinensis. Tea powders Instant tea products comprising pow- dered dry tea extracts which are reconstituted into tea beverages on addition of water. Teas Hot or cold beverages prepared by infusion of dry plant leaves, flowers or other plant parts. The type usually referred to as tea is made from the leaves of Camellia sinensis; other types include mate, rooibos tea, honeybush tea and a wide range of types of herb tea and fruit tea. Tea seed oils Vegetable oils extracted from the seeds of tea species such as Thea sasangua or Camel- lia oleifera. Used as salad oils and cooking oils. Tea tree oils Essential oils distilled from leaves of Melaleuca alternifolia, a tree native to Australia and certain parts of Asia. Major constituents of the oils are terpinen-4-ol, 1,8-cineole and Ȗ-terpinene. The oils have a warm, spicy flavour. Tea tree oils exhibit an- timicrobial activity and are used as an antiseptic. Although more commonly used for their therapeutic properties, tea tree oils are also used as food flavour- ings, including as a substitute for nutmeg. Tebuconazole One of the triazole fungicides. Also known as Folicur. A broad spectrum, systemic fungi- cide used as a seed treatment for control of fungal in- fections of barley, oats and wheat, for prevention of Fusarium head blight on wheat crops and as a foliar spray for preharvest treatment of fruits and vegeta- bles. Considered by the United States Food and Drug Administration to be safe, but listed as a potential car- cinogen in the United States Environmental Protection Agency Office of Pesticide Programs Carcinogen List. Classified by WHO as slightly hazardous (WHO III). Technetium Metallic element with the chemical sym- bol Tc. Tecto Alternative term for thiabendazole. Teff Tropical millet, Eragrostis abyssinica or E. tef, which is native to northeastern Africa and southeastern Arabia and is used as a cereal crop and livestock feed. Used to make the traditional flat bread, injera. Tehineh Pastes made from ground, dehulled, dry roasted sesame seeds. Teleme cheese Greek soft cheese prepared from ewe milk or cow milk. Now also made in California, USA. Similar to Brie cheese, with a tangy flavour that develops as the cheese ages. 419 Telemetry Teratogenicity Telemetry Process of transmitting readings from in- struments or measurements by radio or a telecommuni- cations link. TEM Abbreviation for transmission electron mi- croscopy. Temephos Non-systemic insecticide used primarily for control of mosquito and midge larvae and certain aquatic insects in urban and agricultural environ- ments. Also used for controlling lice on animals (in- cluding humans). Residues may contaminate water supplies. Classified by WHO as unlikely to present acute hazard in normal use. Also known as abate. Temik Alternative term for the insecticide aldicarb. Temp. abuse indicators Devices used to give an indication of whether products have been exposed to inappropriate temperatures that could cause damage during transport, distribution or storage. For example, indicators can be used to show whether frozen foods have been thawed during handling or storage; thaw- ing during distribution can potentially affect quality and safety. Indicator devices often produce a visible, irreversible colour change to show when temperature abuse has occurred. Microbial indicators may also be used to detect exposure to temperature abuse, espe- cially in animal carcasses. For example, poultry products that have been maintained at the correct tem- perature will have fairly constant counts of coliforms, while those that have been warmed will have higher counts. Tempe Alternative term for tempeh. Tempeh Product generally made by fermentation of soybeans, sometimes mixed with cereals. Used as meat extenders or meat substitutes. Cooked in a variety of ways or added to dishes such as sauces, soups and casseroles. Some types of tempeh are made from other materials, e.g. bongkrek is made by fermentation of presscake of coconuts or coconut milk residue. Temper Measure of the degree of crystallization of cocoa butter in chocolate and the type of crystals present. Temperature Degree or intensity of heat present in a substance or object or its surroundings, usually meas- ured using thermometers. Tempering Stabilization of chocolate by application of a melting and cooling process. Chocolate is tem- pered to stabilize the cocoa butter, a fat that can form crystals and cause bloom in the finished prod- uct. The