Techniques of food preservation

Overview
Conservation is generally defined as a method used to preserve a status quo or to prevent impairment may be caused by chemical (oxidation), physical (temperature, light) or biological (microorganisms). The rate of deterioration depends on the properties' intrinsic 'related to the food and conditions "extrinsic" which are related to the environment.
The conditions are intrinsic and extrinsic barriers (or barriers) to the growth of microorganisms or mechanisms of non-microbial alteration. The techniques of food preservation are based on the exploitation of the principle barriers to preserve the quality and food safety.
The techniques of food preservation can be classified into three groups: physical, physico-chemical or microbiological. The first group of these techniques involves physical processes such as temperature, pressure, ionizing radiation and the electric field. The second group is based on the modification of intrinsic characteristics of the food such as pH, water activity or the incorporation of additives in food for its conservation. The last group is based on the use of microorganisms for the modification of physico-chemical characteristics of the food, the technique is best known fermentation.
The combination of conservation techniques can also be envisaged to increase the shelf life of food without causing a significant change in its sensory and nutritional characteristics.
Content
The various techniques of food preservation addressed in this document are:
- Food preservation by cold
- Food preservation by heat treatment
- Food conservation by reducing water activity
- Food preservation by reducing the pH
- Food preservation by smoking
- Food preservation by controlling the Redox potential
- Food preservation by ionizing radiation
- Food preservation by high pressure
- Food Preservation by pulsed electric field
- Chemical food preservation
- Food preservation by combination of several techniques
