Caballero B. (ed.) Encyclopaedia of Food Science, Food Technology and Nutrition. Ten-Volume Set

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Vitamin D

0026 Meat, apart from liver, was thought to be a poor

source of vitamin D. New analytical data for meat

and liver include significant amounts of 25-hydroxy-

cholecalciferol, assumed to have a biological activity

five times that of cholecalciferol. Previous work on

the British diet and nutrition surveys using updated

food composition data of adults and young children

has shown that, rather than contributing as little as

4% of dietary vitamin D intakes, meat and meat

products appear to provide 21 and 18%, respectively,

becoming the major contributor of natural dietary

vitamin D intakes.

Role of Meat in the Diet

0027 Meat has played a significant role in human evolu-

tion. Early herbivorous hominids did not survive,

whereas those that developed the ability to hunt

became our ancestors (Homo erectus).

0028 Anthropological research shows that the length of

the gut in primates and humans became shorter with

the introduction of animal-derived food. Smaller

quantities of food of high digestibility required rela-

tively smaller guts, characterized by simple stomachs

and proportionately long small intestines, emphasiz-

ing absorption. Furthermore, it has recently been sug-

gested that selection for relatively large brains in

humans over the last 2 million years could not have

been achieved without a move to a high-quality diet,

based on animal products, since the energy saved with

a shorter gut allowed an increase in brain mass. It is

believed that better nutrition, specifically increased

animal protein and fat intake together with improved

public health, has allowed us to move towards

attaining our genetic optimum.

0029Meat has traditionally been considered an essential

component of the diet to ensure optimal growth and

development. With a limited range of foods available

in primitive societies throughout history, meat was

important as a concentrated source of a wide range

of nutrients. With the range and abundance of

foods now available to developed societies, the nutri-

tional significance of any one food is reduced. Where

meat is excluded, the missing nutrients can be sup-

plied from a combination of other foods, and within

traditional vegetarian cultures, this appears at least

adequate. Concern arises when meat is excluded

with insufficient attention given to selecting appro-

priate combinations of foods to ensure that nutrients

are supplied in adequate quantities. There is no

doubt that in modern Western societies where less

time is devoted to planning and preparing meals,

and an increasing proportion of daily food intake is

consumed outside the home as snacks and quick

meals, the inclusion of meat in the diet minimizes

the risk of micronutrient deficiencies, especially

iron, albeit subclinical.

Meat and Health: Addressing the

Concerns

0030Traditionally, meat intake was associated with im-

proved health, but as a consequence of its association

with dietary fat, this role has been marginalized.

To assess the role played by meat, numerous studies

have compared the health status and mortality of

vegetarians with those of omnivores. Simplistic

conclusions from such work can be flawed, since

interpretation of the results must take into account

the many other influential differences between

such groups. In particular, lifestyle factors must be

tbl0009 Table 9 Nutrient content of a range of offal meats

Energy

(kJ)

Fat

(g)

Iron

(mg)

Zinc

(mg)

Vitamin A

(mg)

Vit amin D

(mg)

Vitamin B

(mg)

Cholesterol

(mg)

Folate

(mg)

Heart

Lamb, raw 500 5.6 3.6 2.0 tr N 8.0 140 2

Kidney

Lamb, raw 382 2.6 5.5 2.5 96 N 17.0 315 8

Liver

Calf, raw 437 3.4 11.5 14.2 18 800 0.3 68 370 155

Lamb, raw 575 6.2 7.5 4.0 17 300 0.5 54 430 205

Pig, raw 475 3.1 13.9 7.0 17 400 1.1 23 260 295

Brains

Lamb, boiled 529 8.8 1.4 1.4 tr tr 8 2 200 6

Ton g u e

Ox, stewed 1021 18.3 2.5 3.8 tr N 4.0 N 11

N, nutrient present in significant quantities but no reliable data on amount; tr, trace.

From Chan W, Brown J, Lee SM and Buss DH (1995) Meat, poultry and game. Supplement to McCance and Widdowson’s The Composition of Foods.

Cambridge: Royal Society of Chemistry/London: Ministry of Agriculture, Fisheries and Food.

3804 MEAT/Nutritional Value

considered: vegetarians traditionally smoke less, con-

sume less alcohol, tea, and coffee, and, being gener-

ally more health conscious, tend to exercise more.

Typically, the meat-eating groups tend to be domin-

ated by sedentary, physically inactive subjects with

little interest in diet. Since the 1950s, omnivorous

diets have been relatively high in animal protein and

fat with insufficient dietary fiber, fruit and vegetables,

such that meat intake may have acted as a marker for

a generally ‘unhealthy’ diet.

0031 Regular consumption of red meat is associated,

epidemiologically, with increased risk of coronary

heart disease (CHD), owing to its fat composition.