classic tempering method includes the follow- ing stages: melting of the chocolate; working two- thirds of the melted chocolate on a marble slab with a metal spatula until it becomes thick; transferring the thickened chocolate back into the remaining melted chocolate; and reheating the product. Tempura Japanese dish prepared from vegetables, fish or shellfish, fried in batters. Tench Freshwater fish species (Tinca tinca) from the carp family (Cyprinidae); distributed across Europe and western Asia. Marketed fresh and frozen and as a canned product. Also known as lin. Tenderization Mechanical or chemical processes by which meat can be made easier to cut or chew, so im- proving its tenderness. Mechanical methods break down tough fibres in the meat, usually through pound- ing. Pounders can be made of metal or wood, and can be a variety of shapes and sizes. Chemical methods that can also be applied to soften meat fibres include application of long, slow cooking, marination in acidic marinades and use of commercial meat ten- derizers. Most meat tenderizers are composed primar- ily of papain, an enzyme extracted from papayas; they can also contain salt, sugar (usually glucose) and anticaking agents (usually calcium stearate). Tenderness Sensory properties related to the extent to which a product, such as meat, is tender, i.e. soft, palatable and chewable. Tenderness can be meas- ured using tenderometers. Tenderometers Instruments used to measure ten- derness or the stage of maturity of produce, particu- larly peas, on the basis of the force required to cause shearing. Tenjan Alternative term for doenjang. Tenox Registered trade name for a series of natural and synthetic antioxidants manufactured by Eastman Chemical. Tensile strength Measure of the resistance that a material produces to a pulling stress (tensile stress); measured in Newtons per square metre. Tensiometry Measurement of surface tension. Tenuazonic acid Mycotoxin produced mainly by Alternaria alternata growing on foods (e.g. fruits, vegetables and cereals). Tepary beans Seeds produced by Phaseolus acuti- folius, a plant that grows well under drought condi- tions. Vary greatly in shape and colour. Dried seeds are soaked before cooking or are ground into meal. Pinto beans may be substituted for tepary beans in recipes. Tequila Mexican spirits made by distillation of fermented sap of the agave plant. Teratogenesis Process leading to developmental abnormalities in the fetus. Teratogenicity Capacity of a substance to produce teratogenic effects, i.e. to cause developmental abnor- malities in the fetus. 420 Terbuthylazine Textured vegetable proteins Terbuthylazine Broad-spectrum triazine herbicide used for pre- or post-emergence control of weeds around a range of food plants. Classified by WHO as unlikely to present acute hazard in normal use. Terfezia Genus of edible fungi including desert truf- fles and the poor man's truffle. Termitomyces Genus of edible fungi. Terpenes Unsaturated hydrocarbons consisting of isoprene units found in many higher plants and es- sential oils. Typically, volatile compounds with pleasant odours used as flavourings. Terpenes are major components of citrus essential oils but, since they are not responsible for the characteristic flavour and readily oxidize and polymerize to produce un- pleasant flavours, they are generally removed by distil- lation or solvent extraction. Terpenoids Volatile compounds found in plants and essential oils which are important for flavour. Certain terpenoids exhibit antioxidative activity, anticarcinogenicity and antimutagenicity. Terpinene Flavour compounds found in plants and essential oils that have been found to inhibit food spoilage yeasts. Terpineol Monocyclic monoterpene alcohol used in flavourings. Found naturally in essential oils, citrus juices and wines, and can be produced by microbial transformation of limonene. Terpinyl acetate Flavour compound with antifungal activity that is found in essential oils. Terramycin Synonymous with oxytetracycline. Terrines Foods, particularly pates, which are cooked and served in earthenware tureens (or terrines). A pate made in this way is also referred to as pate en terrine. Terroir Total environment in which a grapevine is grown for the purpose of producing winemaking grapes. Includes a great many factors, including soil, climate, location and cultivation conditions. tert-Butylhydroquinone Commonly abbreviated to TBHQ . An antioxidant used in