The meat we eat: from a Food Security perspective

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1 The meat we eat: from a Food Security perspective Louw Hoffman Department of Animal Sciences lch@sun.ac.za

Food Security According to the 1996 World Food Summit, Food security exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their

2 Food Security According to the 1996 World Food Summit, Food security exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life. Food security is multi-faceted, and solutions to the growing global demand for food will involve finding new ways to increase sustainable agricultural productivity as well as augment the nutritional value of food via crops and livestock. Our program focus on animal products: meat

3 Food Security at SU Production activities Fresh meat Processed meat

4 sustainable agricultural productivity Production activities Research Focus sufficient, safe and nutritious food Fresh meat Processed meat nutritional value Increase production Decrease losses along value chain

5 Research focus Red Traditionally Farmed species Exotic meat Production activities Meat Poultry Fresh meat Farmed Wild fowl Farmed Processed meat Fish / aquaculture Wild Crayfish / abalone

Meat quality and composition GENERAL Quality colour texture juiciness flavour Chemical composition proximate fatty acid amino acid mineral myoglobin collagen Sensory Processed meat

6 Meat quality and composition GENERAL Quality colour texture juiciness flavour Chemical composition proximate fatty acid amino acid mineral myoglobin collagen Sensory Processed meat quality & composition decrease costs develop new products Fresh meat shelf life stability lipid oxidation protein oxidation colour stability microbiological stability minimise losses

7 STUDENT ACTIVITIES & RESEARCH PROJECTS

8 Meat Red Poultry Fish / aquaculture Traditionally Farmed species Exotic meat Farmed Wild fowl Farmed Wild Crayfish / abalone Cattle PhD: Dam size on productivity MSc: shelf life mince MSc: Informal abattoirs Res: organ meat Sheep MSc: effect of feedlot vs. free range MSc: Effect of breed on meat quality MSc (x2): Nutrition & production Res: Wet carcass syndrome Res: organ meat Pigs MSc: Production of cheaper polony

9 Extensive production system (Free range) Traditional method Animals roam freely (unlimited exercise/grazing) South Africa: sheep & cattle farming Cattle finished off in feedlots MSc project: lambs housed on a 10 hectare plot

10 Intensive production system (Feedlot) Confined to barns (no/limited exercise) Australia (Sheep farming + 16%, 2008) Aspect currently developing in RSA MSc project: lambs housed in 1 x 2m indoor pen from birth

11 Exercise Fiber type Transition sequence IIB IIA I Limited exercise Unlimited exercise

Sample collection and preparation Abattoir Samples were collected < 60 min post mortem Samples left

with Tissue Medium Muscle fiber direction perpendicular to cardboard surface Tissue mount soaked in

- 9 th rib, 50mm from midline Laboratory Stored at -80 C until analysis Cryostat Successive sectioned

12 Sample collection and preparation Abattoir Samples were collected < 60 min post mortem Samples left side of the carcass 5 mm x 5 mm superficial muscle tissue scalpel blade Mounted on cardboard square with Tissue Medium Muscle fiber direction perpendicular to cardboard surface Tissue mount soaked in iso-pentane Snap frozen in liquid nitrogen (-159 C) Semimembranosus Muscle location Longissimus dorsi - 9 th rib, 50mm from midline Laboratory Stored at -80 C until analysis Cryostat Successive sectioned 10 μm -23 C 60% relative humidity Mounted on a glass slide (no cover slip) Biceps femoris Longissimus dorsi

13 Type2A Fiber Type & Sensory Tenderness Correlation between Fiber Type IIA & Tenderness (First Bite) FIRSTBITE Figure 8 Positive Pearson s correlations (r=0.505; p=0.002) for Type IIA fiber and first bite

Meat Red Poultry Fish / aquaculture Traditionally Farmed species Exotic meat Farmed Wild fowl Farmed Wild Game PhD: Production potential in Namibia PhD (x2): Supply chain of formal &

14 Meat Red Poultry Fish / aquaculture Traditionally Farmed species Exotic meat Farmed Wild fowl Farmed Wild Game PhD: Production potential in Namibia PhD (x2): Supply chain of formal & informal game meat PhD: Health & safety MSc: Effect of harvesting on quality & losses MSc (x4): Production & quality of various species MSc: game meat products Ostrich Crayfish / abalone

