Doctoral Dissertations

Date of Award


Degree Type


Degree Name

Doctor of Philosophy


Animal Science

Major Professor

J.T. Miles

Committee Members

William R. Backus, S.L. Hansard, R.R. Shrode, Archie Mathews


Measurements of tenderness were made on the semimembranosus muscle using the Armour Tenderometer (AT), Warner-Bratzler Shear (WB), Instron Universal Testing Instrument (Instron) and subjective evaluations.

Muscles used came from 35 beef animals, five from each of seven mating types: Charolais-Hereford (CH) dams bred to Hereford (H) or Charolais (C) bulls, H dams bred to Simmental (S), Maine-Anjou (MA), Limousin (L) or H bulls. Thus, the breed groups represented were: H X H, C X H, H X C H, C X CH, S X H, M A X H and L X H.

Penetration-force values were obtained from raw muscle with the AT. Cores one-half inch in diameter, from cooked muscle were used with the WB and the Instron. Maximum-shear-force values were obtained with the WB while maximum force (IMF) and "area under the curve" (lAR) values were obtained with the Instron. A 10-member taste panel (TP) evaluated each muscle for tenderness on a hedonic scale of 1 (extremely tough) to 10 (extremely tender).

A comparison of the seven breed groups was made within each method of evaluation. The following breed groups were ranked most tender by the various methods: TP, H X CH; WB, H X C H; IMF, H X C H; IAR, L X H and AT, H X H.

Analysis of variance showed no significant variation due to differences between the WB and IMF shear values, differences between breeds or interaction between instrument and breed. Highly significant product-moment (PM) correlations and rank correlations were found between: TP and WB, TP and IMF, TP and lAR. No indication was found of any relationship between the AT values and TP scores. The PM correlations and rank correlations between the WB values and the IMF values, between WB and lAR values and between IMF values and lAR values were highly significant. The correlations of AT values with other objective measures of tenderness were nonsignificant.

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