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Chuyên ngành Food Technology
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Natamycin One of the polyene antibiotics with an-tifungal activity, this one used in preservatives for foods such as dry sausages and cheese.. Natural flavourings Flavour compounds, al

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N2 Chemical symbol for nitrogen gas

Na Chemical symbol for sodium.

NAA Abbreviation for the analytical technique

neu-tron activation analysis and the auxin

naphtha-leneacetic acid.

NaCl Chemical formula for sodium chloride.

NAD(P) Abbreviation for nicotinamide adenine

dinucleotide (phosphate).

Naegleria Genus of amoebae of the family

Vahl-kampfiidae Occur in damp soil, mud, water and

sew-age Pathogenic to humans and animals Naegleria

fowleri, a water contaminant, is the causative agent of

meningoencephalitis in humans

NAFTA Abbreviation for North American Free

Trade Agreement.

Nalidixic acid Quinolone antibiotic that exhibits

an-tibacterial activity against various Gram negative

bacteria Used in poultry production and

aquacul-ture.

Nan Flat bread originating from northwest India made

from white flour, leavened with sodium

bicarbon-ate and baked in a tandoor

Nanofiltration Form of filtration that uses

semi-permeable membranes of pore size 0.001-0.1 ȝm to

separate different fluids or ions, removing materials

having molecular weights in the order of 300-1000 Da

Nanofiltration is most commonly used to separate

solu-tions that have a mixture of desirable and undesirable

components An example of this is the

concentra-tion of corn syrups Nanofiltraconcentra-tion is capable of

re-moving ions that contribute significantly to osmotic

pressure, and this allows separation at pressures

that are lower than those needed for reverse

osmo-sis.

Nanotechnology A field of science which in its

broadest sense covers development of materials and

devices of nanometer-scale (1-100 nm)

Nanotechnol-ogy applications of relevance to the food industry

in-clude: carbon nanotubes used in construction of

bio-sensors and as adsorbents in solid phase

mi-croextraction; structured colloids and emulsions

for encapsulation of food ingredients; and

nano-composites used in food packaging.

NaOH Chemical formula for sodium hydroxide Naphthalene Aromatic hydrocarbon with a distinctive

coal tar-like odour Used as an insecticide and in the

synthesis of dyes.

Naphthaleneacetic acid A synthetic member of the auxins group of plant growth regulators,

chemi-cal name 2-(1-naphthyl)acetic acid Used as a rooting agent, in plant tissue culture and to regulate the yield

and quality of various fruits and vegetables.

Naphthol Phenol that is a major metabolite of the

insecticide carbaryl.

2-(1-Naphthyl)acetic acid Chemical name for the plant growth regulator naphthaleneacetic acid Naphthylmethylcarbamate Alternative term for the insecticide carbaryl.

Napins Storage proteins of rapeseeds (Brassica

napus).

Naranjilla Orange fruits with green-yellow flesh

pro-duced by Solanum quitoense or S angulatum The

juicy pulp is used in beverages and sherbet Also eaten out of hand, and used as an ingredient in des-serts, jellies and marmalades Rich in vitamin A and vitamin C Alternative term for lulo and quito

oranges

Narazuke Vegetables pickled in sake lees Origi-nally made from uri, a cross between cucumbers and melons, but now made using aubergines, small melons, radishes and cucumbers

Naringenin Non-bitter flavanone found mainly in

citrus fruits, but also in other fruits, e.g tomatoes Naringin Bitter glycoside present in citrus fruits Naringinases Commercial crude fungal enzyme

preparations consisting of Į-L -rhamnosidases and ȕ-glucosidases Used to degrade naringin, a bitter flavonoid found in citrus fruits, during extraction of fruit juices in order to reduce bitterness to

accept-able levels

Narirutin One of the flavanones found mainly in

citrus fruits Also known as naringenin

7-O-rutinoside Has antioxidative activity.

Nata Thick, white, mucilaginous mat formed by

fer-mentation of Gluconacetobacter xylinus grown

on the surface of coconut water, coconut milk or

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other sugary fruit juices Used in production of

des-serts, including nata de coco which is popular in the

Philippines

Natamycin One of the polyene antibiotics with

an-tifungal activity, this one used in preservatives for

foods such as dry sausages and cheese Exhibits

no antibacterial activity, so does not disturb natural

ripening processes in these foods Also known as

pi-maricin

Natto Traditional Japanese product made by

fermen-tation of soybeans with Bacillus subtilis (B.

natto).

Natural colorants Colorants that exist in nature

Natural flavourings Flavour compounds, also

essential oils, extracts and hydrolysates containing

flavour compounds, that are derived from natural

sources, such as plants, animal foods and edible yeasts

Usually they have little or no nutritive value but are

used solely to impart flavour.

Natural foods Foods produced using natural farming

techniques (e.g organic foods) and subjected to

minimal processing Free from artificial

ingredi-ents

Natural sweeteners Sweet-tasting substances that

occur in nature Saccharides, such as sucrose (sugar),

D-glucose (dextrose) and fructose (laevulose) are

the major natural sweeteners used by the food

indus-try Other natural sweeteners include sweet-tasting

pro-teins (e.g thaumatin), terpenoids (e.g

glycyr-rhizin), steroidal saponins (e.g polypodoside A),

dihydroisocoumarins (e.g phyllodulcin) and

flavon-oids (e.g neohesperidin).

Navy beans Type of common beans (Phaseolus

vulgaris).

N compounds Compounds that contain the element

nitrogen.