15 Outcome from PhD in Sustainable Game Meat Production in Namibia

16 Transport Suppliers of processing materials Game meat supply chain Primary producers (game farmers) Hunting (Including field slaughter) Farm abattoir Abattoir Harvesting (Including field slaughter) Large scale processor Export Small scale processor Wholesaler Retailer Import Local consumers

17 Red Traditionally Farmed species Game Meat Poultry Fish / aquaculture Exotic meat Farmed Wild fowl Farmed Wild Crayfish / abalone Ostrich PhD: Freezing & thawing losses MSc (x2): Effect of lairage & bruising on quality & losses MSc: Modelling on growth and meat yield MSc (x2): Effect of nutrition, production & transport on quality MSc: Effect of diet on nutritional composition

18 >10% Thaw Loss

19 Thermodynamic principles of Freezing and Thawing Chemical composition? of Ostrich Meat Rate of Freezing Ice Crystal Formation Rate of Thawing Moisture uptake No standard for Freezing or Thawing of Ostrich Meat

20 Meat Red Poultry Traditionally Farmed species Exotic meat Farmed Wild fowl Chicken MSc: Comparison of free range and intensive production on quality MSc: Effect of diet on nutritional composition Fish / aquaculture Farmed Wild Wild fowl MSc: Composition of Egyptian geese MSc: Composition of Guinea fowl Crayfish / abalone

21 A Profile of South African Game Bird Meat 6 Treatments Descriptive Sensory Analysis Trained panel - 8 Judges 14 Attributes Instrumental analysis Statistical analysis 6 x 6 Design Univariate analysis Multivariate analysis 1. Egyptian Goose 4. Ostrich Fan Fillet 2. Guinea Fowl 5. Ostrich Moon Steak 3. Pekin Duck 6. Broiler Chicken AROMA Game Aroma Chicken Aroma Ostrich Aroma Beef Aroma Drip loss Cooking loss ph Colour Shear Force WBC FLAVOUR Game Flavour Chicken Flavour Ostrich Flavour Beef Flavour Metallic Flavour TEXTURE Initial Juiciness Sustained Juiciness Tenderness Residue (AMSA, 1995; Honikel, 1998)

22 DA PLOT - SENSORY

EGYPTIAN GOOSE FUTURE RESEARCH PROFILING OF SA GAME BIRD MEAT Sensory Analysis

Colour WBC Drip loss Cooking loss Shear Force GENDER Chemical Analysis Proximate Analysis

23 EGYPTIAN GOOSE FUTURE RESEARCH PROFILING OF SA GAME BIRD MEAT Sensory Analysis Instrumental Analysis Chemical Analysis Physical Analysis Carcass Yield ph Profiling Colour WBC Drip loss Cooking loss Shear Force GENDER Chemical Analysis Proximate Analysis Fatty Acid Composition Amino Acid Composition Mineral Composition (Fe) Proximate Analysis Fatty Acid Profile Haemoglobin Myoglobin Fe GRAIN SEASON Sensory Analysis Aroma Flavour Texture Instrumental Statistical Analysis Univariate Analysis Multivariate Analysis Correlation Analysis

24 Red Traditionally Farmed species Exotic meat Fish PhD: Quality of Snoek Meat Poultry Fish / aquaculture Farmed Wild fowl Farmed Wild MSc: Chemical composition of yellowtail MSc (x2): Comparison of quality of farmed vs wild yellowtail MSc: colour stability of tuna MSc: Nutritional value of shark meat MSc: Nutritional composition of snoek Crayfish / abalone

25 The determination of the nutritional composition and sensory quality of Mustelus mustelus meat for commercial use Smoothhound shark (Mustelus mustelus) is one of the five commercial shark species caught in South Africa o Cow shark o Soupfin shark o Blue shark o Mako shark 25

26 Nutritional Composition Cross Carcass Variation 5 anatomical sites 26

27 27

28 Proximate Composition Table 1. Preliminary results for cross carcass variation of proximate composition (n=5) A B C D E P value Moisture % Protein % Fat % Ash %

29 Yellowtail/Snoek

30 Meat Red Poultry Traditionally Farmed species Exotic meat Farmed Wild fowl Crayfish PhD: Quantifying fatty acid metabolism in crayfish MSc: Effect of production parameters on quality Fish / aquaculture Farmed Wild Crayfish / abalone Abalone MSc: Effect of diet composition to minimise weight loss & quality Res: Decrease in value due to blueing

BLUEING IN CANNED ABALONE (HALIOTIS MIDAE) L.C. Hoffman & E.F. Uys INTRODUCTION Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa e-mail: lch@sun.

