Street Pork Vendors' Hygiene and Safety Practices and Their Determinants in the Cape Metropole District, South Africa.

South Africa's rapid urbanization and high unemployment rates pushed people into street food vending as an alternative source of livelihood. Hygiene and food safety have become a concern under these circumstances owing to foodborne illnesses and associated deaths. A survey tool with 38 structured questions was administered to 172 to assess pork vendors' hygiene and safety practices and identify their determinants in five low-income high-density suburbs of the Cape Metropole District, South Africa. Overall, vendors washed their hands before and after handling meat (66% of respondents) and cleaned the working area daily (51%), pork storage area daily (60%), and utensils and equipment before and after use (36%) with most of them using detergents as the main cleaning agent (70%). A quarter of the interviewed vendors experienced meat spoilage during storage, and 80% had no training in hygiene and safe food handling. The marginal effects of logistic regression findings showed that vending income increased the vendor's probability to wash hands, and clean vending stalls, storage areas, utensils, and equipment. The likelihood of vendors cleaning pork storage areas, utensils, and equipment increased with the increase in female participants. The likelihood of hand washing and vending stall cleaning increased by 1% for each extra year of schooling. Strategies aimed at improving meat hygiene and safety practices of vendors in the surveyed areas should target vulnerable groups, especially less educated females depending solely on vending income.

Effect of sex (ram or wether) and short duration, high volt electrical stimulation on tenderisation of Longissimus thoracis et lumborum and Semimembranosus muscles derived from Boer Goat and large frame Indigenous Veld Goat.

This study determined whether castration and electrical stimulation (ES) influenced chevon tenderness and related physiological characteristics in Boer Goat (BG; n = 36; 21 bucks and 15 wethers) and large frame Indigenous Veld Goat (IVG; n = 41; 21 bucks and 20 wethers). Half of buck and wether carcasses were ES (20s, 400 Volts peak, 5 ms pulses at 15 pulses/s) 10 min post-mortem. Dressed carcasses were chilled (4 °C within 1-h post-mortem). pH and temperature decline, % drip loss, sarcomere length (SL), myofibril fragmentation length (MFL; 1- and 4-days post-mortem), Calpain-1, -2 and calpastatin activities (1- and 24-h), Warner-Bratzler shear force (WBSF; 1-day post-mortem) and sensory attributes (tenderness and juiciness; 4-days post-mortem) were measured on Longissimus thoracis et lumborum (LTL) and Semimembranosus (SM) muscles. ES carcasses had significantly lower pH irrespective of sex or breed. Buck LTL and SM were less tender (P ≤ 0.05) supported by longer MFL and higher calpastatin activity (P < 0.05), than wether muscles. ES LTL were more tender (WBSF and sensory) (P ≤ 0.001) while ES SM were less affected (P = 0.055). ES caused lower Calpain-1 activity in the LTL. SL do not support cold shortening and calpastatin played a major role in the tenderisation of chevon early post-mortem. A longer ageing period is recommended for goat meat in general to achieve acceptable levels of tenderness.

Quality and safety of pork sold in the informal urban street markets of the Cape Metropole, South Africa.

Pork in the informal market significantly contributes to food, nutrition and income security in low-income countries' urban areas but is a safety concern to value chain actors and public authorities due to potential contamination by pathogens. To evaluate the physicochemical quality, microbial and oxidative profiles of pork sold from the informal urban street market, 50 samples were collected from 40 street vendors and 10 supermarkets in five different low-income, high-density suburbs in the Cape Metropole District, South Africa. Results showed no differences (P > 0.05) in pH, colour, proximate attributes (except for lipid content), antioxidant activity, lipid oxidation, and Escherichia coli counts in pork collected from the formal and informal markets, and open-air and enclosed market stalls. Lipid content, Enterobacteriaceae, and total bacterial counts of pork collected from the informal market were higher (P ≤ 0.05) than those from the formal market. Positive cases of Listeria monocytogenes (6-8%) and Salmonella spp. (4%) were reported for pork sampled in the informal market, especially in open-air stalls. It was concluded that higher levels of microbial contamination in the informal market, particularly in open-air stalls compared to the formal market require constant monitoring, provision of appropriate market infrastructure, and hygiene behaviour change of vendors to ensure pork safety.

Fatty acid and oxidative shelf-life profiles of meat from lambs fed finisher diets containing Acacia mearnsii leaf-meal.

