Stability and usage of nitrogen in fats and oils

Abstract

The oxidative rancidity is, without a doubt, the main cause of the deterioration of fats and oils, and defines the shelf life of this type of products. Therefore, the stability (resistance against oxidation) has come to be one of the factors which worry the processors the most, thus it is also one of the main quality criteria. Rancidity chemical principles, its consequences, forms to prevent and the evaluation methods will be shortly discussed. Several factors determinate the stability of fats and oils, pointing out the chemical composition and the processing conditions. All the process steps must be accomplished searching a greater stability, for which some minimal cares must be observed. Particularly important in this sense are the steps of bleaching and deodorization. The usage of antioxidants and nitrogen represent valuable tools to improve oxidative stability, mainly in oils of unfavorable characteristics and composition.