This exploratory study determined the ideal ageing period for optimum tenderness of Longissimus thoracis et lumborum (LTL), Semimembranosus (SM) and Biceps femoris (BF) steaks from male and female giraffe. The muscles of eight male and seven female giraffes were divided into 10 steaks each, and each steak was randomly allocated to age for 1, 5, 9, 14, 18, 22, 26, 30, 34 or 38 days in vacuum-sealed bags at ±4 °C. At each time point, the pH, surface colour, purge loss, cooking loss and Warner–Bratzler shear force (WBSF) were determined for the respective steaks. Significant interactions between the sex, muscle and days post mortem were observed for the Warner–Bratzler shear force (WBSF), CIE a*, CIE b*, hue-angle, and chroma, while the CIE L* values were affected by an interaction between muscle type and days post mortem. The pH showed three distinct phases: over Days 1–9, the pH (~5.54–5.55) was stable; over Days 14–22, it declined; and the pH dropped more sharply between Days 22 and 26 (~5.42 to ~5.32), before plateauing. The purge loss initially increased rapidly, after which the rate decreased during the ageing period; however, the cooking loss, which was affected only by muscle, remained constant throughout. The tenderness improved until Day 22 across all three muscle types (19.1 ± 0.30 N), after which it plateaued. The colour improved, in terms of redness and saturation, until Day 18 (L* = 44.1 ± 0.29; a* = 15.7 ± 0.19; b* = 15.3 ± 0.08; hue-angle = 44.8 ± 0.39; chroma = 22.0 ± 0.15); thereafter, discolouration occurred. Vacuum-ageing giraffe meat for 14–22 days is recommended to improve tenderness and colour and minimise the negative effects of increased purge loss. This recommendation is based on instrumental measurements with discolouration as a major determinant of acceptability. It is suggested that future research validate this through sensory evaluation and microbial analyses.
Silberbauer et al. (Sat,) studied this question.