Knowing the state of public opinion regarding a product, the reputation of a celebrity or the assessment of a political candidate is very useful in today's world. For example, in the particular case of a company, analyzing the opinions of its customers is very beneficial, since it allows to know the disconformities and, from these, to define new strategies that guarantee to obtain a greater degree of satisfaction in the users, as well as a greater success within the market. This article aims to develop a method for classifying the polarity of product aspects.