Comparative analysis of ohmic heating and conventional evaporation for milk concentration: Quality parameters, energy and exergy efficiencies, GHG emission, and sensory evaluation

Darvishi, Hosain; Mohammadi, Mobin; Behroozi-Khazaei, Nasser; Jahani-Azizabadi, Hossein; Solaimani, Moslem

doi:10.22104/ift.2025.7710.2222

Comparative analysis of ohmic heating and conventional evaporation for milk concentration: Quality parameters, energy and exergy efficiencies, GHG emission, and sensory evaluation

Document Type : Research Article

Authors

¹ Department of Biosystems Engineering; Faculty of Agriculture; University of Kurdistan, Sanandaj, Kurdistan, Iran

² Department of Animal Science; Faculty of Agriculture; University of Kurdistan, Sanandaj, Kurdistan, Iran

10.22104/ift.2025.7710.2222

Abstract

This study presents a comparative analysis of ohmic and conventional heating methods for milk concentration, evaluating processing kinetics, energy-exergy efficiency, quality parameters, environmental footprint, and sensory attributes. Ohmic heating outperformed conventional methods, slashing processing time by 1.88–4.33times and reducing energy consumption by 10.5–17 times, while achieving remarkably higher energy and exergy efficiencies (42.71–57.79% and 9.48–12.75%, respectively) compared to conventional heating (5.42% and 1.18%). Notably, ohmic heating led to less significant pH alterations (3.87 - 6.97%) compared to conventional heating method (10.37%). However, ohmic heating did induce more pronounced changes in color. Sensory attributes identified 20 V/cm as the best voltage gradient for balancing taste, texture, and aroma. Crucially, ohmic heating reduced CO2 emissions by 90.3–95.6% relative to conventional heating. These results establish ohmic heating as a sustainable, energy-efficient alternative for industrial milk concentration, addressing critical challenges in food processing sustainability without compromising product quality.

Graphical Abstract

Highlights

Ohmic heating saved 10.5 to 17 times energy consumption.
Ohmic heating preserves pH better but causes more color changes.
20 V/cm ideal for ohmic heating; higher voltages had negative effects on sensory evaluation.

Keywords

Main Subjects

Dairy technology

References

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