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malt, malt extract Mixture of starch breakdown products taining mainly maltose malt sugar, prepared from barley orwheat.. Themixture is then extracted with hot water, and this malt extra

lymphocytes See leucocytes.

lymphokine See cytokine.

lyophilic A solute that has a high affinity for the solvent medium.When the solvent is water the term hydrophilic is used

lyophilisation See freeze drying.

lyophobic A solute that has little or no affinity for the solventmedium.When the solvent is water the term hydrophobic is used

lysergic acid The toxin of ergot

lysine An essential amino acid, abbr Lys (K), Mr146.2, pKa2.16,9.18, 10.79, codons AAPu Of nutritional importance, since it isthe limiting amino acid in many cereals

lysinoalanine An amino acid formed when proteins are heated ortreated with alkali by reaction between ε-amino group of lysineand dehydroalanine formed from cysteine or serine Present inmany foods at about 1000 ppm Although high doses causekidney tubule lesions (nephrocytomegaly) in rats, it is not con-sidered hazardous to health

lysolecithin lecithin from which the fatty acid at carbon-2 hasbeen removed

lysozyme An enzyme (EC 3.2.1.17) that hydrolyses high lar weight carbohydrates of bacterial cell walls, and so lyses bacteria Widely distributed (e.g in tears); egg white is especiallyrich

molecu-lyxoflavin An analogue of riboflavin isolated from human heartmuscle, containing the sugar lyxose; its function is unknown

lyxulose See xylulose.

M

MA Modified atmosphere See packaging, modified atmosphere.

maasa W African; shallow fried cakes made from millet orsorghum dough that has been allowed to undergo lactic acid bac-terial fermentation for a short time

maatjes See matjes herring.

macadamia nut Or Queensland nut, fruit of Macadamia ternifolia.

Composition/100 g: (edible portion 31%) water 1.4 g, 3006 kJ(718 kcal), protein 7.9 g, fat 75.8 g (of which 17% saturated, 81%mono-unsaturated, 2% polyunsaturated), carbohydrate 13.8 g(4.6 g sugars), fibre 8.6 g, ash 1.1 g, Ca 85 mg, Fe 3.7 mg, Mg

130 mg, P 188 mg, K 368 mg, Na 5 mg, Zn 1.3 mg, Cu 0.8 mg, Mn4.1 mg, Se 3.6µg, vitamin E 0.5mg, B11.2 mg, B20.16 mg, niacin2.5 mg, B60.28 mg, folate 11µg, pantothenate 0.8mg, C 1mg A

10 g serving (6 nuts) is a source of Mn

macaroni, maccaroncelli See pasta.

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macassar gum See agar.

mace See nutmeg.

macedoine Mixture of fruits or vegetables, diced, or cut into smalleven-shaped pieces

macerases A group of enzymes (usually extracted from the

mould Aspergillus) used to break down pectin in fruits to

faci-litate maximum extraction of the juice

mackerel An oily fish, Scomber scombrus.

Composition/100 g: water 63.5 g, 858 kJ (205 kcal), protein 18.6 g, fat 13.9 g (of which 27% saturated, 45% mono-unsaturated, 27% polyunsaturated), cholesterol 70 mg, carbohy-drate 0 g, ash 1.4 g, Ca 12 mg, Fe 1.6 mg, Mg 76 mg, P 217 mg, K

314 mg, Na 90 mg, Zn 0.6 mg, Cu 0.1 mg, Se 44.1µg, I 140µg,vitamin A 50µg RE (50µg retinol, E 1.5mg, K 5mg, B10.18 mg,

B2 0.31 mg, niacin 9.1 mg, B6 0.4 mg, folate 1µg, B12 8.7µg,pantothenate 0.9 mg A 100 g serving is a source of Fe, vitamin E,

B1, B2, pantothenate, a good source of Mg, P, vitamin B6, a richsource of I, Se, niacin, vitamin B12

macon ‘bacon’ made from mutton

maconochie A canned meat stew much used in the First WorldWar; made by Maconochie Brothers

macrobiotic diet A system of eating associated with Zen Buddhism; consists of several stages finally reaching Diet 7 which

is restricted to cereals Cases of severe malnutrition have beenreported on this diet Based loosely on the Buddhist concept of

yin and yang whereby foods (and indeed everything in life) are

predominantly one or the other and must be balanced

macrocytes Large immature precursors of red blood cells found

in the circulation in pernicious anaemia (see anaemia

perni-cious) and in vitamin b12and folic acid deficiency, due to ment of the normal maturation of red cells; hence macrocyticanaemia

impair-macrogols Polyethylene glycols used as osmotic laxatives

mad cow disease Bovine spongiform encephalopathy, see bse.

Madeira nuts See walnuts.

Madeira wines Fortified wines from the island of Madeira: sercial(dry); verdelho (semi-dry); bual (semi-sweet); malmsey (sweet)

madidi See kenkey.

