Tài liệu Tự điển Food Science, Technology And Nutrition - Vần Q,R ppt

Also known as saturation analysis or radio-ligand binding assay, especially when a binding protein or plasma transport protein is used rather than an antibody.. RDA Recommended daily or

initial product of protein glycation to the advanced glycation end-product); potentially useful in preventing the adverse effects

of poor glycaemic control in diabetes mellitus

pyridoxal, pyridoxamine, pyridoxine See vitamin B6

4-pyridoxic acid The main urinary metabolite of vitamin b6

pyridoxyllysine A schiff base formed by condensation between pyridoxal and the ε-amino group of lysine in proteins Renders both the vitamin b6 and the lysine unavailable, and also has antivitamin b6antimetabolic activity

pyrimidines Nitrogenous bases that occur in nucleic acids, cyto-sine, thymine and uracil

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pyrithiamin Antimetabolite of thiamin, used in experimental studies of vitamin b1deficiency; it inhibits thiamin pyrophospho-kinase (EC 2.7.6.2) and competes for uptake across the blood–brain barrier, accumulating in the central nervous system

See also oxythiamin.

pyrocarbonate See diethyl pyrocarbonate.

pyrosis Alternative name for heartburn (USA) See indigestion.

pyrroles Derivatives of five-membered heterocyclic compounds (C4H4NH) that impart a ‘burnt’ flavour to foods; mainly formed

by the maillard reaction

pyruvic acid An intermediate in the metabolism of carbohy-drates, formed by the anaerobic glycolysis of glucose It may then either be converted to acetyl CoA, and oxidised through the citric acid cycle or be reduced to lactic acid The oxidation

to acetyl CoA is thiamin dependent, and blood concentrations

of pyruvate and lactate rise in thiamin deficiency

Q QPM Quality protein maize

QUAC stick Quaker arm circumference measuring stick A stick used to measure height which also shows the 80th and 85th

PYRIMIDINES

centiles of expected mid-upper arm circumference Developed

by a Quaker Service Team in Nigeria in the 1960s as a rapid and simple tool for assessment of nutritional status

See also anthropometry.

quahog American bivalve mollusc, Venus mercenaria.

quail Formerly a game bird, now so endangered in the wild that shooting is prohibited, but farmed to some extent Two main

species, Bonasa umbellus and Colinus virginianus; Californian quail is Lophortyx californica The small eggs are prized as a

delicacy

Composition/100 g: (edible portion 76%) water 70 g, 561 kJ (134 kcal), protein 21.8 g, fat 4.5 g (of which 34% saturated, 34% mono-unsaturated, 32% polyunsaturated), cholesterol 70 mg, carbohydrate 0 g, ash 1.3 g, Ca 13 mg, Fe 4.5 mg, Mg 25 mg, P

307 mg, K 237 mg, Na 51 mg, Zn 2.7 mg, Cu 0.6 mg, Se 17.4µg, vitamin A 17µg retinol, B1 0.28 mg, B2 0.28 mg, niacin 8.2 mg,

B60.53 mg, folate 7µg, B120.5µg, pantothenate 0.8mg, C 7mg A

100 g serving is a source of Zn, vitamin B2, pantothenate, C, a good source of Se, vitamin B1, B6, a rich source of Cu, Fe, P, niacin, vitamin B12

quality assurance The planned actions necessary to provide ade-quate confidence that a product will satisfy requirements for quality

quality control The operational techniques and activities that are used to fulfil requirements for quality

quality management That aspect of management that determines and implements the quality policy

quality policy The overall quality intentions and direction of an organisation, formally expressed by management

quality system The organisational structure, responsibilities, pro-cedures and resources for implementing quality management

quamash Or camash; starchy roots of Camassia quamash,

for-merly the staple food of west coast native Americans

quantitative ingredients declaration (QUID) Obligatory on food labels in the EU since February 2000; previous legislation only required declaration of ingredients in descending order of quan-tity, not specific declaration of the amount of each ingredient present

quark (quarg) Originally German; unripened soft cheese, known

in France as fromage frais

quart Imperial measure of volume, equal to 1/4Imperial gallon or

2 pints (i.e 1.1 L) Reputed quart is the traditional ‘bottle’ of wine

or spirits; approximately 2/3Imperial quart, or 262/3fluid ounces (730 mL) Reputed pint is 131/3fluid ounces

quartern See noggin.

