Process of canning effects on vegetables

From the textural standpoint, vegetables may be divided into those that are eaten raw and valued primarily for their crispness, those that are eaten cooked and valued for their softness and those that can be consumed in either form such as cauliflower and carrots.

Vegetables like peas, beans, greens are sometimes canned. The retention of original color is of great importance effecting the marketability and consumer response.

In the process of canning, vegetables are heated to destroy spoilage disease causing microorganisms.

Such heat treatments also produce a number of of undesirable chemical and textural changes in the vegetables. The textural changes are due to partial destruction of the cell wall and cell membrane.

Blanching, plus the strong heat treatments applied to nonacid vegetables, appears to be responsible for the large vitamin losses in canning.

Heat treatments also cause chemical alteration of the green pigment chlorophyll, thus resulting in a processed vegetable with less green color.

During canning chlorophyll gets converted to pheophytin due to the high temperature used. Sometimes to retain the color and to neutralize the acid, alkali is added.
Process of canning effects on vegetables

Preservation to maintain food quality

The deterioration of food quality occurs due to various physical, chemical, enzymic or microbiological factors.

Food preservation is the process of treating and handling food to stop or greatly slow down food spoilage. A number of preservation techniques are available for maintaining food quality, which act by slowing or reducing microbial growth.

Among food preservation methods are include: canning, pickling, drying and freeze-drying, irradiation, pasteurization, smoking, and the addition of chemical additives.

Thermal processes with high heat transfer rates from heating source to the food result in better quality. The traditional method of sterilization and the aseptic method are commonly and predominant thermal processing techniques for commercial sterilization of canned foods.

The packaging of food is typically designed to maintain the quality of food products during storage, transportation and end use. It prevents quality deterioration, and facilitates distribution and marketing efficiencies.

Through the correct selection of both materials and packaging technology, food freshness can be maintained to obtain the required shelf life.
Preservation to maintain food quality