ICDSUPL1-T001

Volume: 1, 2022
1^st International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: ENVIRONMENT  – PLANT  – ANIMAL  – PRODUCT

Abstract number: T001

DOI: https://doi.org/10.24326/ICDSUPL1.T001

Published online: 26 April 2022

ICDSUPL, 1, T001 (2022)

Electrical conductivity of sheep’s milk and its mixtures

Jakub Biegalski¹*, Dorota Cais-Sokolińska¹

^{1 Department of Dairy and Process Engineering, Poznań University of Life Sciences, Wojska Polskiego 31, 60-624 Poznań, PolandAffiliation}

^{* Correspondence author: jakub.biegalski@up.poznan.pl}

Abstract

Electrical conduction properties of any material is a representation of capability to support an electric current. Electrical conductivity (EC) is characteristic for the matrix and depends on the concentration of anions and cations. EC measurement is most often used to assess the degree of milk acidification (due to the conversion of lactose – non-electrolyte into lactic acid – electrolyte), milk adulterated with the addition of sodium bicarbonate, milk from cows with mastitis (due to increased chloride concentration). Generally speaking, the intense increase in EC occurs as a result of changes in the colloidal system during acidification, the formation of a network of casein micelles, and changes in the solubility of colloidal calcium and phosphorus. Since recently a greater interest in dairy products with even a partial share of sheep’s milk has been observed, a hypothesis was put forward: EC measurement may be important in assessing the suitability of sheep’s and cow’s milk mixtures for processing and in identifying the proportion of sheep’s milk in this mixtures. The research material was mixtures of fresh sheep’s milk (S) combined in the proportion of 10:90, 20:80, 30:70, 40:60 and 50:50 with fresh cow’s (C) milk (v/v). Additionally, the EC of mare’s milk and goat’s milk as well as their mixtures with sheep’s milk (50:50) were measured. EC was measured (n = 5) using a CP–402 conductivity-meter equipped with EC–60 electrode (Elmetron, Zabrze, Poland). Statistical analysis was carried out using TIBCO Statistica data analysis software, version 13.3 (TIBCO Software Inc., Palo Alto, CA, USA). As a result of the research, it was shown that the conductivity of sheep’s milk (4.389 mS/cm) is higher than that of cow’s milk (2.294 mS/cm, P<0.05). Only 30% of sheep’s milk in the mixture increases the EC in comparison to cow’s milk (P<0.05). When analysing the EC of S milk, it is worth noting that it is also greater than the EC of mare’s milk (M) (approx. 3.972 mS/cm) but lower than the EC of goat’s milk (G) (5.238 mS/cm). On the basis of the research, the usefulness of the EC measurement for characterizing the properties of milk other than cow’s milk, as well as for determining the proportion of sheep’s milk in the mixture with cow’s milk was proved..

How to cite

J. Biegalski, D. Cais-Sokolińska, 2022. Electrical conductivity of sheep’s milk and its mixtures. In: 1st International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL1/T001