CHARACTERISATION OF TOMATO JUICE AND DIFFERENT TOMATO-BASED JUICE BLENDS FORTIFIED WITH ISOMERISED LYCOPENE EXTRACT

Abstract

Juices and beverages with bioactive compounds are consumed for their nutritive and health benefits. Beverages fortified with various functional ingredients are an important product category within the functional food segment. In this study tomato juice with various proportions of apple, carrot and sweet corn juice together with isomerised lycopene extract were used for formulation of functional beverages. Chemical composition and physicochemical properties of prepared juice blends was evaluated and a sensory analysis was conducted in order to identify the most acceptable blends. The addition of concentrated isomerised lycopene extract with beta-carotene to tomato juice as well as juice blends significantly increased the levels of lycopene and especially the levels of cis-lycopene in the final products. The content of total lycopene in the juice blends varied from 16.21 mg/100 g to 25.65 mg/100 g, whereas the content of cis-lycopene – from 9.16 to 14.46 mg/100 g. The juice blends containing apple juice had the lowest pH and the highest titratable acidity. Higher percentage of apple, sweet corn or carrot juice in the blends resulted in higher contents of TSS in the functional beverage. The addition of apple, carrot, and sweet corn juice significantly changed the initial color of the tomato juice. The lowest colour difference (E) values had tomato-carrot juice blends (6.8–7.3), whereas the highest E had tomato juice with 25 and 35 % of sweet corn juice (10.6 and 14.3, respectively). Sensory evaluation revealed that the most acceptable taste had tomato-apple juice blend with 35 % apple juice and tomato-carrot juice blend with 40 % carrot juice.

Keywords: functional foods, juice blends, lycopene extract, sensory properties, tomato.

Article DOI: http://doi.org/10.15544/RD.2015.029