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From: [e-mail] (Paul E. J. King)
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Summary: Answers to legal, science, health, and industry questions
         concerning food science. Also has a list of abbreviations of
         significance to food science. Persons wishing to post to
         sci.bio.food-science are advised to read this FAQ first.
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RE-POST: FAQ Section 3/3 - SCI.BIO.FOOD-SCIENCE Frequently-Asked Questions

See the first section (1/3) of this FAQ for any preliminary and
introductory remarks. See this section also for a list of food science
related sites and abbreviations.

For a list of definitions of industry, marketing, and scientific terms in
food science, see section 2/3 of the FAQ.

*****************************************************************************

V. FREQUENTLY ASKED QUESTIONS ABOUT FOOD SCIENCE AND TECHNOLOGY

         Here are brief answers, compiled by the Institute of Food
    Science & Technology, to some of the most frequently asked questions
    about food science and technology topics. Food scientists and
    technologists will appreciate that, because they are brief, and
    because they are intentionally written so as to be comprehensible to
    enquiring non-scientists readers of the newsgroup, they will not
    adequately fulfil the requirements of a scientist looking for a full
    "textbook" account.

         The Institute of Food Science & Technology (IFST) is the
    independent non-profit professional qualifying body for food
    scientist and technologists, a UK-based body with international
    interests. Its home page on the World Wide Web is at
    http://www.easynet.co.uk/ifst/

KEY DEFINITIONS

Food science --

         is a coherent and systematic body of knowledge and understanding
    of the nature and composition of food materials, and their behaviour
    under the various conditions to which they may be subject.

Food technology --

         is the application of food science to the practical treatment of
    food materials so as to convert them into food products of the kind,
    quality and stability, and so packaged and distributed, as to meet
    the needs of consumers for safe, wholesome nutritious and attractive
    foods.

                                *****

         Thus, food science integrates the application to food of several
    contributory sciences. It involves knowledge of the chemical
    composition of food materials (for all food consists entirely of
    chemical substances); their physical, biological and biochemical
    behaviour; human nutritional requirements and the nutritional factors
    in food materials; the nature and behaviour of enzymes; the
    microbiology of foods; the interaction of food components with each
    other, with atmospheric oxygen, with additives and contaminants, and
    with packaging materials; pharmacology and toxicology of food
    materials, additives and contaminants; the effects of various
    manufacturing operations, processes and storage conditions; and the
    use of statistics for designing experimental work and evaluating the
    results.

         Likewise, food technology draws on, and integrates the
    application to food of, other technologies such as those of steel,
    tinplate, glass, aluminium, plastics, engineering, instrumentation,
    electronics, agriculture and biotechnology.

FAQ GROUPINGS

         In the interests of "user-friendliness" the FAQ is written so
    that, as far as possible each answer is self-contained. This of
    necessity results in some repetition of material in the answers to
    related question For convenience, the FAQs are in four Groups as
    follows:

         GROUP 1 FOOD AND NUTRITION
         GROUP 2 FOOD SAFETY
         GROUP 3 ADDITIVES AND PACKAGING
         GROUP 4 SCIENCE AND FOOD

         The following is a summary of the questions, by the grouping
    described above. The group answers can be found under headings of the
    format: "ANSWERS TO GROUP [number] QUESTIONS - [group name]",
    excluding the quotes and square brackets, and all capital letters.
    When the answer to a question is given, the question and question
    number will be repeated in the line above it.

GROUP 1 -- FOOD AND NUTRITION
    1.What is good/bad food?
    2.What is a good diet?
    3.Do I need to worry about getting enough protein?
    4.Is sugar harmful?
    5.Isn't honey healthier than sugar?
    6.Why is sugar used in foods?
    7.Is salt harmful?
    8.Why is salt used in foods?
    9.Are fats harmful?
    10.What about different types of fat?
    11.Should we cut out all fats?
    12.What is a hydrogenated vegetable oil?
    13.What are trans fatty acids?
    14.Is margarine better for us than butter?
    15.Aren't natural foods better for us than processed foods?
    16.Why are foods processed?
    17.Is a vegetarian diet better for us?
    18.Isn't it more expensive to eat a 'prudent' diet?
    19.Do we need more vitamins and minerals?
    20.Do organic foods taste better?
    21.What foods are good for arthritis?
    22.Is ginseng/royal jelly/pollen/lecithin/kelp good for me?
    23.What are 'junk foods'?

GROUP 2 -- FOOD SAFETY
    1.What is food poisoning?
    2.Why has food poisoning increased so much?
    3.Why all the fuss about food hygiene?
    4.Aren't  we  losing  natural  immunity by producing foods with no
      pathogens present?
    5.How can food poisoning be prevented?
    6.What about irradiation of food?
    7.Isn't genetic modification a dangerous interference with nature?
    8.Doesn't  gene  transfer  from  one species to another create the
      risk of ethical problems or even cannibalism?
    9.Shouldn't  all  genetically  modified foods, or those containing
      genetically modified ingredients, be labelled as such, to warn
      consumers?
    10.With regard to BSE, is British beef safe to eat?