There is, however, a growing bank of evidence that a

healthy diet which includes lean red meat can pro-

duce positive changes in lipid biochemistry. Blood

cholesterol levels are increased by inclusion of beef

fat, not by lean beef in an otherwise low-fat diet.

Equal amounts of lean beef, chicken, and fish added

to low-fat, low-saturated-fat diets similarly reduce

plasma cholesterol and low-density lipoprotein chol-

esterol levels in hypercholesterolemic and normo-

cholesterolemic men and women.

0032 The association between the arachidonic acid con-

tent of meat and increased thrombotic tendencies

has recently been challenged. The presence of large

amounts of linoleic acid in current diets results in

plasma increases of linoleic and arachidonic acids

only, but in the absence of linoleic acid, the long-

chain n-6 and n-3 polyunsaturated fatty acids present

in lean meat can influence the plasma pool, increasing

plasma 20:3n-6, 20:4n-6, and 20:5n-3 fatty acids and

probably reducing thrombotic tendencies.

0033 Meat has been associated with various cancers,

particularly colon cancer. However, meat-eating is

strongly inversely correlated with gastric cancer,

which makes any public-health recommendations

difficult to determine, based on meat-eating alone.

Epidemiologically it is difficult to distinguish the in-

fluence of animal fat, protein, and meat.

0034 There does appear to be an independent role for

protein as a source of cooked food mutagens. Hetero-

cyclic amines produced on overcooking meat have

been shown to be carcinogenic in rats, although at

normal cooking temperatures and average cooking

times, the level of these compounds produced is not

excessive, compared with the amounts required for

carcinogenicity.

0035 Nitrates are added to meat products to prevent

microbial proliferation. However, the levels used

now are much reduced such that the nitrosocom-

pounds (NOC) produced from these additives are

present at very low levels in meat products. Contrary

to public perception, their carcinogenic potential is

likely to be minor. In humans, high-protein (meat)

diets increase fecal NOC levels, although the signifi-

cance of this for normal healthy diets remains unclear.

0036Daily consumption of green and yellow vegetables

with meat is associated with a reduced risk of cancer

at many sites, whereas daily meat consumption with

less frequent vegetable consumption has been associ-

ated with increased risk. The significance of meat’s

role as a risk factor in cancer causation remains the

subject of much debate, and results of more informa-

tive long-term cohort studies are required to elucidate

the full picture.

0037There are many paradoxes concerning the apparent

associations between meat consumption and both

CHD and cancer. Some of these are listed in

Table 10. They serve to demonstrate that the diet

and health story, at least as far as meat is concerned,

is both complex and incomplete. Two reasons for this

are, first, that meat is but one influential aspect of the

diet. Its effects are modified by other foods (e.g., fruit

and vegetables) such that the net effect may be quite

different. Second, the changing lipid composition of

meat, in response to increased knowledge of lipids in

relation to health, will continue to alter the role

played by meat in this context. Fortunately, since

most of the valuable nutrients in meat are within

the lean component, reducing the visible fat has little

bearing on its contribution to micronutrient status

(Table 11).

Hygiene and Safety Aspects

0038The wholesomeness of meat and meat products is

dependent on a variety of factors, some of which act

in the period prior to arrival of the animal or bird at

the slaughterhouse. The health status of the herd or

tbl0010Table 10 Paradoxical associations between meat and health

. Generally, in countries where meat consumption is high, intake

of protective fruit and vegetables tends to be low, and vice

versa.

. There is a lower risk of colon cancer among South Asian

immigrants to the UK, than in the general population, and this

is equally true of vegetarian and meat-eating Asians.

. Mormons who abstain from alcohol, tea, coffee, and smoking

but consume meat have death rates from cancer and CHD

similar to those of vegetarian groups, indicating that meat is

not the major determinant. Blood pressure is reduced on

switching from a meat-based diet to a vegetarian diet, but

adding meat to a vegetarian diet is not associated with an

increase in blood pressure, suggesting that the potassium-

to-sodium ratio is more influential than the presence of meat

per se.

. Consumption of meat has almost doubled in Japan since the

1970s, yet CHD morbidity has reduced from an already low

level. Meat consumption in the USA remains higher than in the

UK, yet, unlike the UK, morbidity from CHD has been falling

steadily since the 1970s.

MEAT/Nutritional Value 3805

flock is in turn influenced by the method of hus-

bandry practiced on the farm, the health prevention

measures applied, the conscientiousness of monitor-

ing, and the level of prompt and necessary action

taken, e.g., the isolation and treatment of veal calves

infected with one or more species of salmonellae.

However, calves may be carriers of infections such

as Escherichia coli and Listeria monocytogenes,and

display no symptoms of disease but may prove a

hazard to public health when meat and offal are

prepared from the carcasses. Similarly, campylobac-

teria may be present in a mild form in a batch of

broilers which appear perfectly healthy in life but

may prove a hazard to the consumer. Close monitor-

ingoffarmhealthrecordsandscrutinybytheherd/flock

veterinarian and collaboration with the supervising

official veterinary surgeon in the slaughterhouse and

poultry plant will help prevent subsequent potential

consumer health hazards.

