Archive-Name: sci/food-science-faq/part3
See reader questions & answers on this topic! - Help others by sharing your knowledge Posting-Frequency: biweekly Last-modified: 2006/06/12 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.What are low-density lipoproteins? 15.Is margarine better for us than butter? 16.Aren't natural foods better for us than processed foods? 17.Why are foods processed? 18.Is a vegetarian diet better for us? 19.Isn't it more expensive to eat a 'prudent' diet? 20.Do we need more vitamins and minerals? 21.Do organic foods taste better? 22.What foods are good for arthritis? 23.Is ginseng/royal jelly/pollen/lecithin/kelp good for me? 24.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. Research has now been convincing enough to cause the United States Department of Agriculture (USDA) to issue a warning regarding trans fats. According to the USDA website, trans fats tend to raise the level of low-density lipoproteins (LDLs) in the blood when taken in combination with saturated fats and dietary cholesterol. The USDA recommends cutting back on saturated fats, cholesterol, and trans fats to reduce the risk of heart disease. 14.What are low-density liproproteins? All lipoproteins are produced entirely inside the body as a result of digestion, so attention will be given to aspects of lipoproteins having to do with our diet. Fats are packaged in the intestine inside of cell membrane material called chylomicrons. These consist of triglycerides and cholesterol packed inside a wrapper of phospholipid and protein. These chylomicrons travel to parts of the body so that the fat inside them can be deposited to other cells. What is left is sent to the liver for recycling. In the liver, the triglycerides are used to make many different molecules, including cholesterol, which can be produced from excess faty acids. Phospholipids, triglycerides, and cholesterol are sent out of the liver in the form of "very low-density lipoproteins", or VLDL. This gives the cells of the body a second chance at absorbing fats, plus whatever other compounds the cells need. Triglycerides get absorbed faster than cholesterol, and as a result get denser, and are called LDLs, or "Low-density lipoproteins". LDLs are almost 50% cholesterol, making them a prime cause of atherosclerosis (hardening of the arteries) if in excess in the blood. Since cholesterol can be produced by any fatty acid, "cutting back on cholesterol" means by extension, cutting back on ALL dietary fat. Ironically, dietary cholesterol is less harmful, since cholesterol must be broken down before it is absorbed into the intestinal wall. On the other hand, if the food contains a lot cholesterol, it will generally contain other fats as well, usually in even greater amounts. Foods high in cholesterol are generally from animal sources, and therefore are usually high in other fats. Reducing risk of heart ailments means reducing the prescence of LDLs in the blood. This may be done in several ways, involving dieting, excercise, or preferably both. 15.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. 16.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. 17.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. 18.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. 19.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. 20.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. 21.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. 22.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. 23.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. 24.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 **************************************** . ********************** END OF FAQ ***************************************** 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 ***************************************** User Contributions: |
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