BACKGROUND 

Currently, the beef industry is interested in further investigating and pursuing the option to separate the Rib and Chuck between the 4th and 5th Rib with the acceptance of United States Department of Agriculture (USDA) for labeling and marketing purposes, which would ultimately result in adding additional weight and value to the “Rib” primal without sacrificing the desirable eating characteristics associated with the current Rib primal. Reuter et al. (2002) stated that “Based on analyses of shear force and consideration of consumer purchase preference information, there seems to be no logical reason for separating the beef wholesale Rib from the beef wholesale Chuck between the 5th and 6th Ribs other than tradition.” Reuter et al. (2002) also suggested that separating the Rib and Chuck between the 4th and 5th Rib was a viable option as it would have minimal effect on beef consumer satisfaction.

This study was aimed at further investigating the impacts of separating the beef Rib between the 4th and 5th Rib versus the 5th and 6th Ribs on beef tenderness, connective tissue content, product composition (visible lean and fat), and product yield.

METHODOLOGY

Thirty carcasses with the same USDA quality grade were selected alternating sides and fabricated into either an 8‐Rib Rib separated from the Chuck between the 4th and 5th Rib or a traditional 7‐Rib Rib separated from the Chuck between the 5th and 6th Rib. As a result, all comparisons between 8‐Rib and 7‐Rib Ribs were made within animal.

Individual identification was maintained for each Rib, and traditional carcass data measurements were collected from each carcass that Ribs resulted from. Concurrent to the fabrication procedures, weights for each product were collected and comprehensive. Within 7 days of product collection, the Ribeye Rolls were taken to a steak portioning facility, and all were cut into equally portioned Ribeye Steaks. At the time of portioning, steak weights, steak thicknesses, steak number/ count, and trim weights were collected and recorded, and an image of each steak was obtained. All meaningful dimensional measurements including total portion area, maximum length, maximum width, individual muscle areas, individual muscle lengths, individual muscle widths, fat areas, tail lengths, total area of lean, and total area of fat were measured and recorded for each image. Following image capture, steaks were individually identified, packaged and individually frozen and stored for shear force evaluations.

Warner‐Bratzler Shear Force (WBSF) values were obtained for the primary muscles in every steak resulting from all 30, 8‐Rib Ribs. A mean WBSF value was obtained and averaged for each muscle individually. Thawed steaks were cooked to a peak internal temperature of 71°C. The internal temperature of steaks was monitored with a thermocouple during cooking, and steaks were removed from the oven in order to achieve the desired peak internal temperature. Each steak was allowed to equilibrate to room temperature and a maximum number of cores for each muscle were removed. Each core was sheared once, perpendicular to the muscle fibers.

Comparisons of least squares means was computed for all measurements by treatment (8‐Rib vs. 7‐Rib) and for individual steak by steak location. The interaction of treatment and steak location was tested for individual steak measurements.

FINDINGS

The new fabrication style increased the length of the Rib by two inches per side, which resulted in 2.8 more steaks per carcass, on average. Although longissimus dorsi WBSF was affected by steak location, there were no meaningful trends by steak location, and the values were not affected by fabrication style (Table 1). The data indicated that tenderness and eating quality was not affected by the 4th and 5th Rib alternative Rib/Chuck break.

IMPLICATIONS

Changing the fabrication style would not detrimentally impact the eating qualities of Ribeye Steaks but would add significant weight and value to the Rib. These data will facilitate the decision of the beef industry and USDA to make changes to the definition of the beef Rib and allow for a change in fabrication procedures.