MAFF Former UK Ministry of Agriculture, Fisheries and Food,now replaced by defra, the Department of the Environment,Food and Rural Affairs

magma Mixture of sugar syrup and sugar crystals producedduring sugar refining

magnesium An essential mineral; present in all human tissues,especially bone Involved in the metabolism of atp Present in

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chlorophyll and so in all green plant foods, and therefore generally plentiful in the diet Deficiency in human beings leads to disturbances of muscle and nervous system; in cattle, grass tetany Magnesium-deficient plants are yellow(chlorosed).

Magnesium salts (especially the sulphate, epsom salts) areused as osmotic laxatives because they are poorly absorbedfrom the small intestine; magnesium hydroxide (milk of magne-sia) and carbonate are used as antacids; magnesium trisilicate isused in the treatment of peptic ulcers

magnetic field system For detection of magnetic metals in foods.The food is passed through a strong magnetic field; any particle

of magnetic material is magnetised, and this generates a voltage

in a detector coil Can be used for foods in aluminium cans, sincealuminium is non-magnetic

See also balanced coil system.

magnum Double size wine bottle, 1.5 L

maheu African; sour non-alcoholic beverage made from maize ormillet by lactic acid fermentation

mahi-mahi See dolphin fish.

mahleb Spice prepared from black cherry kernels, Syrian inorigin, widely used in Greek baked goods

maidenhair tree See gingko.

maids of honour Small tartlets filled with almond-flavouredcustard; said to have originated in the court of Henry VIII, wherethey were made by Anne Boleyn when she was lady-in-waiting

to Catherine of Aragon

Maillard reaction Non-enzymic reaction between lysine in teins and reducing sugars, leading to a brown colour A similarreaction occurs in the glycation of proteins in diabetes mellitus.The first step in the reaction is the formation of a Schiff base(aldimine) between the aldehyde group of the sugar and the ε-amino group of lysine, followed by isomerisation (Amadorirearrangement) May also occur with other amino acids at theamino terminal of a protein

pro-It takes place on heating or prolonged storage and is one ofthe deteriorative processes that take place in stored foods It isaccompanied by a loss in nutritional value, since the amino acidthat reacts with the sugar is not available

See also availability; available lysine.

maître d’hôtel Simply prepared dishes garnished with buttercreamed with parsley and lemon juice (maître d’hôtel butter);

literally in the style of the chief steward Used especially in the

USA as a term for the head waiter

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maize Grain of Zea mays, also called Indian corn and (in USA)

simply corn Staple food in many countries, made into tortillas

in Latin America, polenta in Italy, and flaked as corn flakesbreakfast cereal; various preparations in the southern states ofthe USA are known as hominy, samp and cerealine

Two varieties of major commercial importance are flint corn

(Zea mays indurata), which is very hard, and dent corn (Z mays dentata); there is also sweet corn Z mays saccharata, and a variety that expands on heating (Zea mays everta; see popcorn) The starch prepared from Z mays dentata is termed cornflour;

the ground maize is termed maize meal There is a white variety;the usual yellow colour is partly due to cryptoxanthin (a vitamin

A precursor) Because of its low content of the amino acid tophan (and available niacin), diets based largely on maize areassociated with the development of pellagra

tryp-Yellow sweet corn, composition/100 g: (edible portion 36%)water 76 g, 360 kJ (86 kcal), protein 3.2 g, fat 1.2 g (of which 18%saturated, 27% mono-unsaturated, 55% polyunsaturated), car-bohydrate 19 g (3.2 g sugars), fibre 2.7 g, ash 0.6 g, Ca 2 mg, Fe 0.5 mg, Mg 37 mg, P 89 mg, K 270 mg, Na 15 mg, Zn 0.4 mg, Cu 0.1 mg, Mn 0.2 mg, Se 0.6µg, vitamin A 10µg RE (961µgcarotenoids), E 0.1 mg, K 0.3 mg, B1 0.2 mg, B2 0.06 mg, niacin 1.7 mg, B60.05 mg, folate 46µg, pantothenate 0.8mg, C 7mg A

90 g serving (1 cob) is a source of Mg, vitamin B1, pantothenate,

a good source of folate

maize, flaked Partly gelatinised maize used for animal feed Thegrain is cracked to small pieces, moistened, cooked and flakedbetween rollers

maize flour Highly refined and very finely ground maize mealfrom which all bran and germ have been removed

Composition/100 g: water 10.9 g, 1511 kJ (361 kcal), protein 6.9 g, fat 3.9 g (of which 15% saturated, 30% mono-unsaturated,55% polyunsaturated), carbohydrate 76.8 g (0.6 g sugars), fibre13.4 g, ash 1.5 g, Ca 7 mg, Fe 2.4 mg, Mg 93 mg, P 272 mg, K

