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About The Omaha morning bee. (Omaha [Neb.]) 1922-1927 | View Entire Issue (April 13, 1924)
Care of Food in the Home Thu Article Will Appear in Four Inatallmeat*, a* Follow*! "Cauaet of Spoilage," "Storage," “Care of Different Kindt of Food*," "General Rule*" CAUSES OF SPOILAGE INSTALLMENT NO. I nOOD generally shows when it is spoiled by an unpleasant look, taste or smell. It may, however, be contaminated with organisms that make it unsafe for use, even though it still appears good. The causes of spoil-* age are many and varied and foods differ greatly in the kind of care needed. Foods may be spoiled by bacteria, yeasts, molds; by changes produced by heat or cold, light and loss or absorption of moisture; by insects and other house hold pests; and by parasites of food ani mals. Dirt and careless handling increase the chances of spoilage at every stage from the time food is produced until fi nally used. Right methods of care in the home can prevent or at least check much waste from these causes. 1 he waste of food through poor choice, preparation and serv ing is due to very different reasons and is not discussed here. Bacteria, Yeasts and Molds Bacteria, yeasts and molds —three types of micro-organ isms—are the most important and insidious of all causes of food spoilage. They are al most everywhere, yet their presence is often unsuspected until tney have caused food to change color, ferment or decay. Micro-organisms are distributed in all sorts of ways. Some spread them selves by rapid growth; others are carried by air, by water, by insects and animals, and on the hands and clothing of people. The growth of bacteria, yeasts and molds, like that of any other plants, is in fluenced by temperature, moisture and light. One of the chief problems in the care of food is to make these conditions so unfavorable that micro-organisms can not live or at least are unable to develop without at the same time making undesir able changes in the food itself. Pasteuri zation of milk does this by raising the temperature for a certain time to a point that destroys undesirable bacteria, but does not cook the milk. Most micro-organ isms are sensitive to cold also, at least to the extent that growth is more or less checked -by a temperature of 40° to 50° F. Drying is another way to prevent the growths of micro-organisms in foods. Dried fruits and vegetables, for instance, may keep for months in a cool, dry place, but as soon as water is added to them they will spoil as quickly as fresh kinds. Direct sunlight destroys many micro-or ganisms, but the dim light of the cellar is just right for some molds. Racteria of various sorts must be dealt with in the care of food. Lactic-acid bac teria, for example, cause milk to sour, but k do not necessarily make it unwholesome and are an aid in making butter and cheese. Other kinds, however, make foods putrefy and decay, and still others develop dangerous poisons. In addition, foods are io^ tirvp cyptai^inat**! it,.varipU9 #r*y»* with the bacteria of such diseases as ty phoid fever and paratyphoid, tubercu losis, diphtheria and dysentery. For in stance, the bacteria of typhoid and para typhoid are transmitted to food as it is handled by persons who carry these or ganisms in their bodies, though they are apparently healthy. Two varieties of the poison-producing bacteria require special mention. Bacillus enteritidis is responsible for many of the cases of so-called meat poi soning and is particularly dangerous be cause it does not give the food a spoiled taste or smell. It occurs in domestic ani mals, hence the need for great cleanliness in slaughter houses and in markets. Even home-dressed chickens may become in fected tnrougn carelessness in drawing or by flies conveying the infection! Since it is be lieved that the poison devel oped by this bacillus is not af fected to any extent by heat, cooking infected meat does not render it safe. Bacillus botulinus develops a powerful poison in the food that it infects, but this poison is destroyed by thorough boil ing. The organism does not grow well at temperatures oeiow ou r ; therefore proper refrigeration protects food from it. It has been found in sau sage, preserved meat and canned goods. Usually, but not always, the contaminated food shows plain signs of spoilage. Sus pected food should never be even tasted until after it has been heated to boiling, and some authorities advise that the boil ing be continued from 30 to 45 minutgs. Fortunately, cases of poisoning due to botulinus are rare, considering the great quantity of canned foods used. A Yeasts generally show their presence in foods containing sugar by fermenting them, as often happens in stewed or canned fruits or fruit juices. Some of these wild yeasts have been domesticated, as it were, and put to work in leav ening bread and making kefir, kumiss and other fermented milk beverages. Bacteria sometimes interfere with the action of yeast in bread making and develop sour or other bad flavors or make the bread slimy or unnatural in color. Molds spread through food as delicate velvety or powdery' growths of various colors, feeding on some of the substances and causing changes in texture and flavor. As in the case of bacteria and yeasts, some molds are cultivated and introduced into food to produce special effects. The flavor of Roquefort and Camembert cheese, for example, is due to the development of cer tain molds Since the spores of molds are easily blown about in the air and are c afeo fairlv resistant to heat, the house-’* • *• 1 ... keeper has to be constantly on the watch, especially in damp, warm weather, against molds on or even near foods. Changes Produced By Heal, Cold, Lifhl and Lon or Absorption of Moisture Heat and cold, light and loss or absorp tion of moisture have other effects on food spoilage besides those connected with growth of bacteria, yeasts and molds. Manv fresh fruits ripen so rapidly, even at ordinary room temperature, that they soon pass their prime, as everybody knows from the mealy apples often found in the dish on the sideboard. Nuts and other fat foods become rancid more quickly if stored in a warm rather than a cool place. On the other hand, temperature as low as freezing ruins both texture and flavor of some foods. Frozen potatoes, for ex ample. are watery and have an unpleasant sweetish flavor. Light also hastens the ripening of fresh fruits and vegetables. Various canned and dried products seem to keep their attrac tive color longer in light-proof containers, and the quality of table oils and fats is af fected by light as well as heat Too great circulation of air over foods may injure them. For instance, lettuce and other succulent vegetables become wilted by evaporation, while crackers and cookies lose their crispness by absorbing moisture from the air. In other words, moist foods often need to be protected from drying out and dry foods from be coming moist The wrappers and contain ers in which many commercial food prod ucts are marketed prevent such changes very effectively, and suggest good prac tices to the housekeeper. Insects and Other Household Peats Insects, rats and mice, and other house hold nests not only destroy and pollute foods in obvious ways, out they may also infect them with micro-organisms dangerous to health. The rat has been called the most destructive animal in the world, partly because it spreads bubonic plague, and the common housefly fully deserves the epithet “typhoid fever" fly. and is also a known carrier of the bacteria of cholera, dysentery and tuber culosis. Even the so-called fly specks often deposited on food and dishes may be infected with disease germs and the eggs of dangerous parasites. Food, more than anything else, draws these pests to a house, and their visits are at least discouraged by keeping supplies covered or in closed containers and by disposing of garbage promptly. Sometimes, in spite of all the house keeper’s precautions, weevils or worms develop quickly in apparently sound ce real products, dried vegetables and fruits, or nuts. In reality, these pests come from minute eggs deposited by insects in or up on grains or other seeds, or in the flavor , (Continued on Pajr»* 11)