Chris R. Calkins, Ph.D.ccalkins1@unl.edu

402-472-6314

Impacts of Distillers Grains Feeding on Carcass and Meat

Characteristics

Attributes 0% 15% 30% P-value

Scorea Slight93 Small03 Small04 0.46

Fat, % 5.44 5.91 5.94 0.19

aSlight = 300 - 399, Small = 400 - 499

Marbling attributes (Calf-fed)

Attributes 0% 15% 30% P-value

Score1 Small20 Small22 Small30 0.89

Fat, % 5.44 5.91 5.94 0.19

1Slight = 300 - 399, Small = 400 - 499

Marbling attributes (Yearlings)

Marbling Score

y = -0.0277x2 + 1.3078x + 517.53

0

100

200

300

400

500

600

700

0 10 20 30 40 50 60

Mar

blin

g S

core

WDGS Level Marbling 0 518

10 52820 53330 53240 52650 514

Predicted Values

Linear P = 0.05Quadratic P = 0.05

% WDGS (DM basis)

Marbling vs. % Fat (Calf-fed)

P = 0.72

P = 0.99

Marbling vs. % Fat (Yearlings)

12th Rib Fat Depth

y = -8E-05x2 + 0.0039x + 0.4912

0

0.2

0.4

0.6

0.8

1

0 10 20 30 40 50 60

Fat

Dep

th, i

n

WDGS Level FAT0 0.49

10 0.5220 0.5430 0.5440 0.5250 0.49

Predicted Values

Linear P < 0.01Quadratic P = 0.04

% WDGS (DM basis)

Yield Grade

y = -0.0002x2 + 0.0129x + 2.848

00.5

11.5

22.5

33.5

4

0 10 20 30 40 50 60

Diet DM % WDGS

Yie

ld G

rad

e WDGS Level YG 0 2.85

10 2.9520 3.0230 3.0440 3.0150 2.94

Predicted Values

Interceptcov. P = 0.03 L P < 0.01≠ 0 P < 0.01 Q P = 0.06

Take-Home Points

• Fat thickness– Slight increase, then back to normal

• Yield grade– Slight numerical increase, then back to normal

• Marblilng– No negative effect on amount of marbling– No effect on “visualization” of marbling by the

USDA grader

b

a

b

Polyunsaturated Fatty AcidsPolyunsaturated Fatty Acids

Table 1. Weight percentage of fatty acids1 and fat content of ribeye slices (Longissimus thoracis) from steers fed WDGS finishing diets.

Dietary treatments2 Effects3

Fatty acid 0 15 30 P-value Linear Quadratic18:0 13.76b 14.13b 15.03a 0.02 <0.01 0.3318:1t 2.28b 2.61b 3.76a <0.01 <0.01 0.3518:1(n-9) 36.14a 34.66b 34.02b <0.01 0.46 0.2018:1(n-7) 3.20a 2.77b 2.41c <0.01 0.02 0.1318:1∆13t 0.10c 0.51b 0.64a <0.01 <0.01 <0.0118:2(n-6) 3.27b 4.22a 4.50a <0.01 <0.01 0.04Total Trans 2.87c 3.61b 4.86a <0.01 <0.01 0.33PUFA 4.90b 5.91a 6.23a <0.01 <0.01 0.29Omega 3 * * * * * *Omega 6 4.62b 5.60a 5.86a <0.01 <0.01 0.47Omega6:Omega3 * * * * * *1 Weight percentage values are relative proportions of all peaks observed by GC.2 Wet distiller’s grains plus solubles (%, DM basis).3Linear and quadratic response to WDGS level. a,b,c Means in the same row having different superscripts are significant at P ≤ 0.05 level.*not estimated.

Table 2. Weight percentage of fatty acids1 and fat content of tenderloin steaks (Psoas major) from steers fed WDGS finishing diets.

Dietary treatments2 Effects3

Fatty acid 0 15 30 P-value Linear Quadratic18:0 15.64 15.46 16.58 0.15 0.12 0.2218:1t 1.30 2.09 1.72 0.56 0.57 0.3718:1(n-9) 35.31a 34.55a 33.12b <0.01 <0.01 0.5618:1(n-7) 1.43a 1.37a 1.26b 0.01 <0.01 0.6218:1∆13t 0.17c 0.27b 0.41a <0.01 <0.01 0.2018:1∆14t 0.26a 0.28a 0.21b <0.01 0.05 0.0118:2(n-6) 3.08c 4.07b 4.80a <0.01 <0.01 0.66Total Trans 3.22 4.05 3.66 0.59 0.59 0.52PUFA 4.76b 5.80a 6.50a <0.01 <0.01 0.91Omega 3 0.42 0.41 0.38 0.19 0.07 0.90Omega 6 4.34b 5.23a 6.05a <0.01 <0.01 0.92Omega6:Omega3 10.09c 12.95b 16.25a <0.01 <0.01 0.711 Weight percentage values are relative proportions of all peaks observed by GC.2 Wet distiller’s grains plus solubles (%, DM basis).3Linear and quadratic response to WDGS level. a,b,c Means in the same row having different superscripts are significant at P ≤ 0.05 level.

