Changes in phenolic profile and antioxidant activity during production of diced tomatoes

Food Chemistry (Impact Factor: 3.39). 06/2011; 126(4):1700. DOI: 10.1016/j.foodchem.2010.12.061


Tomatoes and tomato-based products are rich in antioxidants such as carotenoids, vitamin C and polyphenols. The industrial processing of diced tomatoes involves heat treatments in which these antioxidant compounds may be potentially affected. In this study, we evaluate the effect of each separate step in the dice-making process. Three technological processes were investigated: Hot. Cold and Cold treated with calcium salt (CaCl2). Four stages were monitored in each process: (1) fresh tomatoes: (2) peeled tomatoes: (3) diced tomatoes; and (4) final product after sauce addition. The main tool for minimising or counteracting the eventual processing damage was the strategy of 'reconstitution', achieved by adding a sauce rich in seeds and peels with high levels of antioxidants and phenolics to the diced tomatoes. Different analyses were carried out in order to evaluate the effect of each processing step. First, total polyphenols (TP) were evaluated using Folin-Ciocalteau (F-C) assay and antioxidant activity using ABTS(+) and DPPH assays. Flavonols, flavanones, hydroxycinnamic and phenolic acids were then quantified using liquid chromatography/electrospray ionisation tandem mass spectrometry (HPLC-ESI-MS/MS). The combination of principal component analysis (PCA) and analysis of variance (ANOVA) revealed that each processing step induces alterations in the antioxidant and phenolic profile, and in particular sauce addition and calcium treatment significantly affected the levels of antioxidants and phenolics during the dice-making process.

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Available from: Cristina Andres-Lacueva
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    • "foods containing phenolic compounds (flavonoids/hydroxycinnamic acids and esters) with high antioxidant activity and human health (Lila 2007; Ververidis et al. 2007; Han and Baik 2008; Cuevas-Rodriguez et al. 2010). The growing recognition of the importance of plant antioxidants in human health has thus led to increased research interest in the synthesis and accumulation of these antioxidant compounds in plants (Tamagnone et al. 1998; Hoffmann et al. 2004; Niggeweg et al. 2004; Abdulrazzak et al. 2006; Luo et al. 2008; Vallverdu-Queralt et al. 2011). Both academic and applied interest in this area is further stimulated by the fact that some widely consumed plants are relatively rich in flavonoid/phenolic compounds and by the observation that people who consume higher quantities of these foods appear to have lower risks for certain health problems, such as cardiovascular disease and cancer (Sawa et al. 1999; Bazzano et al. 2002; Clifford 2004; Cos et al. 2005; Go et al. 2005). "
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