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quebracho Or aspidosperma; obtained from the bark of Aspi-dosperma quebrachoblanco; used as source of tannins and

alkaloids

queen substance See royal jelly.

quercitin A flavone (see flavonoids), found in onion skins, tea,

hops and horse chestnuts Not known to be a dietary essential or

to have any function in the body

quercitol See acorn sugar.

querns Pair of grinding stones used for pulverising grain (from about 4000–2000 bc) The lower stone was slightly hollowed and the upper stone was rolled by hand on the lower one

Quetelet’s index See body mass index.

quick breads Baked goods such as biscuits, muffins, popovers, griddles, cakes, waffles and dumplings, in which no yeast is used The raising is carried out quickly with baking powder or other chemical agents

quick freezing Rapid freezing of food by exposure to a blast of air at a very low temperature Unlike slow freezing, very small crystals of ice are formed, which do not rupture the cells of the food and so the structure is relatively undamaged A quick-frozen food is commonly defined as one that has been cooled from a temperature of 0 °C to −5° or lower, in a period of not more than 2 h and then cooled to −18°C

QUID See quantitative ingredients declaration.

quillaja (quillaia) Or soapbark; the dried bark of the shrub Quil-laja saponaria, which contains saponins and tannins Used to

produce foam in soft drinks, shampoos and fire extinguishers

quince Pear-shaped fruit of Cydonia oblongata, with flesh similar

to that of the apple; sour but strong aromatic flavour when cooked; rich in pectin and used chiefly in jams and jellies Composition/100 g: (edible portion 61%) water 84 g, 239 kJ (57 kcal), protein 0.4 g, fat 0.1 g, carbohydrate 15.3 g, fibre 1.9 g, ash 0.4 g, Ca 11 mg, Fe 0.7 mg, Mg 8 mg, P 17 mg, K 197 mg, Na 4 mg, Cu 0.1 mg, Se 0.6µg, vitamin A 2µg RE, B10.02 mg, B20.03 mg, niacin 0.2 mg, B60.04 mg, folate 3µg,pantothenate 0.1mg,C 15mg.A 90g serving (1 fruit) is a good source of vitamin C

Japanese quince is fruit of the ornamental shrub Chaenomeles lagenaria, hard, sour and aromatic, used in preserves and jellies.

quinine Bitter alkaloid extracted from bark of the cinchona tree

(Cinchona officinalis), formerly used to treat or prevent malaria

and in apéritif wines, bitters and tonic water

quinoa Glutinous seeds of the south American plant

Chenopodium album, used in Chile and Peru to make bread.

Composition/100 g: water 9.3 g, 1566 kJ (374 kcal), protein 13.1 g, fat 5.8 g (of which 14% saturated, 34% mono-unsaturated,

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52% polyunsaturated),carbohydrate 68.9 g,fibre 5.9 g,ash 2.9 g,Ca

60 mg, Fe 9.3 mg, Mg 210 mg, P 410 mg, K 740 mg, Na 21 mg, Zn 3.3 mg, Cu 0.8 mg, Mn 2.3 mg, vitamin B10.2 mg, B20.4 mg, niacin 2.9 mg, B60.22 mg, folate 49µg, pantothenate 1mg A 30g serving

is a source of Fe, P, a good source of Cu, Mg, a rich source of Mn

quintal 100 kg (220 lb)

QuornTM mycoprotein from the mould Fusarium graminearum.