Table 3. Weight percentage of fatty acids1 and fat content of top blade steaks (Infraspinatus) from steers fed WDGS finishing diets.

Dietary treatments2 Effects3

Fatty acid 0 15 30 P-value linear quadratic18:0 14.52 14.51 15.37 0.19 0.07 0.3518:1t 2.17c 2.79b 4.03a <0.01 <0.01 0.2918:1(n-9) 38.46 37.37 36.52 0.06 0.02 0.8618:1(n-7) 1.73a 1.58b 1.47b <0.01 <0.01 0.8018:1∆13t 0.08c 0.23b 0.37a <0.01 <0.01 0.9518:1∆14t 0.38a 0.38a 0.28b <0.01 <0.01 0.0818:2(n-6) 3.00c 3.96b 4.78a <0.01 <0.01 0.82Total Trans 4.36b 4.98b 6.15a <0.01 <0.01 0.37PUFA 4.60b 5.38ab 6.40a <0.01 <0.01 0.81Omega 3 0.35 0.31 0.28 0.19 0.06 0.97Omega 6 4.24c 5.07b 6.10a <0.01 <0.01 0.80Omega6:Omega3 12.50b 18.15b 24.65a <0.01 <0.01 0.651 Weight percentage values are relative proportions of all peaks observed by GC.2 Wet distiller’s grains plus solubles (%, DM basis).3Linear and quadratic response to WDGS level. a,b,c Means in the same row having different superscripts are significant at P ≤ 0.05 level.

Fatty acids at the duodenum - Corn vs WDGS

Vander Pol et al. 2007

Take-Home Points

• Increase in polyunsaturated fatty acids

30% discoloration

Infraspinatus, aged 7 d

Dis

colo

rati

on

Lose about 10% of shelf life

Infraspinatus, aged 42 dD

isco

lora

tio

n

Lose about 40% of shelf life

Choice Strip steaks, aged 7 d

Dis

colo

rati

on

Lose about 10% of shelf life

Choice Strip steaks, aged 42 dD

isco

lora

tio

n

Lose about 17% of shelf life

Take-Home Points

• Feeding WDGS causes a decrease in shelf life of beef

Why Reduced Shelf-life?

• Color is compromised by oxidation.

• The red pigment is oxidized to brown.

Rancidity (TBA) during Retail Display

a

ab

b

a

a

b

a

b

b

Top Blade Strip Loin

Take-Home Points

• Oxidation– Cattle fed WDGS yield meat more susceptible

to oxidation during retail display

• Fatty acid composition– Feeding WDGS causes an increase in

polyunsaturated fatty acids (the ones most likely to oxidize)

Eating Quality

• Trained Evaluation (Jenschke et al., 2007)– Cattle fed 0, 10, 20, 30, 40, and 50 WDGS– No effect on tenderness– No treatment effects noted for:

• Metallic, sour, charred, oxidized , rancid or livery

• However, research done with meat directly removed from the vacuum bag – no retail display (no exposure to oxygen)

Liver FlavorLiver Flavor

Frequency of Liver Flavor, Aged 7 d

0

2

4

6

8

10

12

0% WDGS -No E

0% WDGS +E

40% WDGS -No E

40% WDGS +E

% o

f p

anel

ists

no

tin

g l

iver

fla

vor

Day 0

Day 7

a aa

b

aaa

a

P < 0.07

Liver FlavorLiver Flavor

Frequency of Liver Flavor, Aged 28 d

0

2

4

6

8

10

12

0% WDGS -No E

0% WDGS +E

40% WDGS -No E

40% WDGS +E

% o

f p

anel

ists

no

tin

g l

iver

fla

vor

Day 0

Day 7a a

aa

a

b

aa

How to Address the Issue?

• Vitamin E is an antioxidant• Can be fed during the finishing phase• Question – can feeding high doses of

vitamin E help to address the issue?