0039 The raising of stock in dirty conditions allows the

hides, fleeces and feathers to contaminate the envir-

onment during the slaughter and dressing of car-

casses. Cross-contamination of the carcasses from

feces and soil in addition to the soiling of plant,

equipment, and the protective clothing of slaughter-

house operatives can markedly reduce the general

hygiene in the meat plant with levels of bacteria,

bacterial spores, parasites, viruses, and fungi exceed-

ing acceptable levels. Staphylococcus aureus is a

normal commensal of skin and hair, and can produce

toxins in food. A highly successful recent campaign

has highlighted the necessity for only clean livestock

to be presented for slaughter.

0040 Transport of animals, especially loading, unloading,

and lairaging, can lead to stress conditions, particu-

larly if groups are mixed. In some countries, two-tier

lorries are used to transport cattle, and three-tier

sheep transporters are common worldwide, resulting

in gross contamination with urine and feces.

Again, stress from loading and unloading can occur.

Stressed animals, particularly carriers of disease, are

known to demonstrate clinical disease and excrete

pathogenic organisms. Welfare and hygiene regula-

tions governing animals during transport minimize

such occurrences.

0041The slaughterhouse itself may not be free from

external vectors of disease – insects, vermin, and

birds must be excluded from the curtilage of the

meat plant. Measures are in place and reviewed regu-

larly so that the environment of the meat plant suffers

minimum contamination from the animals consigned

to the plant, from the lorries and staff transporting

the stock, and from all other potential vectors of

pathogenic and spoilage agents into and throughout

the plant.

0042Procedures within the meat or poultry plant itself

dictate the standard of hygiene and safety of the

product. The training and continuing professional

development of staff in handling of and caring for

the animals, in stunning and slaughter techniques,

and in the dressing procedures of the carcasses are

significant contributors to the overall standards per-

taining through the plant. The operative has the po-

tential to contaminate the carcass, and vice versa, but

training and legislation obviate this from occurring.

0043Management must be aware of the likely points of

entry of pathogenic agents and where they may have

maximum impact on the meat and meat products.

Recognition of these critical points where hazards

are potentially most dangerous is now enshrined in

the Hazard Analysis and Critical Control Point

principle. Checking regularly and acting on findings

at these areas in the meat plant allow a structured

approach to the maintenance of hygiene and safety

aspects of meat and poultry and their products. In-

creasing rates of throughput on the slaughterline must

be accompanied by even more vigilant monitoring of

hygiene standards.

tbl0011 Table 11 Nutrient variability across the carcass – values given for lowest and highest fat cuts for different species

Cut of meat Nutrients per 100 g weight

Energy (kJ) Fat (g) Vitamin D (mg) Iron (mg) Zinc (mg)

Veal escalopes, raw 445 1.7 1.3 0.6 2.4

Beef flank, lean raw 735 9.3 0.5 1.8 3.6

Beef, stewing steak, lean, raw 512 3.5 0.8 2.1 5.7

Chicken, light meat, raw 445 4.4 0.2 0.5 0.7

Chicken, leg quarter with skin, raw 811 13.3 0.5 0.8 1.4

Lamb, best end neck cutlets, 34% fat, raw 1327 27.9 0.4 1.2 3.5

Lamb leg, lean, raw 617 4.7 1.5 3.1

Pork, leg joint lean, raw 449 2.2 0.5 0.8 2.2

Pork, belly joint/slices, raw 1084 20.0 0.8 0.6 1.7

From Chan W, Brown J, Lee SM and Buss DH (1995) Meat, poultry and game. Supplement to McCance and Widdowson’s The Composition of Foods.

Cambridge: Royal Society of Chemistry/London: Ministry of Agriculture, Fisheries and Foods.

3806 MEAT/Nutritional Value

0044 The proper dressing of the carcass is fundamental

to good hygiene. The hide, fleece, or feathers consti-

tute a dirty coat to the sterile muscle and organs. The

alimentary tract extending from the mouth to the

anus is also a source of microbes and parasites. There-

fore, the exterior coat and the complete intestinal

tract must both be removed carefully so that

the absolute minimum of contamination occurs. The

surface of meat or muscle is an excellent medium on

which pathogens and spoilage organisms grow, so the

separation of edible and inedible tissues must be

carried out expertly and completely. For this reason,

the movement of these two elements follows an

agreed flow chart implicitly within the plant so that

‘clean’ and ‘dirty’ areas are entirely separate. No

crossover of staff, equipment, and tools is allowed;

however, in the case of supervising officers moving

between areas, a strict regime of changing protective

clothing must be followed.

