The proteasome is renowned for its high molecular weight, multisubunit and mulicatalytic nature. One of its many suggested roles is the degradation of myofibrillar proteins, and therefore it has been proposed to play a role in the meat tenderisation process. The aim of this study was therefore to isolate, purify and characterise the 20S proteasome from ostrich skeletal muscle, with a view to ultimately investigating its role in the tenderisation process of ostrich meat. The 20S proteasome was successfully isolated and purified from ostrich skeletal muscle using Toyopearl Super Q-650S, Sephacryl S-300, hydroxylapatite and Mono Q chromatographies. The intact molecule showed a molecular weight of 725 K and a pI of 6.67. The subunits showed a molecular weight range of 22.2-33.5 K and a pI range of 3-9. 2D-PAGE revealed at least 14 polypeptides. The amino acid composition of the intact enzyme and of each of the eight subunits separating on SDSPAGE, as well as the N-terminal sequences of five of the eight subunits, were determined. The trypsinlike (Tr-L), chymotrypsin-like (ChT-L), peptidylglutamyl peptide hydrolase (PGPH) and caseinolytic activities showed pH optima of 11, 9, 7-8 and 10.3, and temperature optima of 40, 60, 70 and 60oC, respectively. The pH stability range for all four activities was 5-12. The ChT-L and PGPH activities showed thermostabilities up to 60oC, whereas the Tr-L and caseinolytic activities were stable up to 40o C. The enzyme showed complex kinetics. It was inhibited by the peptide aldehyde Z-LLL-CHO and cysteine protease inhibitors. Cations had negligible effects on the enzyme, excepting for Ca2+ and Mg2+. Of the detergents tested, SDS had the most potent stimulatory effect, particularly on the PGPH and caseinolytic activities. The fatty acid studies showed that unsaturation enhanced the ChT-L and the caseinolytic activities, while it completely suppressed the Tr-L activity. Heating at 60oC for 1-2 min stimulated the caseinolytic and PGPH activities. The studies on the role of ostrich skeletal muscle 20S proteasome in ostrich meat tenderisation suggested a definite but minor role of this enzyme, based on the fact that it remained active throughout the 12 days of storage of ostrich M. iliofibularis meat at 4oC and that it participated in myofibril degradation of post-mortem muscle, but to a small degree. These results support the proposal that the proteasome comes into play after the calpains have initiated degradation. However, there was a lack of improvement in tenderness values and minimal myofibrillar degradation over the 12-day storage period of the ostrich M. iliofibularis meat, leading to the conclusion that the tenderisation of this meat was incomplete after 12 days.

Cathepsin D, a muscle proteinase, participates in lysosomally mediated protein degradation in vivo. This enzyme has been proposed to play a significant role in the postmortem proteolysis process apparently associated with tenderisation. The lack of data on the postmortem characteristics of ostrich meat, especially on the ageing process and its influence on meat tenderness, called for an investigation into this process. There is no data available for purified ostrich cathepsin D, and the aim of this study was, therefore, to isolate, purify and characterise cathepsin D from ostrich skeletal muscle and subsequently investigate the possible role that it may have in the tenderisation process of meat. Cathepsin D was successfully isolated and purified from ostrich skeletal muscle using pepstatin A-agarose chromatography. The purified enzyme was composed of two subunits (14 and 29kDa). The amino acid composition as well as the N-terminal amino acid sequence of both subunits were determined. Kinetic parameters (Km and Vm), thermodynamic parameters (Ea, ∆H, ∆S and ∆G) and functional characteristics (effect of pH, temperature and various inhibitors on cathepsin D activity) were determined and are reported in this study. Ostrich muscle cathepsin D showed a pH optimum of 4 and a temperature optimum of 45°C. The activity of cathepsin D was strongly inhibited by pepstatin A and DTT. Purified ostrich cathepsin D displayed kinetic and functional properties similar to previously reported values from various species. The effect of storage on the activity of cathepsin D was investigated over a 30 day period. It was established that substantial postmortem cathepsin D activity remained throughout the storage period, to implicate cathepsin D, fulfilling a possible role in meat maturation.