GROUP 3 -- ADDITIVES AND PACKAGING
    1.Why are food additives used?
    2.But aren't additives dangerous?
    3.Food colours are only cosmetic -- shouldn't they be banned?
    4.Why are foods packaged?
    5.What function does packaging perform?
    6.Do  we  really  need  the  protection  that packaging is said to
      provide?
    7.Is packaging wasteful of materials and energy?
    8.Can  packaging  and energy usage be reduced without compromising
      the protection it gives to the food?
    9.Why are there so many different types of packaging materials?
    10.Why are some packages difficult to open?
    11.What about recycling of packaging?
    12.What about returnable, refillable systems?
    13.Why does packaging contribute so much to household waste?
    14.Do packaging materials affect the food in them?

GROUP 4 -- SCIENCE AND FOOD
    1.What is food science? What is food technology?
    2.Wouldn't our food be even better without scientists and technologists
      interfering with it?
    3.Why do scientific experts often disagree?
    4.Doesn't hindsight show that the experts always "got it wrong"?

ANSWERS TO GROUP 1 QUESTIONS - FOOD AND NUTRITION ***************************

1.What is good/bad food?

         In keeping with their Code of Professional Conduct, food
    technologists in industry take great care to ensure that food
    products are safe and wholesome. But eating or drinking too much of
    any food can be bad for you -- too much water can kill you. We
    shouldn't think of good foods or bad foods, but of good or bad diets.

2.What is a good diet?

         A good diet is a balanced one; lots of different foods and not
    too much of any one food. That way you get all the nutrients that you
    need. Many countries have guidelines for healthy diets, including in
    some cases recommended daily amounts of specific nutrients. However,
    it is emphasised that these are for healthy individuals, not for
    those with disease symptoms, food allergies, or intolerances. These
    people should consult a dietitian or physician.

3.Do I need to worry about getting enough protein?

         You will automatically get enough protein to stay healthy if you
    eat a varied diet and sufficient of the wide range of foods available
    to stop you feeling hungry.

4.Is sugar harmful?

         Not in itself. However, if you eat a lot of sugar in the form of
    sweets (candy), you may not eat enough of all the other foods needed
    to provide your body with the nourishment it needs. Sugar can cause
    dental decay if you eat sweets or drink sugar-sweetened drinks
    between meals. You need to clean your teeth afterwards in the
    conventional way or by eating a piece of cheese. Otherwise the sugar
    sticks to your teeth causing plaque and decay.

5.Isn't honey healthier than sugar?

         Not really. Honey is largely a strong solution of sugars called
    fructose and glucose, which affect teeth only very slightly less than
    ordinary sugar (sucrose). There is nothing specially healthy about
    honey. The traces of micronutrients it contains are too small to make
    any significant contribution to our diet.

6.Why is sugar used in foods?

         Sugar is used in some foods to make them sweet, in others in
    small quantities to enhance the flavour but not enough to make them
    sweet. In some foods, however, sugar is an essential part of the
    structure and recipe; for example in cakes or biscuits (cookies).

7.Is salt harmful?

         Salt is essential to a healthy diet. We need about 1 g of salt a
    day. However, many of us consume about 10 g a day, ten times as much
    as we really need. A single dose of ten times that amount could be
    fatal! There is evidence that, for some people, too much salt can be
    a contributory factor to high blood pressure. Just how much is 'too
    much' varies from person to person. Prudent advice would be to reduce
    consumption to around 5 g per day.

8.Why is salt used in foods?

         There is enough salt naturally present in food to satisfy our
    daily 1 g need. However, salt is sometimes added during processing or
    cooking of food, and is also often sprinkled on a meal by consumers
    to enhance and improve the taste and flavour. Bread, tomatoes, boiled
    eggs do not taste good enough for many people unless salt is added.
    It is also used to preserve some foods. Salt curing is one of the
    earliest known forms of food preservation.

9.Are fats harmful?

         As with everything else, but more importantly with fats, too
    much is harmful. Many common diseases such as heart disease are
    linked to high consumption of fats, more especially saturated fats --
    the type mostly found in animal fat.

10.What about different types of fat?

         Fats in foods, or, more correctly, their fatty acids, are of
    three main types, saturated, monounsaturated and polyunsaturated.

         Saturated fatty acids carry a full quota of hydrogen atoms in
    their chemical structure. This is the type that increases the amount
    of cholesterol in the blood and is considered a risk factor in heart
    disease; animal fats are the main source.