Five diets containing Acacia mearnsii leaf-meal (AMLM; 0, 50, 100, 150 and 200 g/kg DM) substituted for Triticum aestivum bran were fed to lambs for 42 days. The effect of diet and retail display period on meat fatty acid (FA) composition (day 1); colour, antioxidant activity, myoglobin and lipid oxidation (day 1, 3, 5, 7 and 9); protein oxidation (1, 3 and 7 d) and instrumental tenderness (day 1, 5 and 10) were evaluated. Dietary AMLM linearly decreased (P ≤ 0.05) individual (14:0, 16:0, 18:0) and total saturated FA and increased (P ≤ 0.05) trans(t)-monounsaturated FA (MUFA) mainly t10/t11-18:1, individual and total conjugated linoleic acids, n-3 and n-6 polyunsaturated FA (PUFA) contents. The contents of cis(c)-MUFA, mainly c9-18:1, exhibited a quadratic response reaching a minimum at 50 g/kg AMLM (P ≤ 0.05). Meat antioxidant on day 9 was higher (P ≤ 0.05) for diets containing ≥100 g/kg DM AMLM compared to the other diet × retail display period interactions. Relative to the other interactions, meat redness values were lowest on day 7 and 9 for AMLM diets containing ≥150 g/kg DM (P ≤ 0.05). Dietary addition of AMLM increased (P ≤ 0.05) meat lightness and oxymyoglobin, and reduced (P ≤ 0.05) TBARS and instrumental tenderness values. However, oxymyoglobin values declined (P ≤ 0.05) over the retail display period, while lightness, metmyoglobin, TBARS and carbonyls increased (P ≤ 0.05). Results indicate that AMLM up to 200 g/kg DM in lamb finisher diets, improves meat fatty acid composition, tenderness, and lipid shelf-life.

Production and meat quality attributes of lambs fed varying levels of Acacia mearnsii leaf-meal as replacement for Triticum aestivum bran.

The study evaluated the effects of substituting increasing levels of Acacia mearnsii leaf-meal (AMLM) for Triticum aestivum bran in lamb finishing diets on growth, carcass, and meat quality attributes. Forty, 3-months-old lambs with an average live weight of 25.7 ± 1.60 kg were allocated to one of the five dietary inclusion levels of AMLM (0, 50, 100, 150 and 200 g/kg DM; n = 8) in a completely randomised design for 42 days. Dry matter intake, average daily gain, feed efficiency, carcass weights, dressing percentage and income over feed costs exhibited quadratic (P ≤ 0.05) responses to the addition of AMLM peaking at 100 g/kg DM inclusion level. Meat ultimate pH, moisture and lightness increased linearly (P ≤ 0.05) while intramuscular fat and shear force declined linearly (P ≤ 0.05) with increasing levels of AMLM. In conclusion, AMLM can replace up to 100 g/kg DM of T. aestivum bran in lamb finisher diets without impairing meat production and quality.

Sustained Effects of Muscle Calpain System Genotypes on Tenderness Phenotypes of South African Beef Bulls during Ageing up to 20 Days.

The most important factor that determines beef tenderness is its proteolytic activity, and the balance between calpain-1 protease activity and calpastatin inhibition is especially important, while contributions can also arise from calpain-2 and, possibly, calpain-3. The meat ageing process itself affects these processes. To determine whether genotypes in the calpain-calpastatin system can enhance tenderness through a 20-day ageing period, South African purebred beef bulls (n = 166) were genotyped using the Illumina BovineHD SNP BeadChip through a gene-based association analysis targeting the cast, capn3, capn2 and capn1 genes. The Warner-Bratzler shear force (WBSF) and myofibril fragment length (MFL) of Longissimus thoracis et lumborum (LTL) steaks were evaluated between d 3 and d 20 of ageing, with protease enzyme activity in the first 20 h post-mortem. Although several of the 134 SNPs are associated with tenderness, only seven SNP in the cast, capn2 and capn1 genes sustained genetic associations, additive to the ageing-associated increases in tenderness for at least three of the four ageing periods. While most genomic associations were relatively stable over time, some genotypes within the SNP responded differently to ageing, resulting in altered genomic effects over time. The level of ageing at which genomic associations are performed is an important factor that determines whether SNPs affect tenderness phenotypes.

Differences in Meat Quality of Six Muscles Obtained from Southern African Large-Frame Indigenous Veld Goat and Boer Goat Wethers and Bucks.

