Meat quality of kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus)

[摘要] ENGLISH ABSTRACT: Although kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus) are found in thesame geographical area, there is variation in their diets as kudu are predominantly browsers,feeding on tree and shrub leaves, while impala are known as mixed feeders as they grazeand browse. Therefore this poses the question whether the diet would influence their meatquality. The objective of this investigation was to evaluate the physical measurements andchemical composition of M. longissimus dorsi, M. biceps femoris, M. semimembranosus, M.semitendinosus and M. supraspinatus for kudu and impala, two southern African antelopespecies. The effects of age (adult and sub-adult) and gender (male and female) were alsodetermined. The sensory characteristics of the M. longissimus dorsi muscle for sub-adultkudu and impala were investigated. Correlations between the various physicalmeasurements and chemical composition of the meat were verified. Physical measurementsand chemical composition of the M. longissimus dorsi muscle were tested for correlations withthe sensory ratings of the meat.Dressing percentage of impala (59.88%) (n=28) was higher than that of kudu (57.60%) (n=35).The main effects (species, gender and age) showed no differences for drip loss and cookingloss. However, muscles differed in terms of cooking loss with impala M. semitendinosushaving the highest (38.28%) value and kudu M. longissimus dorsi having the lowest value(30.77%). For impala, the highest Warner–Bratzler shear (WBS) values were measured for M.semimembranosus (5.90 kg/1.27cmø), followed by M. biceps femoris, M. longissimus dorsi,and M. semitendinosus with the lowest WBS values measured for M. supraspinatus (3.61kg/1.27cmø). All impala muscles had lower L* values and appeared darker in colour thankudu muscles, except for M. supraspinatus. Adult animals also had lower L* values than thesub-adult group. Kudu had significantly higher a* and b* values (more red) than impala.Chroma values were higher for kudu, thus appearing brighter in colour. The respectivemuscles of kudu and impala investigated differed significantly in terms of physicalcharacteristics. However, gender and age did not have an effect on the physicalmeasurements.Moisture content was higher in kudu meat (76.46%) than in impala meat (75.28%). Musclesdiffered for both moisture and fat content. The highest fat was found in M. supraspinatusfollowed by M. biceps femoris, M. semitendinosus, M. semimembranosus and M. longissimusdorsi. Protein content did not differ between species (kudu: 21.66%; impala: 22.26%), gender(male: 21.98%; female: 21.95%) and age groups (adult: 21.74%; sub-adult: 22.18%). Kudu M.longissimus dorsi (1.62%) had lower fat content than impala M. longissimus dorsi (2.22%) andfemale animals had a higher fat content than male animals. Sub-adults (1.20 ± 0.02%) hadhigher ash content than adults (1.10 ± 0.03%). The M. supraspinatus had the lowest protein and also the highest fat content, with M. semimembranosus having the lowest fat content butthe highest value for protein.Myoglobin content did not differ between species, although females had higher (6.58 ± 0.20mg/g) myoglobin content than males (5.11 ± 0.25 mg/g). Glycolitic muscles had the lowestmyoglobin content with the highest values found in M. supraspinatus, an oxidative muscle.An interaction was noted between species and muscle for myoglobin content. Myoglobincontent in impala M. longissimus dorsi was higher than that in kudu M. longissimus dorsi;however for all other muscles the myoglobin content was lower in impala.Gender did not affect mineral content. Potassium levels were highest for kudu whilephosphorus was more prevalent in impala meat. Adult and sub-adult groups differed in termsof potassium, calcium and zinc content. Potassium and calcium content were higher for subadultanimals while zinc content was higher in adult animals.In impala meat, stearic acid (22.67%) was the major fatty acid, followed by palmitic acid(16.66%). In contrast, oleic acid (24.35%) was the most profuse fatty acid in kudu, followedby linoleic acid (22.95%). The SFA's as a percentage of the total fatty acids differed betweenimpala (51.12%) and kudu meat (34.87%). Kudu meat had a higher concentration of totalPUFA (38.88%) than impala (34.06%) meat. The PUFA: SFA ratio for kudu meat (1.22) wasmore favourable than that for impala meat (0.73). The ratio of n-6 PUFA's to n-3 PUFA's forkudu and impala were determined as 2.22 and 3.76 respectively. From the current findings itis evident that kudu and impala meat have advantageous fatty acid profiles and can be ahealthy substitute for other red meats.Kudu meat (72.62 ± 1.86 mg/100g) had higher cholesterol than impala meat (55.35 ± 1.84mg/100g). It is recommended that further studies be done in order to confirm the cholesterolcontent of kudu meat.Within species, no gender differences for any of the sensory characteristics tested were noted.The impala meat had a more intense game aroma than the kudu meat, while kudu meat wasfound to be more juicy than impala meat. It can therefore be concluded that the marketing ofgame meat should be species-specific as there are distinct flavour and aroma differencesbetween kudu and impala meat.

[发布机构] Stellenbosch University