315 mg, Na 5 mg, Zn 1.7 mg, Cu 0.2 mg, Mn 0.5 mg, Se 15.4µg,vitamin A 11µg RE (1515µg carotenoids), E 0.4mg, K 0.3mg, B1

0.25 mg, B20.08 mg, niacin 1.9 mg, B60.37 mg, folate 25µg, tothenate 0.7 mg

pan-maize oil See corn oil.

maize, quality protein (QPM) A hybrid derived from the Opaque

II strain, with a 10% higher yield than conventional maize, and70–80% more tryptophan and lysine

maize rice Finely cut maize with bran and germ partly removed,also called mealie rice

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maize starch, waxy starch obtained from hybrids of maize sisting wholly or largely of amylopectin, compared with ordinarymaize starch with 26% amylose and 74% amylopectin The paste

con-is semi-translucent, cohesive and does not form a gel

malabsorption syndrome Defect of absorption of one or morenutrients; signs include diarrhoea, steatorrhoea, abdominaldistension, weight loss and specific signs of nutrient deficiency

malacia Abnormal softening of tissue or organ See

keratomala-cia; osteomalacia

malai Indian; cream prepared by boiling milk, leaving it to cooland then skimming off the clotted cream

malic acid Dicarboxylic acid (COOH—CHOH—CH2—COOH);

a metabolic intermediate occurring in many fruits, particularly inapples, tomatoes and plums Used as a food additive to increaseacidity (E-296)

mallorising pasteurisation at high temperatures (up to 130 °C)

malmsey See madeira wines.

malnutrition Disturbance of form or function arising from ciency or excess of one or more nutrients

defi-See also cachexia; obesity; protein–energy malnutrition;

vitamin a toxicity; vitamin b6toxicity)

malolactic fermentation The conversion of the malic acid in grapejuice (and other fruit juices) into lactic acid, especially in redwines and cider as they mellow and become less acidic

malpighia See cherry, west indian.

malt, malt extract Mixture of starch breakdown products taining mainly maltose (malt sugar), prepared from barley orwheat The grain is allowed to sprout, when the enzyme diastase(amylase) develops and hydrolyses the starch to maltose Themixture is then extracted with hot water, and this malt extractcontains a solution of starch breakdown products together withdiastase Malt extract may be the concentrated solution or eva-porated to dryness

con-maltase Enzyme (EC 3.2.1.20) that hydrolyses maltose

malt flour Germinated barley or wheat, in dried form As well asdextrins, glucose, proteins and salts derived from the cereal, it isrich in diastase and is added to wheat flour of low diastaticactivity for breadmaking; used as an ingredient of malt loaf

Malthus, Thomas Robert (1766–1835), author of an Essay on the Principles of Population (1798), postulating that any temporary

or local improvement in living conditions will increase tion faster than the food supply, and that disasters such as warand pestilence, which check population growth, are inescapablefeatures of human society

popula-maltin, maltodextrin See dextrose equivalent value.

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maltitol A sugar alcohol produced by hydrogenation of tose Slowly hydrolysed in the digestive tract to glucose and sor-bitol and fairly completely utilised, providing 16 kJ (4 kcal)/g;sweeter than maltose, and 90% as sweet as sucrose (E-965).

mal-maltobiose See maltose.

maltol Also called laxarinic acid, palatone, veltol; chemically hydroxy 2-methyl-γ-pyrone Found in the bark of young larchtrees, pine needles, chicory and roasted malt; synthesised for use

3-as a fragrant, caramel-like flavour for addition to foods; imparts

a ‘freshly baked’ flavour to bread and cakes

maltonic acid See gluconic acid.

maltose Malt sugar, or maltobiose, a disaccharide, glucosyl-glucose Hydrolysed by maltase Does not occur infoods (unless specifically added as malt) but formed during theacid or enzymic hydrolysis of starch 33% as sweet as sucrose

α-1,4-maltose figure See diastatic activity.

maltose intolerance See disaccharide intolerance.

malt sugar See maltose.

mamey Fruit of the central American tree Pouteria sapota, times known as sapote.

some-Composition/100 g: (edible portion 60%) water 86 g, 213 kJ (51 kcal), protein 0.5 g, fat 0.5 g, carbohydrate 12.5 g, fibre 3 g, ash0.3 g, Ca 11 mg, Fe 0.7 mg, Mg 16 mg, P 11 mg, K 47 mg, Na 15 mg,

Zn 0.1 mg, Cu 0.1 mg, Se 0.6µg, vitamin A 12µg RE, B10.02 mg,

B2 0.04 mg, niacin 0.4 mg, B60.1 mg, folate 14µg, pantothenate 0.1 mg, C 14 mg A 200 g serving (quarter fruit) is a source of Cu,folate, a rich source of vitamin C

manchego Spanish sheep’s milk hard cheese

mandarin Loose-skinned citrus fruit, Citrus reticulata or C nobilio Varieties include satsumas and tangerines (although all

three names are used indiscriminately) with various hybridsincluding tangelo, tangor, temple, clementine

manganese An essential trace mineral which functions as theprosthetic group in a number of enzymes Dietary deficiency hasnot been reported in humans; in experimental animals man-ganese deficiency leads to impaired synthesis of mucopolysac-charides Requirements are not known; a safe and adequateintake has been set at 1.8 (women) to 2.3 (men) mg/day

mangelwurzel, mangoldwurzel A root vegetable used as cattle

feed, Beta vulgaris rapa; a cross between red and white beetroot.