foods, including meat products, vegetable oils, potato crisps and ce- real products. Testosterone Male sex hormone produced by the interstitial cells of the testis of mammals. Used to pro- mote muscular development in certain animals. Tetilla cheese Spanish semi-soft cheese made from cow milk. Rind is pale yellow and ridged. The cheese has a fresh lemony flavour and a creamy consis- tency; fat content is 25%. Ripening is completed in 2-3 weeks. Tetrachlorodibenzo-p-dioxins Potent toxins re- leased into the environment from, for example, indus- trial sources that can then find their way as contami- nants into the food chain. Tetrachloroisophthalonitrile Alternative term for the fungicide chlorothalonil. Tetrachloromethane Synonym for carbon tetra- chloride. Organic halogen compound and versatile organic solvent whose use has diminished since the discovery that it is carcinogenic. May be used in fu- migants. Can occur as a contaminant of treated drinking water. Tetracyclines Broad-spectrum antibiotics widely used in animals both for prevention and treatment of disease, and as feed additives to promote growth. Dis- tribution is rapid and wide following administration, and residues may persist in some tissues. Tolerance values are specified for meat, livers, kidneys, animal fats, milk and eggs. Commonly used examples include chlortetracycline and oxytetracycline. Tetradifon Non-systemic contact acaricide used to control plant eating mites on a wide range of fruits and vegetables, hops and tea. Classified by WHO as unlikely to present acute hazard in normal use. Tetragenococcus Genus of lactic acid bacteria of the family Enterococcaceae. Includes the species Tet- ragenococcus halophilus, which is used in the fermen- tation of soy sauces and miso. Tetrahydrofolate Biochemically active form of folic acid. Coenzyme of various reactions involved in the metabolism of amino acids, purines and pyrimidines. Many foods are rich in folates, includ- ing green leafy vegetables, livers, fruits and yeast extracts. Tetrahydrophthalimide Primary degradation prod- uct of the fungicide captan. Tetrazoles Group of organic nitrogen com- pounds derived from tetrazole, a synthetic organic heterocyclic compound comprising four nitrogen at- oms and a single carbon atom. Dihydroxyphenoxy-1H- tetrazoles and their salts have been investigated as non- nutritive artificial sweeteners. Tetrodotoxin Highly toxic and potentially lethal neu- rotoxin found in many species of pufferfish. Pro- duced by bacteria which colonize the fish. Responsi- ble for poisoning caused by consumption of contami- nated pufferfish. Texture Sensory properties relating to the feel of a surface or product, or the impression created by a sur- face structure or the general physical appearance of a surface. A major factor affecting the mouthfeel and quality of a food. Textured vegetable proteins Plant protein products that are shaped and textured to form particles, or shaped pieces, such as chunks and strips, usually by spinning or extrusion technology. Typically formu- lated with added colorants and flavourings, and 421 Texture profile analysis Thermal stability used as meat substitutes. Soy proteins are most commonly used, although other proteins, such as wheat gluten, can also be used. Commonly abbrevi- ated to TVP. Texture profile analysis Analysis of the texture of a food in terms of mechanical properties, geometrical characteristics, and fat and moisture contents, at spe- cific points during the mastication process. Texturization Process by which sensory proper- ties of a substance are altered, e.g. to produce a par- ticular feel, appearance or consistency. Texturizers Additives that improve the texture of foods. Examples include gums, hydrocolloids and polydextrose, used as fat substitutes to add body to low fat foods and calcium chloride, which is added to canned fruits and vegetables to maintain firmness of the product. Texturizing agents Substances which act as textur- izers, improving the texture of foods. Texturometers Devices used to measure texture properties of foods, by analysis of physical attributes such as hardness, cohesiveness and crush resistance. Thaumatin Non-nutritive natural sweeteners iso- lated from fruits of Thaumatococcus daniellii, a plant native to West Africa. The sweet flavour of T. daniel- lii fruits is attributed to two sweet proteins of ap- proximately 22 kDa, designated thaumatin I and II. Both thaumatin proteins are approximately 