Meat studies of indigenous Southern African cattle. II. Textural evaluation of rib cut samples from carcasses of Afrikaner, Nguni and Pedi bulls fed intensively

Abstract

Textural evaluations were conducted on the longissimus thoracis muscles from carcasses of young Afrikaner, Nguni and Pedi bulls fed intensively and slaughtered at 160, 290, 340 and 390 kg. Carcasses were stimulated electrically (500 V, 12,5 Hz) for 2 min, and chilled for 19 h at 0-5 °C. Ribcut samples (II, 12 and 13th ribcut) were removed 24 h post-slaughter and evaluated by a taste panel for tenderness, juiciness, flavour and residue on an unstructured five-point scale, ranging from least to most acceptable. Shear tests were performed on an Instron apparatus. Percentage cooking loss and free water were measured. The Afrikaner was found to be slightly more tender and flavoursome with less residue than the Nguni (P < 0,10). The Pedi did not differ from the Afrikaner or the Nguni. No breed differences occurred in juiciness, cooking loss, free water or shear force. Mass affected juiciness (P < 0,05), residue (P < 0,01) and free water (P < 0,01). Shear force correlated highly with tenderness (-0,61**) and residue (0,74**). Juiciness correlated negatively with percentage cooking loss (-0,57'\ though poorly with percentage free water (0,28). Compared with published results of textural evaluation of steer meat, the meat from the young Afrikaner, Nguni and Pedi bulls fell into a superior category.
Die tekstuur van ribsnitrnonsters afkomstig van intensief-gevoerde, ongewisselde Afrikaner-, Nguni- en Pedi-bulle, geslag op teikenmassas van 160,290, 340 en 390 kg, is geevalueer. Karkasse is elektries gestimuleer (500 V, 12,5 Hz) vir 2 min, en verkoel teen 4°C vir 19 h. Ribsnitte (ribbes 11, 12, 13) is 24 h na slagting  verwyder. Monsters is voorberei en deur 'n proepaneel volgens 'n ongestruktureerde vyfpuntskaal vir sagtheid, sappigheid, smaaklikheid en residu geevalueer. Snyweerstandtoetse is met behulp van 'n Instron-apparaat bepaal. Persentasies kookverlies en ongebonde water is gemeet. Die Afrikaner se vleis was meer sappig en smaakvol (P < 0,10) as die Nguni. Die Pedi het nie van die Afrikaner of die Nguni verskil nie. Geen rasverskille het ten opsigte van sappigheid, kookverlies, ongebonde water of snyweerstand voorgekom nie. Massa het 'n invloed op  sappigheid (P < 0,05), residu (P < 0,01) en ongebonde water (P < 0,01) gehad. Snyweerstand was hoogs gekorreleer met sagtheid (-0,61**) en residu (0,74**). Sappigheid was negatief gekorreleer met persentasie kookverlies (-0,57**), maar nie betekenisvol met ongebonde water (0,28) nie. Die gehalte van die vleis van jong Afrikaner-, Nguni- en Pedi-bulle, in vergelyking met die van jong osse in  gepubliseerde resultate oor tekstuurevaluasie, is baie goed en sal vir die verbruiker aanvaarbaar wees.