NDGA Abbreviation for nordihydroguaiaretic

acid.

Near infrared Infrared radiation which has a

wave-length between 0.7 and 2.5 ȝm Near infrared

(com-monly abbreviated to NIR) is subdivided into very near

infrared (0.7-1 ȝm) and short wave infrared (1.0-2.5

ȝm)

Nectarines Fruits produced by Prunus persica var

nectarina Similar to peaches in composition and

flavour, but with a smoother skin and richer colour.

Sweet, juicy flesh varies in colour from white to

yel-low, depending on variety Varieties also differ in

stone tenacity (clingstone or freestone) Rich in

vita-min A, vitavita-min C and potassium Eaten out of

hand or in salads, and used as a garnish, in toppings

and in various desserts.

Neem Common name for Azadirachta indica, a tree

native to tropical Asia Neem plants contain various

bioactive compounds and thus have been used tra-ditionally as medicinal plants Neem seed oils, seed cake and, to a lesser extent, leaf extracts can act as in-secticides and are used for preventing infestation

of stored grain and vegetables The antimicrobial activity of neem extracts may be exploited for con-trolling post-harvest spoilage of fruits and

vegeta-bles

Nematocides Pesticides used for control of nema-todes that parasitize animals or infest crops Gener-ally fall into two major classes, fumigants and

non-fumigants (contact), based on chemical and physical characteristics Commonly used examples include

methyl bromide and oxamyl.

Nematodes Group of worms which are members of

the phylum Nematoda Occur in soil, and fresh and

marine waters Some are parasites of humans,

ani-mals and plants

Neocallimastix Genus of anaerobic fungi of the

Neocallimastigaceae family Grow on a range of

sim-ple and comsim-plex carbohydrates in the rumen of

animals Species (e.g Neocallimastix patriciarum and

N frontalis) are used in the production of enzymes

(e.g xylan degrading enzymes and cellulases) Neohesperidin Flavonoid glycoside bitter

com-pounds present in bitter oranges (Citrus auran-tium) Exhibit poor water solubility, and are

impor-tant flavour compounds in orange juices The

sugar component is a disaccharide, ȕ-neohesperidose

(2-O-alpha-L-rhamnopyranosyl-ȕ-D-glucopyranose) Used as the raw material for manufacture of the

sweet-ener neohesperidin dihydrochalcone.

Neohesperidin dihydrochalcone Artificial sweeteners derived by hydrogenation of neo-hesperidin 1500-1800 times sweeter than sucrose

and stable in crystalline form, in solutions and at high

temperatures Possess a very light aftertaste and have

a short delay to reach maximum sweetness

percep-tion Have a synergistic sweetening effect when

com-bined with sugar alcohols such as xylitol and isomalt, and with other sweeteners such as aspar-tame and acesulfame K Applications include bev-erages, desserts and savoury foods Also used as flavour enhancers in a wide range of foods

Neomycin Aminoglycoside antibiotic produced by

Streptomyces fradiae Used for treatment of

coliba-cillosis in sheep, goats, swine, turkeys and cattle, with the exception of veal calves Withdrawal periods vary

with species and tolerance values are specified for kidneys, fats, livers, meat, milk and turkey skin

with fat Parenteral use in food-producing animals is not permitted in some countries

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Neopullulanases EC 3.2.1.135 Glycosidases

which hydrolyse pullulan to panose (6-Į-D

-glucosylmaltose) Useful for the production of

mal-tooligosaccharides for use in foods as prebiotics

and as non-cariogenic sweeteners Can also

hydro-lyse amyloses to maltose and catahydro-lyse

transgly-cosylation reactions

Neosartorya Genus of fungi of the family

Trichoco-maceae Neosartorya fischeri, a heat resistant species,

may be responsible for the spoilage of canned and

bottled fruits.

Neotame Trade name for one of the artificial

sweeteners, a derivative of a dipeptide composed of

the amino acids aspartic acid and

phenyla-lanine (N-(N-(3,3-dimethylbutyl)-L-Į-aspartyl)-L

-phenylalanine 1-methyl ester) Approximately

7000-10,000 times sweeter than sugar A free flowing

white crystalline powder which is water-soluble and

heat-stable, and can be used in cooking, baking and

frozen foods, as well as in tabletop applications Can

be used in combination with other non-nutritive or

nu-tritive sweeteners Although similar to aspartame,

neotame is degraded differently in the human digestive

system, avoiding problems caused by the presence of

phenylalanine for people suffering from

phenylke-tonuria Also used as flavour enhancers Marketed

by The NutraSweet Company Authorized for use in

many countries worldwide

Neoxanthin One of the xanthophyll carotenoids

found in many fruits and vegetables, but

particu-larly in spinach and other green leafy vegetables.

Precursor of the plant hormone abscisic acid

In-duces apoptosis in prostate cancer cells

Nephelometry Technique used to determine the size

and concentration of cells or particles in a solution by

measuring the intensity of scattered light Light

scat-tering depends on the number and properties of the

particles in the solution

Neral Aldehyde; cis-citral Volatile flavour compound

found in plant essential oils.

Nerol Monoterpene alcohol Volatile flavour

com-pound found in many plant essential oils and

in-volved particularly in the flavour and aroma of

grapes and wines.

