Text A. Methods of fruit and vegetables preservation

Drying, salting, cold storage, freezing, bottling and canning are methods used to preserve vegetables and fruit. If foods are kept for a few days in the air, they spoil because of the action of yeasts, bacteria and other types of microorganisms. Food preserving methods destroy these organisms or prevent their re-entry or slow down their growth.

As bacteria need moisture for their development, they cannot grow if foods are dried. Salting, like drying, reduces the moisture content of food, and, in addition, salt destroys certain organisms. Drying and salting have been practised for many centuries. Drying is still used commercially for preserving various fruit, such as grapes, apples, apricots, and vegetables, such as potatoes, onions, peppers and carrots. In some countries fruit, herbs and mushrooms are dried at home. Beans and sauerkraut are often salted, and salt and vinegar are combined in making pickles, such as cucumber pickles.

The first bottling was done about 180 years ago. In bottling and canning the food is heated to destroy spoilage organisms. In canning the container is sealed before it is heated; in bottling it is sealed afterwards. Bottling is cheaper because the bottles can be used again and again, but canned foods are more convenient for storage. At present bottling and canning are used for preserving a great variety of fruit and vegetables.