Abstract
Olive oil quality is normally assessed by chemical analysis as well as sensory analysis to detect the presence of organoleptic defects. Two of the most important parameters that define the quality of olive oil are the free acidity and the peroxide index. These chemical parameters are usually determinated by manual titration procedures that must be carried out in a laboratory by trained personnel. In this paper, a portable sensor system to evaluate the quality grade of olive oil is presented. The system is battery operated and characterized by small dimensions, a light weight and quick measurement response. The working principle is based on the measurement of the electrical conductance of an emulsion between a hydro-alcoholic solution and the olive oil sample. Tests have been carried out on a set of 17 olive oil samples. The results have shown how for fresh olive oil samples, the olive oil’s free acidity can be estimated from the electrical conductance of the emulsion. In the case of oxidized olive oil, the measured electrical conductance is also the function of the oxidation level, and a conductance threshold can be set to discriminate between extra virgin olive oils and lower-quality grade oils. The proposed system can be a low-cost alternative to standard laboratory analysis to evaluate the quality grade of olive oil.
Highlights
Olive oil is a vegetable lipid highly appreciated for its beneficial effects on human health [1]
Two of the most important parameters that define the quality of olive oil are free acidity, defined as the amount of fatty acids no longer linked to their parent triglyceride molecules, which is affected by the quality of the olives used to produce the oil as well as the production process, and the peroxide index, expressed as milliequivalents of active oxigen for a kg of oil, which is an indicator of the oil primary oxidation and is affected by the storage conditions [2]
The portable sensor system was used to evaluate the quality grade of a set of 17 olive oil samples (11 fresh olive oil samples characterized by a peroxide index 20)
Summary
Olive oil is a vegetable lipid highly appreciated for its beneficial effects on human health [1]. Olive oil quality is normally assessed by chemical analysis as well as sensory analysis to detect the presence of organoleptic defects. The official techniques for measuring these chemical parameters are manual titration procedures that must be carried out in a laboratory by trained personnel [3]. In the case of small industrial environments, such as olive oil mills and small packaging centers, which cannot afford an internal laboratory for quality analysis, the olive oil samples to be tested must be shipped to an external laboratory, and this results in high costs for the analysis and long response times. The development of simple and quick techniques for the analysis of quality grade of olive oil is important to allow in situ measurements directly in the industrial environment. A substantial research has been carried out in recent years towards the development of portable and low-cost sensor systems
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
