ABSTRACT
Since ancient times, several techniques have been used to preserve fruits and their products: drying, concentration, freezing, fermentation, and chemical preservation by use of vinegar, wine, sugars, and spices. Thermal processing is relatively a more recent technique used for fruit preservation, but it has proven to be one of the most effective (Woodroof and Luh, 1986). Nicholas Appert, in 1809, was awarded a prize by the French government for developing a new method for heat preservation of food. The method has since been recognized as Appertization (named after Appert), sterilization, or more commonly, canning. Appert utilized his method to preserve more than 50 kinds of foods, some of which included fruits, vegetables, and meats. In the early stages of the method, food was filled into wide-mouthed glass bottles or jars and carefully corked, after which they were cooked in boiling water. The process time varied according to the product type. Although the method was successful in producing shelf-stable foods which did not undergo spoilage, the scientific basis for the preservation was not really known until almost half a century later, when another Frenchman, Louis Pasteur, discovered that food spoilage was caused by microorganisms which are destroyed at elevated temperatures. The technique which bears his name, pasteurization, as we know today, refers to a relatively mild heat treatment intended to destroy pathogenic microorganisms in foods, providing short-term extension of shelf life under refrigerated conditions.
