ugg kensington 39 A review of the benefits of processed foods
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1. Introduction and definitions
We all process foods everyday when preparing a meal for ourselves or our family and virtually all foods undergo some form of processing before they are ready to eat. Some foods are even dangerous if eaten without proper processing. The most basic definition of food processing is „a variety of operations by which raw foodstuffs are made suitable for consumption, cooking, or storage“. Food processing includes any action that changes or converts raw plant or animal materials into safe, edible and more enjoyable, palatable foodstuffs. In large scale food manufacture, processing involves applying scientific and technological principles to preserve foods by slowing down or stopping the natural processes of decay. It also allows changes to the eating quality of foods to be made in a predictable and controlled way. Food processing also uses the creative potential of the processor to change basic raw materials into a range of tasty attractive foods that provide interesting variety in the diets of consumers. Without food processing it would not be possible to sustain the needs of modern urban populations, and the choice of foods would be limited by seasonality.
The term ‚processed foods‘ is used by many with certain disdain, suggesting that processed foods are in some way inferior to their non processed counterparts. However, it is important to remember that food processing has been used for centuries in order to preserve foods, or simply to make foods edible. In fact, processing spans the whole food chain from harvesting on the farm to different forms of culinary preparation in the home, and it greatly facilitates provision of safe food to populations around the globe.
Food processing can lead to improvements in, or damage to, the nutritional value of foods, sometimes both at the same time, and it can help to preserve nutrients that would otherwise be lost during storage. For instance, shock freezing of vegetables shortly after harvesting slows the loss of sensitive nutrients. boiling) renders them edible by destroying or inactivating specific anti nutritional factors they contain. The process of boiling vegetables does lead to losses of vitamin C but it can also release certain beneficial bioactive compounds such as beta carotene in carrots, which would otherwise be less available during digestion because the heating breaks down the plant cell walls.
For centuries, ingredients have served useful functions in a variety of foods. Our ancestors used salt to preserve meats and fish, added herbs and spices to improve the flavour of foods, preserved fruit with sugar, and pickled vegetables in a vinegar solution. Today, consumers demand and enjoy a food supply that is nutritious, safe, convenient and varied. food additives and advances in technology) help to make this possible. Food additives are added for a particular purpose whether it is to ensure food safety, to add nutritional value or to improve food quality. They play an important role in preserving the freshness, safety, taste, appearance and texture of foods. For example, antioxidants prevent fats and oils from becoming rancid whereas emulsifiers stop peanut butter from separating into solid and liquid fractions. Food additives keep bread free of mould for longer and allow fruit jams to „gel“ so they can be spread onto bread.
Humans have been processing foods for centuries (see table 1). The oldest traditional techniques included sun drying, the preservation of meat and fish with salt, or fruit with sugar (what we now call jamming). These all work on the premise that reduction of water availability in the product increases shelf life. More recently, technological innovations in processing have transformed our food supply into the rich variety that is available in supermarkets today. In addition, food processing enables manufacturers to make nutritionally enhanced products (‚functional foods‘) with added ingredients that provide specific health benefits beyond basic nutrition.
Canning originated in the early 19th century as Napoleon’s troops faced a serious food shortage. In 1800, Napoleon Bonaparte offered an award of 12,000 francs to anyone who could devise a practical method for food preservation for armies on the march; he is widely reported as saying „An army marches on its stomach“. After years of experiment, Nicolas Appert submitted his invention of sealing foods in glass jars and cooking them, and won the prize in 1810. The following year, Appert published L’Art de conserver les substances animales et vgtales (or The Art of Preserving Animal and Vegetable Substances), which was the first cookbook of its kind on modern food preservation methods. Also in 1810, the Englishman Peter Durand applied the Appert process using various vessels made of glass, pottery, tin or other metals and obtained the first canning patent from King George III. This can be considered the origin of the modern can.
