Drying is the most frequently used method; however, two other methods are becoming increasingly common: freezing and preserving in hermetically sealed containers by sterilizing or pasteurising. Moreover, advances in food processing technology have led to the development of convenience foods, especially ready-to-cook products, which simply require thermal treatment, and ready-to-heat and ready-to-eat foods (Sloan, 2005). The methods of preservation mentioned above are part of this trend.