mange tout See pea, mange tout.

mango Fruit of Mangifera indica, originally of Indo-Burmese

origin and now grown widely throughout the tropics; ovoid,with orange-coloured sweet aromatic flesh surrounding a centralstone

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Composition/100 g: (edible portion 69%) water 81.7 g, 272 kJ(65 kcal), protein 0.5 g, fat 0.3 g, carbohydrate 17 g (14.8 g sugars),fibre 1.8 g, ash 0.5 g, Ca 10 mg, Fe 0.1 mg, Mg 9 mg, P 11 mg, K

156 mg, Na 2 mg, Cu 0.1 mg, Se 0.6µg, vitamin A 38µg RE (473µg carotenoids), E 1.1mg, K 4.2mg, B10.06 mg, B20.06 mg,niacin 0.6 mg, B6 0.13 mg, folate 14µg, pantothenate 0.2mg, C

28 mg A 100 g serving (half fruit) is a source of vitamin E, a richsource of vitamin C

mangosteen Fruit of Garcinea mangostana, the size of an orange

with thick purple rind and sweet white pulp in segments

manihot starch See cassava.

manioc See cassava.

manna Dried exudate from the manna-ash tamarisk tree nus ornus) Abundant in Sicily and used as a mild laxative for

(Fraxi-children; it consists of 40–60% mannitol, 10–16% mannotetrose,6–16% mannotriose, plus glucose, mucilage and fraxin This isthought to be the food eaten by the Israelites in the wilderness.Manna sugar or mannite is mannitol

manna bread A cake-like product made from crushed,sprouted wheat without yeast; said to be a recipe of the Esseneswho lived by the Dead Sea at the beginning of the Christian era

mannitol Mannite or manna sugar, a six-carbon sugar alcoholfound in beets, pumpkin, mushrooms, onions; 50–60% as sweet

as sucrose Extracted commercially from seaweed (Laminaria

spp.) or by reduction of mannose (E-421)

mannosans polysaccharides containing mannose

mannose A six-carbon (hexose) sugar found in small amounts

in legumes, manna and some gums Also called seminose andcarubinose

mannotetrose See stachyose.

manothermosonication Method of sterilisation using mild heattreatment combined with ultrasonication and moderately raisedpressure

ManucolTM Sodium alginate

MAP Modified atmosphere packaging, see packaging, modified

atmosphere

MAP kinases Mitogen-activated protein kinases – a family ofenzymes that catalyse phosphorylation of target enzymes inresponse to hormones including insulin and insulin-like growthfactor

maple syrup Sap of the north American sugar maple tree, Acer saccharum Evaporated either to syrup (63% sucrose, 1.5% invert sugar, see sugar, invert) or to dry sugar for use in

confectionery

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maple syrup urine disease A rare genetic disease affectingcatabolism of the branched-chain amino acids leucine, iso-leucine and valine, due to deficiency of branched-chain keto-acid dehydrogenase (EC 1.2.4.4), leading to accumulation of highconcentrations of these amino acids and their keto-acids inplasma and urine The keto-acids give the urine a characteristicsmell like that of maple syrup If untreated, leads to severemental retardation and death in infancy.

marasmic kwashiorkor The most severe form of protein–energymalnutrition in children, with weight for height less than 60% of that expected and the oedema and other signs of kwashiorkor

marasmus See protein–energy malnutrition.

marc (1) French; spirit distilled from the fermented residue ofgrape skins, stalks and seeds after the grapes have been pres-sed for wine making The same as grappa (Italian), bagaciera(Portugal) and aguardiente (Spain) Often a harsh raw spirit,drunk young, although some are matured and smooth

(2) Insoluble residue after extraction of soluble material fromsugar beet; mainly non-starch polysaccharides, used as live-stock feed

margarine (butterine, lardine, oleomargarine) Emulsion of about80% vegetable, animal and/or marine fats and 20% water, ori-ginally made as a substitute for butter Usually contains emulsi-fiers, antispattering agents, colours, vitamins A and D (sometimesE) and preservatives

Ordinary margarines contain roughly equal proportions of saturated, mono-unsaturated and polyunsaturated fatty acids;special soft varieties are rich in polyunsaturated fatty acids Low-fat spreads are made with 10–60% fat and correspondinglyhigher contents of air and water and less energy, and generallycannot legally be called margarine

