Publications in year 2013

Vol. 20, Issue 4



Effect of ultrasonic treatment on the colour stability of carrot juices

International Agrophysics
Year : 2013
Volumen : 20
Issue : 1
Pages : 161 - 171
  PDF 359.7 KB
Authors: Paweł Sakowski1, Emilia Janiszewska1

1Department of Food Engineering and Process Management, Faculty of Food Science, SGGW – Warsaw University of Life Sciences ul. Nowoursynowska 159C, 02-776 Warszawa
Abstract :

Ultrasound is a new method that has been used in the food industry for acceleration of unit operations such as drying, extraction and freezing. Sonication, despite its small invasiveness, has an effect on various physical, chemical and biochemical changes occurring in the materials. Colour is a very important parameter describing food, and a quality discriminant for the consumer and producer. The study investigated the effect of a 30-minute ultrasound treatment with a frequency of 21 kHz on the colour parameters changes of carrot juices from two producers with concentrations of 9, 12 and 21°Brix. The colour was measured in the L*a*b* system with calculation of the absolute colour difference, change in saturation, and tone (hue) of colour. There was no clear effect of extract content on the change of colour of juices treated with ultrasound. It was found that the juice extract from manufacturer A at 21°Brix and juice from manufacturer B with 12°Brix extract were characterised by the highest stability to the ultrasound. Juice colour changes after application of ultrasound were not detectable by the human eye. There were also no significant changes in the difference in colour saturation and tone between juices before and after sonication.

Keywords : carrot juice, colour, ultrasound
Language : Polish