0045 Water used within the meat plant must be of a

quality that does not present a risk to the meat or

meat product. Potable water is routinely checked in

the slaughterhouse and meat processing plant so that

pathogenic and spoilage organisms are not allowed

entry. The monitoring is supervised by the official

veterinary surgeon of the plant, as are the ante-

mortem examinations, post-mortem inspections of

the animals or birds and carcasses to check for patho-

logical change, residues of veterinary medicines, and

other substances, and the storage temperature control

for meat and meat products. In many countries, vet-

erinarians are helped in their duties by assistants/

meat-hygiene inspectors to ensure that only healthy

carcasses and their offals are deemed fit for human

consumption.

0046 These duties are delineated in national meat hy-

giene and inspection legislation, which is harmonized

throughout the European Community. Other meat-

producing countries, e.g., the USA, Australia, and

New Zealand, adhere to their own similar legislative

controls.

0047 Meat products may undergo little processing, e.g.,

steak tartare, when no cooking takes place, or under-

cooking may unwittingly allow pathogenic agents to

survive, e.g., lightly barbecued beef burgers being the

source of an outbreak of hemolytic Escherichia coli

O157. The increase in the number of chilled ready-

made meals supplementing some frozen products

may also be conducive to poisoning with organisms

or toxins surviving in the meat if proper procedures in

storage, preparation, and cooking are neglected.

0048 The integrity of properly prepared meat and

poultry and their products can be – and often is –

undermined by contamination by a food handler who

has neglected proper personal hygiene procedures or

who is a carrier of a food-poisoning organism. The

mishandler or carrier could, of course, be the con-

sumer in their own home.

0049In conclusion, therefore, the arrival of meat and

poultry and their products on the table from the farm

can be hazardous if neglect occurs at any of the steps of

the journey. Legislation, guidelines, and well-recog-

nized proven routines ensure safe and healthy prod-

ucts, provided these are properly understood and

implemented. However, one significant area of con-

cern to the consumer, in the UK in particular, is the

catastrophic bovine spongiform encephalopathy

(BSE) epidemic that has devastated the livestock and

meat industry.

0050Control measures introduced early on in the epi-

demic reduced the incidence of BSE markedly after its

peak in 1992 and 1993, although the long incubation

period (4–5 years) meant that any preventative legis-

lation took the same time for its effects to be realized.

Much research has been carried out in the UK and

around the world on BSE, with consequent benefits

accuring to other transmissible spongiform encepha-

lopathies, including scrapie in sheep and Creutzfeldt–

Jakob disease (CJD) in humans.

0051Some young consumers of beef contaminated by

the BSE agent have contracted a new variant of

CJD. However, this contamination occurred prior to

the controls introduced in the late 1980s. It will be

some years before it is known how many victims will

succumb to this new form of CJD on account of the

unknown length of the incubation period in humans.

See also: Anemia (Anaemia): Iron-deficiency Anemia;

Bioavailability of Nutrients; Carcinogens:

Carcinogenic Substances in Food: Mechanisms;

Coronary Heart Disease: Etiology and Risk Factor;

Prevention; Fatty Acids: Tr a n s -fatty Acids: Health Effects;

Iron: Physiology; Protein: Food Sources; Quality;

Selenium: Physiology; Vegetarian Diets; Zinc:

Physiology

Further Reading

Aiellio LC and Wheeler P (1995) The expensive-tissue

hypothesis. The brain and the digestive system in

human and primate evolution. Current Anthropology

36: 199–221.

Analytical Methods Committee of the Royal Society of

Chemistry and Meat and Livestock Commission

(MLC) (1991) Nitrogen factors for pork: a reassessment.

Analyst 116: 761–766.

Analytical Methods Committee of the Royal Society of

Chemistry and Meat and Livestock Commission

(MLC) (1993) Nitrogen factors for beef: a reassessment.

Analyst 118: 1217–1226.

Analytical Methods Committee of the Royal Society of

Chemistry and Meat and Livestock Commission

MEAT/Nutritional Value 3807

(MLC) (1996) Nitrogen factors for lamb. Analyst 121:

889–896.

Chan W, Brown J, Church SM and Buss DH (1996) Meat

products and meat dishes. Supplement to McCance and

Widdowson’s, The Composition of Food. Cambridge:

Royal Society of Chemistry/London: Ministry of Agri-

culture, Fisheries and Food.

Chan W, Brown J, Lee SM and Buss DH (1995) Meat,

poultry and game. Supplement to McCance and Wid-

dowson’s, The Composition of Food. Cambridge: Royal

Society of Chemistry/London: Ministry of Agriculture,

Fisheries and Food.

Denke M (1994) Role of beef and beef tallow, an enriched

source of stearic acid, in a cholesterol lowering diet.

American Journal of Clinical Nutrition 60(supplement):

1044S–1049S.

Gibson SA and Ashwell M (1997) New vitamin D values for

meat and their implications for vitamin D intake in

British adults. Proceedings of the Nutrition Society 56.