         When one pair of hydrogen atoms is missing, the fatty acids are
    termed monounsaturated. They do not raise blood cholesterol and may
    even be beneficial. The main sources are olive oil and rapeseed oil
    (used in some margarines and low fat spreads).

         When more than one pair of hydrogen atoms is missing, the fatty
    acids are termed polyunsaturated. They predominate in most vegetable
    oils. Most appear to have no effect on blood cholesterol levels but
    are useful if they replace saturates in the diet. However, those
    found in fatty fish and fish oils (termed omega-3 polyunsaturated)
    are considered to help to lower cholesterol and therefore to be
    beneficial.

11.Should we cut out all fats?

         No, because some fatty acids are essential, and we need a
    certain amount of fat in the diet to be able to absorb the
    fat-soluble vitamins. Compared with an average Western diet, a
    prudent diet would contain a reduced intake of total fat, and, within
    that, a lower proportion of saturated fat and a higher proportion of
    mono- and polyunsaturated fats.

12.What is a hydrogenated vegetable oil?

         Vegetable oils, as the name implies, are liquid at room
    temperature. To make them suitable for use in margarines and
    shortenings, they are hydrogenated, i.e. treated with hydrogen, to
    solidify them. The hydrogenation process makes them more saturated.

13.What are trans fatty acids?

         Unsaturated fatty acids in foods can exist in two
    differently-shaped forms, scientifically described as the cis and
    trans forms. Some trans fatty acids are naturally found in milk and
    butter. When oils are hydrogenated, the unsaturated fatty acids
    become partially-saturated though retaining a degree of unsaturation.
    In the course of this, these still partially-unsaturated fatty acids
    have, to some extent, become converted to the trans form. While some
    research suggests that trans fatty acids may be harmful, the evidence
    is somewhat conflicting. As yet there is no official guidance on the
    subject, other than that the amount currently consumed should not be
    increased.

14.Is margarine better for us than butter?

         There is no simple answer. Butter contains more saturated fatty
    acids than margarine, but less trans fatty acids than some
    margarines.

15.Aren't natural foods better for us than processed foods?

         Nearly everything we eat comes originally from a natural source,
    but much of it is processed to preserve it so that it keeps better
    (e.g. canned, frozen or chilled foods); or to make it easier to eat
    (like wholemeal bread, a highly processed food made from wheat); or
    to make it safer (like milk that is pasteurised).

         There is no simple answer to the question. In some instances
    processed food is better for us, for example because harmful
    substances naturally present have been removed or destroyed during
    processing, or because the food has been enriched with nutrients. In
    many instances there is no difference. It could be argued that, taken
    in isolation, an apple for dessert is better for you than a chunk of
    Black Forest Gateau covered in cream; but even in the healthiest diet,
    there is room for an occasional indulgence.

16.Why are foods processed?

         To make them palatable, edible, convenient and with suitable
    keeping properties, Processing also adds variety to the diet by
    making foods from combinations of ingredients, as cooks have done
    down the ages.

17.Is a vegetarian diet better for us?

         Not necessarily. Current nutritional advice, to eat less fat,
    more fibre, more fresh fruit and vegetables and more starchy foods,
    may indeed be easier to achieve with a vegetarian diet. However,
    animal foods provide a concentrated source of protein, vitamins and
    minerals. These nutrients can be obtained from a vegetarian diet, but,
    unless it is expertly-designed, there could be difficulties with
    protein quality and with some micro-nutrients, especially with
    calcium and vitamin B2 (riboflavin) if milk products are rejected.

         [Note: Whereas vegans are very well informed about problems of
    obtaining sufficient vitamin B12 in a vegan diet, and there are
    numerous yeast-based spreads and supplements for their use, no
    warning is given anywhere in vegetarian/vegan literature about
    vitamin B2. In a typical western diet, some 40 per cent of the
    vitamin B2 intake derives from milk products. Someone switching to a
    vegan or strict vegetarian diet that excludes milk products will not
    only lose a major source of calcium, but will (in most cases,
    unknowingly) lose that 40% of vitamin B2. That is why we rectify that
    information deficiency in this FAQ, so that the deficits can be made
    up from other sources].

         There is an increase in the number of people who are vegetarian;
    either because they are concerned about animal welfare, especially of
    farm animals, and do not wish to eat meat or animal products, or
    because they believe that there are health benefits in following a
    vegetarian diet. The Vegetarian Society provides a wealth of
    vegetarian nutrition information to help ensure the nutritional
    adequacy of such diets.

18.Isn't it more expensive to eat a 'prudent' diet?

         Eating more fruit and vegetables and less fat does at first
    sight cost more, and needs more careful selection of foods. On the
    other hand, if these 'prudent diet' foods are replacing prepared
    convenience foods and fatty-sugary desserts, there may actually be a
    cost-saving.

19.Do we need more vitamins and minerals?

