Oral presentation at the Annual Meeting of the European Federation of Animal Science (EAAP), 2000 (NL)

1. EFFECTS OF BEEF
BREED AND DIETARY
FAT SOURCES ON MEAT
QUALITY
Dr. Esra KURT
University of Istanbul
Faculty of Veterinary Medicine
Division of Food Hygiene and Technology

2. WHAT IS THE IMAGE OF RED
MEAT?

3. Red meat has
gained a poor
health image…
mainly because
of its fat content
both in terms of
quantity and
fatty acid
type….
WHAT IS
WRONG WITH
MY FAT?????
WHAT IS
WRONG WITH
MY FAT?????

4. The fatty acids deposited in beef
muscle and fat tissues are relatively
saturated, leading to a low P:S ratio
in the meat of approximately 0.1, the
ideal being about 0.4 (Department of
Health, 1994).

5. However,the ratio of n-6:n-3 fatty
acids is beneficially low,
approximately 2.0 which is in the
recommended range of 1-4
(Department of Health, 1994).

6. .....Therefore, the main reason for the
decline in the consumption of beef, pork
and lamb is related to health attributes..
….So, the fatty acid type is important for
the P:S and n-6: n-3 ratios...because
SFA raise blood cholesterol and PUFA
lower it….Also n-3 PUFA reduce blood
clotting while n-6 PUFA increase it…

7. AIMS
Improve the eating quality and
health attributes of beef in order
to reverse the current trend of
falling beef consumption.

8. To raise the
P:S ratio
whilst keeping
n-6:n-3 low
are required
to improve the
image of beef.

9. HOW?

10. ….By changing
dietary
ingredients which
are known sources
of long chain
polyunsaturated
fatty acids….

11. ….We examined two
breeds and three diets
for their effects on
fatty acid
composition and
susceptibility to lipid
oxidation, colour and
eating quality ….

12. E X P E R I M E N T A L D E S I G N
R e t a i l D i s p l a y
C o l o u r d e t e r i o r a t i o n d u r i n g d i s p l a y
T B A - t e s t a f t e r 4 , 8 , 1 1 d a y s d i s p l a y
F l a v o u r A n a l y s i s a f t e r 5 d a y s d i s p l a y
A g e i n g f o r 1 1 d a y s
L i p i d o x i d a t i o n i n d u c e d T B A t e s t
F a t t y a c i d c o m p o s i t i o n
V i t a m i n E c o n c e n t r a t i o n s
4 8 h P o s t s l a u g h t e r m . l o n g i s s i m u s d o r s i a n d p s o a s w e r e r e m o v e d f o r i n i t i a l t e s t s :
S l a u g h t e r
E v a l u a t i o n o f c a r c a s s c h a r a c t e r i s t i c s
p H e s t i m a t i o n a t 3 h a n d 4 8 h
F e d f o r 9 0 d a y s
C o n t r o l
L i n s e e d
L i n s e e d + F i s h o i l
3 6 A n i m a l s
1 8 H o l s t e i n x F r i e s i a n
1 8 P e d i g r e e W e l s h B l a c k s

13. RESULTS

14. There was a significant diet
x breed interaction for
carcass conformation
scores.

15. The effect of breed x diets on
conformation scores
Conformation Control Linseed Mix sig
____________________________________________
FriesianxHolstein 65.0b
42.5a
46.3a
*
Welsh Blacks 85.0a
95.0b
85.0a
*
________________________________

16. FriesianxHolstein animals
had average or lower than
average values for
conformation (between O+
and R) and fatness scores
(between 2O
and 2+
)
whereas Welsh Blacks had
better values for fatness
and conformation (R 4L).

17. The effect of breeds on fatness
scores
Fatness FriesianxHolstein Welsh Blacks sig
_____________________________________________
Means 63.2a
83.0b
***
_______________________________________

18. The effect of diets on fatness
scores
Fatness Control Linseed Mix sig
_____________________________________________
Means 81.7c
65.8a
71.9ab
*
_______________________________________

19. Diet and
breed
influenced the
fatty acid
composition
of beef
muscle.

20. The animals fed dietary
Linseed had
significantly higher
levels of C18:3n-3
whereas the animals
fed Linseed+Fish oil
diet had increased
levels of C18:3n-3,
EPA and DHA..