1000-2000 times as sweet as sucrose (weight for weight). Com- mercial thaumatin preparations are complexed with aluminium to improve their stability. Thaumatin is soluble in water and alcohols and is synergistic with acesulfame K and saccharin. Aqueous solutions of the sweetener have high thermal stability and are stable over the pH range 2-10. However, factors which influ- ence thaumatin structure, e.g. reducing agents, affect its sweetness. Although used as a sweetener, thaumatin has a liquorice-like aftertaste. It is commonly used in flavour enhancers, e.g. in chewing gums. Syn- onymous with katemfe and sold under the trade name Talin. Thawing Transition of an item from a frozen to an unfrozen state. Theaflavins Flavonoids which contribute signifi- cantly to the colour and flavour of black tea, and are used as markers of quality. Possess antitumour activity and antioxidative activity. Theanine Amino acid found in tea. As well as im- proving the flavour of tea, theanine has a relaxing ef- fect, improves learning ability and lowers blood pres- sure. Has also been found to help prevent D - galactosamine-induced liver injury in rats. Thearubigins Flavonoid pigments found in tea which contribute to the flavour, depth of colour and body. Theobromine Purine alkaloid similar to caffeine that is found in cocoa, chocolate, soft drinks and tea. Acts as a stimulant and may be toxic. Theophylline Purine alkaloid that contributes to the flavour of and is used as a marker of quality in tea, coffee, soft drinks and chocolate. Acts as a stimu- lant. Therapy Treatment of diseases. Includes diet ther- apy and immunotherapy. Thermal capacity Thermophysical properties relating to the extent to which a material can retain heat. Thermal conductivity Thermophysical proper- ties relating to the rate of conduction of heat through a material, measured in Joules per second per metre per Kelvin. Thermal diffusivity Thermophysical properties relating to the extent to which an item diffuses or spreads heat throughout its mass. Thermal expansion Increase in size (e.g. length, volume, surface area) of a body in response to heat- ing. For liquids, expansivity observed directly is called the apparent expansivity, as the container holding the liquid will have expanded also with the rise in tem- perature. Absolute expansivity is the apparent expan- sivity plus the volume expansivity of the container. Thermal processes Processes involving heating that are used to produce desirable changes in products, such as protein coagulation, starch swelling, textural softening and formation of aroma compounds. Un- desirable changes can also occur with application of thermal processes, such as losses of vitamins and minerals, and loss of fresh appearance, flavour and texture. Examples of thermal processes used in the food industry are: HTST processing; LTLT process- ing; electric heating; ohmic heating; microwave heating; and blanching . Thermal processing Application of heating meth- ods to the processing of foods. Techniques in the cate- gory include: HTST processing; LTLT processing; electric heating; ohmic heating ; microwave heating; and blanching. Thermal properties Properties that influence the heating rate and response to heating of a material. Thermal stability Thermophysical properties relating to the ability of materials to maintain stability when subjected to various temperatures of applied heat. If food ingredients or additives are heat stable, it is possible for them to be used successfully in prod- 422 Thermistors Thermus ucts which have to be thermally processed. Synony- mous with heat stability. Thermistors Semiconductors used for measuring temperature on the basis that their electrical resistance decreases with increasing temperature. Thermization Heat treatment of foods at a temp. lower than that used for pasteurization, with an up- per limit of about 65°C for 20 s. Thermization is less severe for the product and associated microorgan- isms than pasteurization. Thermoanaerobacter Genus of anaerobic, rod- shaped, thermophilic Gram positive bacteria of the Thermoanaerobacteraceae family. Some species are used in the production of thermostable proteinases and other enzymes. Thermoanaerobacterium Genus of anaerobic, rod- shaped, thermophilic Gram positive bacteria be- longing to the Thermoanaerobacteraceae family. Some species (e.g. Thermoanaerobacterium thermosac- charolyticum) are used in the production of thermosta- ble