Various meat quality characteristics of six muscles (Longissimus thoracis et lumborum (LTL), Semimembranosus (SM), Biceps femoris (BF), Supraspinatus (SS), Infraspinatus (IS), Semitendinosus (ST)) from large-frame Boer Goats (BG) and Indigenous Veld Goats (IVG: Cape Speckled and the Cape Lob Ear) were studied. Weaner male BG (n = 18; 10 bucks and 8 wethers) and IVG (n = 19; 9 bucks and 10 wethers) were raised on hay and natural grass, and on a commercial pelleted diet to a live weight of 30-35 kg. All goats were slaughtered at a commercial abattoir and the dressed carcasses were chilled at 4 °C within 1 h post mortem. The muscles were dissected from both sides 24 h post mortem and aged for 1 d and 4 d. Variations in meat characteristics such as ultimate pH, water holding capacity (WHC), % purge, myofibril fragment length (MFL), intramuscular fat (IMF), connective tissue characteristics, and Warner-Bratzler shear force (WBSF) were recorded across muscles. Bucks had higher lightness (L*) and hue-angle values, whereas wethers had increased redness (a*) and chroma values. The muscle baseline data will allow informed decisions to support muscle-specific marketing strategies, which may be used to improve consumer acceptability of chevon.

An Exploratory Study into the Influence of Sex on Body Measurements, Carcass Weights and Meat Yields of Giraffe (Giraffa camelopardalis angolensis).

Various body measurements and commercial carcass yields of relatively young (2½-6 yrs old) giraffe (Giraffa camelopardalis angolensis) were investigated to quantify the effect of sex there upon. Eight male and eight female giraffe were culled by standard practice in Namibia, where body and horn measurements were taken, before the carcasses were dressed. There were no significant differences between the mean dead weights of the two sexes (bulls = 691.1 kg; cows = 636.5 kg; p = 0.096), the only body measurements found to differ significantly were those of the forelegs, with the shoulder to hoof (p = 0.046) and the knee to hoof (p = 0.025) both being significantly longer in the bulls. The horn measurements were all found to be significantly larger in the bulls than the cows even at this young age. The neck weight as a percentage of the carcass weight was found to be significantly heavier for the bulls compared to the cows, however, the back percentage values were significantly heavier in the cows than the bulls. There was a strong positive correlation between the body weight and most of the body lengths, as well as between most of the individual body measurements. The giraffe used had an average age of 3.7 years old, and had therefore not yet reached their growth plateau, which may be why sex had no influence on most of the body measurements recorded.

Effect of Breed Types and Castration on Carcass Characteristics of Boer and Large Frame Indigenous Veld Goats of Southern Africa.

Weaner male Boer Goats (BG; n = 36; 21 bucks and 15 wethers) and large frame Indigenous Veld Goats (IVG; n = 41; 21 bucks and 20 wethers) were raised on hay and natural grass ad libitum and the recommended amount of commercial pelleted diet to a live weight between 30 and 35 kg. Carcass quality characteristics (live weight, carcass weights, dressing %, chilling loss and eye muscle area) were measured. The right sides of the carcasses were divided into wholesale cuts and dissected into subcutaneous fat, meat and bone. Large frame Indigenous Veld Goat (IVG) wethers were slightly lighter than the IVG bucks with no significant difference observed between BG. Wethers compared to bucks had higher dressing %, subcutaneous fat % in all primal cuts, intramuscular fat %, kidney fat % and, overall, slightly less bone %. Some breed-wether interactions were noticed: IVG wethers were slightly lighter than the IVG bucks, but the IVG bucks tended to produce higher % meat compared to other test groups. Judged on the intramuscular fat % characteristics, it seems as if wethers should produce juicier and more flavorsome meat compared to bucks.

Nutrient retention values and cooking yield factors for three South African lamb and mutton cuts.

BACKGROUND: Nutrient content of raw and cooked foods is important for formulation of healthy diets. The retention of nutrients during cooking can be influenced by various factors, including animal age, carcass characteristics and cooking method, and these factors are often unique to specific countries. Here the effects of animal age (lamb and mutton) and carcass cut (shoulder, loin and leg) combined with cooking method (moist heat and dry heat) on yield and nutrient retention of selected nutrients of South African sheep carcasses were studied. RESULTS: Cooking yields and moisture retention were lower for lamb loin but higher for lamb leg. Energy and fat retention were higher for all cuts of mutton compared with lamb, while higher retention values for cholesterol were recorded for lamb. Mutton retained more iron (P = 0.10) and zinc and also more vitamin B2 , B6 and B12 than lamb. Shoulder cooked according to moist heat cooking method retained more magnesium, potassium and sodium. CONCLUSION: Incorporating these retention and yield values into the South African Medical Research Council's Food Composition Tables provides a reliable reference to all concerned with nutrient content of food. It will also guide practitioners and primary industry to adjust animal production aimed at optimum nutrient content to specific diets. © 2017 Society of Chemical Industry.