         A balanced and varied diet -- not too much of anything -- will
    normally supply enough from a nutrition point of view. There may be
    problems for children, adolescents, the elderly, women during
    pregnancy and lactation, and people on slimming diets. These people
    would probably benefit from a vitamin and mineral supplement. There
    is also increasing evidence that certain vitamins (i.e. vitamins C
    and E) have additional beneficial properties as antioxidants.

20.Do organic foods taste better?

         Some people who favour organic foods for other reasons claim
    that they taste better; but there is so much flavour variation among
    different varieties, different degrees of ripeness or freshness or
    length of storage of the same fruit or vegetable, that it is very
    difficult for individuals to make true comparisons.

         Generally, when attempts have been made to carry out
    scientifically-designed blind tasting tests on the same variety,
    organic versus non-organic, taste panels have been unable to detect a
    flavour difference.

21.What foods are good for arthritis?

         No individual foods will positively help disorders of this kind,
    although there is some evidence that a diet low in saturated fats and
    high in polyunsaturated fatty acids (particularly the omega-3
    polyunsaturated fatty acids) could benefit sufferers. Although there
    are various anecdotal claims about benefit from avoiding certain
    foods, there is little or no scientific evidence to support them.

22.Is ginseng/royal jelly/pollen/lecithin/kelp good for me?

         No convincing scientific evidence has so far been forthcoming to
    substantiate claims for any of these supplements.

23.What are 'junk foods'?

         This term has no specific meaning. It is an invented label which
    some people have applied to foods of which they disapprove. It has,
    for example, been applied indiscriminately to all fast food and all
    snack foods. It has also been applied to any food high in fat and/or
    sugar (and so in calories) but low in other nutrients. However, there
    is no evidence that such foodsare other than acceptable as part of a
    balanced diet.

ANSWERS TO GROUP 2 QESTIONS - FOOD SAFETY ***********************************

1.What is food poisoning?

         Food poisoning is illness caused by any harmful amount of a
    natural or contaminating substance in a food, but especially illness
    caused by some highly infective kinds of bacteria. If not prevented
    -- as it can be by care and good hygiene -- some kinds of bacteria
    can grow to large numbers in food and produce toxins (poisons) some
    of which are difficult to destroy by cooking. Other kinds can cause
    illness by growing to large numbers in the digestive system. Symptoms
    include abdominal pain, diarrhoea and vomiting, and may last from a
    few hours to a few days. In extreme cases food poisoning can prove
    fatal, especially to babies, the elderly and others with weakened
    immune systems.

2.Why has food poisoning increased so much?

         Food scientists and technologists in industry take great care to
    try to ensure that food products are safe and wholesome. It is
    probable that increased food poisoning statistics are due to a
    combination of the following factors:-

         1) increased public awareness, so that large numbers of
    previously unreported 'stomach upsets' are now increasingly reported
    as cases of food poisoning;

         2) changing lifestyles, including changed shopping habits --
    shopping less frequently in larger amounts and consequently storing
    food for longer periods;

         3) the increased marketing of chilled prepared dishes, which
    need shorter times between purchase and consumption and more
    carefully controlled low temperature domestic storage than many
    people have understood or provided;

         4) the emergence of some hitherto unknown or new strains of
    micro-organisms.

3.Why all the fuss about food hygiene?

         It is a fact of life that food is threatened by dangerous
    microbes at every stage from farm to the table. So food safety calls
    for many measures and great care at every stage or the food chain.
    Leave a single loophole anywhere, and all the other efforts may be in
    vain. So there are two overriding needs in the manufacture of safe
    and wholesome foods; the first, in every food operation, knowledge of
    what the law requires and of how to set up a sound method of handling
    and an effective quality and safety control system; and the second,
    knowledge and practice of food hygiene by everyone who handles or
    takes decisions about handling, food, whether in factories,
    distribution, retail, catering (foodservice) or in the home.

         In addition to training of adults in food businesses, therefore,
    many consumers need to learn a lot more about food hygiene, and
    tomorrow's adults now at school should be taught food hygiene so that
    it becomes second nature to them.

4.Aren't we losing natural immunity by producing foods with no pathogens
  present?

         That fear is groundless. The opposite view, that all food should
    be completely sterile, is totally unrealistic. Bacteria are around us
    all the time .There is no way that food can be made sterile, except
    by putting it in an hermetically-sealed container (e.g. a can) and
    treating it with a defined heat process to sterilise it; and even
    then, once the can is opened, the food is exposed to the atmosphere
    and contamination by airborne microorganisms. But when food is
    consumed, it is not the presence of microorganisms that is of
    concern. Danger only comes if they are allowed to multiply to large
    numbers in food or in the digestive system. This is preventable by
    taking great care and ensuring good hygiene at all stages of raw
    material handling, manufacture, distribution, retailing, catering
    (foodservice) and in the home.

