According to the 2015 National Beef Tenderness Survey (Martinez et al., 2017), top sirloin steaks destined for foodservice had lower consumer panel ratings for all sensory attributes and had higher shear force values than ribeye and top loin steaks. Blade tenderization can be used to improve the tenderness of top sirloin steaks (George-Evins et al., 2004), but it presents a food safety concern because pathogens can be translocated from the surface to the interior of the steak (Luchansky et al., 2008; Ray et al., 2010).
Sous vide cooking has been used by chefs in restaurants for many years. Several researchers have reported decreases in shear force values for beef muscles cooked utilizing sous vide (Hansen et al., 1995; Mortensen et al., 2012; Rinaldi et al., 2014; Vaudagna et al., 2002). Therefore, sous vide cooking might be an alternative way to ensure tenderness of foodservice cuts without blade tenderizing. Top sirloin steaks are one of the most economical steaks available on many foodservice menus, but many of them are blade tenderized to ensure tenderness. Therefore, this study was designed to look at objective tenderness measurements and consumer ratings of top sirloin steaks aged for three different times and cooked using four different treatments.
The objectives of this research were to compare consumer acceptance ratings and objective tenderness measurements of top sirloin steaks, aged for 14, 21, and 35 d, prepared with the following treatments: 1) Non-blade tenderized, cooked via sous vide (internal temperature of 63 °C for 90 min), chilled, reheated (2) Non-blade tenderized, cooked via sous vide, (internal temperature of 58 °C for 150 min), chilled, reheated; (3) Blade tenderized, cooked on flat-top grill (internal temperature of 70 °C); (4) Non-blade tenderized, cooked on flat-top grill (internal temperature of 70 °C)
Individually packaged USDA Choice (USDA, 2017) top sirloin butts (n = 240), similar to the North American Meat Institute (North American Meat Institute, 2014) Institutional Meat Purchasing Specifications (IMPS) 184B, were purchased from a major beef supplier, shipped to a purveyor, and aged (14, 28, or 35 d). Subprimals were assigned to one of the following cooking treatments: (1) non-blade-tenderized subprimal, fully cooked to lethality temperature with a higher temperature, shorter cook time sous vide process, followed by chilling and warming on a flat-top grill, (2) non-blade-tenderized subprimal; fully cooked to lethality temperature with a lower temperature, longer cook time sous vide process, followed by chilling and warming on a flat-top grill, (3) blade tenderized subprimal, cooked to a lethality temperature on a flat-top grill, and (4) non-blade-tenderized subprimal, cooked to a lethality temperature on a flat-top grill, and steaks (n = 960) were processed according to the cooking treatment.
Steaks (n = 80/ aging time) assigned to the sous vide (treatments 1 and 2) were cooked at a commercial facility in an Armor Inox ThermixTM Sous Vide System After cooking, steaks were rapidly cooled and transported to the Rosenthal Meat Science and Technology Center (College Station, TX). Upon arrival, steaks were stored under refrigeration (2 to 4 °C) for no longer than 7 days until analyses were performed. All steaks were reheated/cooked on one of two Star International commercial flat-top grills. Previously cooked sous vide steaks from treatments 1 and 2 were heated to 21 °C, flipped, and removed from the grill when the final temperature reached 46 °C. Raw steaks from treatments 3 and 4 were flipped at an internal temperature of 35 °C and removed from the grill when the final internal temperature reached 70 °C. Cooked steaks intended for WBS force evaluation were chilled until subsequent analysis using a TMS-Pro Food Texture Analyzer. Steaks assigned to consumer sensory panels and visual consumer appraisals were held in an Alto-Shaam oven set at 60 °C for no more than 20 min before serving to consumer panelists or visual assessment.
Steaks cooked via sous vide, using a lower temperature, longer time combination are generally comparable to steaks that have been blade tenderized and cooked on a flat-top grill based on WBS force values, sensory attributes and visual appraisal of exterior and interior surfaces. Although significant differences were discovered, all cooking methods and aging times produced steaks with WBS force values that were well within what is considered the “very tender” tenderness category.
Overall, our results demonstrate that top sirloin steaks cooked via sous vide, utilizing a low temperature, long time combination, followed by chilling and reheating resulted in a tender steak that was acceptable to consumers. Therefore, if food safety concerns are an issue for blade tenderized top butts, this cooking method would provide an alternative approach to preparing top sirloin steaks. This could greatly impact the beef industry by allowing further processors to produce more consistent products, in terms of tenderness and other sensory attributes, on a larger scale destined for foodservice operations, which should result in more consistent eating experiences by the consumer.