proteinases and other enzymes. Thermoascus Genus of thermophilic filamentous fungi of the family Trichocomaceae. Thermoascus au- rantiacus shows strong cellulose degrading activity and is a source of a number of glycosidases, includ- ing xylan endo-1,3-ȕ-xylosidases and cellu- lolytic enzymes. Thermococcus Genus of archaea of the Thermo- coccaceae family. These hyper-thermophiles have biotechnological potential for production of enzymes with good thermal stability, including glycosi- dases and proteinases. Thermocouples Devices for measuring or sensing a temperature difference, consisting of two wires of dif- ferent metals connected at two points, between which a voltage is developed in proportion to any temperature difference. Thermodynamic properties Thermophysical properties which relate to the response of systems to changes in temperature, pressure and volume. Thermogenesis The production of heat, particularly within the body by physiological processes. Can be classified into exercise-associated thermogenesis and non-exercise-associated thermogenesis. May occur through the uncoupled oxidation of fatty acids by brown adipose tissues or shivering. Thermogravimetric analysis Alternative term for gravimetry . Thermoluminescence Luminescence produced by heating a solid substance. Caused by emission of photons of light by free electrons and holes trapped in the solid. Thermolysins EC 3.4.24.27, formerly 3.4.24.4. Neu- tral, heat-stable metalloendopeptidases produced by Bacillus thermoproteolyticus, containing 1 zinc ion and 4 calcium ions. Most heat-stable proteinases available commercially, remaining active at temp. up to 80qC. Thermometers Instruments for measuring and indi- cating temperature, typically consisting of a graduated glass tube containing mercury or alcohol which ex- pands when heated and contracts when the temperature falls. Thermometers are tailored for different purposes. For example, specific instruments are available for use during the manufacture of sugar confectionery or cooking of meat (to ascertain that the meat has reached the desired degree of doneness), and also for temperature monitoring in freezers, refrigerators and ovens. Thermomonospora Genus of aerobic, thermophilic, filamentous Gram positive bacteria of the family Thermomonosporaceae. Occur in soil and compost. Some species may be used in the production of ther- mostable proteinases. Thermomyces Genus of mitosporic fungi of the Ascomycota phylum. Species (e.g. Thermomyces la- nuginosus) are used in the production of thermostable lipases. Thermophiles Organisms, especially microorgan- isms, that grow best at relatively high temperatures. Their optimum growth temperature is generally ac- cepted as being above 50°C. Thermophilic bacteria Bacteria that are thermo- philes. Thermophysical properties Properties that influ- ence the heating rate and response to heating of a ma- terial. Examples of thermophysical properties are thermal conductivity (the ability of a material to conduct heat) and specific heat (the ability of a ma- terial to store heat). Thermostats Devices that automatically regulate temperature to a specified value or range, or activate devices at a set temperature. Thermotoga Genus of rod-shaped, hyperthermophilic bacteria belonging to the family Thermotogaceae. Thermotoga maritima and T. neapolitana metabolize many simple and complex carbohydrates and are a source of a number of enzymes including glycosi- dases. Thermus Genus of aerobic, rod-shaped or filamen- tous, thermophilic Gram negative bacteria. Occur in hot springs, hot water tanks and thermally polluted rivers. Thermus thermophilus is used in the production of thermostable proteinases. T. aquaticus is an ex- treme thermophile used in the production of a wide 423 Thiabendazole Thioglycolic acid range of thermostable enzymes, such as fructose- bisphosphate aldolases, DNA-directed RNA polymerases, DNA-directed DNA polymerases, alkaline phosphatases and isocitrate dehydro- genases. Thiabendazole A systemic benzimidazole fungicide with curative and protective action used to control fun- gal diseases in fruits, vegetables and cereals. Em- ployed in food preservation, such as in dips for im- proving the postharvest freshness of fruits. Also used as a broad-spectrum anthelmintic to treat a range of roundworm and cestode infections in livestock. Classi- fied by WHO as unlikely to present acute hazard in normal use. Also known as tecto. Thiamin Synonym