
EFFECTS OF ACIDIFICATION ON PE ACTIVITY, COLOR AND ANTIOXIDANT PROPERTIES OF COLD BREAK TOMATO JUICE
Author(s) -
SARR FALLOU,
TSAI PIJEN
Publication year - 2008
Publication title -
journal of food quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.568
H-Index - 43
eISSN - 1745-4557
pISSN - 0146-9428
DOI - 10.1111/j.1745-4557.2007.00182.x
Subject(s) - chemistry , food science , antioxidant , butylated hydroxyanisole , lycopene , polyphenol , ferric , pectin , carotenoid , biochemistry , organic chemistry
Turbidity maintenance, high antioxidant activity and attractive red color are important attributes of good tomato juice. Acidification was found effective in pectin esterase (PE) inactivation and turbidity maintenance. However, no information related to the changes of antioxidant properties after enzyme inactivation by acidification has been reported. In this article, acidification of cold break tomato juice to pH 2 or 3 was conducted after extraction. The changes of antioxidant properties (content and activity) and their correlation with PE activity and color in the juice were studied. Results indicated that acidification enhanced the viscosity of tomato juice by decreasing its PE activity. Significant increases of the main antioxidant contents (lycopene, polyphenols and vitamin C) and antioxidant activities (1,1‐diphenyl‐2‐picrylhydrazyl scavenging, ferrous ion chelating ability [FICA] and reducing power), as well as red color, were also found. In addition, the acidified cold break tomato juice exhibited better FICA and reducing power than butylated hydroxyanisole and α ‐tocopherol. This finding reveals the possibility of producing tomato juice with high antioxidant capacities by acidification.PRACTICAL APPLICATIONS The consumers' demand for healthy products with high quality toward fresh and health has increased remarkably these years. Tomato is one of the most popular vegetable juices, and its important quality aspects are color, stability and antioxidant capacity. Pectin esterase is the principal agent responsible for tomato juice stability. In addition, the goal of tomato juice processors is to optimize processing conditions by prevention of heat and oxidative damages on antioxidant components. Our results indicated that acidification may stabilize tomato juice and improve its color characteristics and main nutritional factors. Therefore, the acidification treatment could be used as a tool for providing the attractive color and enhancing the nutritional value and health‐promoting properties of cold break tomato juice.