Neroli oils Yellowish essential oils derived from

bitter orange blossoms by steam distillation Have an

intense aroma of orange blossom

Net protein ratio Weight gain of a group of animals

(e.g rats) fed a test diet plus the weight loss of a

simi-lar group fed a protein free diet, and the total divided

by the weight of the protein consumed by the animals

on the test diet

Net protein utilization Commonly abbreviated to NPU An index of the nutritional values of pro-teins This quality ratio indicates the amount of

die-tary protein retained in the body under specific clinical conditions Changes in body nitrogen levels following consumption of a dietary protein are compared with those following consumption of a protein-free diet for the same duration, and then the dietary nitrogen re-tained in the body is expressed as a proportion of ni-trogen intake

Nettings Nettings made with rubber thread which are used to enclose joints of meat, such as beef and ham, to prevent their disintegration during cooking.

Health concerns are associated with possible formation

of nitrosamines from vulcanizing agents used in

formulating the rubber

Nettles Plants of the genus Urtica, including stinging

or common nettles (U dioica) and small nettles (U

urens) Leaves are rich in vitamin C and can be used

as a vegetable when young Also used in herbal

prepa-rations and soups, and to make beer, wines and teas.

Neural networks Systems of computer programs and

data structures which are modelled on the human nerv-ous system and brain Incorporate large numbers of processors operating in parallel, each with an individ-ual sphere of knowledge which has been fed into it along with rules about relationships Networks can use this information to recognize patterns in large amounts

of data Used in the food industry to model processes and predict the behaviour of foods under specific

con-ditions Also known as artificial neural networks Neural tube defects Congenital malformations of

the spinal cord caused by the folds of the ectodermal neural plate failing to close properly in early embry-onic development Failures to close at the top result in anencephaly, which is always fatal; failures to close along the spine result in spina bifida, which can have either a reasonably hopeful or a very poor prognosis depending on location and other characteristics of the

opening Supplements of folic acid begun before

con-ception reduce the risk of neural tube defects develop-ing in the fetus

Neurodegenerative diseases Diseases

character-ized by the degeneration of nerve cells (neurons) in the

central nervous system Includes Alzheimer's dis-ease, dementia, Parkinson's disease and Creutzfeldt-Jakob disease.

Neurological shellfish poisoning Food poison-ing associated with consumption of shellfish con-taining neurotoxins produced by the dinoflagellate

algae Pytchodiscus brevis Gastrointestinal and

neuro-logical symptoms normally occur within 3 to 6 hours

of ingestion of contaminated shellfish

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Neurospora Genus of fungi of the family

Sordari-aceae Neurospora spp are responsible for spoilage

of bread N intermedia is used as a starter for

ont-jom and in the fermentation of bongkrek N.

crassa is industrially important for production of

en-zymes.

Neurotoxicity Property of being toxic to nervous

system tissues

Neurotoxins Toxins that act specifically or primarily

on nervous system tissues (e.g botulotoxins and

saxitoxin).

Neutralization Process of making something

chemi-cally neutral, with a pH of approximately 7

Neutron activation analysis Analytical technique

in which samples are irradiated with a reactor,

accel-erator or isotopic neutron source Radioactive nuclides

are produced by the addition of neutrons to nuclei of

specific atoms and these nuclei release energy in the

form of gamma rays or electrons to convert back to a

stable state The radiation detected is a measure of the

energy of the nuclides produced in the sample

Com-monly abbreviated to NAA

NH3 Chemical formula for ammonia.

Niacin A member of the vitamin B group Generic

descriptor for two compounds in foods which have the

biological activity of the vitamin: nicotinic acid

(pyridine 3-carboxylic acid) and nicotinamide (the

amide of nicotinic acid) The metabolic function of

niacin is in the coenzymes nicotinamide adenine

dinu-cleotide (NAD) and nicotinamide adenine dinudinu-cleotide

phosphate (NADP), which operate, often in partnership

with thiamin and riboflavin coenzymes, to produce

energy within the cells Niacin is found in animal

tis-sue as nicotinamide and in plant tistis-sues as nicotinic

acid; both forms are of equal niacin activity Rich

sources of niacin include livers, kidneys, lean meat,

poultry meat, fish, rabbit meat, cornflakes

(en-riched), nuts and peanut butter Niacin can

with-stand reasonable periods of cooking, heating and

storage Canning, drying and freezing result in

little destruction of the vitamin In cereals, niacin is

largely present as niacytin, which is not biologically

available Deficiency of niacin leads to pellagra

(pho-tosensitive dermatitis), depressive psychosis and

intes-tinal disorders Previously known as vitamin PP

Niacinamide Synonym for nicotinamide.

Nicarbazin Coccidiostat used prophylactically for

prevention of intestinal and caecal coccidiosis in

chickens Not used in laying hens due to detrimental

effects on production of eggs Withdrawal periods are

specified for treated chickens

Nickel Transition element with the chemical symbol

Ni

Nicotinamide Synonym for niacinamide and nicotinic acid amide The amide form of nicotinic acid which has niacin activity as a constituent of 2 coenzymes

(nicotinamide adenine dinucleotide (NAD) and nicoti-namide adenine dinucleotide phosphate (NADP)); these coenzymes act as intermediate hydrogen carriers

in a wide variety of oxidation and reduction reactions Nicotinamide can be formed in the body from the

amino acid tryptophan; on average 60 mg of dietary

tryptophan is equivalent to 1 mg of preformed niacin

Nicotinamide adenine dinucleotide (phosphate)

A coenzyme derived from niacin; commonly

abbrevi-ated to NAD(P)

Nicotine One of the alkaloids The principal active ingredient in tobacco, and responsible for the

addic-tive properties of cigarette smoking Also found in lower quantities in foods belonging to the Solanaceae

(nightshade) family, including tomatoes, potatoes, aubergines and peppers.

