Science Buddies: "Ask an Expert"

how fast does salmonella grow?
does growth of salmonella mean sodium nitrite has failed its purpose to prevent spoilage?
do you think having an additional food preservative can help inhibit growth of salmonella on raw meat?

Hi Chandlersbing,

Welcome to Science Buddies! Are you doing an experiment along the lines of what is most effective at inhibiting salmonella growth? The rate of Salmonella growth depends on a variety of factors, such as temperature and pH. The bacterium’s quickest growth occurs over 7-48 degrees Celsius and between a pH of 6.5-7.5. Different scientific experiments yield different measures in growth rate of Salmonella depending on whether they used agar, the type of strain, how long they let it grow, the type of environment, etc. I suggest that you do a specific Google search, such as “Salmonella growth as a function of temperature”, depending on what your independent variable is. What are you changing to affect the growth rate of Salmonella? Sodium Nitrite is generally thought of as ineffective at controlling the growth of Salmonella. Instead, other food preservatives, such as organic acids (potassium sorbate with lactic acid and citric acid) are used as preservatives against salmonella growth, for example in sausages. Simply, salt and sugar are used as preservatives against spoilage and work against Salmonella by “dehydrating” it through osmosis.

I hope that you find this information helpful and let me know if you have any more questions about your project.

~Catherine M.

Thank you and i have used this info! ♡

I have a project on using Zinc as an additional preservative specifically to raw meat since raw meat don't contain Sodium Nitrite like sausages. I hope all goes well!