The Science Behind the Hot Dog

Have you ever read the ingredients list on a package of hot dogs or lunch meat and found yourself wondering, “What’s this doing in here?”  Many processed meat products contain ingredients both familiar (e.g., pork, beef, sugar, salt) and unfamiliar to consumers.  Unfortunately, some consumers are turned away by ingredients that sound more like they belong in science labs than in kitchens.  However, these compounds are used to increase the quality and safety of products while keeping them affordable and accessible to the consumer (Why ship something that will spoil en route?).  So to answer your question of, “What’s this doing in here?”, here are the purposes of several components found in many processed meat products explained.

       

               

Sodium Phosphates

·         “Phosphates” can encompass a variety of compounds including mono-, di-, and triphosphates.

·         Whereas monophosphates act as buffering compounds, di- and triphosphates are used to increase the water-holding capacity in meat products (Aberle, Forrest, Gerrard, & Mills, 2001).

o   Increased water-holding capacity leads to products with greater tenderness and juiciness (Aberle et al., 2001).

o   These phosphate compounds act similarly to adenosine triphosphate (ATP), the major energy unit produced in most living things.

·         Phosphates may also deter the development of rancidity and improve product texture (Aberle et al., 2001).

Sodium Lactate

·         This weak acid is added to processed meats to control the growth of Listeria monocytogenes, a bacterium of concern in the world of processed, packaged foods (Zink, N.A.). 

·         Sodium lactate is able to disrupt the pH gradients that bacteria set up in their cellular membranes.  These gradients are vital for energy-producing machinery to work, so disruption of the gradient severely reduces a bacterium’s ability to thrive (Zink, N.A.).

Sodium lactate

Sodium Diacetate

·         Sodium diacetate is also added to meat to reduce the growth of L. monocytogenes (Zink, N.A.).

·         This compound dissociates into acetic acid (the active ingredient in vinegar) and sodium acetate.  Acetic acid can donate protons to the environment, thus lowering pH.  This action disrupts the proton gradient and weakens a bacterium’s ability to survive (Zink, N.A.).

Sodium diacetate

Sodium Ascorbate/Erythorbate

·         Sodium ascorbate and erythorbate are “isomers;” that is, their atomic makeup is the same but their conformations are different. 

·         Sodium ascorbate is naturally found in citrus fruits and vegetables, and its biologically active form, ascorbic acid, is commonly known as vitamin C (NCBI, N.A.).

·         Sodium erythorbate is more commonly used in processed meats since it is cheaper and its pH is much closer to that of meat (Mancini et al., 2007).

·         Both sodium ascorbate and sodium erythorbate act as cure accelerators: they reduce the amount of time needed for a product treated with nitrite to develop cured properties (Aberle, 2001).

So don’t fear those scientific-sounding ingredients on the back of a package.  Those ingredients are added with the consumer’s safety and satisfaction in mind.  Keep enjoying those hot dogs and brats at grill-outs this summer, and stock up on lunch meat for kids heading back to school.

References

Aberle, E.D., Forrest, J.C., Gerrard, D.E., & Mills, E.W. (Eds.).  (2001).  Principles of Meat Science (4^th ed.). Dubuque, IA: Kendall/Hunt Publishing Company.

Mancini, R.A., Hunt, M.C., Seyfert, M., Kropf, D.H., Hachmeister, K.A., Herald, T.J., Johnson, D.E.  (2007). Comparison of ascorbic acid and sodium erythorbate: Effects on the 24 h display colour of beef lumbar vertebrae and longissimus lumborum packaged in high-oxygen modified atmospheres.  Meat Science 75(1), 39-43.

NCBI (N.A.).  Ascorbic Acid—Compound Summary (CID 23667548).  Retrieved from http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=23667548&loc=ec_rcs#itabs-2d.

Zink, D.L.  (N.A.).  Post-processing interventions to control listeriosis  [PDF].  Retrieved from http://www.fsis.usda.gov/wps/wcm/connect/3ceeab5b-0bed-4bf6-8513-05f79df03e2b/Listeria_DZink_12.pdf?MOD=AJPERES&CACHEID=d548190c-c5e0-49ba-8771-52a14f42b830.

All compound images are courtesy of PubChem (http://pubchem.ncbi.nlm.nih.gov/).