Reduction in microbial load of tomato paste using onion solid wastes extract as an partial alternative to sodium benzoate

In this study, extracts from onion solid wastes were prepared and added to tomato paste in different concentrations (1000, 2000,5000 ppm). Tomato paste was stored under room temperature for (0.5, 1, 2, 4, 6, 8 and 12 months). Microbial load (total aerobic bacteria count, total mold, and yeast count) of tomato paste samples was studied after storage. The results showed that addition of onion wastes' extract at 5000ppm reduced aerobic bacteria load by (1.06 log CFU/gf), and the molds and yeasts by (1.37 log CFU/gf) before storage. After storage for 12 months, the increase in microbial load was the lowest in this sample and it reaches (0.91 log CFU/gf) for the aerobic bacteria, and (0.81 log CFU/gf) for the molds and yeasts. The possibility of using onion wastes' extract (5000ppm) as an alternative to sodium benzoate was studied. The results showed the possibility to reduce the percentage of added sodium benzoate from 0.1% to 0.07% while keeping the total bacteria count within the acceptable level after storage for 12 months..