R

R- and S- Systematic chemical nomenclature for assigning con-formation of four different groups around an asymmetric carbon

atom, in which the two isomers are R- (for rectus, right) and S-(for sinistra, left) It is based on a hierarchy of substituent groups,

and does not give the same conformation for all the naturally occurring amino acids, unlike the dl-system It is little used in biochemistry and nutrition, apart from naming the isomers of vitamin e

See also d-, l- and dl-; optical activity.

rabbit (1) Lepus cuniculus; both wild and farmed rabbits are

eaten

Composition/100 g: water 73 g, 569 kJ (136 kcal), protein 20 g, fat 5.6 g (of which 40% saturated, 35% mono-unsaturated, 26% polyunsaturated), cholesterol 57 mg, carbohydrate 0 g, ash 0.7 g,

Ca 13 mg, Fe 1.6 mg, Mg 19 mg, P 213 mg, K 330 mg, Na 41 mg, Zn 1.6 mg, Cu 0.1 mg, Se 23.7µg, vitamin B10.1 mg, B20.15 mg, niacin 7.3 mg, B60.5 mg, folate 8µg, B127.2µg, pantothenate 0.8mg A

210 g serving (half rabbit) is a source of Cu, Mg, vitamin B1, B2,

a good source of Fe, Zn, pantothenate, a rich source of P, Se, niacin, vitamin b6, b12

(2) Original form of rarebit, see welsh rarebit.

racemic The mixture of the d- and l-isomers of a compound, commonly shown as dl-

rad A non-SI unit of the energy absorbed from ionising radiation; the absorption of 100 ergs per gram of substance Now super-seded by the gray

radappertisation Sterilisation of food by high-dose irradiation for destruction of (virtually) all organisms

See also radicidation; sterile.

radiation sterilization See irradiation.

radical (free radical) A highly reactive molecular species with an unpaired electron

radicchio Red variety of chicory

Composition/100 g: (edible portion 91%) water 93 g, 96 kJ 402

(23 kcal), protein 1.4 g, fat 0.3 g, carbohydrate 4.5 g (0.6 g sugars), fibre 0.9 g, ash 0.7 g, Ca 19 mg, Fe 0.6 mg, Mg 13 mg, P 40 mg, K

302 mg, Na 22 mg, Zn 0.6 mg, Cu 0.3 mg, Mn 0.1 mg, Se 0.9µg, vitamin A 1µg RE (8848µg carotenoids), E 2.3mg, K 255.2mg,

B10.02 mg, B20.03 mg, niacin 0.3 mg, B60.06 mg, folate 60µg, pan-tothenate 0.3 mg, C 8 mg

radicidation Low-level irradiation treatment to kill non-spore-forming pathogens and prevent food poisoning; less severe treat-ment than radappertisation

radioallergosorbent tests (RAST) Tests for food allergy See

adverse reactions to foods

radio frequency heating See microwave cooking.

radioimmunoassay (RIA) Sensitive and specific analytical tech-nique for determination of analytes present at very low concen-trations in biological samples Based on competition between unlabelled and labelled analyte for a limited number of binding sites on an antibody; after calibration, measurement of either the bound or unbound labelled analyte permits determination of the amount present in the sample Bound and free analyte may be separated by a variety of techniques, including ultrafiltration, solvent extraction, equilibrium dialysis, adsorption onto charcoal and binding of the antiserum to a solid phase

Also known as saturation analysis or radio-ligand binding assay, especially when a binding protein or plasma transport protein is used rather than an antibody

See also elisa; fluorescence immunoassay.

radio-ligand binding assay See radioimmunoassay.

radiolysis Chemical changes caused by irradiation, producing compounds that have antibacterial activity

radish The root of Raphanus spp.

Composition/100 g: (edible portion 90%) water 95 g, 67 kJ (16 kcal), protein 0.7 g, fat 0.1 g, carbohydrate 3.4 g (2.1 g sugars), fibre 1.6 g, ash 0.6 g, Ca 25 mg, Fe 0.3 mg, Mg 10 mg, P 20 mg, K

233 mg, Na 39 mg, Zn 0.3 mg, Cu 0.1 mg, Mn 0.1 mg, Se 0.6µg,

14µg carotenoids, vitamin K 1.3mg, B1 0.01 mg, B2 0.04 mg, niacin 0.3 mg, B6 0.07 mg, folate 25µg, pantothenate 0.2mg, C

15 mg

radurisation pasteurisation of food by low-dose irradiation to destroy a sufficient number of yeasts, moulds and non-spore-forming bacteria to prolong shelf-life

raffinade Best-quality refined sugar

raffinose Trisaccharide, galactosyl-glucosyl-fructose, found in cotton seed, sugar-beet molasses and Australian manna; also known as gossypose, melitose or melitriose 23% of the sweet-ness of sucrose Not digested

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RaftilineTM fat replacer made from non-starch polysaccharide.

