Project Summary

Novel Approach to Aging Beef: Vacuum-packaged Foodservice Steaks Versus Vacuum-packaged Subprimals

Principle Investigator(s):
Jeff W. Savell
Texas A&M University
Completion Date:
May 2014



In an effort to meet consumer expectations for high quality beef products and exceptional eating experiences, aging of fresh beef for retail or foodservice has become a necessity. To date, no research is available to draw quality attribute comparisons between steaks derived from wet-aged subprimals versus steaks wet-aged as a cut product.

Cutting steaks from subprimals before the aging process may allow the industry to realize economic advantages without negatively impacting beef quality. By cutting steaks prior to aging, throughput of trimmings for various applications would become both faster and more efficient. Furthermore, storage of large boxed subprimals would be largely reduced, lessening the burden on cooler storage capacity. Processors would still have to accommodate storage of the vacuum-packaged steaks during aging, but the smaller product units should allow commercial processors added storage flexibility with smaller packages, fewer boxes and would ultimately contribute to improving several factors involved in sustainability of beef processing.

The objective of this study was to determine differences in quality attributes of steaks derived from aged subprimals versus those aged as steaks.


Paired subprimals (Ribeye, Strip Loin, Top Sirloin Butt, Shortloin and Tenderloin) were selected from a commercial beef harvest and processing facility. Upon arrival at a commercial further processing facility, each subprimal within a pair was assigned randomly to one of two treatment groups: (1) aging of vacuum-packaged subprimals (Ribeye, Strip Loin, Top Sirloin Butt, Tenderloin and Shortloin) or (2) aging of vacuum-packaged steaks (boneless Ribeye, boneless Strip, boneless Top Sirloin, boneless Tenderloin and Porterhouse or T-bone). Those subprimals destined for aging as steaks were swabbed for baseline microbiological analyses (lactic acid bacteria and aerobic plate count), weighed for purge evaluation, cut into steaks 7 days postmortem and vacuum-packaged. At the conclusion of each assigned aging period, aged subprimals were cut into steaks and vacuum-packaged (Figure 1). To simulate typical handling and distribution, steaks then were held an additional 14-days under refrigerated conditions (approximately 4 °C). At the end of the 14 day storage period, steaks were assigned randomly to one of three assay groups: color/tenderness, microbiological shelf-life (Figure 2) or consumer sensory.


Aerobic plate counts and lactic acid bacteria counts for the ribeye and strip loin were higher (P < 0.05) for aged subprimals when compared to aging as steaks. Generally, microbial counts were low for all treatment groups which may be attributable to a successful multiple-hurdle intervention system. There was a greater amount of purge seen in subprimal-aged product compared to steak-aged product across cuts (P < 0.05). Bone-in cuts from steak-aged groups did result in a higher frequency of off-odors when compared to subprimal-aged products. However, cutting subprimals into steaks before aging did not negatively impact consumer perception of beef palatability for Ribeye, T-bone/Porterhouse, Tenderloin or Top Sirloin Steaks (P < 0.05). Table 1 shows that aging as Strip Steaks rather than as a Strip Loin Subprimal positively impacted consumer ratings for overall liking, flavor liking, juciness liking and tenderness liking (P < 0.05). There were no significant differences in Warner-Bratzler tenderness measurements comparing steak-aged versus subprimal-aged product for Ribeye, Strip Loin, T-bone/Porterhouse and Tenderloin steaks. There was a small numerical, but significant, increase in Warner-Bratzler shear force measurements for Top Sirloin Steaks that were steak-aged versus subprimal-aged. Steak aging is likely a method that can be used to achieve aging benefits in fresh beef cuts while minimizing storage needs.


Overall, findings from this study support the practice of portioning subprimals into steaks before aging.


Table 1. Least squares means of consumer panelist scoresa for beef palatability attributes stratified by subprimal type and aging treatmentb.

Overall Liking Flavor Liking Juciness Liking Tenderness Liking Tenderness Level
Subprimals Steak Sub Steak Sub Steak Sub Steak Sub Steak Sub
Ribeye c 6.72 6.35 6.93 6.36 6.43 5.75 6.81 6.54 6.79 6.44
Strip Loin c 6.71a 5.90b 6.69a 5.87b 6.38a 5.18b 6.93a 6.06b 6.89 6.28
T-bone/porterhouse c 5.95 6.4 6.23 6.8 5.62 6.03 5.71 5.97 5.56 5.92
Tenderloin d 7.96 8.01 7.61 7.54 8.29 8.15 8.46 8.55 8.47 8.58
Top sirloin butt e 6.08 6.26 6.13 6.44 6 5.69 6.35 6.43 6.1 6.34

  • Means within a subprimal type and consumer sensory panel attribute lacking a common letter (a, b) differ (P < 0.05).
  • a Consumers used the following scale: overall liking (1=dislike extremely; 10=like extremely), flavor liking (1=dislike extremely; 10=like extremely), tenderness liking (1=dislike extremely; 10=like extremely), level of tenderness (1=dislike extremely; 10=like extremely), juiciness liking (1=dislike extremely; 10=like extremely). 
  • b Subprimals were assigned randomly to one of two aging treatments: (1) intact subprimals were aged and portioned into steaks at the end of the aging period, or (2) subprimals were portioned into steaks prior to aging.
  • c Ribeyes, Strip Loins, and T-bone/Porterhouses were aged for 42 days prior to consumer evaluation.
  • d Tenderloins were aged for 35 days prior to consumer evaluation.
  • e Top sirloin butts were aged for 49 days prior to consumer evaluation.