Kosher (and vegetarian) margarine is made only from vegetable oils, because ordinary margarine may include animalfats It is fortified with carotene (which is derived from vegetablesources) as the source of vitamin A, instead of retinol (which may

be obtained from non-kosher sources)

mariculture aquaculture in saline environments

marigold Pot or common marigold (Calendula officinalis); petals

are used as flavouring and colouring, sometimes as a substitutefor saffron

marinade Mixture of oil with wine, lemon juice or vinegar and herbs in which meat or fish is soaked before cooking,both to give flavour and to make it more tender Hence to marinate

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marine biotoxins Toxins in shellfish and marine fish, either duced naturally or accumulated by the fish from their diet(includes ciguatera and paralytic shellfish poisoning).

pro-marine oils See fish oils.

marjoram Dried leaves of a number of aromatic plants of ferent species, used as seasoning The most widely accepted

dif-marjoram herbs are the perennial bush Origanum majorana and the annual sweet marjoram Majorana hortensis Spanish wild marjoram is Thymus mastichina.

marker gene A readily detectable gene (e.g conferring antibiotic

or herbicide resistance) transferred into a transgenic organismtogether with the gene of interest, to permit ready identification

of those cells in which the gene transfer has been achieved.Unlike a reporter gene, it confers a survival advantage on thetransfected cells when they are grown in the presence of theantibiotic or herbicide

marmalade Defined by EU Directive as jam made from citruspeel; what was known as ginger marmalade is now known as

ginger preserve The name comes from the Portuguese lada, the quince, which was used to make preserves Used in

marma-French and German to mean jam or preserve in general

marmite (1) The original form of pressure cooker used by Papin

in 1681; it was an iron pot with a sealing lid

(2) Cookery term for a stock, or the pot in which stock is prepared

MarmiteTM Yeast extract flavoured with vegetable extract

marron glacé Chestnuts preserved in syrup; semi-crystallised

marrow (1) Bone marrow; tissue within internal cavities ofbones Red marrow is the site of formation of red blood cells

In infants almost all of the marrow is red, and is graduallyreplaced by fat (yellow marrow) in the limb bones

(2) Varieties of the gourd Cucurbita pepo.

Composition/100 g: (edible portion 87%) water 92.7 g, 88 kJ (21 kcal), protein 2.7 g, fat 0.4 g, carbohydrate 3.1 g, fibre 1.1 g, ash

See also courgette; pumpkin; squash.

marshmallow Soft sweetmeat made from an aerated mixture ofgelatine or egg albumin with sugar or starch syrup nougat isharder, containing less water, and usually incorporates dried fruit

and nuts Originally, the root of the marshmallow plant (Althaea

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officinalis), which contains mucilage as well as starch and sugar,

See also stevioside; rebaudioside.

marzipan See almond paste.

MAS Modified atmosphere storage See packaging, modified

mash tun Vessel used for mashing

maslin, mashum (1) Old term, still used in Scotland, for mixedcrop of beans and oats used as cattle food

(2) In Yorkshire and N England, a mixed crop of 2–3 parts ofwheat and 1 part of rye, used for making bread

(3) Also mesclin, miscellin; Medieval English; bread madefrom mixed wheat and rye

Mason jar Screw-topped glass jar for home bottling; patented1858

massecuite The mixture of sugar crystals and syrup (motherliquor) obtained during the crystallisation stage of sugar refining

mast See milk, fermented.

mastic (mastic gum) Resin from the evergreen shrub Pistacia lenticus and related species, with a flavour similar to liquorice,

used in Greek and Balkan cookery

mastication Chewing, grinding and tearing food with the teethwhile it becomes mixed with saliva

matai Chinese water chestnut, see chestnut.

maté Also yerba maté, or Paraguay or Brazilian tea Infusion of

the dried leaves of Ilex paraguayensis.

matjes herring Dutch; young herring caught in spring, lightlysalted and stored in barrels for a short time to allow fermenta-tion to occur

matoké Steamed green banana or plantain

matrix Gla protein See osteocalcin.

matsutake Edible wild fungus, Tricholoma matsutake, widely collected in Japan and exported canned or dried See

mushrooms

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Matzka process A low-temperature sterilisation process used forfruit juices by adding silver salts; in the presence of silver ionsthe pasteurisation temperature is only 8–11 °C The katadynprocess employs silver ions alone.

See also oligodynamic.

matzo, motza (plural matzoth) Unleavened bread or Passoverbread made as thin, flat, round or square water biscuits, and,according to the injunction in Exodus, eaten by Jews during theeight days of Passover in place of leavened bread

maw Fourth stomach of the ruminant

mawseed See poppy seed.