The ostrich is becoming an important source of meat for humans in developed and developing countries. This study was conducted to purify and characterize myofibrilbound serine protease (MBSP) and its endogenous inhibitor (MBSPI) from skeletal muscle of the ostrich. It is well documented that MBSP is tightly bound to myofibrils and its endogenous inhibitor has been purified from the same tissue of other studied mammalian species. Literature supports an association of MBSP and its endogenous inhibitor with the degradation of myofribrillar proteins, resulting in the softening of muscle that lead to the conversion of muscle into meat with the control of the inhibitor. MBSP was successfully dissociated from washed myofibrils by 40 percent ethylene glycol at pH 8.5. Following centrifugation, MBSP was partially purified in two chromatographic steps, namely Toyopearl Super Q 650S and p-aminobenzamidine-Agarose. On the other hand, MBSPI was fractionated from the sarcoplasmic fraction using 75 percent ammonium sulfate saturation, followed by centrifugation and partially purified by three chromatographic steps, namely Toyopearl Super Q 650S, Superdex 200 and HiTrap SP HR. Ostrich MBSP was physicochemically and kinetically characterized, while MBSPI was only physicochemically characterized. Ostrich MBSP revealed an Mr of 21 kDa, cleaving synthetic fluorogenic substrates specifically at the carboxyl side of arginine residues. Optimum pH and temperature of ostrich MBSP were 8.0 and 40˚C, respectively. Kinetic parameters (Km and Vmax values) were calculated from Lineweaver-Burk plots. The characteristics of ostrich MBSP were compared to the values obtained for commercial bovine trypsin in this study, as well as that obtained for MBSP from various fish species and mouse. The results suggest that ostrich MBSP is a trypsin-like serine protease, thereby confirming the existence of MBSP in ostrich skeletal muscle. Partially purified ostrich MBSPI (Mr 17 kDa) (one form) shares 100 percent identity to myoglobin from the same species, while 2 other forms of MBSPI (Mr values of 35 and 36 kDa) exhibited high sequence identity to glyceraldehyde 3- phosphate dehydrogenase (GAPDH) (76 percent) from human and rat.

Thesis (PhD)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Although small, the South African ostrich industry contributes 60% to the total world production of slaughter ostriches. Ostrich leather contributes more than 50% of the R2.1 billion turnover of this industry. This study is the first structured investigation into the characteristics of ostrich leather focussing on factors such as age, nutrition, slaughter weight, and genetics, and the influence thereof on intrinsic leather traits. Large variation in terms of skin quality was found between producers, month of the year and production years. The effect of age suggested that leather thickness and tensile strength increased with age while the number of nodules declined by 2.8 for every month increase in slaughter age. Slit tear strength and tensile strength increased with heavier slaughter weights. Older ostriches had higher values for slit tear strength and skin thickness. Nodule diameter increased at a rate of 0.08mm per month increase in age. Nodules with an average diameter of more than 4.0mm were only obtained in the combination of old heavy birds, while nodule diameter of the other age-weight combinations ranged between 3.3mm and 3.5mm. Subjective assessment of nodule traits by participants with or without prior knowledge of age suggested that slaughter age accounted for 46% of the variation in estimated slaughter age. Nodule acceptability scores generally increased with an increase in slaughter age. Moderately acceptable scores were found in skins from birds 11 months and older. The effect of energy and protein concentrations of ostrich diets suggested that raw skin areas were 19.4% and 21.8% larger at slaughter for birds receiving a diet containing 10.5 MJ/ME and 12.0 MJ ME/kg DM respectively, compared to that of birds