| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2086794 | Innovative Food Science & Emerging Technologies | 2013 | 10 Pages |
This study aimed to design, build and validate an ohmic heating apparatus in bench scale and evaluate its performance on liquid food processing. The equipment developed showed adequate performance, monitoring data and heating products satisfactorily. Three ohmic cells were developed and tested in the device. When acerola and blueberry pulps were heated in the ohmic heater, a nonlinear behavior of electrical conductivity with temperature was observed. This behavior is associated with bubble formation caused by water boiling due to temperature gradients inside the cells. This phenomenon is influenced by a number of factors, such as solids content, electric field strength, ohmic cell size and agitation. Two of the ohmic cells developed, when placed on agitating devices, are suitable for a uniform heat treatment of liquid foods. The ohmic heating apparatus developed is adequate to conduct studies to better understand this technology and its applications on food processing.Industrial relevanceThe apparatus of ohmic heating for liquid foods designed and tested in this work can be used to evaluate fundamental parameters, such as electrical conductivity of the product, heating time and process homogeneity. It also provides a tool to monitor processing effects on the quality of end products in order to find the best conditions for a continuous ohmic heating process in an industrial scale.
► This study aimed to design, build and validate an ohmic heater in laboratory scale. ► Acerola and blueberry pulps were used to evaluate the performance of the device. ► A non linear behavior of the electrical conductivity with temperature was observed. ► This linearity deviation is associated with bubble formation during heating. ► Bubbles were caused by water boiling due to temperature gradients inside the cells.
