Assessment of the Bio Preservative Potential of Selected Spices on Tomato Puree in Various Combinations Exhibiting High Antimicrobial Activity

Tomato puree is prone to spoilage due to its high water activity and near-neutral pH. Clean-label demand has generated renewed interest in spice-based preservatives. To test the most antimicrobial spices and spice combinations identified in previous in vitro screening (clove, cinnamon, and garlic used individually, clove and cinnamon, garlic and ginger, turmeric and ginger, cumin and garlic and ginger used in combination), we added them to tomato puree, and monitored it for 28 days at 4 °C. The control treatment, which did not receive any spice or spice combination, exceeded the 5 log CFU g^-1 spoilage limit after only 14 days, with a 9.4 log CFU g^-1 count of spoilage by lactic acid bacteria (10.8 log CFU g^-1 spoilage) and a one-third (6.1 mg/100 g ? 4.0 mg/100 g) reduction in the lycopene content from day 0 to day 21, with unacceptable sensory evaluation scores after day 21. The best single agent used was garlic (4.3 log CFU g^-1 spoilage by day 28); the clove + cinnamon and garlic + ginger combinations kept (4.1 log CFU g^-1 spoilage at day 28); stabilized the pH and acidity of the product; and preserved the lycopene and the red color. The majority of the interactions between spices were additively interacting; the turmeric + ginger interactions were synergistic; and the clove + cinnamon combination was the most acceptable; while the garlic-rich spice compositions decreased aroma and taste. These multiple-dose-sparing spice blends extended the acceptable shelf life of tomato puree from 7–10 days to 28 days, providing for the effective biopreservation of tomato puree.