The effects of animal age, feeding regime and a dietary beta-agonist on tenderness of three beef muscles.

BACKGROUND: Animal age as determined by number of permanent incisors (p. i.) is used in classification of beef carcasses to describe expected meat tenderness. However, animals differing in age are reared under different production systems (pasture or feedlot). In addition to age, other factors associated with particular production systems may also influence the palatability of meat. Therefore, the effects of age combined with feeding regime and the supplementation of a beta-agonist (zilpaterol) on the tenderness of M. longissimus lumborum (LL), M. semitendinosus (ST) and M. biceps femoris (BF) muscles were investigated. RESULTS: Tenderness of LL cuts was least affected by age but zilpaterol significantly decreased tenderness and ageing potential. Tenderness of high-collagen cuts (BF and ST) was negatively affected by age due to reduced collagen solubility. The effect of zilpaterol on these cuts was less significant and BF and ST cuts of the grain-fed A-age animals (0 p. i.) supplemented with zilpaterol (AZ) were more tender than the same cuts of grass-fed animals with 1-2 p. i. (AB-age) and grass-fed animals with 3-6 p. i. (B-age) according to Warner-Bratzler shear force (WBSF) and sensory analysis for tenderness. CONCLUSION: This study indicates that beta-agonists may influence variation in tenderness within an age class more than age or feeding regime. © 2016 Society of Chemical Industry.

Evaluation of three vacuum packaging methods for retail beef loin cuts.

Meat from beef T-bone cuts was packaged as follows: (1) Sub-primal cuts vacuum packaged (VP) in shrink bags, aged for 14 days, portioned, VP again and aged for a further 7 days (VPR), (2) individual T-bone steaks VP in shrink bags aged for 21 days (VPP), and (3) individual T-bone steaks aged in vacuum-skin packaging (VSP) for 21 days. VSP recorded less purge and showed higher oxymyoglobin values after 2 days and higher chroma after 3 days of aerobic display (P < 0.001) than VPR and VPP. Similar differences in colour stability were recorded for VPP compared to VPR.

Minimal electrical stimulation is effective in low stressed and well fed cattle.

Four groups of carcasses of eighty grain fed low stressed steers (~12 months old, 240 kg carcass weight) received no stimulation or had low voltage stimulation for 15, 45 and 90 s. M. longissimus was aged for 2 and 14 days at 2 °C. Shear force, sarcomere length, water holding capacity, purge, muscle fibre detachment, sarcomere breaks and colour shelf life over 7 days was measured. Both 45 s and 90 s stimulated samples completed rigor above 35 °C and 15s stimulated and non-stimulated samples below 35 °C. The greatest muscle fibre detachment occurred for 15s stimulated samples which were the most tender at all times with non-stimulated samples toughest at 2 days of ageing and all samples being tender at 14 days of ageing. The 45 and 90 s stimulated samples consistently exhibited a brighter red colour at 2 days of ageing with no differences in colour intensity for the samples aged 14 days.

The effect of vitamin D(3) supplementation on texture and oxidative stability of beef loins from steers treated with zilpaterol hydrochloride.

In this study, 10 young steers received no beta agonist (C), 50 animals all received zilpaterol hydrochloride (Z), with 1 group receiving Z while the other 4 groups received Z and vitamin D(3) at the following levels (IU/animal /day) and durations before slaughter: 7 million for 3 days (3D7M) or 6 days (6D7M), 7 million for 6 days with 7 days no supplementation (6D7M7N) and 1 million for 9 days (9D1M). LD samples were vacuum-aged 14 days post mortem, and repacked in high-oxygen modified atmosphere (70% O(2)/30% CO(2)) for a further 7 days. Parameters included Warner Bratzler shear force (WBSF), myofibril fragment length, thiobarbituric acid reactive substances, free thiol levels, muscle fat, and instrumental colour parameters. When allowing for a conversion period of vitamin D(3) to its active metabolites, supplementing the zilpaterol treated steers with a high dosage of vitamin D(3) (6D7M7N) resulted in improved colour stability, higher stability towards protein oxidation and lower stability towards lipid oxidation.