RaftiloseTM Fructo-oligosaccharide derived from inulin, a prebiotic

ragi Dried balls of starter containing moulds, yeast and bacteria

on cereal or starch, used as a starter inoculation for production

of lao-chao, saké, tape, and other fermented foods

raisin Dried seedless grapes of several kinds Valencia raisins from Spanish grapes; Thompson seedless raisins produced mainly in California from the sultanina grape (the skins are coarser than the sultana)

Composition/100 g: water 15.4 g, 1252 kJ (299 kcal), protein 3.1 g, fat 0.5 g, carbohydrate 79.2 g (59.2 g sugars), fibre 3.7 g, ash 1.9 g, Ca 50 mg, Fe 1.9 mg, Mg 32 mg, P 101 mg, K 749 mg, Na

11 mg, Zn 0.2 mg, Cu 0.3 mg, Mn 0.3 mg, Se 0.6µg, vitamin E 0.1 mg, K 3.5 mg, B10.11 mg, B20.13 mg, niacin 0.8 mg, B60.17 mg, folate 5µg, pantothenate 0.1mg, C 2mg

raisin oil Extracted from the seeds of muscat grapes, which are removed before drying them to yield raisins The oil is used pri-marily to coat the raisins to prevent them sticking together,

to render them soft and pliable and less subject to insect infestation

raising powder See baking powder.

rambutan Fruit of Nephelium lappaceum; covered with

yellowish-red soft spines with large seed surrounded by white juicy flesh, similar to lychee, and sometimes called hairy lychee The name

means hairy man of the jungle in Bahasa-Malay, reflecting the

appearance of the fruit

ramekin (1) Porcelain or earthenware mould in which a mixture

is baked and then brought to the table, or the savoury served in

a ramekin dish Paper soufflé cases are called ramekin cases (2) Formerly the name given to toasted cheese; now tarts filled with cream cheese

rancidity The development of unpleasant flavours in oils and fats

as a result of lipase action or oxidation

See also acid number.

rancimat Apparatus for determining oxidative stability of fats by dissolving the gases produced by oxidation in distilled water and measuring electrical conductivity

See also active oxygen method.

randomisation of fats See interesterification.

ranitidine See histamine receptor antagonists.

Rankine scale See temperature, absolute.

rapeseed Brassica napus and B rapa, also known as cole, coleseed

or colza Grown for its seed, as source of oil for both industrial and food use Varieties low in erucic acid are termed ‘0’ or single 404

low (also called canbra oil); varieties low in glucosinolates and erucic acid yield canola oil

rarebit See welsh rarebit.

rasgulla Indian; dessert of small balls of milk curd, ground almond and semolina, boiled in syrup

rasher Slice of bacon or ham

raspberry Fruit of Rubus idaeus Black raspberry is Rubus occi-dentalis, native of eastern USA.

Composition/100 g: (edible portion 96%) water 85.8 g, 218 kJ (52 kcal), protein 1.2 g, fat 0.6 g, carbohydrate 11.9 g (4.4 g sugars), fibre 6.5 g, ash 0.5 g, Ca 25 mg, Fe 0.7 mg, Mg 22 mg, P 29 mg, K

151 mg, Na 1 mg, Zn 0.4 mg, Cu 0.1 mg, Mn 0.7 mg, Se 0.2µg, vitamin A 2µg RE (164µg carotenoids), E 0.9mg, K 7.8mg, B1

0.03 mg, B20.04 mg, niacin 0.6 mg, B60.05 mg, folate 21µg, pan-tothenate 0.3 mg, C 26 mg A 110 g serving is a source of folate, a rich source of Mn, vitamin C