Keenan JM and Morris DH (1995) Hypercholesterolemia.

Dietary advice for patients regarding meat. Postgraduate

Medicine 98: 111–121.

Nutrition Society (1994) Symposium on ‘The role of meat

in the human diet’. Proceedings of the Nutrition Society

53: 263–333.

Scott L, Dunn JK, Pownall HJ et al. (1994) Effects of beef

and chicken consumption on plasma lipid levels in

hypercholesterolemic men. Archives of Internal Medi-

cine 154: 1261–1267.

Shi B and Spallholz JE (1994) Selenium from beef is highly

bioavailable as assessed by liver glutathione peroxidase

EC 1.11.1.9) activity and tissue selenium. British Journal

of Nutrition 72: 873–881.

Sinclair AJ, Johnson L, O’Dea E and Holman R (1994)

Diets rich in lean beef increase arachidonic acid and

long-chain n-3 polyunsaturated fatty acid levels in

plasma phospholipids. Lipids 29: 337–343.

Ulbricht TLV (1995) Fat in the Food Chain. A Report to the

Ministry of Agriculture, Fisheries and Food. Available

from MAFF Library.

Hygiene

J F Gracey, Brookvale Hornsby, Carlisle, Cumbria, UK

This article is reproduced from Encyclopaedia of Food Science,

Introduction

0001 Traditional meat inspection procedures have remained

virtually unchanged for over 100 years in many coun-

tries. They were mainly based on the work of the

German veterinarian, Robert von Ostertag, who in

1872 published his textbook Handbuch der Fleisch-

beschau fr Tiera¨rzte, Arzte und Richter, and on the

pathogenesis of bovine tuberculosis and are thus solely

concerned with postmortem gross pathology.

0002However, with the elimination of bovine tubercu-

losis and other notifiable diseases in many areas, the

change in disease type to the so-called diseases of

production, many of which are associated with out-

breaks of food poisoning, and the new systems of

intensive husbandry, especially of pigs and poultry,

attention is now beginning to be focused on the live

animal. Consumer concern about intensivism, animal

welfare, and residues in foods of all forms, has also

served to influence authorities about the safety of the

food we eat.

0003In addition, there has been concern about some of

the techniques used in meat inspection, notably the

number of routine incisions made in meat and offal,

for each incision results in varying degrees of contam-

ination. Indeed, it has been advocated by some

experts that the incision of lymph nodes should be

abandoned and replaced by inspection only. The cost-

effectiveness of traditional methods has also come

under adverse criticism, but the complete absence of

proper veterinary antemortem (AM) examination

and laboratory procedures in many quarters has

probably been the main reasons for a more scientific

approach to the inspection of meat.

0004Although public health is the main consideration,

much can also be achieved with regard to the

promotion of animal health and welfare, which also

demand attention when cost-effectiveness is under

inquiry.

Demands of the Consumer

0005The consumer demands and is entitled to the

following safeguards:

0006Meat free from all zoonotic bacterial and viral

diseases and their toxins, e.g., tuberculosis,

salmonellosis, listeriosis, campylobacteriosis, yer-

siniosis, giardiasis, vibriosis, colibacillosis, botu-

lism, and ornithosis, and also free from parasitic

diseases such as cysticercosis, trichinosis, hydati-

dosis. (See Campylobacter: Campylobacteriosis;

Listeria: Listeriosis; Parasites: Illness and Treat-

ment; Viruses; Zoonoses.)

0007Meat free from residues of drugs, hormones, anti-

biotics, heavy metals, pesticides, and tranquilizers.

(See Heavy Metal Toxicology; Pesticides and

Herbicides: Toxicology.)

0008Meat produced in a hygienic manner from live-

stock handled humanely.

0009Meat which is wholesome, palatable in flavor and

tenderness and of the nature, substance, and qual-

ity demanded.

3808 MEAT/Hygiene

Efficient Meat Inspection

0010 In order to achieve the foregoing desiderata, three

important investigations are required:

0011 AM examination of the live animal or bird with

reference to its previous husbandry.

0012 Postmortem (PM) examination of the carcass and

its viscera.

0013 Microbiological, pathological, and chemical tests,

where required.

Should any of these fundamental requirements be omit-

ted or performed at suboptimal levels, efficient meat

inspection can be said to be lacking and the consumer

possibly put at risk. While PM examination is still

required to eliminate lesions of gross pathology,

modern meat inspection must be concerned with the

nontangible agents of Salmonella, Listeria,andCam-

pylobacter which are related to the increasingly

common human foodborne diseases. The vital import-

ance of laboratory procedures is illustrated in the diag-

nosis of bovine spongiform encephalopathy (BSE).