Nicotinic acid A member of the vitamin B group found in plant tissues Contributes, along with nicoti-namide found in animal tissues, to niacin activity

Chemical name pyridine 3-carboxylic acid

Nicotinic acid amide Synonym for nicotinamide Nigerose Disaccharide composed of two glucose

residues linked via an Į-1,3-glycosidic bond Isomer of

maltose.

Niger seeds Seeds from the plant Guizotia abys-sinica, which is grown in India and Ethiopia as an

oil-seeds crop

Nile perch Large freshwater fish species (Lates

niloticus) widely distributed in lakes and rivers around

Central Africa; a highly valued food fish Fresh and frozen fillets are exported from Kenya, Tanzania and Uganda to markets in Europe, Israel and the USA

Nile tilapia Freshwater fish species (Oreochromis

niloticus, formerly Tilapia nilotica) of high

commer-cial importance belonging to the cichlid family (Cich-lidae) Widely distributed in rivers and lakes of Africa

and also produced by aquaculture Marketed fresh

and frozen

NIR Abbreviation for near infrared.

NIR spectroscopy Spectroscopy performed at wavelengths in the near infrared (NIR) region Nisin Polycyclic peptide bacteriocins synthesized by

Lactococcus lactis Classed as lantibiotics and

contain the unusual amino acids lanthionine,

me-thyllanthionine, didehydroalanine and

didehydroami-nobutyric acid Used as preservatives in a variety of heat processed and low pH foods, such as processed cheese, meat and meat products, fish, and canned fruits and vegetables Exhibit broad spec-trum inhibition of Gram positive bacteria including

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important foodborne pathogens and clinically

rele-vant antibiotic resistant bacteria.

Nitrates Salts of nitric acid found in many animal

and plant foods as a result of use of nitrate fertilizers,

the nitrification process in the soil, or use of sodium

nitrate or potassium nitrate food additives Health

risks are associated with conversion of nitrates into

ni-trites in the gastrointestinal tract

Contamina-tion of drinking water with nitrates from chemicals

used in agriculture is a particular concern

Nitric acid Strong acid that forms nitrates with

met-als, carbonates, hydroxides or oxides Powerful

oxidizing agent Used in digestion or extraction of

samples during analysis Commercially utilized in

pro-duction of fertilizers, explosives and dyes.

Nitric oxide Gas (chemical formula NO) produced by

reduction of nitric acid, nitrates or nitrites, or

oxidation of ammonia.

Nitrification Conversion of ammonia or other N

compounds into nitrites or nitrates.

Nitrites Salts of nitrous acid formed by reduction

of nitrates Can be oxidizing agents or reducing

agents Authorized as food additives for

preser-vation of meat and cheese Health risks are

associ-ated with formation of nitrosamines from nitrites in

the presence of amines.

Nitrofurans Antibiotics banned from use in animal

food production in many countries due to concerns that

long term exposure in humans, as a result of

consum-ing contaminated products, constitutes an increased

risk factor for developing cancer Includes

furazoli-done, nitrofurazone and nitrovin

Nitrofurazone Broad-spectrum synthetic nitrofuran

antibiotic that is banned for use in food animals in

many countries due to the potential for residues

ex-hibiting carcinogenicity to occur in edible tissues

and milk Illegal use may be indicated by the presence

of semicarbazide, a metabolite of the drug, in foods

Nitrogen Colourless and odourless gas that constitutes

approximately three-quarters of the Earth's atmosphere

by volume The common form is dinitrogen (chemical

symbol N2) Constituent of proteins, amino acids,

and many other groups of chemicals, e.g amines,

al-kaloids and purines.

Nitrogen compounds Compounds that contain the

element nitrogen.

Nitrogen dioxide Brown gas with the chemical

for-mula NO2

Nitrogen monoxide Alternative term for nitric

ox-ide.

Nitrogen solubility index One of the

physico-chemical properties Defined as the nitrogen

con-tent of an aqueous extract of a sample obtained under

standard conditions expressed as a percentage of the sample nitrogen content Particularly applied to the

characterization of proteins.

Nitrosamines Nitroso compounds with strong carcinogenicity formed by reaction of amines with nitrogen oxides or nitrites.

Nitrosation Reaction of secondary amines or alky-lureas present in ingested foods with nitrites, forming nitroso compounds, such as nitrosamines, which

may be carcinogenic Methylguanidine, a compound present in several foods, is converted to a potent mutagen after nitrosation in the stomach Can be

inhib-ited by some dietary components, such as toco-pherols and various phytochemicals.

Nitroso compounds Organic compounds

con-taining the nitroso group, many of which are

mutagens.

N-Nitrosodiethylamine Volatile nitrosamine with

mutagenic activity Found in a range of foods,

some-times as a result of indirect contamination, e.g mi-gration from rubber or packaging materials, or

as a result of formation during processing.

N-Nitrosodimethylamine Volatile nitrosamine with

mutagenic activity; commonly abbreviated to NDMA Found in a range of foods, sometimes as a result of

in-direct contamination, e.g migration from rubber

or packaging materials or as a result of formation during processing.

Nitrosomonas Genus of Gram negative bacteria

of the family Nitrosomonadaceae, occurring in soils

and water Oxidizes ammonia to nitrites The type

species, Nitrosomonas europaea, is utilized for

bio-logical nitrogen removal from waste water, includ-ing food factories effluents.