receiving a 9.0 MJ ME/kg DM diet. Leather thickness taken parallel to the spine was increased by 13% when birds were fed the higher energy diet. Dietary protein concentrations failed to influence skin weight, skin area or any physical leather properties. The genetic variation in nodule size measured at different sampling sites on the skin suggested that nodule size increased chronologically with age at the neck, back, upper leg, and flank and butt areas. Estimates of h² for nodule size ranged from 0.09 ± 0.07 on the flank region to 0.24 ± 0.10 on the upper leg region. Preliminary results seem to suggest that nodule size on different locations of the skin is not necessarily the same genetic trait. It was concluded that measurements at any specific site is unlikely to predict measurements at other sites with a high degree of accuracy due to the large variation that exists between measurement sites. This dissertation provides an insight into the complexity of ostrich leather quality, and the interaction of leather traits, such as nodule size and shape, leather thickness and tensile strength, that determine ostrich leather quality. / AFRIKAANSE OPSOMMING: Alhoewel klein, produseer die Suid-Afrikaanse volstruisbedryf 60% van die totale wêreldproduksie van slagvolstruise. Volstruisleer is verantwoordelik vir meer as 50% van die R 2.1 biljoen omset van die bedryf. Hierdie studie is die eerste gestruktureerde ondersoek na die intrinsieke eienskappe van volstruisleer en die invloed van ouderdom, voeding, slagmassa en genetika op hierdie eienskappe. Groot variasie t.o.v. leerkwaliteit is waargeneem tussen produsente, maande van die jaar en produksiejare. Die effek van ouderdom toon dat leerdikte en treksterkte verhoog het met toename in ouderdom, terwyl die aantal knoppies afneem met 2.8 vir elke maand toename in slagouderdom. Skeur- en treksterkte het verhoog met ʼn swaarder slagmassa (64kg vs. 99kg). Hoër waardes vir skeursterkte en veldikte is vir ouer voëls (384 dae vs. 234 dae ouderdom) verkry. Knoppie deursnit het teen ʼn tempo van 0.08mm per maand toename in ouderdom verhoog. Knoppies met ʼn gemiddelde deursit van groter as 4.0mm is slegs waargeneem in swaar-ou voëls, terwyl die knoppie deursnit van die ander massa-ouderdom kombinasies tussen 3.3mm en 3.5mm gewissel het. Die subjektiewe waarneming van 28 respondente, ingelig of oningelig oor die betrokke slagouderdom, dui daarop dat die werklike slagouderdom verantwoordelik is vir 46% van die variasie in geskatte slagouderdom. Die puntetoekenning vir knoppie-aanvaarbaarheid het verhoog met ‘n toename in slagouderdom. Aanvaarbare puntetoekenning vir knoppie-ontwikkeling is verkry vir voëls vanaf 11 maande en ouer. Die effek van energie- en proteïenkonsentrasies in volstruisdiëte toon dat die rouveloppervlakte onderskeidelik 19.4% en 21.8 % groter was met slagting vir voëls wat onderskeidelik ‘n 10.5 MJ/ME en 12.0 MJ ME/kg DM diëte gevoer is, in vergelyking met voëls wat ‘n 9.0 MJ ME/kg DM dieet ontvang het. Leerdikte, geneem parallel met die ruggraat, het met 13% toegeneem wanneer die hoër energie dieet gevoer is. Dieetproteïen konsentrasies het geen invloed op velmassa, veloppervlakte of enige fisiese leerkwaliteitseienskappe gehad nie. Die genetiese variasie in knoppiegrootte geneem op verskillende lokaliteite op die vel toon ʼn chronologiese toename met ouderdom in die nek-, rug-, boud-, sy- en stuitjie gebiede. Beraamde h² vir knoppiegrootte wissel vanaf 0.09±0.07 op die sye tot 0.24±0.10 op die boudgedeelte. Voorlopige resultate dui aan dat knoppiegrootte op verskillende lokaliteite nie noodwendig dieselfde genetiese basis het nie. Die gebruik van een lokaliteit vir die voorspelling van die eienskappe van ʼn ander, blyk nie sinvol te wees nie a.g.v. die groot variasie wat tussen verskillende lokaliteite bestaan. Hierdie studie verskaf insig oor die kompleksiteit van volstruisleerkwaliteit en die interaksie van leereienskappe soos knoppiegrootte en –deursnit, veldikte en treksterkte, in die bepaling van leerkwaliteit.