The modern frozen food industry was started by Clarence Birdseye in America in 1925. He was a fur trader in Labrador, and noticed that fillets of fish left by the natives to freeze rapidly in arctic winters retained the taste and texture of fresh fish better than fish frozen in milder temperatures at other times of the year. The key to Birdseye’s discovery was the importance of the speed of freezing, and he pioneered industrial equipment to freeze foods rapidly. We know today that, coupled with appropriate treatment prior to freezing, this rapid freezing has the potential to ensure excellent preservation of nutritional value for a wide range of foods.
Table 1. Chronological development of food processing techniques
3.1 Palatability and sensory improvements
Virtually all foods undergo some form of processing before they are ready to eat. At its most simple, this could be peeling a banana or boiling a potato. However, with some products such as wheat, it requires quite elaborate processing before it becomes palatable. First there is grain harvesting, then removal of the husk, stalk, dirt and debris. The cleaned up grain is usually cooked or milled into flour and then it is often made into another product such as bread or pasta.
The organoleptic (sensory) quality of some foodstuffs benefits directly from processing techniques. For example, baked beans derive their creamy texture from the heat treatment during canning. Extruded and puffed products like breakfast cereals or crisps would be almost impossible to make without large scale modern food processing equipment.
3.2 Preserved and improved nutritional quality
Processing such as freezing preserves the nutrients that are naturally present in foods. Other processes, like cooking, can sometimes improve the nutritional value by making nutrients more available. For example, cooking and canning tomatoes to make tomato paste or sauce renders the bioactive compound lycopene more available to the body. When processed carefully, cocoa and chocolate processing preserves the levels of flavonoids like epicatechin and catechins, but their contents can be reduced with poor processing conditions. Lycopene and flavonoids have antioxidant properties which, according to some research, contribute to maintenance of heart health and may reduce the risk of certain cancers.
Researchers are currently investigating the manipulation of nutrient digestibility through food processing to create foods that have enhanced nutrient availability. For example, it appears that homogenisation of milk can reduce droplet size of fat, caseins and some whey proteins. This seems to result in a better digestibility than untreated milk. Early research suggests that manipulation of triacyglycerol (fork like basic skeleton of fats) structures may also affect the digestibility of fats, thus altering their impact on cardiovascular disease risk post ingestion. pasteurisation of milk). water available for bacterial growth) and alter the pH of foods and thereby restrict the growth of pathogenic and spoilage micro organisms and retard enzyme reactions. Other techniques such as canning, pasteurisation and Ultra High Temperature (UHT) destroy bacteria through heat treatment.
Another benefit of processing is destruction of anti nutritional factors. For example, cooking destroys protease inhibitors such as trypsin inhibitors found in peas, beans or potatoes. Trypsin inhibitors are small globular proteins which inhibit the action of the human digestive enzymes trypsin and chymotrypsin required to break down dietary proteins. If present in foods, they can reduce the nutritional value of the food and in high doses they have been shown to be toxic in animal studies, with some human evidence showing similar results. Prolonged boiling also destroys the harmful lectins present in legumes such as red kidney beans. Lectins make red blood cells clump together and if not degraded prior to consumption cause severe gastro enteritis, nausea and vomiting.
3.4 Preservation, convenience and choice
Food processing enables us to enjoy a varied diet that fits with the fast pace and pressures of our modern day society. People are increasingly travelling abroad for their holidays, thus they are exposed to a wider selection of flavours and styles of foods. Individuals are also changing the way they spend their time, and many choose not to cook foods from scratch. To meet consumer expectations, manufacturers are therefore producing sophisticated foods of restaurant quality, or from far away countries to cook and enjoy in our own homes.
In the Western world, our foods are predominantly based on five staple crops rice, wheat, maize, oats and potatoes. The array of characteristics we are used to in our foods are derived from these five simple staples combined with modern food processing techniques. Therefore, it can be said that today we have become accustomed to a diversity of foods, made from a narrow range of plant species, to provide our nutrition. This transformation of staple foods into processed foods would not be possible without modern food technology.