Nitroso pigments Pigments formed during curing

of meat by the reaction of nitric oxide (synthesized by conversion of nitrites used in curing agents) with metmyoglobin or myoglobin Responsible for the pink colour of cured meat.

N-Nitrosopyrrolidine Volatile nitrosamine with

mutagenic activity May be formed in a range of foods,

including bacon, during processing.

Nitrosylmyoglobin The haem pigment of nitrite-cured meat Formed by reaction of metmyoglobin with nitric oxide Contributes to the red colour of cured meat, such as ham.

Nitrous acid A weak acid with the chemical formula

HNO2 Used as a mutagen and in tests of the resistance

of bacterial spores Implicated in the formation of nitric oxide in the gastrointestinal tract.

Nitrous oxide Colourless gas with the chemical

for-mula N2O, also known as dinitrogen oxide Used as a mild anaesthetic (laughing gas)

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Nivalenol Trichothecene produced by Fusarium spp

(e.g F nivale) during growth on foods such as wheat,

rye, barley, corn and millet.

Nixtamalization Traditional process used to improve

the nutritional quality of corn Nixtamalization

in-volves cooking and steeping corn in a lime

solu-tion, washing the corn (nixtamal) and stone grinding

nixtamal to form a corn dough or masa Masa is used

to produce nixtamalized products (e.g corn tortillas,

tortilla chips, corn chips and taco shells).

N-Lite D Trade name (of National Starch) for a waxy

corn maltodextrin which is one of a number of fat

substitutes used in dairy products, particularly

ice cream It imparts creaminess to low fat frozen

desserts, and improves their mouthfeel and

melt-ing properties

NMR Abbreviation for nuclear magnetic

reso-nance.

NO2 Chemical formula for nitrogen dioxide.

Nocardia Genus of aerobic, rod-shaped or filamentous

Gram positive bacteria of the family Nocardiaceae

Occur in soil Some species are causative agents of

mastitis in cattle; outbreaks are uncommon,

how-ever, and have typically been reported on dairy farms

with poor hygiene and management conditions Other

species may be used in the production of

biosurfac-tants A range of Nocardia species are used in

bio-technological applications for production of a variety

of enzymes and in bioconversions.

Nocardiopsis Genus of alkalophilic bacteria of the

family Nocardiopsaceae Found in soil Type species is

Nocardiopsis dassonvillei Producers of a number of

enzymes, including proteinases, glycosidases,

pectate lyases, milk clotting enzymes and

amy-lases.

N-Oil Trade name (of National Starch) for

tapioca-derived dextrins that are used as fat substitutes in

a wide range of low fat foods Provide a creamy,

fat-like texture to foods such as salad dressings,

sauces, spreads and ice cream.

Nomilin One of the limonoids with anticarcinogenic

activity found in citrus fruits Contributes to

bitter-ness of citrus juices Can be added to foods as a

flavour compound or bittering agent

Nomograms Graphical plots in the form of line charts

which may be used to solve particular types of

equa-tions Scales for the variables involved in the formula

are presented in a way such that corresponding values

for each variable are on a straight line intersecting all

scales Thus, when values for two variables are known,

the value of a third can be read from its scale

Nonachlor Component of the organochlorine insecti-cide chlordane May accumulate in animal tissues and milk, where it persists for long periods

Nonanal Aldehyde important for the flavour and aroma of many foods

Nonanone Methyl ketone that is important for the flavour and aroma of many foods including dairy products, fruits and vegetables.

Nonenal Aldehyde important for the aroma of many foods Also involved in formation of cardboard off flavour in beer.

Nonenzymic browning Food browning process

promoted by heat treatment, which includes a wide

range of reactions, such as the Maillard reaction, caramelization, chemical oxidation of phenols and madeirization.

Noni Fruits of Morinda citrifolia which have a

pun-gent aroma when ripening Used to produce fruit juices approved as novel foods by the European

Commission Also called Indian mulberries, cheese fruit or vomit fruit

Noni juices Traditionally prepared in the Hawaian

and Tahitan islands by ageing noni fruits (Morinda

citrifolia; Indian mulberries) in closed vessels for

sev-eral weeks, prior to consumption as a cure-all folk medicine Now commercially available globally in

health beverages In vitro studies suggest they can

provide a range of health promoting effects, such as

radical scavenging activity Little clinical data

ex-ist to support such claims, but noni juice contains high

levels of fibre, vitamin C and various phytochemi-cals Pure noni juice has a bitter flavour, and

com-mercial products usually contain other ingredients,

such as grape juices.

Nono Nigerian fermented milk product

Nonreducing sugars Sugars that do not have a free

carbonyl group (ketone or aldehyde) and therefore are

not able to act as reducing agents.

Nonstarch polysaccharides Components of die-tary fibre Occur in 2 forms - insoluble and soluble Both types are found in many plant foods Thought

to provide a range of health benefits

Nonthermal processes Processing techniques that do not require heat Usually refers to food pas-teurization and sterilization treatments that do not

employ heat during processing Examples include:

high pressure processing (inactivates vegetative microorganisms); ultrasonication (inactivates vege-tative bacteria and reduces heat resistance of bacte-rial spores); high voltage electric pulse treatment (electroporation; inactivates vegetative

microorgan-isms); ionizing radiation treatment (inactivates

pathogens); high intensity light pulse treatment

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activates vegetative bacteria); and high intensity

magnetic fields processing (inactivates

microorgan-isms)

Noodles Elongated, ribbon-like pasta made with

eggs, and rice, wheat or buckwheat flour Used in

European and Oriental cuisine Often used to add bulk

to soups and stews

Nootkatone Sesquiterpene that is one of the essential

aroma compounds in grapefruit.

