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Abstract The effect of olive oil inclusion on the chemical and sensory characteristics in cabanossi made with ostrich and warthog meat was investigated. Ostrich meat from soybean oilcake (SBOC) and cottonseed oilcake dietary inclusion levels (CSOC), and olive oil were included at three levels (0%, 1% and 2%) resulting in six treatments. The fat content in the cabanossi increased with increasing levels of oil inclusion but were all <10%, which allows it to be classified as a low fat meat product. Total monounsaturated fatty acids in the cabanossi increased whilst total saturated fatty acids and total polyunsaturated fatty acids decreased as olive oil increased. The SBOC cabanossi had a lower fat and higher crude protein content. The inclusion of olive oil at 2% resulted in a cabanossi with increased tenderness, juiciness and cured red meat colour, all factors that appeal to the consumer, while the overall flavour descriptors were not adversely affected by the inclusion of olive oil. Highlights • Different levels of olive oil were used as fat source in making ostrich/warthog cabanossi. • MUFA in the cabanossi increased whilst SFA and PUFA decreased as olive oil increased. • Olive oil at 2% resulted in increased tenderness, juiciness and cured red meat colour. • Overall flavour descriptors were not adversely affected by the inclusion of olive oil. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the effect of replacing dietary soybean oilcake meal with increasing levels of cottonseed oilcake meal (CSOCM) on the growth performance and meat (Iliofibularis muscle) chemical composition of ostriches in order to decrease total feed costs. A total of 105 ostriches were divided into five feeding groups according to the CSOCM inclusion level in the whole diet: Control (0% CSOCM), 3%, 6%, 9% and 12% CSOCM (of the whole diet), and fed with experimental diets from 6 to 13months of age. As a result of feeding CSOCM, the final live weight and the average daily gain significantly increased in the 12% CSOCM group. The proximate composition, cholesterol content, mineral and fatty acid profile of the meat remained unaffected. Thus CSOCM may be used as an alternative protein source to the more expensive soybean oilcake meal in ostrich nutrition. [Copyright &y& Elsevier]

Abstract: A pairwise comparison of the meat quality between fresh and frozen/thawed Musculus iliofibularis was conducted. Thirty-two (16 left; 16 right) muscles were collected and allocated to two treatments: fresh and frozen/thawed. Frozen vacuum-packed samples were stored for 1month at –20°C before thawing. The fresh samples had higher pH (P <0.05), water binding capacity (P <0.05), CIE L* (P <0.0001), CIE a* (P <0.05) and Chroma values (P <0.05) than the frozen/thawed samples, indicating the fresh samples were bright red in appearance and had minimal exudate. The frozen/thawed samples lost 5.09±0.21% moisture during thawing and had a greater drip loss (P <0.0001) and shear force (P <0.001). No differences were obtained with regard to cooking loss, CIE b*, hue and TBARS. Protein oxidation (mM carbonyls/mg protein) was lower (P <0.05) in the frozen/thawed samples, which was attributed to the higher (P <0.0001) protein concentration negating the higher (P <0.001) carbonyl content. Industrial freezing and thawing regimes negatively affected the quality of ostrich meat. [Copyright &y& Elsevier]

Abstract: This study was conducted to establish the shelf-life of ostrich steaks stored in four different packaging types: (i) air exposure, (ii) vacuum, and two different modified atmospheres packages (iii) MAP: 80% CO2 +20% N2, and (iv) MAP+CO: 30% CO2 +69.8% argon+0.2% CO. Shelf-life evaluation was based on colour, lipid and hemopigments oxidation, microbial counts and sensory assessment of odour and colour. Samples stored under air exposure showed the highest lipid and hemopigments oxidation rate. Based on aerobic bacteria counts, the shelf life of ostrich steaks stored under aerobic conditions would be 8 d at most, whereas under vacuum, MAP or MAP+CO it would be 12 d. The presence of CO extends the shelf life of ostrich steaks by stabilisation of red colour measured by instrumental and sensory techniques, and maintenance of fresh meat odour by slowing down off-odour perception. [Copyright &y& Elsevier]

Abstract: The matrix metalloproteinases (MMPs) are a homologous family of zinc proteinases that are collectively capable of catabolising the various macromolecular components of the extracellular matrix including collagens. In this study an MMP was successfully isolated and purified from ostrich skeletal muscle using Toyopearl Super Q-650S, hydroxylapatite and zinc-chelate chromatographies. The purified molecule had a molecular weight of 55K and a total of 467 amino acid residues. Purified ostrich MMP showed a pH optimum of 7 and a temperature optimum of 45°C. The activity of purified ostrich MMP was shown to be inhibited by metal chelators (1,10 phenanthroline and EDTA) and partially inhibited by soy bean trypsin inhibitor. All the functional properties of ostrich MMP were compared to previously reported values for MMPs from other sources. The MMP activities in ostrich meat during a 21-day ageing period were determined and an overall increase in MMP activities was observed. [Copyright &y& Elsevier]