MaxEPATM A standardised mixture of fish oils, rich in chain polyunsaturated fatty acids: eicosapentaenoic (EPA,C20:5 ω3) and docosohexaenoic (DHA, C22:6 ω3) acids

long-mayonnaise A salad dressing, reputedly invented by the duke

of Richelieu in 1757, and originally named mahonnaise to brate the French victory at Mahon

cele-maysin Coagulable globulin protein in maize

mazindol Anorectic (appetite suppressing, see appetite control)

drug formerly used in the treatment of obesity

mazun See milk, fermented.

mazzard See gean.

McGovern committee USA; Senate Select Committee on tion and Human Needs; published Dietary Goals for the UnitedStates, first draft 1977, final version 1980, based on the proposi-tion that people should eat less of harmful foods rather thanmore of foods that are good for them The basis of most currentguidelines on healthy eating

Nutri-MCT See medium chain triglycerides.

mcv See mean cell volume.

MDM Mechanically deboned meat, see meat, mechanically

recovered

mead A traditional wine made by fermentation of honey, times flavoured with herbs and spices One of the most ancient

some-of alcoholic drinks

mealie(s) See maize.

mealie rice See maize rice.

mean cell volume (mcv) Average size of red blood cells,determined using an electronic counter which sorts by size, orcalculated from the haematocrit and red cell count/L of blood.Low values occur with severe iron deficiency (microcyticanaemia) and high values in folic acid and vitamin b12deficiency(megaloblastic anaemia)

meat Generally refers to the muscle tissue of animal or bird,other parts being termed offal or organ meat Legally defined300

in UK as all that is found between the skin and bone of theanimal.

meat bar Dehydrated cooked meat and fat; a modern form

of pemmican; 50% protein and 40% fat; provides 560 kcal (2350 kJ)/100 g

meat conditioning After an animal has been slaughtered, muscleglycogen breaks down and is metabolised to lactic acid, whichtends to improve the texture and keeping qualities of the meat.Meat that has been left until these changes have occurred is ‘con-ditioned’ Electrical stimulation of muscles is sometimes used tohasten the development of rigor mortis, and shorten the timerequired for conditioning the meat

See also meat, dfd.

meat, curing Pickling with the aid of sodium chloride (salt),sodium nitrate (saltpetre) and sodium nitrite, which permits thegrowth of only salt-tolerant bacteria and inhibits the growth of

Clostridium botulinum The nitrite is the effective preserving

agent and the nitrate is converted into nitrite during the picklingprocess The red colour of cured meat is due to the formation ofnitrosomyoglobin from myoglobin

meat, DFD Dark, firm, dry; the condition of meat when the phremains high through lack of glycogen (which would formlactic acid) It poses a microbiological hazard

See also meat conditioning; rigor mortis.

meat extender Vegetable proteins added to meat products toreplace part of the meat

meat extract The water-soluble part of meat that is mainlyresponsible for its flavour Commercially is made during themanufacture of corned beef; chopped meat is immersed inboiling water, when the water-soluble extractives are partiallyleached out and concentrated Rich in the B vitamins (particu-larly vitamins B1, B12and niacin), meat bases and potassium, and

a potent stimulator of gastric secretion

meat factor Factor used to calculate the fat-free meat content ofsausages and similar meat products, from a nitrogen estimation

meat, mechanically recovered Residual meat recovered frombones that have already been trimmed by knife Also known asmechanically deboned meat and (in the USA) mechanically sepa-rated meat It consists of meat and fat that were on the bone, com-minuted by forcing through perforated filters (Paoli, Beehive,Bibun machines) or channels (Protecon machines),as well as bonefragments, depending on the pressure used in recovery

meat, reformed Comminuted, flaked or ground meat that hasbeen bound and shaped to resemble a cut of whole meat In the

UK even if it resembles a steak, it may not be so-called

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meat speciation Identification of species of animal from whichthe meat originated.

meat sugar Obsolete name for inositol

meat, water binding capacity (WBC) The capacity of a piece ofmeat to retain added water during cutting, pressing or heating

See also meat, water holding capacity.

meat, water holding capacity (WHC) The capacity of a piece ofmeat to retain its own water content during cutting, pressing orheating

See also meat, water binding capacity.

medical foods Legal definition (in the USA) of foods formulatedfor dietary treatment of a disease, to be administered enterally(i.e by mouth or by naso-gastric tube, as opposed to parenteralnutrition), under supervision of a physician; sometimes known asenteral foods

medicinal paraffin Liquid paraffin, a mineral oil of no nutritivevalue since it is not affected by digestive enzymes and passesthrough the intestine unchanged Used as a laxative because ofits lubricant properties Formerly used to coat dried fruit

medium chain triglycerides triglycerides containing chain (8–10 carbon) fatty acids used in treatment of malab-sorption; they are absorbed more rapidly than conventional fats,and the products of their digestion are transported to the liver,rather than in chylomicrons

medium-medlar The fruit of Mespilus germanica Can be eaten fresh from

tree in Mediterranean areas but in colder climates, as the UK,does not become palatable until it is half rotten (bletted).Japanese medlar is the loquat

Meeh formula See body surface area.