RAST Radio-allergosorbent tests for food allergy; see adverse

reactions to foods

rastrello Sharp-edged spoon used to cut out the pulp from halved citrus fruit

ratafia (1) Flavouring essence made from bitter almonds (2) Small macaroon-like biscuits flavoured with almonds (3) Almond-flavoured liqueur

rat line test Obsolete biological assay for vitamin d Rats were maintained on a rachitogenic (rickets-inducing) diet, then given the test substance or standard vitamin D for 7–10 days At post-mortem examination the long bones were stained with silver nitrate; in newly calcified regions silver phosphate is precipitated, and on exposure to light gives a stain that can be quantified

ravioli Square envelope of pasta stuffed with minced meat or cheese

raw sugar Brown unrefined sugar, 96–98% pure, as imported for refining Contaminated with mould spores, bacteria, cane fibre and dirt

ray Cartilaginous fish, Raja spp.

RBP See retinol binding protein.

RDA Recommended daily (or dietary) allowance (or amount) of

nutrients; see reference intakes.

RE Retinol equivalents, see vitamin B.

reactive oxygen species (ROS) A variety of compounds derived from oxygen, including superoxide, hydroxyl and perhydroxyl radicals, hydrogen peroxide and singlet oxygen

rebaudioside Very sweet substance extracted from the leaves of

Stevia rebaudiana (same source as stevioside); 400 times as

sweet as sucrose

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recombinant DNA Product of ligating (joining) two separate pieces of DNA, produced using the same restriction enzyme, so

as to permit introduction of foreign DNA into a host genome or plasmid

recommended daily amount (or allowance), RDA See reference

intakes

recrystallisation Changes in shape, size or orientation of ice crys-tals in frozen foods that cause a loss of quality

rectal feeding Also known as nutrient enemata The colon can absorb 1–2 L of solution per day; maximum daily amount of glucose that can be given is 75 g (equivalent to 1260 kJ, 300 kcal), and 1 g of nitrogen, in the form of hydrolysed protein (equiva-lent to 6 g of protein)

red blood cells See blood cells.

red colours amaranth (E-123), carmoisine (E-122), cochineal 120), erythrosine 127), ponceau 4r 124), red 2G (E-128)

red cooking Chinese method of cooking; meat or poultry is first stir fried, then simmered in broth or water

redcurrants Fruit of Ribes sativum (same species as

whitecur-rants); the UK National Fruit Collection contains 78 varieties Composition/100 g: (edible portion 98%) water 84 g, 234 kJ (56 kcal), protein 1.4 g, fat 0.2 g, carbohydrate 13.8 g (7.4 g sugars), fibre 4.3 g, ash 0.7 g, Ca 33 mg, Fe 1 mg, Mg 13 mg, P 44 mg, K

275 mg, Na 1 mg, Zn 0.2 mg, Cu 0.1 mg, Mn 0.2 mg, Se 0.6µg, vitamin A 2µg RE (72µg carotenoids), E 0.1mg, K 11mg, B1

0.04 mg, B20.05 mg, niacin 0.1 mg, B6 0.07 mg, folate 8µg, pan-tothenate 0.1 mg, C 41 mg.A 110 g serving a rich source of vitamin C

red fish See rosefish.

red herring herring that has been well salted and smoked for about 10 days Also called Yarmouth bloater Bloaters are salted less and smoked for a shorter time; kippers lightly salted and smoked overnight

redox potential Oxidation/reduction potential, the potential of an electrode in a 1 mol /L solution of each of the oxidant and reduc-tant, relative to a hydrogen electrode

red pepper See pepper, sweet.

red tide Sudden, unexplained increase in numbers of toxic dinoflagellate organisms in the sea which cause fish and shellfish feeding on them to become seasonally toxic

reduced EU and US legislation state that for a food label or advertising to bear a claim that it contains a reduced amount of fat, saturates, cholesterol, sodium or alcohol it must contain 25% less of the specified nutrient than a reference product for which 406

no claim is made A food may not claim to have a reduced content of a nutrient if it is already classified as low in or free from that nutrient

reducing sugars sugars that are chemically reducing agents, including glucose, fructose, lactose, many pentoses, but not sucrose

reduction See oxidation.