First identified in England in 1986, the condition, be-

cause of its long incubation period, only affects adult

bovines, has a long clinical course with neurological

and behavioral symptoms, and is invariably fatal. Diag-

nosis can only be made by demonstrating spongiform

changes and the presence of scrapie-associated fibrils

(SAF) in fixed brain tissue by light microscopy. (See

Bovine Spongiform Encephalopathy (BSE).)

0014 It is necessary to remember that many conditions

can only be recognized or suspected in the live animal;

PM examination may reveal nothing or at the most

only minor lesions which are easily overlooked.

Among these are tetanus and neurological diseases

such as listeriosis, BSE, Aujeszky’s disease and rabies,

and many subclinical conditions. The bovine which

shows only slight loss of condition and mild diarrhea

may well be a case of salmonellosis, but in the absence

of significant PM findings may be passed as fit for

human consumption and in addition contaminate

other meat as well as personnel.

Legislative Authority

0015 In England and Wales, legislative authority is con-

tained in the Fresh Meat Export (Hygiene and Inspec-

tion) Regulations 1987 for export purposes; AM

inspection is not required for the home market

under the 1987 Meat Inspection Regulations. The

equivalent European Community (EC) law is the 91/

497/EC Directive which amends and consolidates

Directive 64/433/EC on health problems affecting

intra-EC trade in fresh meat to extend it to the pro-

duction and marketing of fresh meat.

0016General provisions are made concerning the time of

inspection – day of arrival at abattoir with reinspec-

tion if held overnight; facilities to be provided; need

for adherence to animal welfare rules; resting for 24 h

of tired and agitated animals; prohibition of slaughter

of animals whose meat is likely to be unfit; and a

detailed PM examination of certain categories of

diseased animals.

0017Less than one page is devoted to AM, compared

with four on PM. A further anomaly in EC law relat-

ing to AM inspection is given in the Council Regula-

tion COM(89) 668 laying down health rules for the

production and placing on the market of fresh poultry

meat, which indicates that AM inspection can be

carried out by lay assistants. One of the cardinal

rules in the diagnosis of disease, in bird or beast, is

that it be accurate, otherwise both public and animal

health may well be jeopardized. The diagnosis of

poultry disease is no less difficult and important

than that in the larger farm animals.

Legal Controls in Milk and Meat

Production

0018Apart from the Zoonoses Order 1989, which requires

the State Veterinary Service (SVS) to be notified

when Salmonella or Brucella organisms are isolated

from samples taken from farm animals and their

carcasses, products, and surroundings, and similar

legislation relating to residues, the law associated

with meat production is sparse compared with that

for milk.

0019In England and Wales the Milk and Dairies

(General) Regulations 1959 stipulate the following

requirements: premises to be of registered basic struc-

tural standards; a safe and adequate water supply;

effective hygiene and milking routines; prohibition

on the sale of milk from diseased cows, with periodic

inspections of premises and stock. In addition, the

Milk (Special Designation) Regulations 1989 require

the registration of licenced processing dairies (pas-

teurization; sterilization and ultrahigh-temperature

(UHT) milk); registration of heat treatment plants

with special reference to temperature recorders and

flow diversion valves; microbiological standards for

raw and heat-treated milk; prescribed heat-treatment

processes and special conditions of sale for untreated

milk. (See Heat Treatment: Ultra-high Temperature

(UHT) Treatments; Pasteurization: Principles; Steril-

ization of Foods.)

0020Now that the new Food Safety Act of 1990 has

defined ‘food source’ as ‘any growing crop or live

animal, bird or fish from which food is intended to

be derived (whether by harvesting, slaughtering,

milking, collecting eggs or otherwise),’ it is to be

MEAT/Hygiene 3809

expected that comparable legislation will be enacted

for meat production.

Purposes of Antemortem Inspection

0021 Since AM and PM procedures are intimately linked,

some of the following also apply to the latter:

0022 Protection of the public health against bacterial,

viral, parasitic and chemical hazards.

0023 Protection of livestock against the spread of infec-

tious diseases, especially notifiable diseases.

0024 Protection of animal and food handlers against

zoonoses.

0025 Reduction of certain conditions and injuries caus-

ing unnecessary losses in livestock through disease

data retrieval and feedback to producers.

0026 Assurance of the meat industry and the public

against meat of inferior quality, with avoidance

of wastage of a valuable commodity.

0027 Prevention of contamination of meat, premises,

equipment, and personnel by dirty animals.

0028 Efficient handling of livestock before and at slaugh-

ter to insure high standards of animal welfare and

subsequent good meat quality and shelf-life.

0029 The area of PM examination rendered more

straightforward with fewer condemnations.

0030 ‘One of the most important functions of antemor-

tem inspection is to ensure that animals are rested

sufficiently so that signs important to inspection

disposition are not masked. It also ensures that

signs that are important to inspection disposition

but that may be less readily observed (or not evi-

dent) at postmortem examination can be taken

into account in reaching a decision as to safety

and wholesomeness of meat’ (Codex Alimentarius

1991).

