Electrical Properties of Jaggery as a Function of Moisture Content: Implications for Quality Control and Shelf-Life Augmentation

Authors: Kohinoor Singh Bhullar; Gurveer Kaur; Ravinder Singh

Book: Transforming Food Analysis and Control: Non-Destructive Technologies and Innovations

Editors: K. Prasad, S. Shekhar, M. K. Paswan, and R. Ahuja

Publisher: SLIET Longowal

Publication year: 2026

Publication date: 2026-07-20

ISBN: 978-81-990304-1-1 (e-book); 978-81-990304-0-4 (hardback)

Chapter pages: 201–212

DOI: To be added after DOI registration.

Abstract

Jaggery, an uncentrifuged sugar product rich in essential minerals and bioactive compounds, represents a healthier alternative to refined sugar; however, its hygroscopic behaviour significantly compromises product quality and shelf life through moisture absorption and subsequent microbial degradation. The internal moisture content is the critical quality attribute governing its stability, yet the conventional hot air oven method for moisture determination is time-consuming and unsuitable for real-time industrial monitoring. This study addresses the need for a rapid, non-destructive quality assessment technique by examining the relationship between the physicochemical properties of solid jaggery and its electrical characteristics as a function of varying moisture levels. Plain jaggery samples were analysed using a custom-designed setup to measure electrical conductivity (σ), resistivity (ρ), resistance (R), and conductance (G) across a moisture range of 4.5% 7.58%. The results revealed a complex but consistent relationship between moisture and electrical properties, providing a basis for indirect moisture estimation. Electrical resistance and resistivity generally increased with higher moisture content, attributed to the insulating effect of entrapped air pores. In contrast, conductivity and conductance decreased until 6.67% moisture, beyond which conductivity exhibited an unexpected rise. Additionally, the study established a direct correlation between current flow and temperature elevation in the jaggery matrix, highlighting the influence of ionic resistance and moisture-filled pores on heat dissipation, an important aspect for ohmic heating applications. These findings lay a crucial foundation for developing an electrical resistivity based, real-time moisture measurement system, facilitating improved process control and enhanced shelf-life management of solid jaggery.

Keywords: Jaggery; Moisture content; Electrical conductivity; Resistivity; Non destructive testing; Quality assessment; Ohmic heating

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