The research program addressed in this study was to do an analysis of the potentials of the marketing of ostrich meat in the South African market. Being the world leader in the ostrich industry, the research’s emphasis was to establish reasons why the meat industry does not explore the South African meat market. To achieve this object, a literature study to determine the key components of the current situation was undertaken and used as a theoretical model to analyse the current situation in the market as well as in the ostrich industry. In addition to the literature study, an empirical study was conducted to identify some critical issues that have an influence on the potential of the domestic market. The survey method used, based on the key components gained from the literature study, consisted of an in-depth scan of the macro-environment and thorough investigation of the target industry. The investigation involved using the Internet and World Wide Web, print media, personal interviews and telephonic interviews. The result of the literature study was finally combined with the results of the empirical study and some recommendations were made. The recommendations were applicable to the ostrich industry in so far that implementing some plans for the meat industry can have serious consequences for the other products of the ostrich industry

The changing agricultural environment (dualistic agricultural landscape, land reform programme, market liberalisation and globalisation) has caused emerging ostrich farmers to become increasingly isolated. Governmental agriculture reforms and public sector interventions have been insufficient to address all the challenges faced by rural ostrich farmers in the Eastern Cape. Participation in the ostrich supply chain for emerging farmers in the Eastern Cape is currently unsustainable as a result of avian influenza, control and registration protocols for ostriches (VPN04), structural barriers in marketing, technical constraints and a lack of market participation. People in the rural areas of the Eastern Cape are challenged by inferior infrastructure, poor site conditions, low earnings, poor access to health services and unreliable water sources. The marginal conditions and prevalent complexities in which agriculture is practised require costly resource intervention. Intensive ostrich production necessitates continuous genetic improvement, methodical record keeping, intensive egg incubation methods and highmaintenance chick rearing and ostrich handling while minimising feed costs throughout this process. Rural farmers have not embraced ostrich farming in the same way as they have done with other livestock farming because it does not offer the anthropological functions that traditional livestock farming provides. The ostrich supply chain requires a wide range of activities to bring products to the final consumer. The worth of ostrich production lies mainly in the higher returns which are achieved only through the export markets. Today the ostrich industry has become vulnerable to market cannibalism, a lack of market development, unregulated numbers of ostriches and recurring international meat bans. The deregulation of the ostrich single-channel marketing system had a substantial effect on the value chain on which farmers depended for market access and market protection. As the majority of ostrich products are being exported to the European Union, the role of intermediary agencies is becoming an important factor influencing entry into the high-end markets. This agent structure that represents the South African ostrich industry is vital for the distribution, market penetration and regulation of the ostrich products. The ostrich leather, which is today the main product line, is primarily used for luxury goods and is susceptible to economic downturn and over-supply. The ostrich meat industry has been severely influenced by outbreaks of avian influenza and processors now pre-heat the meat in order to maintain export. However, this preheating meat facility is only for export produce and available to farmers who conform to VPN04 and have officially registered farms. The relevant South African government departments played a crucial role in identifying avian influenza outbreaks and liaising with the European Union about avian influenza isolation strategies. No previous studies have been conducted on the participation of emerging farmers in