megaloblast Abnormal form of any of the cells that are sors of red blood cells; they occur in bone marrow in anaemiadue to deficiency of folic acid or vitamin b12

precur-megavitamin therapy Treatment of diseases with very high doses

of vitamins, several hundred-fold higher than reference intakes.Little or no evidence of efficacy; vitamins a, d, b6and niacin areknown to be toxic at high levels of intake

megrim flatfish, the British smooth sole or scaldfish, Psetta arnoglossa.

mejing See monosodium glutamate.

mekabu Japanese; lobe leaf seaweed, normally dried

melaena Tarry black faeces due to partly digested blood as aresult of bleeding into the gut

melalgia, nutritional See burning foot syndrome.

melampyrin See dulcitol.

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melangeur Mixing vessel consisting of rollers riding on a rotatinghorizontal bed Used to mix substances of pasty consistency(hence melangeuring).

melanin Brown pigments formed when phenolic compounds incut fruit and vegetable are exposed to air and oxidise; also thepigments of skin and hair, formed from tyrosine

melano See kiwano.

melanocortin Peptide hormone that regulates melanin synthesis

in skin and hair, and also feeding behaviour through receptors

in the hypothalamus The agouti gene product antagonisesmelanocortin receptors, leading to obesity and insulin resis-

tance in mutant mice (see agouti mouse).

melba Peach poached in vanilla syrup, set in vanilla ice-creamwith a purée of raspberries Created by Escoffier, 1892, in honour

of Dame Nellie Melba

melegueta pepper See pepper, melegueta.

melezitose Trisaccharide, glucosyl-glucosyl-fructose, hydrolysed

to glucose plus the disaccharide turanose (fructose)

α-1,3-glucosyl-melibiose A disaccharide,α-1,6-galactosyl-glucose

melissopalynology Analysis of pollens present in honey, in order

to determine its botanical and geographical origin

melitose, melitriose See raffinose.

mellorine US term for ice cream made from non-butter fat

melon Gourds, sweet fruit of Cucumis melo.

Cantaloupe, composition/100 g: (edible portion 51%) water90.2 g, 142 kJ (34 kcal), protein 0.8 g, fat 0.2 g, carbohydrate 8.2 g(7.9 g sugars), fibre 0.9 g, ash 0.6 g, Ca 9 mg, Fe 0.2 mg, Mg 12 mg,

P 15 mg, K 267 mg, Na 16 mg, Zn 0.2 mg, Se 0.4µg, vitamin A

169µg RE (2063µg carotenoids), E 0.1mg, K 2.5mg, B10.04 mg,

B20.02 mg, niacin 0.7 mg, B60.07 mg, folate 21µg, pantothenate0.1 mg, C 37 mg A 230 g serving is a good source of folate, a richsource of vitamin A, C

Honeydew, composition/100 g: (edible portion 46%) water89.8 g, 151 kJ (36 kcal), protein 0.5 g, fat 0.1 g, carbohydrate 9.1 g(8.1 g sugars), fibre 0.8 g, ash 0.4 g, Ca 6 mg, Fe 0.2 mg, Mg 10 mg,

P 11 mg, K 228 mg, Na 18 mg, Zn 0.1 mg, Se 0.7µg, vitamin A 3µg

RE (57µg carotenoids), K 2.9mg, B10.04 mg, B20.01 mg, niacin0.4 mg, B60.09 mg, folate 19µg, pantothenate 0.2mg, C 18mg A

230 g serving is a good source of folate, a rich source of vitaminC

melon, jelly (or horned) See kiwano.

melting point The temperature at which a compound melts to aliquid Often characteristic of a particular chemical and used as

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a means of identification, and as an index of purity, since rities lower the melting point.

impu-melts See spleen.

membrane concentration Process of removing water, and somesolutes, by use of a semipermeable membrane It requires lessheat than evaporation, so has less effect on flavour and texture

membrane, semipermeable (selectively permeable) One thatallows the passage of small molecules but not large ones; e.g.pig’s bladder is permeable to water but not salt; collodion is permeable to salt but not protein molecules

See also dialysis; osmosis; ultrafiltration.

menadione, menadiol Synthetic vitamin k analogue (vitamin

K3, sometimes known as menaquinone-0) Formerly used in prophylaxis of haemorrhagic disease of the newborn, but its use has declined since it was shown to support redox cycling reactions and may be associated with later development ofcancers

menaquinones Bacterial metabolites with vitamin k activity;vitamin K2

menarche The initiation of menstruation in adolescent girls, mally occurring between the ages of 11 and 15 The age at menar-che has become younger in western countries, possibly associatedwith a better general standard of nutrition, and is later in lessdeveloped countries

nor-menhaden Oily fish, Brevoortia patronus, B tyrannus, from Gulf

of Mexico and Atlantic seaboard of the USA, a rich source

of fish oils Menhaden oil is 33% saturated, 29% unsaturated, 37% polyunsaturated, contains 521 mg cholesterol/

mono-100 g

Menke’s syndrome A genetic disease involving failure of theintestinal copper transport mechanism, resulting in functionalcopper deficiency Because of the effects on hair colour andstructure, sometimes known as Menke’s kinky or steely hair syndrome

merguez North African; spiced sausage made from goat ormutton, flavoured with hrisa, a mixture of pepper and cumin

mescal See tequila.