5.How can food poisoning be prevented?

         There is no single answer. It needs a combination of measures
    and safeguards all the along the food chain from farm to table. See
    the answer to FAQ 3 "Why all the fuss about food hygiene?"

6.What about irradiation of food?

         Irradiation is a comparatively new method, one method among many,
    of safe food preservation. It is, however, the only method (apart
    from ultra-high pressure) of pasteurising without use of heat, and
    can therefore be valuable in a limited number of cases; for example,
    soft fruits and prawns, where quality is retained better than in heat
    pasteurisation. It is a controversial technique but, despite media
    scare stories, tests show that it is a safe and reliable process.
    Whether, and to what extent, it will be used for any particular food
    in a country will depend on governmental approval, economics and
    public acceptance

         As irradiated foods come on the market, so long as there is a
    continuing public demand for unirradiated versions they will
    obviously continue to be marketed alongside the irradiated versions.
    But where the quality and safety of the irradiated products prove
    superior, and the economics are viable, concerns will in time
    disappear. This is exactly what happened a few generations ago when
    similar concerns were expressed about permitting pasteurisation of
    milk; yet today people happily and safely drink pasteurised milk. No
    doubt the same will occur with acceptance of irradiated foods in the
    future.

7.Isn't genetic modification a dangerous interference with nature?

         Genetic modification has been used for countless years and
    applies to all the food we eat. Traditional breeding methods to
    improve animals and plants are genetic modification by slow,
    hit-and-miss means. Science now enables it to be done systematically
    and more rapidly. What is different, and could not be done by
    traditional breeding, is the purposeful copying of genes from one
    species to another.

         Professional food scientists are concerned to serve the public
    interest by furthering the application of science and technology to
    all aspects of the supply of safe, wholesome, nutritious and
    attractive food, nationally and internationally. The newer kinds of
    genetic modification can provide immense benefits in human well-being
    world-wide, especially in medicine, agriculture and food. Yes, like
    every bit of mankind's progress from being a cave-dweller, it is a
    form of interference with nature. Of course any new technology has
    potential hazards. If these frightened mankind off all new
    technologies we would still be living in the Stone Age. The answer is
    for scientific effort to be made to foresee hazards and eliminate
    them, for example, to avoid the risk of loss of genetic diversity.
    That is why, for example, the introduction of any new
    genetically-modified food is controlled in the UK in accordance with
    the stringent assessment and recommendations of the UK Advisory
    Committee on Novel Foods and Processes.

8.Doesn't  gene  transfer  from  one  species to another create the risk of
  ethical problems or even cannibalism?

         The officially appointed UK Committee on the Ethics of Genetic
    Modification and Food Use, chaired by the Rev. John Polkinghorne,
    carried out a wide public consultation and issued a report in
    September 1993 on all of the moral and ethical issues involved. This
    was accepted by the UK Government and welcomed by IFST. The Committee
    found that the concerns were misconceptions rather than of real
    substance, arising from lack of knowledge, outside the scientific
    community, of just what was involved.

         The fact is that any gene extracted from one species for copying
    into another, is not itself inserted but is copied in the laboratory
    and diluted millions of times before a single gene is transferred.
    The chance that the original gene would be found are much less than
    the chance of recovering a particular drop of water from all the
    oceans of the world. If this were widely understood fears of
    cannibalism or of contravening religious food taboos would be seen to
    be unwarranted. Unfortunately, this fact does not make good media
    copy, whereas sensational "cannibalism" scare stories do.

         The Polkinghorne Committee's conclusions were:

         a. genetic modification of food and medicines is here to stay.
    It is not something to be stopped, and it would not be ethically
    right or necessary that it should be;

         b. there is no reason for any ban on the use of copy genes of
    human origin or from animals subject to dietary restrictions, but
    scientists working in this field should be discouraged from using
    such genes where alternatives would be equally effective;

         c. products containing such copy genes should be labelled to
    enabled consumers to make informed choices;

         d. government and industry should look for ways of explaining
    genetic modification to the general public.


9.Shouldn't all genetically modified foods, or those containing
  genetically modified ingredients, be labelled as such, to warn
  consumers?

         There are two distinct kinds of genetic modification. The first
    is as old as the hills, and applies to all the food we eat.
    Traditional breeding methods of improvement are genetic modification
    by slow, hit-and-miss means. Science now enables it to be done
    systematically and more rapidly. That kind of modification
    objectively needs no special label indication -- otherwise it would
    have to be given on virtually all foods. Yet if the ready to eat
    product still contains genes incorporated by modern methods, informed
    consumer choice requires label information to that effect. In the UK
    there is a voluntary agreement by manufacturers and retailers to give
    such information, and a similar agreement is being developed across
    the whole EU. These developments have been welcomed by IFST.

