Development and Evaluation of an Impedance Spectroscopy Sensor to Assess Cooking Oil Quality

Abstract

Abstract-When the cooking oil is used repeatedly, several unwanted substances are generated, which may cause health problems. This study was conducted to determine the possibility of using the impedance spectroscopy to differentiate among varying cooking oil quality at various intervals of heating time at constant temperature. The frequency has started from 100 Hz to 100kHz. Fresh, 10-hour, 20-hour, 30-hour, and 40-hour heated cooking oil was prepared by using lab oven at temperature of 180oC. In this study, a sensing probe was designed to measure the electrical properties of the oil samples. The oil samples were analyzed using a viscometer to measure the viscosity of the oil, a sensor to measure total polar compound (TPC), and an impedance probe connected to a LCR meter to measure the electrical properties of the oil. The measurements were analyzed and correlated with oil quality parameters obtained from a viscometer and a sensor of TPC. The discrimination between different heated hours of oil samples was examined and the results were compared to their physico-chemical properties such as viscosity and total polar compounds. The effect of heating of frying oils were successfully evaluated and discriminated using the impedance spectroscopy. Significant correlations (r -0.98472) were found between changes in total polar compound properties of oil and the impedance values.

Frying Oil Evaluation by a Portable Sensor Based on Dielectric Constant Measurement

“…The basic principle was to analyze the dielectric constant of frying oil via a capacitive sensor. Several research groups have attempted to develop capacitive sensors for frying oil using various smaller devices [30][31][32], but challenges included either the inevitability of parasitic capacitance [30] or the signal processing device being too bulky and expensive (i.e., LCR meter [31][32][33]).…”

Electrical Impedance Spectroscopy for Quality Assessment of Meat and Fish: A Review on Basic Principles, Measurement Methods, and Recent Advances

“…According to the biological objects, application of EIS can be divided into three aspects, that is, electrical impedance tomography in medical imaging [2][3][4], quality and safety assessment in food industry, and phytophysiology in agronomy [5][6][7]. Research objects and targets of EIS applied in food are abundant and extensive, including for fruits, such as study on dry matter content of durian [8] and ripening of banana [9], for vegetables, such as changes in potato and spinach tissues during or after heating [10,11] and moisture content of carrot slices during drying [12], for meat, such as quality evaluation of pork meat during storage [13] and investigation of beef meat behavior during ageing [14], for chicken, such as discrimination of fresh and frozen-thawed chicken breast muscles [15], for fish, such as salt and moisture content determination of salted rainbow trout [16] and freshness estimation of carp [17], for dairy products, such as real-time detection of bovine milk adulteration [18], and moreover for determination of the additives content in natural juices [19], fermentation process of bread dough [20], and quality assessment of cooking oil [21]. Nowadays customers pay more attentions on quality attributes of meat products, such as appearance, flavor, and nutrients.…”

Degradation Monitoring of Repeated Cooking Oil Using Capacitive Inter-digital Electrode(IDE) Sensor

“…The heating time for all samples was range from 0 to 15minutes for each session. All samples were heated at 180 ± 3⁰C as recommended by [13]. About 200 grams French fries was fried for every session.…”

“…As reported in [10][11][12][13][14][15][16][17][18], an influence of oil quality on the frequency dependence of the dielectric property was used to gather basic data to support the quality assessment system of oil in the fried food industry. Therefore, the purpose of this work is to characterize an IDE sensor suitability for monitoring the degradation of frying oil after certain repeating number usage in a very low cost.The performance result of IDE sensor against the frying oil will be used as reference to interface with a controller system for portable device application in future.…”