Abstract: Cold-shortening is the response when muscles are exposed to temperatures below 10°C with a pH>6.20. The course of pH within hot-deboned and intact ostrich M. gastrocnemius, pars interna and M. iliofibularis were followed for the first 23–24h post-mortem to investigate the changes in pH as well as to determine the point of minimum pH for ostrich muscles post-mortem. The hot-deboned muscles took longer to reach the point of minimum pH than the intact muscles. There was no significant (P =0.4508) difference in the minimum pH (5.91±0.26) between the hot-deboned and the intact muscles. It was concluded that both the M. gastrocnemius, pars interna and the M. iliofibularis reached a pH<6.20 early post-mortem with muscle temperatures above 10°C; and therefore showed no risk of cold-shortening if these muscles were to be hot-deboned 2–4h post-mortem. [Copyright &y& Elsevier]

Abstract: Fresh ground ostrich meat was packaged under high oxygen (O2), high nitrogen (N2), vacuum (VAC) and ambient air (AIR) atmospheres, stored at 4±1°C and displayed under 1700±100lux of fluorescent lighting for 9 days. The meat was evaluated for changes in typical shelf-life characteristics consisting of pH, color properties (CIE L ∗, a ∗, b ∗, and total color difference, ΔE), oxidative changes (thiobarbituric acid value and hexanal content) and bacterial counts (total viable cell, coliform, lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp.) Initial meat pH was 6.16 and declined slightly during storage. TBA values and hexanal content were highest in O2 and lowest (P ⩽0.05) in VAC and N2 atmospheres. Surface lightness (L ∗) and redness (a ∗) were highest in O2 packaging initially, decreasing (P ⩽0.05) by day 9. ΔE of the ground ostrich increased during storage in only O2 and AIR packaging. All packaging methods had generally similar effects on microbial outgrowth. Total aerobic bacteria attained >106 CFU/g meat between day 3 and day 6. Ground ostrich meat was below saleable quality in less than 6 days based on all of the meat attributes. For O2 packaging however, quality based on lipid oxidation and color properties indicated a shelf-life of less than 3 days. Oxidation is likely the limiting factor for shelf-life of ground ostrich meat. [Copyright &y& Elsevier]

Abstract: Cold-deboning is currently practiced in South African ostrich abattoirs. However, the advantages of hot-deboning include the reduction of costs and time, but there is always the risk of cold-shortening. The effects of hot-deboning of ostrich M. gastrocnemius, pars interna on meat sensory attributes were investigated. The data showed that the hot-deboned muscles’ pH48 (6.57±0.18) was significantly negatively correlated (r =−0.7813; P <0.038) to the mean Warner–Bratzler shear force values (71.28±18.62 N, 12.7mm−1 diameter) and positively correlated (r =0.789; P <0.035) to the mean scores for taste panel tenderness (66.39±15.45). After storage for 48h post-mortem, the hot-deboned muscles were found to be less juicy (P <0.004) and, according to both sensory tenderness scores and Warner–Bratzler shear force values, tougher (P <0.0001) than the cold-deboned muscles. [Copyright &y& Elsevier]

Abstract: The effect of different levels of unrefined fish oil in the diet on ostrich Musculus iliofibularis was evaluated in a completely randomised experimental design, where a supplementary energy rich feed, containing 6.7% fish oil, was fed at four different levels over a 7-month period. An increase in the amount of fish oil consumed was found to have had no significant effect on the sensory characteristics of ostrich meat, although there was a tendency towards an increase in fishiness, for both aroma and flavour. Increased concentrations of fish oil, however, did have a significant effect on the aroma and flavour of the abdominal fat pads. The muscle pHf and muscle lightness (L*) revealed a significant reduction, with increased energy intake. However, the increased energy intake had no effect on the chemical composition (moisture, protein, fat, and ash content) of the meat. The fatty acid profile of both adipose tissue and muscle was altered as a result of the consumption of fish oil. The SFA concentration increased, while the PUFA concentration decreased with increasing dietary levels. The MUFA concentration remained constant for all four groups. [Copyright &y& Elsevier]

Abstract: Commercially reared ostriches (n =84) were randomly allocated to one of two groups. The first group (stressed: n =38) was deprived of food for a period of 2.5 days prior to slaughter, to simulate the stress experienced by slaughter ostriches held in holding pens (lairage) at a commercial ostrich abattoir over a weekend. The second group (control: n =46) was fed normally until 24 h prior to slaughter. Initial live weight as well as hot and cold drumstick weight were independent (P >0.05) of treatment. Stressed birds lost on average (±SE) approximately three times more weight than control birds over the experimental period (−3.2±0.6 vs. −1.0±0.5 kg, respectively). Full stomach and alimentary tract weights did not differ between treatments although there was a tendency for that derived from stressed birds to have lower stomach contents. The intra-muscular (Muscularis iliofibularis) pHf of stressed birds was 0.22 units higher (P &#60;0.01) than that of contemporaries in the control group 1 h post-slaughter (6.03±0.06 vs. 5.81±0.05, respectively). After 26.5 h in a refrigerated room, this difference still remained at 0.25 units (6.46±0.07 vs. 6.21±0.07, respectively; P &#60;0.05). Post-slaughter changes in intra-muscular pH followed approximately the same trend in stressed and control birds. Intra-muscular temperature was largely independent of treatment, although there was a suggestion of a slightly higher (P =0.18) temperature in stressed birds immediately post-slaughter. Cooking loss, drip loss and shearing values were not affected (P >0.05) by the withholding of food for 2.5 days. It can thus be concluded that withholding feed from ostriches on lairage over a period of 2.5 days does not have any negative influence on the meat yield or physical quality traits thereof. [Copyright &y& Elsevier]

