Mathematical models for correlating electrical parameters and milk adulterants

Abstract

This work presents mathematical models obtained from electrical measurements to control of milk quality and detection of adulterations, especially by ethanol, sodium chloride and sodium bicarbonate. These substances may cause changes in the electrical properties of raw milk. Electrical measurements are non-destructive and fast techniques. The proposed models correlate the addition of the mentioned substances with measurements of conductance and phase angle at a fixed frequency of 100 Hz. Linear models were proposed from the data and the independence, normality, lack of adjustment and homoscedasticity were verified. The detection limits obtained based on conductance were 0.01 %, 0.03 g/L and 2.1 g/L for samples adulterated with ethanol, sodium chloride and sodium bicarbonate, respectively. The limits for measurements based on the phase angle were 0.4%, 1.3 g/L and 16.4 g/L, respectively. The results demonstrated that the proposed models may be a powerful tool to improve milk analysis methodologies.

Study of Quality Factor (Q) and Phase Angle (θ) obtained per electrical impedance to characterization and detection adulteration in honey.

“…The Q parameter appears as a good alternative of electrical property to be used in methodologies. In future work will be carried out with a focus on statistical validation of the models proposed, with a larger number of samples and tests such as assumptions of normality, homoscedasticity and independence of the data, along with the calculation of the model's lack of fit test, detection limits (LOD) and quantification (LOQ), similar to what has been done in other works with other foods [10]. Other possibilities of methodologies based on these electrical measures will also be studied, such as exploring specific frequency ranges, in addition to evaluating other quantities related to EIS with potential to be used.…”

“…Thus, it is necessary to develop methods to ensure the quality of honey, guaranteeing that the consumer obtains a genuine product. The determination of electrical measurements appears as an alternative, due to practicality, as they are non-destructive and generally low-cost methods [10]. This technique has been applied as a method for quality control and detection of adulterations in other foods, such as milk [11,12].…”

Escaneamento Por Bioimpedância Elétrica Em Leite: Explorando a Técnica

“…O leite pode ser comercializado na forma cru ou "in natura", ou após sofrer processo térmico de pasteurização ou UHT, segundo as normativas contidas nas portarias n° 146/1996 e n° 370/1997 do MAPA (BRASIL, 1996;BRASIL, 1997 Percebe-se a busca pela otimização das pesquisas com impedância em análise de leite, pelo fato de oito trabalhos estarem usando equipamentos comerciais (LIU et al, 2015;LI et al, 2016;BANCALARI et al, 2016;TRIPATHY et al, 2017;DAS et al, 2018;SCHUMACHER et al, 2019;NASCIMENTO et al, 2020;SOARES et al, 2020), enquanto que quatro apresentaram resultados de equipamentos de desenvolvimento próprio ou com adaptações. Na avaliação da qualidade do leite bovino cru, os teores de proteína e gordura são os responsáveis por aumentar o valor agregado (RENTERO, 2018).…”

Escaneamento Por Bioimpedância Elétrica Em Leite: Explorando a Técnica

“…Percebe-se a busca pela otimização das pesquisas com impedância em análise de leite, pelo fato de oito trabalhos estarem usando equipamentos comerciais (LIU et al, 2015;LI et al, 2016;BANCALARI et al, 2016;TRIPATHY et al, 2017;DAS et al, 2018;SCHUMACHER et al, 2019;NASCIMENTO et al, 2020;SOARES et al, 2020), enquanto que quatro apresentaram resultados de equipamentos de desenvolvimento próprio ou com adaptações.…”