         The second kind, which could not be done by traditional breeding,
    is copying genes from one species to another. If some consumers wish,
    for whatever reason, to avoid purchasing products of this second
    kind, if the copy genes remain present in the food product, that
    information should be given on the label.

         This dual approach was adopted in the recommendations of the UK
    Food Advisory Committee, accepted by the Government and welcomed by
    IFST. It is now also the basis of EU law.

10.With regard to BSE, is British beef safe to eat?

         BSE is an extremely serious disease of cattle, the eradication
    of which is of primary importance to safeguard herds, and hence
    future supply of dairy and bovine meat products for the human and pet
    food chains, together with important bovine by-products. For there to
    be any risk to humans consuming beef, two conditions would both have
    to be fulfilled: that BSE could be transmitted from cows to humans;
    and that parts of the animal capable of carrying the infective agent
    could enter the human food chain.

         As to the first, the emergence in the UK during 1994 to early
    1996 of ten anomalous cases of Creutzfeldt-Jakob Disease (CJD) of a
    previously unrecognised pattern, reviewed by the UK CJD Surveillance
    Unit (CJDSU), led the Spongiform Encephalopathy Advisory Committee
    (SEAC), in the absence of other explanation at the time, to the
    conjecture that the UK cases were "most likely" to have been caused
    by exposure to infected cattle brain or spinal cord before 1989 (at
    which time they were banned from the food chain). Since then the
    number of cases has slowly increased to over 20, and research has
    resulted in some scientific evidence consistent with transmission, at
    least to some humans.

         As to the second, while the BSE infective agent can be detected
    in the brain, spinal cord and retina of BSE-infected cows, extensive
    tests have so far failed to detect it in muscle meat or milk of
    infected cows. Measures have been taken, and strengthened, to exclude
    from the food chain certain parts of the animal (specified bovine
    materials, SBM), including all those parts shown to be capable of
    carrying the infective agent. These measures require the most
    stringent enforcement and heavy penalties for evasion. These
    safeguards do not, of course, protect against possible consequences
    of having consumed infective SBM in the past.

         Having regard to the present scientific evidence, therefore, and
    provided that the above measures are fully implemented, consumption
    of muscle meat, milk and tallow from British cows, would appear to
    involve virtually no risk of causing CJD, i.e. to be safe within the
    normal meaning of the term. SEAC has stated that, if there is any
    risk to humans, it is extremely small, and no greater for children,
    hospital patients, pregnant women or people who are
    immuno-compromised than for healthy adults.

         As regards animal health, measures have been taken, and
    strengthened, to reduce the incidence of BSE in cows and these have
    led to a dramatic reduction in new cases and are expected to lead to
    the virtual elimination of the disease.

         On the basis of present scientific knowledge, no further
    animal-related measures are needed.

    While that sums up the present state of knowledge, scientists always
    have to keep open minds. They have to act on existing knowledge while
    recognising that further research will bring new information and
    knowledge, which may in turn lead to revised conclusions.

ANSWERS TO GROUP 3 QUESTIONS - ADDITIVES AND PACKAGING **********************

1.Why are food additives used?

         Many foods depend on additives for safety, stability or
    preservation. Preservatives inhibit growth of microbes that cause
    food poisoning. Ham and bacon would be highly dangerous without the
    preservative that also gives them their characteristic colour.
    Freedom from separation, or a smooth creamy texture depends on
    emulsifiers. Without other kinds of additives many foods would look
    less pleasant, or taste less pleasant, or go off more quickly, or
    cost more.

2.But aren't additives dangerous?

         All additives in the UK and Europe are controlled by law, and
    only those are permitted that have undergone stringent tests for need
    and for safety in use, and have been been found satisfactory by
    independent committees of scientists and medical experts. A similar
    situation applies in most other countries. Some people are allergic
    to, or intolerant of, particular additives; many more are allergic to,
    or intolerant of, substances naturally present in foods, such as
    strawberries, fish, nuts, etc.

3.Food colours are only cosmetic -- shouldn't they be banned?

         Part of the enjoyment and appeal of food is its appearance,
    including its colour. Homemakers, cooks and chefs have always used
    colours in cooking to enhance appearance or to compensate for colour
    deterioration during cooking. The same applies to some manufactured
    foods. For example without colour margarines appear grey and
    unpalatable; with colour they are visually attractive and popular.
    The colours used are only those that have been tested and found
    satisfactory by the same stringent procedures as those for additives
    in general. Colour judiciously used adds to the enjoyment of food.
    Would you want to return to only black-and-white on TV or on your
    computer screen?

4.Why are foods packaged?

         Foods are packaged to protect them and keep them in good
    condition while they are delivered to stores, stacked on shelves or
    stored at home.

5.What function does packaging perform?