Noradrenaline One of the catecholamines It

pro-duces a wide range of physiological effects within

the body, including vasoconstriction, increases in heart

rate and blood pressure, and release of glucose

from energy stores These effects are part of the

fight-or-flight response that enables the body to respond to

stressful situations In animals, the release of

cate-cholamines as a result of preslaughter stress may be

associated with poor meat quality Also known as

norepinephrine

Norbixin One of the dicarboxylic carotenoid

pig-ments present in seeds of the shrub Bixa orellana.

The main water soluble component of the natural

or-ange colorant, annatto.

Nordihydroguaiaretic acid Phenolic lipid soluble

lipoxygenase inhibitor that is used mainly in

antioxi-dants for fats and oils Often abbreviated to NDGA

Norflurazon Selective pyridazinone herbicide used for

pre-emergence control of annual and perennial grasses

and broad-leaved weeds around crops, including fruits

and nuts Classified by WHO as unlikely to present

acute hazard in normal use

Norharman ȕ-Carboline formed from tryptophan

during heating Demethylated analogue of harman, its

co-mutagen

Nori Dried seaweed product obtained from red algae

in the genus Porphyra (particularly P tenera and P.

yezoensis) Popular in Japan, where it is often

con-sumed in toasted form Good source of vitamin B12,

dietary fibre and certain minerals; may possess

an-ticarcinogenicity.

Norisoprenoids C13 butene cyclohexene degradation

products formed by the cleavage of carotenoids

Im-portant aroma compounds in fruits, wines and

honeys Includes both Į- and ionones and

ȕ-damascenone.

Noroviruses Enteric viruses of the family

Caliciviridae, which cause viral gastroenteritis.

Foodborne transmission is usually associated with

con-sumption of contaminated water, molluscs or ready

to eat foods Person-to-person transmission is

possi-ble Also known as Norwalk-like viruses or small

round structured viruses.

North American Free Trade Agreement The

North American Free Trade Agreement (NAFTA) is a trilateral regional pact that calls for the gradual re-moval of tariffs and other trade barriers on most goods produced and sold in North America NAFTA, which became effective in Canada, Mexico and the USA on 1 January 1994, built upon a 1989 trade agreement be-tween the USA and Canada that eliminated or reduced many tariffs between the two countries NAFTA called for immediate elimination of duties on half of all US goods shipped to Mexico and the gradual phasing out

of other tariffs over a period of about 14 years The treaty also protected intellectual property rights and outlined the removal of restrictions on investment among the three countries Mandates for minimum wages, working conditions and environmental protec-tion were added later as a result of supplemental agreements signed in 1993

Northern blotting A method for analysing RNA.

RNA is separated by electrophoresis, transferred to a chemically reactive matrix (e.g nitrocellulose) on which it binds covalently in a pattern identical to that

on the original gel, and detected by complementary

la-belled probes (RNA or single-stranded DNA) that

hy-bridize to specific RNA sequences

Norvegia cheese Norwegian semi-hard cheese simi-lar to Gouda cheese.

Norwalk-like viruses Alternative term for norovi-ruses.

Norwalk viruses Small round structured

vi-ruses of the genus Norovirus and family

Caliciviri-dae Responsible for acute gastroenteritis in

hu-mans Transmitted by the faecal-oral route via

con-taminated water and foods (e.g shellfish and sal-ads).

Norway lobsters Marine species of lobsters

(Neph-rops novergicus) found in the North Sea, the northeast

Atlantic and the Mediterranean sea Highly valued for their flesh Marketed fresh (whole, tail meat with shell

or shelled cooked or uncooked), frozen,

semi-preserved or as a component of pastes and soups Also known as Dublin Bay prawns, langoustines and scampi.

Nostoc Genus of filamentous cyanobacteria of the

family Nostocaceae Occur naturally in damp habitats

as green to black gelatinous colonies Some species produce high levels of phycobiliproteins, making them

a potential source of natural pigments for use in

foods Several species, e.g Nostoc flagelliforme, are eaten in various countries, including China N

com-mune is rich in dietary fibre and has been used in

functional foods.

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Nougat Aerated confectionery products made with

honeys or sugar, egg whites and starch syrups.

Often contains nuts, dried fruits and/or cherries

and may be either chewy or brittle in consistency

Novagel Trade name (of FMC BioPolymer) for

lose gels consisting of microcrystalline

cellu-loses and guar gums Used as fat substitutes in a

variety of low fat foods, including salad

dress-ings, processed cheese, dairy beverages and

frozen desserts Improves the mouthfeel, opacity

and consistency of these foods

Novel foods Foods prepared using unconventional

processes (particularly genetic technology), derived

from unconventional sources or offering

non-nutritional benefits Examples include

biotechno-logically derived foods, designer foods and

medical foods.

Novobiocin Narrow-spectrum antibiotic with

anti-bacterial activity against many Gram positive

bacteria Frequently used in combination with

peni-cillins for treatment of mastitis in cattle, and to

con-trol cholera and staphylococcal infections in poultry

Withdrawal periods must be observed to ensure foods

from treated animals are safe; tolerance values are

specified for meat and milk Use in poultry producing

eggs for human consumption is not permitted

NPR Abbreviation for net protein ratio.