for vitamin B 1 and vitamin F. Member of the water soluble vitamin B group. Ac- tive in the form thiamin pyrophosphate, a coenzyme for decarboxylation reactions in carbohydrate metabo- lism. Helps to maintain normal nervous system activity and regulates muscle tone of the gastrointestinal tract. Severe deficiency is clinically recognized as beriberi. Thiamin is found in unrefined cereals, beans, meat (especially livers, kidneys, hearts and pork), yeasts, potatoes, peas and nuts. Cooking losses can be as much as 50%. Thiamine Alternative spelling for thiamin. Thiamphenicol Synthetic, broad-spectrum antibiotic (chloramphenicol analogue) used for treatment and control of respiratory and intestinal diseases in live- stock, excluding animals producing eggs for human consumption. May also be used in aquaculture. Par- ticularly effective against anaerobes. Thiazoles Volatile flavour compounds found, for example, in cooked meat and beer. May also cause off flavour. Thickeners Additives that increase the viscosity of foods. Unlike gelling agents, do not promote the formation of gels. Gums and starch are important thickeners in the food industry. Thickening Process of making or becoming thicker and usually more viscous. For example, sauces are thickened using corn starch. Thickness As well as relating to consistency and viscosity, this term relates to measurement of the depth of a substance such as backfat on animal car- casses. Thidiazuron Plant growth regulator with defoliation activity; used to stimulate fruit growth in a range of fruits , including apples , grapes and kiwifruit. Thielaviopsis Genus of fungi of the order Microas- cales, which includes several agricultural pathogens. Species may cause spoilage of fruits and vegeta- bles. Carrots, for example, commonly harbour spores of Thielaviopsis basicola and T. thielavioides on their surface. T. basicola also causes black root rot of carrots. Thin layer chromatography Chromatography technique in which sample components are separated as the sample travels, under the influence of a solvent, up an inert plate coated with a sorbant. Commonly ab- breviated to TLC. Thin layer drying A drying technique that involves arrangement of the products to be dried in thin layers in order to optimize moisture transfer. Applied to a range of food particles or slices, particularly plant foods. Thinning In plant cultivation, removal of young plants to allow remaining plants more room to grow, or removal of selected fruits from a plant so that the other fruits can increase in size. Thiobarbituric acid values Values (commonly abbreviated to TBA values) used for assessing oxida- tion of lipids in foods and other biological systems, using thiobarbituric acid (TBA). Two molecules of TBA react with one molecule of malonaldehyde to produce a red pigment; the amount of pigment pro- duced is measured using spectroscopy. Extent of lipid oxidation, reported as the TBA value, is ex- pressed as milligrams of malonaldehyde equivalents per kilogram of sample, or as micromoles of malonal- dehyde equivalents per gram of sample. The TBA test may be performed directly on the sample, its extracts or distillate. Thiocyanates Alternative term for isothiocy- anates. Thiodan Alternative term for the insecticide endo- sulfan. Thioesters Esters containing sulfur instead of oxy- gen. Important aroma compounds often added to processed foods. Can be prepared by lipase- catalysed esterification of fatty acids with short- and long-chain thiols. Thioglucosidases EC 3.2.1.147, formerly 3.2.3.1. Glycosidases that hydrolyse S-glycosyl compounds. Have a wide specificity for thioglycosides, forming a thiol and a sugar. Responsible for hydrolysis of glu- cosinolates in cruciferous vegetables, producing organic sulfur compounds including isothiocy- anates, some of which display anticarcinogenic- ity, but which also impart an undesirable flavour and which may also be toxic. Also known as myrosinases, sinigrinases and sinigrases. Thioglycolic acid Toxic organic acid also known as 2-mercaptoacetic acid, Į-mercaptoacetic acid and thio- vanic acid. 424 Thioglycosides Thyme Thioglycosides Sulfur-containing glycosides found in cruciferous vegetables that show anticar- cinogenicity. They are useful as glycosyl donors in the synthesis of complex carbohydrates. Thiols Compounds containing sulfhydryl groups, i.e. in which the oxygen of an alcohol is replaced with sulfur. These compounds have extremely unpleasant