         The primary packaging of the food contains it; preserves it and
    protects it from contamination or damage; carries the identification
    and description of the contents; provides visible evidence as to
    whether the package has been tampered with; and reduces household
    waste by providing only the edible part of foods.

         The outer packaging (e.g. paperboard cartons) is an essential
    means of transporting to retail stores large quantities of the packs
    for stacking on shop shelves.

6.Do we really need the protection that packaging is said to provide?

         Yes. Food safety absolutely requires it. Moreover, a World
    Health Organisation study has indicated that in developed countries
    with sophisticated storage, packaging and distribution systems
    wastage of food is estimated at only 2-3%. In developing countries
    without these systems wastage is estimated at between 30% and 50%

7.Is packaging wasteful of materials and energy?

         Of course the production of anything, including packaging
    materials, uses raw materials and energy. However, both packaging
    material manufacturers and food manufacturers operate in an intensely
    competitive environment, causing continual search for ways to
    minimise packaging costs without compromising the protection or
    presentation of the product.

         Packaging also reduces the amount of material entering the waste
    stream. Most packaged fresh and processed foods have had the
    non-edible material (e.g. husks, peels, vegetable tops, bones of
    animal or fish, etc) removed during preparation. As a result, those
    materials are used for animal feed or other purposes instead of going
    into domestic waste. Likewise, energy is saved by not having to
    transport that inedible material through the distribution and retail
    chain to the consumer.

8.Can  packaging  and  energy  usage  be  reduced  without compromising the
  protection it gives to the food?

         Here are four examples

         In 1970, the weight of a metal can for baked beans was 68.9 g.
    In 1990 the same size can weighed 56.6 g.

         In 1950, a glass milk bottle weighed 397 g. In 1990, the same
    size bottle weighed 245g.

         In 1983 a 1.5 litre PET plastic soft drinks bottle weighed 66 g.
    In 1990, the weight has been reduced to 42 g.

         In 1950 a tinplate beer can weighed 91 g. In 1990 an aluminium
    beer can weighed only 17 g, and was fully recoverable for recycling.

9.Why are there so many different types of packaging materials?

         Most food products can be packed in a variety of alternative
    ways. Manufacturers choose the most appropriate type of packaging for
    a product, depending on the nature and requirements of the product,
    the degree and nature of protection needed, the method of
    distribution, the shelf-life and the environmental impact.

10.Why are some packages difficult to open?

         the design of a package is inevitably a compromise between, on
    the one hand, the essential protection of the contents, in some cases
    requiring extra robustness or an airtight seal, and on the other hand,
    easy and convenient use, including ease of opening. A really
    well-designed pack is one that strikes an effective balance between
    these two requirements. While there are some packs that are more
    difficult to open than others, when an occasional pack is encountered
    that is virtually impossible to open, it is usually the result of a
    temporary maladjustment of a packaging machine (for example, forming
    much too tight threading of a metal cap on a bottle) rather than a
    design fault. Manufacturers are increasingly having their attention
    drawn to the special 'openability' problems encountered by customers
    with physical disabilities, and efforts to improve matters in this
    direction will benefit all users

11.What about recycling of packaging?

         The '3 R's' of current environmental packaging law and practice
    are Reduce, Re-use and Re-cycle. These are the main ways of
    minimising municipal waste disposal. As far as re-cycling of food
    packaging is concerned is concerned, the major materials have to be
    considered and dealt with separately.

         Glass, tinplate and aluminium, when recovered by re-cycling, can
    give similar performance to that provided by the virgin materials.
    Re-cycling all three reduces overall energy usage (particularly with
    aluminium). Re-cycling schemes are now in operation for the recovery
    of both tinplate and aluminium containers. Glass containers (eg. milk
    bottles) if sound can be returned and re-used; but broken glass
    ('cullet') is returned to the glassworks for re-cycling. Paper and
    paperboard can be recovered and re-cycled for newsprint, tissues, and
    some grades of paperboard.

         Various plastic materials present a variety of recovery and
    re-cycling problems. About half of all consumer goods are packaged in
    plastic of one kind or another, yet, because of the lightweight
    character of plastic packaging, it represents only 15% by weight. Its
    light weight is of course economical of materials and energy for
    transport of goods packed in plastic. Most individual plastic
    packages (without counting the weight of contents) weigh less than 10
    g, and some of these are contaminated with food residues such as
    yogurt, fats, cream and similar products. The light weight makes it
    more difficult to collect and transport for re-cycling. Lightweight
    films, bags, pouches, etc made of plastics or plastics/paper
    laminates are probably better incinerated to recover energy.

12.What about returnable, refillable systems?

         There are several requirements for a re-fillable system to work.
    Consumers must be made aware of which containers are returnable; the
    operation is local, centred around each filling plant with a radius
    of about 50-80 kilometers; the transport system for delivery and
    returns is preferably controlled by the filling plant; the cost of
    returning the empty container and of washing and handling it, must
    not exceed the cost of a single-trip container; the containers must
    be suitable for return by the consumer via conveniently sited bottle
    banks.

