Effect of high pressure homogenization (HPH) on the physical stability of tomato juice

High pressure homogenization (HPH) is a non-thermal technology that has been widely studied as a partial or total substitute for thermal food processing. Although the aspect of microbial inactivation has been widely studied, there are only a few works in the literature dealing with the physical-chemical changes in fruit products due to HPH, especially regarding its rheological properties. The present work evaluated the effect of HPH (up to 100 MPa) on the physical stability of tomato juice. HPH changed the tomato juice particle size distribution (PSD), pulp sedimentation behavior, serum cloudiness (turbidity), color and microstructure, by disrupting the suspended pulp particles. It therefore increased juice stability to sedimentation and changed its color due to leakage of lycopene from the disrupted cells. The effect of homogenization pressure on the physical properties of the juice followed an asymptotic behavior. The results indicated that the HPH could be used as a valuable tool to promote desirable physical property changes in food products, such as increasing the consistency and reducing particle sedimentation and serum separation, hence improving sensory acceptance. (C) 2012 Elsevier Ltd. All rights reserved.