Pears preserving

Fruits are seasonal in temperate climates, and a good harvest may be followed by a shortage if there is no method of preservation. The hard fruits, apples and pears, have traditionally been stored in cool places and may then last for several months, depending on the variety Refrigeration has extended the storage life, and made this more reliable. 

Bacteria not only attack teeth but can also make people extremely sick. Therefore, canned food must be specially prepared to prevent the growth of bacteria. This is usually done by boiling or steaming. People who can their own food at home, however, do not have the sophisticated machines that food-canning manufacturers have. Even so, there are other methods that home canners can use to preserve their own food and keep their families safe. For example, high heat can be used to kill the bacteria Clostridium botulinum, which causes one deadly form of food poisoning called botulism. Acidic conditions will also kill C. botulinum. Because the bacteria cannot survive at a pH below 4.5, very acidic foods such as tomatoes, pears, and peaches are safe for home canning. 

Gorny J, Hess-Pierce B, Cifuentes R and Kader A. 2002. Quality changes in fresh-cut pear slices as affected by controlled atmospheres and chemical preservatives. Postharvest Biol Technol 24 271-278. 

Olivas GI, Rodriguez JJ and Barbosa-Canovas GV. 2003. Edible coatings composed of methylcellulose, stearic acid, and additives to preserve quality of pear wedges. J Food Proc Preserv 27(4) 299—320. 

Preservatives. Sulfur compounds, such as sulfur dioxide and sodium bisulfite, are used commercially to preserve the color of various food products, such as orange juice, dehydiated fruits and vegetables, such as apricots, carrots, peaches, pears, potatoes, and many odiers. Concentrated sulfur dioxide is used in wine-making to destroy certain bacteria. The color preservation of canned green beans and peas is enhanced by dipping the produce in a sulfite solution prior to canning. In 1986, some of these compounds and uses were put under closer regulation in the United States. 

All varieties of pears, even storage varieties, can only be kept for a few weeks without cold storage. They become mealy or their flesh turns brown after a short period of optimum ripeness. This period is particularly short in summer and autumn cultivars. This is why pears are often preserved as tinned fruit, in addition to being eaten as fresh fruit. A few special varieties are used for juice production and for manufacture of fruit brandies. Although they have a lower vitamin content than apples, fully mature, well developed pears are delicious. 

The triorganotin species have been used as industrial biocides for over 30 years [117, 118]. Examples are triphenyltin hydroxide (structure 5) for fungal diseases on celery, rice, sugar beets, and coffee tricyclohexylstannyl-1,2,4-triazole (structure 6) as an acaricide for apple, pear, and citrus fruit trees bistributyltin oxide (structure 7) as a wood preservative and tributyltin-methylacrylate monomers (structure 8) polymerized with other acrylates to yield a marine antifoulant polymer that prevents the build of up barnacles, algae, and other marine animals on ships. 

Fruits can also be preserved in alcohol—cherries in brandy are particularly good. Simply fill ajar with washed, stoned cherries (use an olive stoner), add a little sugar and cover with brandy. Shake the jar about once a week. The cherries are ready to eat after three months, and make a lovely end to a celebration meal. Pears are also a good choice of fruit to preserve (see right). 

Cactus pear extracts Liposomes Maltodextrins and inulin Spray drying Preservation at high temperature [161]... 

Solanum muricatum (family Solanaceae) This is commonly known as melon pear and originated in Peru and has been introduced to the Mediterranian countries. New Zealand, Eastern Europe and Ethiopia. The fruits are eaten raw or used for preserves. 

Since the middle of the 19 century, heat sterilization in cans and glass jars has been the most important process for fruit preservation. Undamaged, aroma-rich and not overripe fruits are suitable for heat sterilization. Aseptic canning is applicable only for fruit purees. Canned fruits used are primarily stone fruits, pears, pineapples and apples (usually apple puree). Strawberries and gooseberries are canned to a lesser extent. Canned fruits are produced in a large volume by the food industry and also in individual households. Cherries are freed from stone seeds and stems, plums/prunes, apricots and peaches are halved and the stone seeds are removed, strawberry calix is removed, gooseberry and red currant steins are removed, apples and pears are peeled and sliced. Specialized equipment has been developed for these procedures. 

Rum fruits are produced by steeping the fruit in dilute spirits in the presence of sufficient sugar. Fruits preserved in vinegar, mostly pears and plums, are prepared by poaching in wine vinegar sweetened with sugar and spiced with cinnamon and cloves. 

Preservation of pears by canning includes pears canned in water pack, juice pack, light syrup, heavy syrup or extra heavy syrup. 

A preserve made with either pears or grapes plus quinces, and cooked slowly in sweet wine or cider. 

P03Ch. The gentlest boil. Use this technique for foods that can fell apart, dry out, or overcook easily. Poaching preserves the flavor of delicate foods. Think fish, s (out of the shell), pears, and chicken breasts. 

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