NPU Abbreviation for net protein utilization.

Nuclear magnetic resonance Spectroscopy

technique based on the magnetic moment of atomic

nuclei An external magnetic field will partially align

the axis of spin of spinning nuclei, but some precession

about the magnetic field will occur The precession

de-pends on the magnetic field applied and the magnetic

moment of the nucleus (dependent in turn on the

chemical state of the atom), and is specific to the type

of nucleus The precession rate, measured by emission

or absorption of applied radiofrequency, is used to give

details about the composition of the sample

Com-monly abbreviated to NMR

Nuclear power Power generated by nuclear reactors

in nuclear power plants or stations Accidents at

nu-clear power stations have caused fallout of

radiocae-sium, and radioactive contamination of growing

foods

Nucleases EC 3.1.11-EC 3.1.16 (exonucleases) and

EC 3.1.21-EC 3.1.31 (endonucleases) Esterases

that cleave the phosphodiester bonds between

nucleo-tide subunits of nucleic acids.

Nucleic acids Polymers of nucleotides in which the

3ƍ position of one nucleotide sugar is linked to the 5ƍ

position of the next by a phosphodiester bond The two

major types are DNA and RNA.

Nucleosides Compounds of purine or pyrimidine

bases with a sugar, usually ribose.

Nucleotidases EC 3.1.3.31 These phosphatases catalyse the dephosphorylation of nucleotides, form-ing nucleosides and orthophosphate Exhibit a wide

specificity for 2c, 3c and 5c-nucleotides, and also hydro-lyse glycerol phosphate and 4-nitrophenyl phosphate

Nucleotides Compounds of purine or pyrimidine bases with a sugar phosphate

Nucleotide sequences The order in which nucleo-tides are situated in nucleic acids, such as DNA and RNA molecules

Nukazuke Japanese fish product consisting of fer-mented fish (usually sardine) in rice bran-based pickles.

Nuoc-mam Fermented fish sauces produced by fermenting anchovy (or other small marine fish) in salt, flavourings and spices for long periods The resulting product is clear amber in colour Used in

Vietnamese and Thai cuisine

Nuruk Starters (comprising yeasts and other fungi) for Korean rice wines.

Nutmeg One of the spices, along with mace,

de-rived from seeds of Myristica fragrans Kernels may

be used whole, grated or ground Characteristic fla-vour compounds include Į- and ȕ-pinene, myris-ticin, camphene, dipentene and sabanene

Nutmeg oils Essential oils obtained by steam

dis-tillation of ground nutmeg (Myristica fragrans).

Used as flavourings in bakery products, syrups, beverages and sweets, for example

Nut oils Oils extracted from nuts, such as almonds, hazelnuts and walnuts Best used uncooked, as heat often destroys their delicate flavour.

Nut pastes Pastes made from nuts that are used as the base for making confectionery fillings or nut spreads.

Nut products General term referring to products de-rived or prepared solely from nuts.

Nutraceutical foods Alternative term for func-tional foods.

NutraSweet Registered brand or trade name of the low calorie sweetener aspartame.

Nutria Large, semi-aquatic, herbivorous rodents of the family Myocastoridae, also known as coypu

Nu-tria (Myocaster coypus) are found in most continents,

but originate from South America Nutria provide

meat that is low in fats and cholesterol, but

mar-kets for this product have not been successfully estab-lished

Nutrient requirements Estimated levels of nutri-ents that are required to maintain health and prevent

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diseases Nutritional needs may vary according to

age, gender, physical activity levels and state of

health Various sets of reference values have been

es-tablished to provide guidance on nutrient

recommenda-tions, including dietary reference intakes (DRI) and

dietary reference values.

Nutrients Essential dietary factors, such as vitamins,

minerals, amino acids and fatty acids, that are

required by the body but cannot be synthesized in the

body in adequate amounts to meet requirements, so

must be provided by the diet Nutrient deficiency can

cause poor growth, deformity, malfunctioning and

ste-rility A range of characteristic deficiency diseases

is recognized in humans

Nutrigenetics The study of how a person's genetic

makeup affects their response to diet or specific

nu-trients It aims to identify the effect of genetic

vari-ants on responses to nutrients and to relate this to the

risk for various diseases Has the potential to provide

a basis for personalized nutrition recommendations

based on the individual's genotype in order to

pre-vent diseases before their clinical manifestation It has

been applied in certain rare monogenic diseases, such

as phenylketonuria (PKU)

Nutrigenomics The study of how the diet or specific

nutrients interact with genes to affect health and

risk of developing various diseases Understanding

gene-nutrient interactions provides a basis for

personalized nutrition recommendations based on an

individual's genotype in order to prevent diseases

be-fore their clinical manifestation

Nutrition Science of the relationship between foods,

nutrients and health A major aspect considered is the

way by which an organism absorbs and utilizes food

components The study of nutrition involves

identifica-tion of individual nutrients that are essential for growth

and maintenance of the individual, interrelationships

among nutrients within individual organisms, and

quantitative requirements of organisms for specific

nu-trients under various environmental conditions in order

to optimize health

Nutritional assessment Assessment of the nutrient

requirements or nutritional status of a person

us-ing appropriate methods

Nutritional labelling Information appearing on la-belling or packaging of foods relating to energy and nutrients in the food The information which must or

may be given, and the format in which it must appear,

is governed by law in most countries

Nutritional status State of the body in terms of the consumption, utilization and stores of nutrients Nutritional values Indications of the potential

contri-bution that a food or food component can make

to-wards appropriate nutrition Includes measures of the

efficacy and quality of dietary constituents, such as

bioavailability and protein values, and nutritional

characteristics of foods and food components such as

calorific values and glycaemic load Nutritional values of foods may be affected by cultivation condi-tions, handling and storage practices, and proc-essing.