the Eastern Cape ostrich-industry supply chain and on the interventions required to address the multiple constraints and forces in this sector. This led to a study with research emphasis on the required capacity for supply-chain participation and the supporting mechanisms that would be required for emerging ostrich farmers to integrate successfully into this supply chain. An exploratory research approach was chosen for the investigation, as no earlier research has been undertaken that could serve as a source of reliable data or reference. A triangulation research methodology using both the quantitative and the qualitative approach was applied. The qualitative research entailed an interpretive approach associated with using grounded theory and content analysis for interpreting data. The comparative case study design was the main qualitative research instrument for the multiple-case studies on emerging ostrich farmers in the Eastern Cape. The study was undertaken at five different sites, namely, the Peddie Ostrich Programme, the Rockhurst Ostrich Programme, the Hlumani Co-operative farm, the Zamukwanda Ostrich farm near Pearston and the Mimosadale Ostrich farm. The quantitative methods were applied to capture all the measurable components and representations of the stakeholders and participants, through interviews, questionnaires and focus group interviews. The quantitative study also included an experimental instrument to measure the capacity of emerging farmer programmes for supply chain participation. It was found that the main driver for three of the case studies pertained to land ownership and that ostrich farming was incidental and only seen as means of activity for income. These three humanitarian farming projects had limited capacity for intensive management requirements for ostrich farming. It was found that the VPN04 bio-security protocols and disease control require a higher level of record keeping for EU markets and is prohibitively expensive for poor rural emerging farmers. The study established that the emerging ostrich farming programmes contributed value to the industry and government rural development in land redistribution programmes, vehicles for reduction of poverty and job creation in the rural areas and by acting as out-grower programmes for commercial farmers. The researcher’s observation is that through strategic interventions the programmes have potential to become commercial players in the industry. The following interventions were recommended from this study: Feasibility study of programmes and review of location selection before initiation. Providing supportive interventions for programme start-ups; Improved selection of programme beneficiaries; Improved structure of emerging farmers’ co-operatives; On-going and appropriate training for emerging ostrich farmers; The role of government and mentors needs to be defined; Reducing feed costs; Establishing programmes linkages to informal markets and facilitating increased self-consumption; Developing new export markets; Alternative finance for the no-income months; Alternative marketing channels to export markets; Representation of emerging farmers in the ostrich-industry leadership structures.

The aim of this study was to determine the quality of slaughtered ostrich meat and to evaluate the ostrich slaughter process, to determine whether ostrich meat are contaminated by the in-house slaughtering practices and if prevalence of microorganisms increase with the succession of the slaughter process. Furthermore, the presence of specific foodborne pathogens and spoilage organisms was explored by means of molecular and conventional methods to determine whether ostrich meat is a source of these microorganisms. Data obtained from this study provides some baseline information that could be used in future studies on system contamination and the extent of downstream processing steps in the production of ostrich meat. Antimicrobial resistance has become a growing area of concern in both human and veterinary medicine, it is therefore necessary that another aim of this study was to determine the antibiotic resistant pattern of Staphylococcus aureus in ostrich meat in order to establish whether Staphylococcus aureus strains isolated from ostrich meat samples show resistance to antibiotics