Preslaughter Livestock Handling

0031 Although AM inspection is usually taken to represent

the clinical examination immediately before slaughter

(AM immediatum), its full scope embraces preslaugh-

ter livestock handling and extends to the husbandry

of the animal on the farm.

0032 Factors such as the length of journey, time of year,

environmental temperature, climatic conditions, food

and water availability, species/age/sex of animal and

its source, e.g., market or farm, influence the lairage

holding time. It is important to keep farm social

groups intact, to segregate horned and aggressive

animals, to isolate the female in estrus, and the sick

or injured beast (for further examination). Young

bulls and spring lambs are best slaughtered early, as

is the cow in good condition in cold conditions since

she may succumb to hypomagnesemic tetany. Stress

is the evil which must be controlled at all costs

through efficient handling by trained stockmen.

Much can also be achieved by providing straw and

fine tepid-water sprays for pigs in lairage pens to

prevent fighting.

0033Preslaughter lairage periods can therefore vary. But

excessively long periods are contraindicated since

they can result in deaths, injuries, loss of condition,

cross contamination, difficulties in lairage cleansing,

and problems with carcass dressing, e.g., excess

ruminal/intestinal fluid in cattle.

0034To be humane to animals is to handle them in

a manner least distressing to them and with full con-

sideration for their normal species-specific behavior

requirements.

Decisions on Antemortem Inspection

0035UK and EC law in the main deal with the system

of AM inspection. The only legislation in the UK

governing the admission of animals to meat plants is

contained in the Slaughterhouses Hygiene Regula-

tions 1977 (Amendment 1987), which deal only

with casualty animals, i.e., those which are affected

with certain diseases or injuries or represent culls

from herds due to infertility or old age.

0036Since the aim of meat inspection is to produce a

safe and wholesome product for the consumer, the

conditions governing the admission of animals for

slaughter must be extremely stringent in order

that only apparently normal livestock and genuine

casualty animals are accepted.

0037The following categories of decisions constitute the

ideal rather than that specified by law:

0038Refusal or admission under special control.

0039Release for slaughter of all apparently normal

animals.

0040Delayed slaughter, e.g., because of inadequate

drug withdrawal period or temporary illness.

0041Slaughter under special circumstances, e.g., casu-

alty animals at the end of the kill or in emergency

slaughter unit.

0042Total condemnation: (a) dead, dying and disabled

animals; (b) pigs with temperatures of 41



and higher (other species > 40.6



C); (c) conditions

justifying total condemnation on PM examination;

(d) animals showing symptoms of toxic, metabolic,

nervous, or circulatory disturbance; (e) nutritional

imbalances and parasitic diseases – listeriosis,

leptospirosis, Aujeszky’s disease, tetanus, rabies,

anaplasmosis, ketosis, parturient paresis, scrapie,

BSE, grass tetany, transport tetany, strangles,

acute inflammatory lameness, extensive fistula,

3810 MEAT/Hygiene

glanders, farcy, swine fever, anthrax, and animals

which have been vaccinated with anthrax vaccine

within the previous 6 weeks.

0043 Category 5 is considered to be a most important

one since these are all casualty animals, many of

which have been certified as such by practicing veter-

inary surgeons under the Slaughterhouses Hygiene

Regulations. Although in existence in the USA and

other countries, this particular category does not yet

apply in the UK. It is, however, a most important

sector and one which should be embodied in all

meat inspection legislation. The fact that up to 50%

of such cases may ultimately be totally condemned is

not only a reflection of some standards of veterinary

certification but can also be regarded as a waste of the

time of meat plant staff, whose health on occasions is

also put in jeopardy.

0044 The information gleaned at AM inspection must be

recorded and passed to the meat inspectorate. Should

a zoonosis, e.g., ringworm or contagious pustular

dermatitis (orf), be detected, all staff – especially the

lairage personnel – must be alerted. While orf usually

occurs as a benign skin lesion on the hands and arms

of humans, there is evidence that a serious systemic

form occurs and is becoming more prevalent. Ex-

treme vigilance is necessary, therefore, especially

with casualty animals. It is not unknown for an

anthrax case to be consigned for slaughter!

Antemortem Completum Inspection

0045 It was indicated earlier that a proper examination of

the live animal must extend beyond the immediate

preslaughter clinical inspection if guarantees of food

safety and wholesomeness are to be made.

0046

The health status of the farm of origin and the husbandry

of slaughter animals have a significant effect on the

safety and wholesomeness of meat. In this respect, all

efforts should be made to collect and evaluate informa-

tion that might have influence on antemortem and post-

mortem (Codex Alimentarius October 1991).

0047The farm is, in fact, the most important hazard an-

alysis and critical control point (HACCP) in all the

meat hygiene operations which begin with animal

husbandry and end in the consumer’s home. (See

Hazard Analysis Critical Control Point.)