Nuts Fruits consisting of an edible kernel within a shell, the thickness and hardness of which varies

among types Kernels have a high fat content and are

often used as the source of nut oils They are also rich

in fibre, vitamin E, folic acid and a range of min-erals Nuts are generally available shelled or

un-shelled; shelled nuts are sold in many forms including raw, blanched, roasted and flavoured They are eaten out of hand or used in a variety of sweet and savoury

dishes Commonly consumed nuts include walnuts, pistachio nuts, pine nuts, cashew nuts and al-monds Some foods known as nuts are not true nuts, e.g Brazil nuts are really seeds and peanuts are legumes.

Nylon Family of strong, elastic polyamides

materi-als, which vary from moderately flexible to strong, tough and rigid products Can be shaped when heated into forms such as sheets, bristles and fibres Resistant

to greases and oils Used widely in food packaging applications and for the immobilization of en-zymes and microorganisms.

Nypa Genus of palms The nipa palm (Nypa fruti-cans) is the source of a sugar-containing sap

Nystose Fructooligosaccharide comprising three fruc-tose residues and a glucose residue Produced by hydrolysis of inulin or from sucrose via the action

of fructosyltransferases.

Nyufu Type of fermented tofu.

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O2 Chemical symbol for oxygen gas

O2 absorbers Abbreviation for oxygen absorbers.

Oak Hard, durable wood, usually with a distinct grain,

obtained from oak trees, which belong to the many

species within the genus Quercus Used to impart a

distinctive aroma and flavour to foods by various

methods, including smoking (e.g for meat

prod-ucts and fish), storing and/or ageing in oak barrels

(e.g for wines and spirits), and addition of oak

wood supplements or extracts The term is also used to

describe the smoky flavour and aroma characteristics

of wines and spirits aged in oak barrels

Oat bran Outer layer found under the hull of the oat

grain which forms the milling fraction

Oat fibre Indigestible material derived from oats,

which comprises both soluble fibre and insoluble

fibre Used in snack foods, bakery products and

meat extenders Consumption is reported to reduce

serum cholesterol levels

Oat flakes Whole kernels of oats that are processed

by steaming, flattening through rollers and flaking

(to retain most of their nutritional value) into quick

cooking oats Flakes are white to golden in colour

and are used in breakfast cereals, bakery

prod-ucts and for further processing into muesli.

Oat flour Ground oat grains from which their outer

layers have been removed Used as an ingredient in

bakery products and snack foods.

Oat gums Gums produced from oats that are

com-posed predominantly of (1o3)(1o4)-ȕ-D-glucan

(ȕ-glucans) Used as thickeners in foods

Oatmeal Rolled or ground oats Also refers to

por-ridge made from rolled or ground oats

Oat oils Oils extracted from oats Highly unsaturated

and containing high levels of linoleic acid.

Oatrim Trade name for fibre-rich fat substitutes

made from hydrolysed oat flour and oat bran

con-taining 5% ȕ-glucans soluble fibre Imparts a creamy

mouthfeel to a range of foods, including bakery

products, salad dressings, confectionery and

dairy products.

Oats Edible starchy grain derived from plants

belong-ing to the genus Avena, particularly A sativa, A

steri-tis and A strigosa, used as a cereal food A rich source

of vitamin B1; also rich in protein and high in fat Oat starch Starch isolated from oats.

Obesity Condition in which body wt is excessive

due to the accumulation of body fat Commonly

de-fined as a body mass index of t30 kg/m2

; in

con-trast to overweight (25-29.9 kg/m2) Associated with

increased risk of developing a range of diseases, such as cardiovascular diseases, adult-onset dia-betes and some forms of cancer Lifestyle

interven-tions to prevent or reverse obesity include adoption of

a wt loss diet, increased physical activity and/or consuming functional foods designed for this

pur-pose

Obesumbacterium Genus of strictly aerobic,

rod-shaped Gram negative bacteria of the family En-terobacteriaceae. Obesumbacterium proteus, a

common contaminant of brewers yeasts, is respon-sible for producing off odour and nitrosamines in fermenting beer worts.

Oca Common name for Oxalis tuberosa, the stem

tu-bers of which are eaten like potatoes The oxalic acid present in some cultivars can be removed by sun drying or freeze drying Also known as iribia, cuiba

and New Zealand yams

Ochratoxin A Most toxic of the known

ochratox-ins Produced by Aspergillus ochraceus and

Penicil-lium verrucosum Consumption of contaminated foods

(e.g cereals, oleaginous seeds, poultry meat, grapes, wines, pulses and green coffee) gives

rise to human exposure Potentially carcinogenic to humans, and also nephrotoxic and weakly mutagenic

Contaminated feeds have a major impact on the poultry industry, producing reduced wt gain, poor feed conversion, reduced production of eggs and poor quality of egg shells.

Ochratoxins Mycotoxins produced by certain

spe-cies of Penicillium (e.g P viridicatum) and Asper-gillus (e.g A ochraceus) during growth on foods and

feeds (e.g wheat, rye, barley, oats, corn and pea-nuts) Nephrotoxic and carcinogenic in humans and animals (e.g cattle and swine) when ingested in

con-taminated foods and feeds

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