The purpose of this trial was to study the effects of citrus pulp inclusion in ostrich diets on meat quality, evaluated on iliofibularis and gastrocnemius muscles. M. iliofibularis had a lower ultimate pH (P<0.05) and was lighter in colour (P<0.05) than M. gastrocnemius. The latter had higher moisture (P<0.05) and lower crude protein contents (P<0.05) as compared to M. iliofibularis. M. gastrocnemius had a lower proportion of C14:0 (P<0.05), C16:0 (P<0.05) and C16:1 (P<0.05) and a higher percentage of C18:0 (P<0.05), C20:2ω6 (P<0.05), C20:4ω6 (P<0.05) and C20:5ω3 (P<0.05) than M. iliofibularis. Citrus pulp diet increased (P<0.05) meat ultimate pH and reduced cooking losses (P<0.05) as compared to the control diet. Meat from animals given citrus pulp had lower crude fat (P<0.05) and ash percentages (P<0.05) in comparison to that from the control group. The proportions of intramuscular saturated and monounsaturated fatty acids were lower (P<0.05) in the citrus pulp group as compared to the control one. Meat from the citrus pulp treatment group had a higher (P<0.05) percentage of polyunsaturated fatty acids than meat from the control treatment. In particular, meat from ostriches given citrus pulp diet exhibited higher C18:2ω6 (P<0.05) and C20:4ω6 (P<0.05) contents that accounted for a higher ω6/ω3 ratio (P<0.05) as compared to the control group. Overall, the use of a citrus pulp-included diet in ostrich feeding did not adversely affect meat quality and, therefore, citrus pulp seems to be a possible ingredient to reduce feeding costs. [Copyright &y& Elsevier]

A trained taste panel could not distinguish (P>0.05) between ostrich meat patties containing either 10% pork lard or 10% of a modified starch/protein isolate (fat replacer) mixture. The panel could distinguish between the types of ostrich muscle/meat cuts used with a significant (P<0.05) number preferring ostrich patties made from meat containing a higher collagen content (±3% vs <1%). The chemical analysis of the patties showed that within the meat classes (Class fillet—de-membraned, Class A—very lean off-cuts and Class B—off-cuts containing visual connective tissue and some fat), the patties containing the pork fat had a +6% higher total fat content than those containing the fat replacer. The fatty acid profiles of the various products were in accordance with the meat type and fat or fat replacer used. The mineral profile was as expected for lean ostrich meat that had spices added. It is concluded that fat replacers can be used successfully for the production of low fat ostrich patties without any negative quality attributes being perceived. [Copyright &y& Elsevier]

Literature has identified a number of stressors that have negative impacts on the welfare of ostriches during transportation. In order to maintain or improve the welfare of animals it is important to minimise or eliminate the impact of such stressors. Literature suggested that ostrich welfare during transit might be improved by using darkened vehicles. A preliminary study was carried out which measured the response of ostrich heart rate and skin temperature (indicators of stress) to transportation. Comparisons were made between transportation during the day and at night. Statistical tests suggested that heart rates and skin temperatures recorded during the night were lower than those recorded during the day. The usual response of ostriches to darkness is to sit, which provides greater stability for the bird while the transportation unit is in motion. Temperatures inside the transportation unit were significantly lower at night. This may also contribute to the lowering of heart rate and skin temperature as it reduces effects of heat stress. The conclusion has been drawn that transporting ostriches at night is potentially beneficial for the reduction of stress and maintenance of welfare. [Copyright &y& Elsevier]

Ten Blue Neck ostriches were used to study the effect of age at slaughter (10–11 and 14–15 months) and muscle on fatty acid profile, cholesterol content and texture of meat. Fatty acid profile of ostrich meat was significantly affected by age at slaughter (P<0.001) and muscles (P<0.001). Different age at slaughter (10–11 vs. 14–15 months) produced an increase of P/S ratio (P<0.001), total saturated (P<0.05) and monounsaturated (P<0.001) fatty acids. The highest percentage of saturated and monounsaturated fatty acids were found in M. iliofibularis (P<0.001), whereas M. gastrocnemius showed the highest content of polyunsaturated fatty acids (P<0.001). Analysis of variance of data on cholesterol content (mg/100 g of meat) showed no significant effects of age at slaughter and muscle location. No effect of age on shear values was observed, whereas sensory panellists scored meat from younger birds as more tender (P<0.001). Both instrumental and sensory evaluation indicated that meat from M. iliofibularis was more tender (P<0.001). [Copyright &y& Elsevier]