The aim of this study was to determine the quality of slaughtered ostrich meat and to evaluate the ostrich slaughter process, to determine whether ostrich meat are contaminated by the in-house slaughtering practices and if prevalence of microorganisms increase with the succession of the slaughter process. Furthermore, the presence of specific foodborne pathogens and spoilage organisms was explored by means of molecular and conventional methods to determine whether ostrich meat is a source of these microorganisms. Data obtained from this study provides some baseline information that could be used in future studies on system contamination and the extent of downstream processing steps in the production of ostrich meat. Antimicrobial resistance has become a growing area of concern in both human and veterinary medicine, it is therefore necessary that another aim of this study was to determine the antibiotic resistant pattern of Staphylococcus aureus in ostrich meat in order to establish whether Staphylococcus aureus strains isolated from ostrich meat samples show resistance to antibiotics

Thesis (MSc)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: The objectives of this study were threefold: (i) to investigate the effect of the replacement of pork fat with olive oil on the physico-chemical and sensory characteristics of ostrich polony; (ii) to investigate the effect of replacement of sodium tri-polyphosphate (STPP) with iota-carrageenan (CGN) on the physico-chemical and sensory characteristics of restructured cooked ostrich ham; and (iii) to investigate the effect of salt (NaCl) reduction on the physico-chemical and sensory characteristics of ostrich bacon. Five levels of olive oil were added to a polony formulation in 5% increments from 0 to 20%. Hardness, gumminess and shear force values decreased (P≤0.05) with increased levels of olive oil. The L* and b* values decreased (P≤0.05) with increased levels of olive oil producing lighter and more yellow products. Ostrich polony proved to have a favourable fatty acid profile in line with international recommended standards. A trained sensory panel found that the effect of increased levels of olive oil on had an effect (P≤0.05) on the sensory characteristics of colour; processed meat aroma and flavour; ostrich aroma; olive oil aroma; firmness and juiciness. A consumer panel found all the olive oil treatments to be acceptable. It can be concluded that olive oil can be used successfully for the production of low fat ostrich meat polony. In a restructured ostrich ham five decreasing levels of phosphate (0.7, 0.53, 0.35, 0.18 and 0%) were substituted with five increasing levels of carrageenan (0, 0.1, 0.2, 0.3 and 0.4%). The cooked yield of the restructured ostrich ham decreased significantly (P≤0.05) with decreased levels of phosphate. No tendencies in instrumental colour measurements with relation to decreased levels of phosphate were revealed. Hardness, cohesiveness and gumminess increased with decreased levels of phosphate. Ostrich ham had a favourable fatty acid profile and the latter is in line with international recommended standards. The trained sensory panel found that decreased levels of phosphate had a significant effect on the ham sensory characteristics of meat aroma and flavour; ostrich meat aroma and flavour and mealiness, but no significant effect on the spicy aroma and flavour. Three ham treatments with different levels of phosphate (0.7, 0.35 and 0%) were presented to a consumer panel. The consumer panel found the ham treatments with levels of 0.7 and 0.35% most acceptable. Carrageenan can be used to substitute phosphate at a level of 0.35% phosphate and 0.2% carrageenan in ostrich ham. Ostrich bacon was produces with five targeted salt (NaCl) levels of 3.5, 2.75, 2.0, 1.25, and 0.5%. Decreased salt levels had no significant effect on the L*, a* and b* values of the five treatments. Ostrich bacon had a favourible fatty acid profile. A trained sensory panel found that the effect of increased levels of salt had a significant effect on bacon sensory characteristics of ostrich aroma and flavour smoky bacon aroma and flavour and saltiness. A consumer panel found all the bacon treatments acceptable, with 2.75 and 2.0% being most likable. It can be concluded that, from a technical point of view, the salt content in ostrich bacon can be reduced successfully to produce ostrich bacon with low salt levels, although consumer preference for salt remains high. / AFRIKAANSE OPSOMMING: Die doelstellings van hierdie studie was drievoudig: (i) om die effek van die vervanging van varkvet met olyfolie op die fisiko-chemiese en sensoriese eienskappe van volstruispolonie te bestudeer; (ii) om die effek van die vervanging van natriumtripolifosfaat met iotakarrageenan op die fisikochemiese en sonsoriese eienskappe op die van hergestruktureerde volstruisham te bestudeer; en (iii) om die effek van sout (NaCl) vermindering op die fisiko-chemiese en sensoriese eienskappe van volstruisspek te bestudeer. Die polonie behandelings het uit vyf vlakke olyfolie bestaan wat by die polonie formulasie in 5% inkremente 0% tot 20% gevoeg is. Hardheid, taaiheid en skeurkrag het afgeneem (P≤0.05) met verhoogde vlakke van olyfolie. Die L*- en b*-waardes het afgeneem (P≤0.05) met verhoogde vlakke van olyfolie en uiteibdelik ‘n ligter en geler produk geproduseer. Die betrokke volstruispolonie behandelings het ‘n gunstige vetsuurprofiel wat in lyn is met internasionale aanbevole standaarde. ‘n Opgeleide sensoriese paneel het gevind dat die verhoogde vlakke van olyfolie ‘n betekenisvolle (P≤0.05) effek het op die kleur, geprossesseerde vleisgeur en -aroma, volstruis aroma, olyfolie aroma, fermheid en sappigheid. ‘n Verbruikerspaneel het gevind dat al vyf polonie behandelings aanvaarbaar is. Olyfolie kan dus suksesvol gebruik word in die produksie van laevet volstruispolonie. Hergestruktureerde volstruisham het bestaan uit vyf afnemende fosfaat vlakke (0.7, 0.53, 0.35, 0.18 and 0%) en vyf toenemende vlakke van karrageenan (0, 0.1, 0.2, 0.3 and 0.4%). Die opbrengs van gaar hergestruktureerde volstruisham het afgeneem (P≤0.05) met verlaagde vlakke van fosfaat. Geen betekenisvolle patroon is in instrumentele kleurmeting gevind nie. Hardheid, binding en taaiheid het toegeneem met afnemende fosfaat vlakke. Daar is bewys dat volstruisham ‘n gunstige vetsuurprofiel het wat in lyn is met internasionale aanbevole standaarde het. ‘n Opgeleide sensoriese paneel het gevind dat afnemende fosfaatvlakke ‘n betekenisvolle effek op die sensoriese eienskappe van volstruisvleis geur en aroma asook melerigheid, maar geen betekenisvolle effek op die speserygeur en -aroma gehad nie. Drie behandelings met verskillende fosfaat vlakke (0.7, 0.35 and 0%) is deur ‘n verbruikerspaneel vir aanvaaraarheid getoets. Die verbruikerspaneel het gevind dat die behandelings met 0.7 en 0.35% fosfaat aanvaarbaar was. Karrageenan kan dus gebruik word om fosfaat te vervang by ‘n vlak van 0.35% fosfaat en 0.2% karrageenan in volstruisham. Volstruisspek is geproduseet met vyf soutvlakke (NaCl), nl 3.5, 2.75, 2.0, 1.25 en 0.5%. Verlaagde soutvlakke het geen beteknisvolle effek op die L*-, a*- en b*-waardes van die vyf behandelings gehad nie. Volstruisspek het ook ‘n besonder gunstige vetsuurprofiel. ‘n Opgeleide sensoriese paneel het gevind dat die effek van verhoogde soutvlakke ‘n betekenisvolle effek het op die volgende sensoriese eienskappe: geur en aroma van volstruisvleis; geur en aroma van gerookte spek; en southeid. ‘n Verbruikerspaneel het gevind dat al die behandelings aanvaarbaar was, met die monsters met 2.75 and 2.0% sout as mees aanvaarbaar. In opsomming, die soutinhoud van volstruisspek kan uit ‘n tegniese oogpunt suksesvol verlaag word om ‘n produk met ‘n laer soutinhoud te produseer, alhoewel verbruikersvoorkeur vir sout hoog bly.

Magister Scientiae - MSc / The aim of this study was to determine the quality of slaughtered ostrich meat and to evaluate the ostrich slaughter process, to determine whether ostrich meat are contaminated by the in-house slaughtering practices and if prevalence of microorganisms increase with the succession of the slaughter process. Furthermore, the presence of specific foodborne pathogens and spoilage organisms was explored by means of molecular and conventional methods to determine whether ostrich meat is a source of these microorganisms. Data obtained from this study provides some baseline information that could be used in future studies on system contamination and the extent of downstream processing steps in the production of ostrich meat. Antimicrobial resistance has become a growing area of concern in both human and veterinary medicine, it is therefore necessary that another aim of this study was to determine the antibiotic resistant pattern of Staphylococcus aureus in ostrich meat in order to establish whether Staphylococcus aureus strains isolated from ostrich meat samples show resistance to antibiotics. / South Africa