21. The effect of diets on fatty acid
composition of PL in m.longissimus dorsi
(percentage by weight of total fatty acids)
Fatty acid Control Linseed Mix sig
_______________________________________
C18:2n-6 12.89b
10.47a
10.0a
***
C18:3n-3 2.60a
4.33c
3.45b
***
C20:5n-3 (EPA) 0.30c
0.36b
0.48a
***
C22:5n-3 (DPA) 3.95a
4.14ab
4.39b
*
C22:6n-3 (DHA) 0.47a
0.58b
1.11c
***
Total Fatty acid 94.62b
93.55ab
92.8a
***
_______________________________________

22. There were clear
differences in fatty acid
composition between the
two breeds on a
percentage basis, Welsh
Blacks having higher
percentages of -linolenic
acid, EPA and DHA….

23. The effect of breeds on fatty acid
composition of PL in m.longissimus dorsi
(percentage by weight of total fatty acids)
Fatty acid FriesianxHolstein Welsh Blacks sig
_______________________________________
C18:3n-3 3.06 3.85 ***
C20:5n-3 (EPA) 2.49 3.41 ***
C22:5n-3 (DPA) 3.87 4.45 ***
C22:6n-3 (DHA) 0.68 0.76 ns
Total Fatty acid 94.05 93.26 ns
_______________________________________

24. However, the n-6:n-3 ratio
was greatest in controls (P<0.001)
There were no significant diet
effects on P:S ratio across the
treatments.

25. The P:S ratio was greater
and n-6:n-3 ratio was lower
in Welsh Blacks than
Friesian x Holstein….
So, Welsh Blacks had slightly
‘healthier’ meat….

26. Effect of breed on P:S and n-6:n-3 ratios
in FriesianxHolstein and Welsh Black
cattle fed on diets containing different fat
sources
FriesianxHolstein Welsh Blacks sig
_______________________________________
P:S ratio 0.11 0.15 *
n-6:n-3 ratio 2.58 2.02 ***
_______________________________________

27. All induced TBA and
TBARS test values
from different diets
and breeds were
under the value of 1.0
which indicates that
the meat would be
acceptable to most
consumers

28. Development of fat rancidity in
m.longissimus dorsi muscles from
Welsh Black’s fed different diets

29. In both breeds the
linseed plus fish oil
mix diet gave the
best colour shelf-life
although the
difference between
control and mix diet
was not significant in
Welsh Blacks...

30. The effect of time displayed upon
saturation of MA packed m.longissimus
dorsi steaks from FriesianxHolstein
animals fed different diets

31. The effect of time displayed upon
saturation of MA packed m.longissimus
dorsi steaks from Welsh Black animals
fed different diets

32. Overall, the steaks from Friesian
x Holstein animals were slightly
more stable than the steaks from
Welsh Blacks...

33. The effect of diet in
terms of flavour profile
was not significant
except that,
surprisingly, fishy
notes were significantly
greater in the control
diet than in the other
diets..

34. Overall,
the
linseed
plus fish
oil
seemed
to be
liked the
most.

35. The effect of
breed in terms of
flavour profile
was not
significant except
thoughness notes
were significantly
greater in Welsh
Blacks.

36. The interaction between diet and
breed was significant for some
eating quality traits.
Beef flavour, flavour liking and
overall liking scores were higher
in the Welsh Blacks fed the mix
diet and Friesian x Holstein fed
control diet.

37. CONCLUSIONS

38. The meat from both
breeds fed the linseed
containing diets would
make an important
nutritional contribution
to the consumers diet
and would have
acceptable meat quality
attributes.

39. Total lipid of Welsh Blacks
had higher percentages of
C18:3n-3 and other PUFAs.
The breeds had different
capacities to deposit n-3
PUFA in m.longissimus
dorsi.

40. This was not
because WB had
less total lipid but
their
phospholipids
contained more
n-3 and fewer n-6.

41. It is possible that this effect is
due to a difference in muscle
fibre type between the breeds.

42. The differences in fatty acids did
not increase TBA values or
markedly influence colour shelf
life

43. There were also no clear
breed effects on flavours
apart from the
interaction effect whereby
Friesianx Holstein fed the
control and Welsh Black
given the mix diet had the
highest beef flavour scores...

44. There is no clear
explanation
for lower
toughness score
in Friesian x
Holstein
compared
with Welsh
Blacks...

45. However, the
dairy breed had
significantly
more marbling
fat and this
has been shown
to be a positive
factor in
tenderness….

46. THANK