13.Why does packaging contribute so much to household waste?

         It is only when the package is emptied and needs to be disposed
    of that we notice it. People are seldom aware of the role of the
    packaging in protecting the product in distribution and until it is
    opened for use.

         A UK Royal Commission on Environmental Pollution found that
    total packaging (not just food packaging) contributes 1% of the total
    of all solid wastes. Total household waste contributes only 4% of all
    solid wastes.

         A study of waste by the US Chamber of Commerce indicated that
    the relationship between food waste and packaging waste was clear; as
    packaging use (and subsequent disposal as waste) increases, food
    wastage decreases.

14.Do packaging materials affect the food in them?

         The packaging material has both to preserve the food and to
    protect it from deterioration, outside contamination or damage during
    distribution and storage; and the packaging material in direct
    contact with a food must not itself harm, or be harmed by, the food.
    The packaging material for a particular food must therefore be
    carefully selected with these considerations in mind. Most countries
    have developed strict controls, based on extensive testing, for the
    use of "food contact" materials; and these help to ensure that a
    correct choice is made.


ANSWERS TO GROUP 4 QUESTIONS - SCIENCE AND FOOD *****************************

1.What is food science? What is food technology?

         *Note. The answers given are the same as the KEY DEFINITIONS
    given at the beginning of this section, but are repeated here for
    convenience

    Food science --

         is a coherent and systematic body of knowledge and understanding
    of the nature and composition of food materials, and their behaviour
    under the various conditions to which they may be subject.

    Food technology --

         is the application of food science to the practical treatment of
    food materials so as to convert them into food products of the kind,
    quality and stability, and so packaged and distributed, as to meet
    the needs of consumers for safe, wholesome nutritious and attractive
    foods.

         Thus, food science integrates the application to food of several
    contributory sciences. It involves knowledge of the chemical
    composition of food materials (for all food consists entirely of
    chemical substances); their physical, biological and biochemical
    behaviour; human nutritional requirements and the nutritional factors
    in food materials; the nature and behaviour of enzymes; the
    microbiology of foods; the interaction of food components with each
    other, with atmospheric oxygen, with additives and contaminants, and
    with packaging materials; pharmacology and toxicology of food
    materials, additives and contaminants; the effects of various
    manufacturing operations, processes and storage conditions; and the
    use of statistics for designing experimental work and evaluating the
    results.

         Likewise, food technology draws on, and integrates the
    application to food of, other technologies such as those of steel,
    tinplate, glass, aluminium, plastics, engineering, instrumentation,
    electronics, agriculture and biotechnology.

2.Wouldn't  our  food  be  even better without scientists and technologists
  interfering with it?

         No. It is the scientists and technologists, working in
    universities and research establishments, in industry, as consultants
    to industry, and in enforcement and government agencies, who extend
    the frontiers of knowledge about the properties and behaviour of food;
    apply increasing knowledge to the development of the present (and
    future) wide variety of safe and attractive foods; design and operate
    quality assurance systems to ensure that quality and safety are
    maintained during the manufacture, distribution and retailing of
    foods; operate surveillance systems to ensure that legal, quality and
    safety requirements are being met.

3.Why do scientific experts often disagree?

         Personal opinions vary in every walk of life, but scientists
    disagree far less than the media suggest. However, at the 'cutting
    edge' of scientific research, there can be genuine disagreements on
    the validity or interpretation of available information and on how
    new research findings may affect previous interpretations. Scientists
    are accustomed to debating these matters, and it is in the course of
    thrashing out these differences and highlighting gaps of knowledge
    where further research is needed, that scientific knowledge advances.
    It requires objective judgement, without, on the one hand, undue
    zealotry or, on the other hand, defence at all costs of entrenched
    positions of past orthodoxy.

4.Doesn't hindsight show that the experts always "got it wrong"?

         No. Hindsight shows that the experts nearly always "got it
    right". It's simply that we only notice the rare instances where they
    did get it wrong. And in those instances, we have to ask why.
    Sometimes the scientists were in fact right, but human error occurred
    in applying that knowledge. Sometimes it was that the knowledge
    available at that time was insufficient. Scientists are not
    magicians. Twenty years ago they knew only a fraction of what we know
    now; which in turn is only a small fraction of what we will know in a
    few years time. Research brings new knowledge all the time and at an
    accelerating rate.

         However, our profession is the repository of existing knowledge
    in the field of food science and technology, and includes the
    researchers expanding the boundaries of that knowledge and the
    experts applying it for a safe, wholesome, nutritious and attractive
    food supply for the public benefit.

********************** END OF FAQ *****************************************
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Paul King                                      Oakville, ON
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