Discolouring (blueing) on the epipodium and top layer of the mantle area in canned abalone has been an ongoing problem for the industry.

In a secondary trial, three samples of the epipodium from the light blue, dark blue and white groups were selected. All the samples were analysed for proximate, anion and cation composition.

midae) showing no discoloration (white abalone, left) as well as abalone with discoloration (dark blue and light blue abalone, right).

31 BLUEING IN CANNED ABALONE (HALIOTIS MIDAE) L.C. Hoffman & E.F. Uys INTRODUCTION Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa South Africa farms and exports approximately 1000 tons of abalone of which approximately 50% is canned. Discolouring (blueing) on the epipodium and top layer of the mantle area in canned abalone has been an ongoing problem for the industry. Twenty-four canned abalone samples were selected: 8 light blue abalone, 8 dark blue (substandard) and 8 with no discoloration (white abalone). In a secondary trial, three samples of the epipodium from the light blue, dark blue and white groups were selected. All the samples were analysed for proximate, anion and cation composition. The aim of this research is to identify the component(s) causing blue discolouration. Figure 1 Canned abalone (H. midae) showing no discoloration (white abalone, left) as well as abalone with discoloration (dark blue and light blue abalone, right). RESULTS & DISCUSSION There were only slight differences in the moisture, protein and lipid contents of the various groups (Table 1). Mineral results showed no difference in Zn levels, hence it can be deduced that Fe and Cu may be major contributing factors to discolouration in the epipodium. Results from the elemental analysis (Table 2) showed that the ratio of the sulphates (SO 4 2- ) and phosphates (PO 4 3- ) (blue:normal) were higher than expected in the affected abalone, and this strengthens the possibility of copper sulphate being responsible for the discolouration. Another interesting phenomenon is that the chlorine levels are 3 times higher in the normal abalone. Table 1 Proximate composition of canned abalone (H. midae) showing discoloration (dark blue and light blue abalone), as well as abalone with no discoloration (white abalone). Moist (%) Protein (%) Lipid (%) Fe (mg/100g) Cu (mg/100g) Dark blue abalone 75.5 a ± a ± a ± a ± a ± a ± 0.44 Dark blue (epipodium) Light blue abalone 75.4 a ± a ± a ± a ± ab ± ab ± 2.19 Light blue (epipodium) White abalone 74.3 a ± a ± a ± b ± b ± b ± 1.59 White (epipodium) Zn (mg/100g) Table 2 Cation and anion analysis (water extract) were done on normal and blue abalone. The ratio of blue:normal abalone is also calculated. Cation analysis (mg/l) Ca Mg Na K Blue abalone Normal abalone Ratio of blue:normal CONCLUSION Discolouration cannot be reversed once the product is completed therefore treatment of abalone prior to canning is important. Several causes of discolouration have been suggested. Improper handling and transport of abalone can cause internal bleeding resulting in a blue colour due to oxygenated hemocyanin. Anion analysis (mg/l) CH 2 OO - Cl - PO 3-4 SO 2-4 Blue abalone Normal abalone Ratio of blue:normal Stressed and moribund animals are also prone to have more sulphides available, and interactions between copper and these sulphides are also implicated in discolouration. These aspects warrant further research.

32 Community Interactions

33 Who are the partners? Stellenbosch Animal Sciences Food Sciences Microbiology Physiology Engineering Conservation, Ecology & Entomology Local Department of Agriculture (WC) CPUT TUT UP UWC DAFF International Padova University (Italy) Louisiana State University (USA) Carné Technologies (NZ)

34 Additional funders Red Meat Development Trust NRF EU: COOPERLINK travel & research grant DAFF Most contributions in kind Private Sector Most contributions in kind

35 What has OSP funding changed? Directly Improved infrastructure

36 What has OSP funding changed? Directly Improved infrastructure Increased post graduate participation Bursaries Project funds Increased collaboration with new disciplines Indirectly Functions as a source of seeding money

37 The road ahead Continue research projects with Padova University Finalise research agreement with Reunion Island: tuna & heavy metals Find new international partners Africa Europe Australasia New project with NRF New projects with RMRDT Attempt to leverage funds via THRIP

PART 1 UNDERSTANDING MEAT QUALITY

PART 1 UNDERSTANDING MEAT QUALITY Trends in meat consumption and the need for fresh meat and meat products of improved quality M D Aaslyng, Danish Meat Research Institute, Denmark - Eating meat for pleasure