Investigation of the quality of refined soybean oil after the short-term domestic frying process of breading nuggets

Abstract

Frying is one of the most attractive food preparation techniques and has been in use for centuries. It refers to a gastronomic practice that is widely accepted around the world and used both in the industrial area and domestically. It is worth noting that this preference of consumers for fried foods is due to their unique sensory properties, such as taste, aroma and texture. However, with the high temperature that is used in the cooking method, the chemical composition of the frying oil can be modified. The reactions that occur in vegetable oils during frying (hydrolytic processes) are associated with several mechanisms, such as reactive species, chemical formation of the lipid, medium and method, inducing the speed and nature of frying. The purpose of this work is to investigate the characteristics of the vegetable oil most used by the population (refined soybean oils) used in the domestic method of short-term frying, using the electric fryer for domestic use and conventional method. Nugget-type breaded products were used because they are a convenient product, widely consumed in industrialized countries. Short-term domestic frying was done over the course of three days, with a period of one week. After each frying, the refined oil was researched. The methodology is based on bromatological evaluations of quality research using acidity analyses, where the content of free acidity, compounds formed by hydrolytic rancidity, was verified. According to the results, the samples of fresh soybean oil were within the regulatory limits. However, soon after the short-term frying process, there was an increase in the free fatty acid content of both short-term domestic frying using soybean oil. In addition, there was no considerable difference in the increase in the value of fatty acids in relation to both domestic frying techniques. However, as a rule, the oil showed an excellent thermal quality, bromatological analyses showed that it is necessary to be cautious when reusing short-term frying oils. It is analyzed that the electric fryer is efficient in the quality of the oil in terms of preservation in contrast to the conventional method, possibly for the reason of temperature control and better sealing effectiveness.