Differences in antioxidant activity, total phenolic and flavonoid contents of commercial and homemade tomato pastes

Abstract

Tomato paste is an important industrial product of food industry, which has been also produced in the homes of tomato producing countries. Although literature on the physical and chemical composition of commercial and homemade types of tomato pastes is available, studies on their antioxidant activity (ABTS), total phenolic content (TPC) and total flavonoid content (TFC) are inexistent. The aim of this study is to compare the TPC, TFC and ABTS values of homemade and commercial types of tomato pastes, as well as their pH, brix and color values. Commercial (n = 9) and homemade (n = 6) tomato pastes were obtained from either national markets or homes that produce tomato pastes in various cities of Turkey. The TPC and TFC values of commercial tomato pastes were 209.62 ± 17.02 mg gallic acid equivalent (GAE) and 42.52 ± 4.85 mg catechin equivalent (CE), respectively, and they were significantly higher (p < 0.05) than those of homemade counterparts, which had the TPC and TFC values of 112.25 ± 53.01 mg GAE and 34.24 ± 8.60 mg CE/100 g, respectively. Moreover, the antioxidant activity of commercial tomato pastes (615.99 ± 227.43 μmol TE/100 g) was significantly higher (p < 0.05) than that of homemade tomato pastes (267.39 ± 220.79 μmol TE/100 g). Insignificant differences in CIELAB color values were found between commercial and homemade tomato samples while variations in brix values of homemade samples were higher than those of commercial samples. Results indicated that because commercial tomato pastes are produced under controlled conditions in comparison to homemade counterparts, former ones have a superior quality in terms of their TPC, TFC and antioxidant values.

Keywords

• Tomato paste
• Total phenolic
• Flavonoids
• Antioxidant activity