Irradiation and the Nutritional Value of Beef

Hard

Does irradiating beef change its protein or fat content? Food irradiation is used to kill bacteria and extend shelf life. This project tests whether the process also changes the nutrients in the meat. You measure the protein and nitrogen content of irradiated and nonirradiated beef patties using a Licos combustion analyzer. Then you measure lipid (fat) content through a titration process with hexane and sodium hydroxide. The protein and nitrogen analysis tells you whether irradiation affects the building blocks of the meat. The lipid titration reveals whether the fat content changes. Together, these two tests give a clear picture of any nutritional differences.

Hypothesis

The hypothesis is that the irradiated beef and nonirradiated beef will have the same amount of protein and nitrogen level of nutrients, and that the nutritional value of lipids in the irradiated beef will be less than in nonirradiated beef.

Science Concepts Learned

Food Irradiation

Energy beams kill bacteria in meat — but do they also alter what the meat is made of? This project compares irradiated and nonirradiated beef patties to find out whether the process changes protein, nitrogen, or fat content. A Licos combustion analyzer measures the protein and nitrogen levels, while a titration with hexane and sodium hydroxide reveals any shifts in lipid content. Together, the two tests build a clear picture of whether the nutritional makeup of beef survives the irradiation process intact.

Macronutrients

Food irradiation kills bacteria in beef and extends shelf life, but does the process also break down the macronutrients inside? This experiment measures protein and fat content in irradiated and nonirradiated beef patties, using protein and nitrogen analysis alongside lipid titration to compare nutrient levels in treated and untreated meat.

Method & Materials

You will set up the Licos machine, analyze the protein and nitrogen content of the beef patties, and titrate the lipids in the beef patties.

You will need a nonirradiated ground beef patty, an irradiated ground beef patty, a Licos machine, 6 aluminum containers, 2 electronic balances, 6 40mL beakers, 5 125mL flourence flasks, 2 spatulas, 4 stirrers, 1 filter, 1 clamp, 1 burrette stand, 1 pippette, 100mL hexane, 200mL isobutyle alcohol, 125mL sodium hydroxide, and 8mL sulfuric acid.

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Results

Our investigation revealed that irradiation does have an effect on the nutritive value of beef. The protein and nitrogen content of the irradiated and nonirradiated beef patties were the same, but the lipid content of the irradiated beef was lower than that of the nonirradiated beef.

Why do this project?

This science project is interesting because it investigates the effects of irradiation on the nutritive value of beef, which is an important factor in food safety.

Also Consider

Variations to consider include investigating the effects of different levels of irradiation on the nutritive value of beef, or investigating the effects of different types of irradiation on the nutritive value of beef.