Characterization of the Interactions of Solubilized Proteins in Processed Meat Formulations

Non-Technical Summary: There is a current trend in the food industry to find ways to increase the healthiness of food products by reducing or minimizing sodium chloride (salt) intake. In addition, for a small segment of the public (e.g., those suffering from CKD or chronic kidney disease), products with added phosphates are also considered a health detriment (Block GA and others 1998, Drueke and Foley 2006, Goodman and others 2004, Ibel and others 1978, Krestenbaum and others 2005, Kramer and others 2005, Ketteler and Giachelli 2006, Schwarz and others 2006, Tonelli and Pfefer 2007, Tonelli and others 2005). It is in the best interest of the food industry to try and meet the needs of all consumers by providing products with minimal negative health impacts. This project attempts to address these concerns by looking at an alternative means to improve protein functionality by minimizing additives that may have negative health implications for some consumers. <P> Approach: Purge and Color study: On a lab-scale, USDA select striploins will be obtained from a commercial processor. Steaks will be transported to OSU for treatment. Treatment will involve injection of striploins using a handheld injector with pump to 110% of their green (initial) weight with 6 treatments. Treatments will include: 1% NH4OH, 1% NH4OH with 0.45% phosphate, 1% NH4OH with 1% phosphate, 10% NH4OH, 10% NH4OH with 0.45% phosphate, 10% NH4OH with 1% phosphate, Water injection, Control (4.5% phosphate). All treatment solutions will contain 3.6% NaCl and 1% Rosemary. Loins will be cut into 2.54 cm steaks, package in a high oxygen modified atmosphere tray (80% O2; 20% CO2) and stored at 4 C for 4 d. Steaks will then be stored in a retail display case. Three randomly selected steaks will be measured for purge and pH after 0 h display. Color will be monitored until all steaks are color scored as unacceptable. Sensory evaluation will be conducted to determine whether there are off-flavors/odors. Full-scale ammonium hydroxide evaluation: Results from the initial studies will be used to select conditions for a full scale study. Striploins will then be randomly enhanced to 110% their green weight with the selected test treatment or the control commercial phosphate solution. Enhancement will be single injection and follow protocol as outlined by Vann and Mireles DeWitt (2007). Injected striploins will be cut into steaks at least 30 min after enhancement in order to give the striploins sufficient time to absorb the enhancement solution. Striploins will be cut, packaged and stored as previously indicated. Three steaks will be randomly collected on d 5 (straight from box, d 0 under retail lights), 12 (d 7 under retail lights), and 19 (d 14 under retail lights) to measure pH and Color (quantitative L*a*b*) in the raw steaks. Sheer Force will be measured using a Universal Instron testing machine with a Warner-Bratzler shear head attachment (Model 4502 Canton, MS) on steaks cooked to an internal temperature of 70 C. Proximate evaluation will be conducted on both raw and cooked steaks. Lipid oxidation by TBARs will be measured on the raw product. Aerobic plate counts will be evaluated on steaks. Sensory evaluation will be conducted at least on d 0 and d 7. All analysis will follow protocols as outlined by Vann and Mireles DeWitt (2007). All results will be analyzed using generalized least squares (PROC Mixed, SAS Inst. Inc., Cary, N.C., U.S.A.). The next stage of the project will be to investigate salt reduction in enhanced beef products. Iterations used to determine whether salt or phosphate usage can be reduced through incorporation of ammonium hydroxide in beef will be repeated using pork as a model. Furthermore, similar investigations will also be conducted on a processed meat product such as frankfurters.