HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Calkins, C. R. Articles by Seideman, S. C. Search for Related Content PubMed Articles by Calkins, C. R. Articles by Seideman, S. C.

Relationships among Calcium-Dependent Protease, Cathepsins B and H, Meat Tenderness and the Response of Muscle to Aging^1,2,

University of Nebraska, Lincoln 68583-0908

Abstract

This study was conducted to compare the relative importance of Ca-dependent protease (CDP) and cathepsins B and H to meat tenderness and changes in tenderness in response to postmortem cooler aging. Charolais bulls (n = 8) and steers (n = 7) were slaughtered at 15 mo of age and total activities of CDP-I (a protease with neutral pH optimum that requires micromolar amounts of Ca for activity) and cathepsins B and H (lysosomal proteases with acidic pH optima) were determined within 1 h. Shear-force values were obtained after 1, 3, 6, 9 and 14 d of aging. Data were pooled when analysis of variance revealed no differences between bulls and steers. Initial shear force was correlated (r = –.71, P < .10, n = 7) to CDP-I activity (only seven animals sampled for CDP-I), and the overall change in shear force (d 1 to d 14) was correlated to cathepsin B (r = .59, P < .05, n = 15). Most of the aging response occurred between d 3 and d 6 (41.6%), and changes in shear force during this period were related to total activities of cathepsins B and H (r = .44, .64, respectively, P < .05). Collectively, cathepsins B and H accounted for 35 and 58% of the variation in shear force change between d 1 to d 14 and d 3 to d 6, respectively. These data suggest that CDP-I helps to establish initial (d 1) meat tenderness but that cathepsins B and H are responsible for the tenderization that occurs during aging. By manipulating live animal growth and postmortem handling, it might be possible to control meat tenderness through the actions of these enzyme systems.

¹ Journal Series No. 8392, Agric. Res. Div., Univ. of Nebraska.

² The authors wish to acknowledge M. Koohmaraie of the Roman L. Hruska U.S. Meat Anim. Res. Center, Clay Center, NE for providing the CDP enzyme data.

³ Dept. of Anim. Sci.

⁴ Currently with Bryan Foods, West Point, MS 39773.

This article has been cited by other articles:

				G. Q. Zhang, Q. G. Ma, and C. Ji Effects of Dietary Inosinic Acid on Carcass Characteristics, Meat Quality, and Deposition of Inosinic Acid in Broilers Poult. Sci., July 1, 2008; 87(7): 1364 - 1369. [Abstract] [Full Text] [PDF]

				S. L. Gruber, J. D. Tatum, J. A. Scanga, P. L. Chapman, G. C. Smith, and K. E. Belk Effects of postmortem aging and USDA quality grade on Warner-Bratzler shear force values of seventeen individual beef muscles J Anim Sci, December 1, 2006; 84(12): 3387 - 3396. [Abstract] [Full Text] [PDF]

				D. L. Meyer, M. S. Kerley, E. L. Walker, D. H. Keisler, V. L. Pierce, T. B. Schmidt, C. A. Stahl, M. L. Linville, and E. P. Berg Growth rate, body composition, and meat tenderness in early vs. traditionally weaned beef calves J Anim Sci, December 1, 2005; 83(12): 2752 - 2761. [Abstract] [Full Text] [PDF]