0048Several countries, notably The Netherlands

(pigs), New Zealand (sheep), Northern Ireland

(cattle), USA, and Canada, which are concerned

about current meat inspection systems, are enacting

schemes referred to as integrated quality control

(IQC) based on abattoir and farm disease data in

conjunction with codes of practice for livestock

producers (Figure 1). In some cases AM inspection

is carried out on the farm, and is repeated at the point

of slaughter. Especially for poultry flocks, this would

seem to be an ideal which could be easily performed

to great advantage.

0049The on-farm information which is of importance

for meat inspection purposes relates to morbidity and

mortality rates, animal welfare levels, the use of anti-

biotics, hormones, and veterinary drugs, results of

laboratory tests (microbiological, serological, and

chemical for residues), results of tests for tuberculosis

and brucellosis and type of feeding. Since one of the

main concerns of the meat hygienist is the contamin-

ation of carcass meat from filthy hides and fleeces, the

standard of farm hygiene, especially of the loose

housing of cattle, feeding of sheep on root crops and

stock during the winter months, are of vital concern.

Commenting on this important issue, which is both a

Central laboratory

Sound husbandry principles

Antemortem examination

Farm

On-farm data

Laboratory service

Antemortem examination

Meat inspection

Disease records

Central data collection

and retrieval

Healthy stock

(less stringent inspection)

Diseased/injured

stock

(additional examination

laboratory tests)

Certificate from/

report to

Practicing

veterinary surgeon

fig0001 Figure 1 Centralized meat hygiene service. After Skovgaard N (1991) Ante mortem and post mortem meat inspection. Need for

improvement. In: Hannan J and Collins JD (eds) The Scientific Basis for Harmonising Trade in Red Meat. Dublin: University College, with

permission.

MEAT/Hygiene 3811

hygiene and welfare matter because of the damage to

skin, the Richmond Committee on the Microbio-

logical Safety of Food (1991) stated that ‘farmers

can, therefore, contribute to food safety by producing

healthy, clean and unstressed animals for slaughter.’

The abattoir data which are transmitted back to the

producer for control purposes consist of the disease

and injury findings encountered in the stock at

slaughter. The practicing veterinary surgeon who sup-

plies certificates for casualty animals should receive a

report in respect of such animals.

0050 The first Farm Quality Assurance Scheme for Beef

in the UK is already under way in Northern Ireland.

At present a voluntary arrangement, it should provide

a basis for eventual legislation governing the hus-

bandry of beef cattle. Organized by the Northern

Ireland Livestock and Meat Commission (NILMC),

it has the following Code of Practice:

0051 Commitment by farmers to produce a wholesome

product with due regard to animal welfare and disease

control; 3 months’ residence on farm for all accepted

stock; feeding to be grass and vegetable protein (root

crops, brassicas, molasses, etc., may be approved);

no unlicensed growth promoters or feed additives to be

used; Department of Agriculture Code of Recommenda-

tions for Welfare of Livestock to be adopted; animals

to be kept clean and in good condition; dirty animals

ineligible for scheme; farm investigators by NILMC may

be necessary; only healthy animals, naturally produced,

to be eligible; declaration of freedom from BSE neces-

sary; veterinary record and programme of disease

control to be kept; strict use of veterinary drugs and

observance of withdrawal periods; segregation of sick,

injured and fallen animals; stress-free handling and

transport; bruised carcasses ineligible for scheme.

Future Developments

0052 AM and PM inspection procedures must always be

appropriate to the incidence and type of diseases

prevalent in the various species of the food animals.

However, a supply of clean, healthy, and residue-free

animals for slaughter can only be achieved by careful

on-farm and preslaughter inspection, due regard

having been paid to proper husbandry methods.

0053 The detection of certain parasitic diseases, e.g.,

cysticercosis, trichinosis, fascioliasis, hydatidosis,

thysanosomiasis, now only possible at PM, may well

be carried out at AM by enzyme-linked immunosor-

bent assay (ELISA) examination of blood at AM, thus

obviating the need for the current mutilating and

contaminating incisions of meat and offal.

0054 Strict veterinary certification of healthy and casu-

alty stock will also assume a dominant role in the

future by providing data for the meat inspectorate

to assist in carcass/offal judgments. Animal health

will also be promoted through feedback from PM

inspection to the farmer and the practicing veterinary

surgeon, the latter in relation to casualty and cull

animals. Refer to individual meats.

See also: Bovine Spongiform Encephalopathy (BSE);

Campylobacter: Campylobacteriosis; Hazard Analysis

Critical Control Point; Heat Treatment: Ultra-high

Temperature (UHT) Treatments; Heavy Metal

Toxicology; Legislation: Codex; Listeria: Listeriosis;

Parasites: Illness and Treatment; Pasteurization:

Principles; Pesticides and Herbicides: Toxicology;

Sterilization of Foods; Viruses; Zoonoses