odours. Thionins Low molecular weight proteins which occur in seeds of several plant species and show an- timicrobial activity. Thiophanate-methyl Systemic fungicide used for control of a wide range of fungal diseases on fruits, vegetables and cereals. Classified by WHO as unlikely to present acute hazard in normal use. Also known as methylthiophanate and Pelt 44. Thiophenes Sulfur-containing volatile com- pounds that contribute to the flavour of many foods and beverages. Thioredoxin Small, widely distributed, dithiol protein with antioxidative activity. Facilitates reduction of disulfide bonds in food proteins to sulfhydryl groups, reducing their allergenicity and increasing their digestibility by trypsin and pepsins. Used as an ingredient in functional foods. Ingestion of isothiocyanates from cruciferous vegetables can increase thioredoxin expression in mammals, leading to reduced oxidative stress. Thiouracil Drug which inhibits production of thyroid hormones and results in increased water retention in muscle tissue. Sometimes used illegally to increase meat yield in animals. Thiourea Organic nitrogen- and sulfur-containing compound, molecular formula (NH 2 ) 2 CS. Structurally similar to urea, with S replacing the O atom. Widely- used industrially, and can occur as an environmental contaminant in water supplies. Used in the food in- dustry as an analytical reagent and an enzyme inhibi- tor, particularly with regard to polyphenol oxi- dases (catechol oxidases). Has moderate radical scavenging activity. Thiram Protective dithiocarbamate fungicide applied to foliage or as seed treatments in order to control fun- gal diseases on a wide range of crops. Classified by WHO as slightly hazardous (WHO III). Also known as TMTD. Thirst A desire or need to drink that is often accompa- nied by a sensation of dryness in the mouth and throat. Commonly caused by an insufficient intake of fluids. Thistles Group of plants including many species used as vegetables. Such types include globe arti- chokes (Cynara scolymus), cardoons (C. carduncu- lus) and milk thistles (Silybum marianum). Parts which are eaten include flowers, leaves, stems and seeds. Ex- tracts of dried cardoon flowers are used as vegetable rennets in cheesemaking. Thixotropy Property of a material that enables it to stiffen in a relatively short time on standing, while, upon agitation or manipulation, it can change to a very soft consistency or to a fluid of high viscos- ity, the process being completely reversible. Thomsons gazelles Swift-running, graceful African antelopes that may be shot or snared for food use. Thomson's gazelles (Gazella thomsoni) are similar in appearance to Grant's gazelles, but are smaller and yield less meat when dressed. Thraustochytrium Genus of filamentous fungi-like microorganisms of the family Thraustochytriidae in the stramenopile taxonomic group. Fermentation products obtained from this organism include Ȧ-3 fatty acids, such as docosahexaenoic acid and eicosapentaenoic acid, and carotenoids. Its cofermentation with other stramenopiles of the ge- nus Schizochytrium is also used for production of PUFA. Threadfin bream Any of several marine fish spe- cies in the genus Nemipterus; distributed across the Indo-Pacific. Commercially important species include Nemipterus japonicus (Japanese threadfin bream) and N. virgatus (golde threadfin bream). Marketed mainly fresh, but also frozen, steamed, dried-salted, dry- smoked, fermented or made into fish balls and fish meal. Threonine Aminohydroxybutyric acid. One of the essential amino acids. Threshers Machines that separate grain from other debris. Thrips Common name for members of the insect order Thysanoptera. Pests of a wide variety of crops (e.g. citrus fruits, vegetables and cereals). Some spe- cies are important vectors of fungi and viruses re- sponsible for plant diseases. Thromboelastographs Instruments used in the food industry to monitor gelation, e.g. milk coagulation, by measuring gel firmness. Thujone Toxic ketone present in absinthe, and cer- tain herbal plants, essential oils and natural fla- vourings. Thyme Common name for plants native to Mediterra- nean countries of the genus Thymus, leaves and flower- ing tops of which are used as spices. The most com- monly used variety is T. vulgaris; other spice varieties include T. citriodorus (lemon thyme), T. zygis and T. serpyllum (wild thyme). The predominant flavour compounds of thyme are thymol and carvacrol. [...]