Biotechnology is the use of microorganisms to produce something useful. It now appears possible that microorganisms could be used to solve food shortages worldwide, but how viable will this ever be?
Microorganisms are already widely used in the production of many different foods. Yeast is used in the making of wine and beer, fermenting sugars into alcohol. Yeast is also used in bread-making, the carbon dioxide produced during fermentation allows bread to rise and become fluffy and airy. Fermentation with yeast also gives a sour flavour to sourdough bread and traditional-style baguettes. Lactobacillus bacteria can be added to milk to make yoghurt. The lactobacillus ferment lactose (the sugar in milk) into lactic acid, making the milk acidic, causing the milk proteins to coagulate. This gives yoghurt its semi-solid form. Microorganisms are also used to produce soy sauce, an important flavouring used in oriental cooking, able to provide protein and flavour in a vegetarian diet. The production of soy sauce is more complicated; Aspergillus mould is added to a mixture of ground roasted wheat and soy beans which have been cooked to kill any bacteria on their surface. The Aspergillus produces enzymes which catalyse the breakdown of carbohydrates and proteins in the mixture into sugars and amino acids. Brine, otherwise known as Sodium Chloride Solution (basically salty water) is then added. This gives the soy sauce its salty flavour and helps preserve it. A yeast and lactobacillus bacteria are then added. These can both survive in conditions where there are very low oxygen levels and very high salt levels. They both ferment the sugars in the mixture. The conditions cause the Aspergillus mould to become inactive. The soy sauce is then filtered and pasteurized at 72 degrees Celsius. It is left to mature for a considerable length of time, allowing the flavours to develop. Microorganisms are also added to probiotic foods. These contain healthy bacteria which are able to live in the gut, reducing the number of harmful bacteria.
Recently, many have suggested that using microorganisms for food production may be one way to overcome world food shortages. Microorganisms can be cultivated in a fermenter to produce foods like single-cell protein (SCP) or citric acid, which is used to enhance flavour in fizzy drinks, sweets, jams and jellies. Microorganisms grown in a fermenter require nutrients and suitable temperature and pH. There are many apparent advantages to using microorganisms for food production; firstly, they grow much more rapidly than most plants and animals. Some microorganisms can double their mass within hours, meaning they can be used to produce huge amounts of food very quickly, which would be ideal in places where there are severe food shortages. The microorganisms are fairly easy to handle and manipulate, meaning producing food with them is often easier than growing crops or rearing animals. Fermenters are sheltered, so food production using microorganisms is independent of climate. This means food can be produced all year round and all over the world, without interference. In addition, pests, weeds and predators, which disrupt food production using plants and animals, are not a great concern when using microorganisms for food production. Microorganisms can also be fed on waste products from other industrial processes, meaning using microorganisms for food production is a form of recycling. This biotechnology could be used to produce large amounts of high-protein food very quickly, and could be the key to solving food shortages in developing countries. Despite this, there are drawbacks to using such methods. Cultivating microorganisms in a fermenter can be difficult, as they require specific conditions. The fermenter must be completely aseptic, meaning it must be sterilised with hot steam. The air entering the fermenter must be filtered to remove any unwanted microorganisms. If the aseptic precautions are not taken, other microorganisms may contaminate the product and reduce yield. Specific culture mediums are also required. The microorganisms may require sugars like sucrose or glucose, amino acids and a wide variety of different vitamins and minerals. These may be expensive or difficult to acquire. For maximum yield to be produced; temperature, pH, concentration of different nutrients and oxygen and carbon dioxide levels must be carefully controlled. This requires expensive sensors, air intakes and water cooling systems, which may mean that fermenters are difficult to set up in developing countries. In addition, many people disagree with using biotechnology for food production for various reasons. Some do not trust the food or believe it is unnatural. Some simply despise the bland taste and sickening texture of foods like Mycoprotien and SCP.
Biotechnology can be used in other ways to produce food. Genetic modification of crops can produce far higher yields of crops which contain higher levels of many important nutrients. This is much quicker than using artificial selection and hybridisation to produce higher-quality crops, but again, many people have health and ethical concerns over the use of genetic modification in the production of their food. Once again, many believe that organic food is better tasting than food produced using biotechnology. It should not be forgotten that there are other ways to solve food shortages. Vegetarianism means that less energy is lost in food production because the food goes through fewer trophic levels. Plant breeding programs, fertilizers, intensive farming techniques, greenhouses and hybridization can all also be used to produce higher yields from crops. Fish farming can produce large quantities of food as well.
Biotechnology has been used to make cheese, yoghurt, beer, wine and bread for thousands of years. In the future, biotechnology is sure to offer many more interesting ways to produce food. I believe that biotechnology, particularly the use of fermenters to produce SCP, can be used to feed those who are starving in the developing world. Growing SCP in fermenters is possibly the easiest and quickest way to produce large volumes of high protein food. It is scientifically possible to use biotechnology in this way to solve food shortages, but whether or not this will ever work in practice remains to be seen. I do not believe genetic modification of crops is such a good idea, as the drawbacks: worse-tasting produce and widespread ethical objection, do not seem to outweigh the advantages. In addition, I do not believe that biotechnology will ever replace conventional food production techniques completely, as I do not believe that biotechnology will ever be able to offer higher quality food than traditional farming and agriculture. While biotechnology may be the key to providing food in the third world, where there are fewer alternatives, it will not become the primary means of food production in developed countries, where organic plant and animal products are plentiful.
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