reduction rolls See milling.

reference intakes (of nutrients) Amounts of nutrients greater than the requirements of almost all members of the population, determined on the basis of the average requirement plus twice the standard deviation, to allow for individual variation in requirements, and thus covering the theoretical needs of 97.5%

of the population Reference intakes for energy are based on the average requirement, without the allowance for individual vari-ation Used for planning institutional catering, assessing the ade-quacy of diets of groups of people, but not strictly applicable to individuals Tables of reference intakes published by different national and international authorities differ because of differ-ences in the interpretation of the available data

Variously called in different countries and by different expert committees: RDA, the recommended daily (or dietary) amount (or allowance); RDI, recommended daily (or dietary) intake; RNI, reference nutrient intake; PRI, population reference

intake; safe allowances See Tables 3-6.

Levels of intake below that at which health and metabolic integrity are likely to be maintained are generally taken as the average requirement minus twice the standard deviation Vari-ously known as minimum safe intake (MSI), lower reference nutrient intake (LRNI) or lowest threshold intake

reference man, woman An arbitrary physiological standard; defined as a person aged 25, weighing 65 kg, living in a temper-ate zone of a mean annual temperature of 10 °C Reference man performs medium work, with an average daily energy require-ment of 13.5 MJ (3200 kcal) Reference woman is engaged in general household duties or light industry, with an average daily requirement of 9.7 MJ (2300 kcal)

reference nutrient intake, RNI See reference intakes.

reference protein See protein, reference.

refractive index Measure of the bending or refraction of a beam

of light on entering a denser medium (the ratio between the sine

of the angle of incidence of the ray of light and the sine of the angle of refraction) It is constant for pure substances under stan-dard conditions Used as a measure of sugar or total solids in solution, purity of oils, etc

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refractometer Instrument to measure the refractive index The Abbé refractometer consists of two prisms between which the substance under examination (jam, fruit juice, sugar syrup, etc.)

is spread, and light is reflected through the solution The immer-sion refractometer dips into the solution

refried beans See frijoles.

refrigerants Cooling agents in refrigerators and freezers; origi-nally ammonia or carbon dioxide were used, subsequently replaced by chlorofluorocarbons (CFCs), freons and arctons Because of the persistence of CFCs in the upper atmosphere, where they destroy the protective ozone layer, manufacture of fully halogenated chlorofluorocarbons (CFCs) ceased in most countries in 1995, and they are being replaced by hydrofluoro-carbons (HFCs) and hydrochlorofluorohydrofluoro-carbons (HCFCs), some-times collectively known as hydrofluoroalkanes (HFAs), although production of these compounds is to be phased out by 2015–2020

See also heat pump.

refrigeration, mechanical Equipment that evaporates and com-presses a refrigerant in a continuous cycle, using the cooled air, cooled liquid or cooled surfaces to freeze foods

regional enteritis See crohn’s disease.

Rehfuss tube A small diameter tube with a slotted metal tip for removing samples of food from the stomach after a test meal

See also ryle tube.

Reichert–Meissl number Measure of the steam-volatile fatty acids in a lipid

See also kirschner number; polenske number; steam

distil-lation

relative dose response test For vitamin A status The increase in circulating retinol binding protein after an oral dose of vitamin A; greater in vitamin A deficient subjects because in the absence

of vitamin A reserves in the liver there is accumulation of the apo-protein

relative humidity See humidity.

relative protein value A measure of protein quality

release agents Compounds used to lubricate surfaces that come into contact with food to prevent ingredients and finished prod-ucts from sticking to them, e.g fatty acid amides, microcrystalline waxes, petrolatums, starch, methyl cellulose

relish Culinary term for any spicy or piquant preparation used to enhance flavour of plain food

remove Obsolete term for the main course of dinner

RemylineTM fat replacer made from starch

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