... specific application Ultrastructure Detailed structure of organic materials or objects that can be observed by electron microscopy Ultraviolet Relating to electromagnetic radiation that has a wavelength in the range 100-400 nm, which is just shorter than that of violet light but longer than that of X-rays Abbreviated to UV Ultraviolet radiation Electromagnetic radiation in the ultraviolet range that has a... eukaryotes, some are necessary for the initiation of transcription, since they facilitate binding of the polymerase to genes at a transcription initiation site in their promoters Others regulate transcription efficiency by binding to specific sites within the promoters upstream of the transcription initiation site, and may stimulate or inhibit transcription constitutively or in response to a signal Mutations... shelled reptiles belonging to the order Chelonia, that are hunted for their meat and shells Turtle eggs may also be eaten Turtle meat has good flavour, but because of its chewiness, it tends to be used to prepare soups Most turtle meat is produced from sea turtles; however, meat from freshwater terrapins is often considered to have the best sensory properties amongst turtle meats Tutane Alternative term... tools that monitor food temperature exposure history and relate it to shelf life behaviour Time temp integrators should give accurate information and be easy to use, should be incorporated into food without disturbing heat transfer and should quantify the impact of the process on a target attribute that results in a specific kinetic requirement Time temp integrators are classified according to working... antioxidant that protects polyunsaturated fats and vitamin A from oxidation in the gastrointestinal tract -Tocopherol also prolongs the life of red blood cells and protects lung tissue from the adverse effects of pollution -Tocopherol is included among GRAS substances and is one of the antioxidants used in the food industry to retard rancidity in foods containing polyunsaturated fats -Tocopherol acetate Alternative... life milk UHT treatment Abbreviation for ultra-high temperature treatment, a brief, intense heat treatment (direct or indirect) used to sterilize foods prior to packaging Kills all microorganisms that would otherwise spoil the product Following UHT treatment, foods are filled into pre-sterilized containers in a sterile atmosphere Food products processed by UHT treatment include liquid products (e.g milk,... encoding transcription factors may result in genetic disorders Targeted mutation of these factors or alteration of the level of the signal to which the regulatory factors respond may be used to alter expression of target genes Gene-nutrient interactions may be mediated by transcription factors In bacteria, proteins Transglucosylases required for transcription initiation are termed factors Transducers... with soy sauces Turbidimetry Measurement of turbidity of a solution, usually using a turbidimeter, an instrument that records the loss of intensity of a light beam passed through a solution containing suspended particles Turbidity Optical properties relating to the extent to which a solution is turbid, i.e cloudy or hazy Turbidity in solutions is caused by the presence of finely suspended matter Turbot... product quality The transmittance of packaging materials is relevant when estimating the shelf life of foods since these materials can slow down degradation by blocking a portion of the incident light which can degrade food components Transparency Optical properties relating to the extent to which an item allows light to pass through it so that bodies can be clearly seen Transpeptidases Enzymes that catalyse... egg products, at a high temperature for a short time, sufficient to kill any pathogens present Used to extend the shelf life of the product without greatly affecting its nutritional properties A typical process for ultrapasteurization of milk would involve heating at 138 C for at least 2 seconds Ultrapasteurized products are aseptically packaged and stored under refrigeration Ultrasonics The science . electrodes in the reaction solution. Titrimetry Alternative term for titration. TLC Abbreviation for thin layer chromatography. TMTD Alternative term for the. The TBA test may be performed directly on the sample, its extracts or distillate. Thiocyanates Alternative term for isothiocy- anates. Thiodan Alternative

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