mesocarp See albedo.

meso-inositol See inositol.

mesomorph Description given to a well-covered individual withwell-developed muscles

See also ectomorph; endomorph.

mesophiles Pathogenic micro-organisms that grow best at peratures between 25 and 40 °C; usually will not grow below

tem-5 °C

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metabolic equivalent (MET) Unit of measurement of heat duction by the body; 1 MET = 50kcal (210kJ)/hour/m2 bodysurface area.

pro-metabolic rate Rate of utilisation of energy See basal metabolic

rate

metabolic syndrome insulin resistance, daemia, low hdl, hypertension and hyperglycaemia, associatedwith abdominal obesity, and sometimes also involving poly-cystic ovary syndrome and gout Sometimes called ‘syndromeX’ Mainly due to the metabolic effects of adipose tissuewithin the abdominal cavity (as opposed to subcutaneousadipose tissue) Commonly progresses to type II diabetes melli-tus when the capacity of the β-islet cells of the pancreas tosecrete insulin in response to persistent hyperglycaemia isexhausted

hypertriglyceri-metabolic weight energy expenditure and basal metabolic ratedepend on the amount of metabolically active tissue in the body,not the total body weight; body weight to the power of 0.75 isoften used to estimate metabolically active tissue

metabolism The processes of interconversion of chemical pounds in the body Anabolism is the process of forming largerand more complex compounds, commonly linked to the utilisa-tion of metabolic energy Catabolism is the process of breakingdown larger molecules to smaller ones, commonly oxidationreactions linked to release of energy

com-metabolomics Measurement of all the small molecules lites) present in the organism, which represent interactions of the

(metabo-genome, transcriptome and proteome with the environment See also proteomics; transcriptomics.

metabonomics Alternative term for metabolomics

metallisation See metallised films.

metallised films For food packaging, manufactured by applyingvery thin layers of aluminium to a plastic film by vacuum depo-sition, to improve the barrier properties of the plastic The thick-ness of the metal deposit is generally expressed as percentagelight transmission through the film

metalloproteins Proteins containing a metal For example,haemoglobin, cytochromes, peroxidase, ferritin and siderophilinall contain iron; many enzymes contain copper, manganese orzinc as a prosthetic group

metallothionein A small protein (Mr6800, 61 amino acids) thatbinds zinc, copper and cadmium Important in both absorptionand metabolism of essential metal ions, and also sequestrationand excretion of metals such as cadmium Plasma concentrationmay provide an index of zinc status

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metaphysis Growing portion of a long bone, between the physis and the shaft (diaphysis).

epi-metaproteins Products of the action of dilute acid or alkali onproteins; they are no longer soluble at their isoelectric points

(see isoelectric focusing) but will dissolve in weak acid or

alkali

metformin See hypoglycaemic agents.

methaemoglobin Oxidised haemoglobin (unlike bin in which oxygen is reversibly bound without oxidising theiron); cannot transport oxygen Present in small quantities innormal blood, increased after certain drugs and after smoking,and in babies after consumption of food or water containingmoderately high levels of nitrates Rarely occurs as a geneticdisease, methaemoglobinaemia

oxyhaemoglo-methaglen (metheglin) A traditional British wine made fromhoney (and thus a form of mead) to which herbs are addedbefore fermentation Originally for medicinal purposes

methanogens archaea found in rumen flora that producemethane (and hydrogen) as a metabolic end-product

methanol (methyl alcohol, wood alcohol) The first member of thealcohol series, chemically CH3—OH It is a highly toxic substanceand leads to mental disturbance, blindness and death when con-

sumed over a period See alcohol, denatured.

methionine An essential amino acid, abbr Met (M), Mr149.2, pKa

2.13, 9.28, codon AUG One of the three containing sulphur.Cystine and cysteine (the other two sulphur amino acids) arenot essential, but can only be made from methionine, and there-fore the requirement for methionine is lower if there is an ade-quate intake of cyst(e)ine Therefore the total sulphur amino acidcontent of foods is generally considered

methionine load test For vitamin b6 status; measurement ofurinary excretion of homocysteine after a test dose of 3 g ofmethionine; the enzyme cystathionine synthetase (EC 4.2.1.22)

UK in 1955

MethocelTM Methyl cellulose

méthode champenoise Sparkling wine made by a second fermentation in the bottle, as for champagne, but outside theChampagne region of north-eastern France

MethofasTM Methyl hydroxypropyl cellulose

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