• Study – WDG at 0, 20 or 40% -- With or without solubles -- With or without vitamin E

(fed at 500 IU/head/d for entire feeding period)

Corn40% WDGS

Fatty Acids Composition of Strip Loins[40% WDGS vs Corn]

PUFA Levels of Strip Loins[0, 20, & 40% WDGS]

0

1

2

3

4

5

6

7

8

PUFA

Wei

gh

t %

on

To

tal

fatt

y ac

ids

c

a

b

0% WDGS20% WDGS40% WDGS

Fatty Acids Composition of Strip Loins[40% WDG with or without DS]

No DS DS

Take Home Point

• The increase in polyunsaturated fatty acids comes from the distillers grains, not the solubles

Mineral Composition of Strip Loins[40% WDG vs Corn]

Corn40% WDG

Mineral Composition of Strip Loins[WDG with or with out DS]

No DS DS

Take Home Point

• The solubles cause an increase in the mineral content of the muscles – minerals which support oxidation

Oxidative Rancidity of Strip Loins, Aged 7 & 28 d, at 7 d Retail Display

[WDG vs Corn]

WDG

NO WDG

7 d Aged 28 d Aged

ab

ab

a b

a

b

Oxidation Rancidity of Strip Loins Aged 7 & 28d at 7 d Retail Display

[E vs No E]

E

NO E

7 d Aged 28 d Aged

ab

ab

Take Home Points

• Feeding WDG causes an increase in oxidation• The effect is mitigated through feeding of

vitamin E

% Discoloration of Strip Loins [0,20,40% WDG with or without DS or E]

0% WDG20% WDG40% WDG

Take Home Points

• Retail color stability is less a problem if the beef is aged just 7 d. When beef is aged longer, discoloration is an issue.

• Solubles exagurate the discoloration

Livery Flavor of Strip Loins, Aged for 7 & 28 d, at 7 d Retail Display [0 & 40% WDG with and without DS and E]

0% WDG40% WDG

Take Home Points

• Vitamin E? – Vitamin E helps to minimize problems with

oxidation, discoloration and off-flavors when fed with WDG

• What is the optimal level of vitamin E?

So...what is the optimal level of Vitamin E?

Recent research (n=90 steers)

Corn WDGS WDGS + 100E WDGS + 300E WDGS + 500E WDGS + 1000E

Aging – 7 d Aging – 21 d

Permeable film High O2 Low O2

Discoloration (%) Corn vs WDGS vs WDGS + vit E

a a

a

a

a

b

P < 0.10

b

ab

a

ababab

P < 0.05

After 4 d of retail display, feeding 1,000 IU of vit. E was superior to all other levels.

Discoloration (%) Corn vs WDGS vs WDGS + vit E

P < 0.05

a

b

a a a a

After 4 d of retail display, any level of vitamin E was sufficient to preserve color.

Redness (a*) Corn vs WDGS vs WDGS + vit E

a

ab

bb

ab

b

bb

b

a

b

ab

P < 0.05

After 3 and 4 d of retail display, feeding 1,000 IU of vitamin E helped preserve the read color.

Redness (a*) Corn vs WDGS vs WDGS + vit E

P < 0.05

a

a

aa aa

aa

aab

ab

ab

ab

abab

ab

bbc

bc

b

abcabc

c

c

After 2, 3, or 4 d of retail display, feeding 300 IU (or more) of vitamin E helped to preserve the red color.

Discoloration (%) of strip steaks aged 7d from steers fed WDGS, corn, and WDGS plus different concentrations of vit E displayed under different MAP.

MAP2 Treatment1 daysPermeable

film1 2 3 4

Corn 0D 1.60C 2.98B 3.94Aab

WDGS 0.88D 2.00C 3.13B 4.25Aa

100E 0.33C 1.89B 3.25A 3.92Aab

300E 0.54B 1.53B 2.77A 3.12Ab

500E 0D 1.34C 2.81B 4.06Aa

1000E 0C 1.08B 2.78A 3.17Ab

High O2

Corn 0.38Bb 0.19Bab 2.59A 2.01A

WDGS 1.75ABa 1.00Ba 2.62A 2.13A

100E 1.15Bab 0.57Bab 2.88A 2.59A

300E 0.98Bb 0.98Ba 2.94A 2.32A

500E 0Bc 0Bb 2.60A 2.81A

1000E 0.29Bbc 0.19Bab 2.59A 2.01A

Beef

dis

colo

rati

on

Table 4. Discoloration (%) of strip steaks aged 21d from steers fed WDGS, corn, and WDGS plus different concentrations of vit E displayed under different MAP.

MAP2 Treatment1 daysPermeable

film1 2 3 4

Corn 0.22C 1.16C 8.33B 14.51Aa

WDGS 0.19C 1.11C 6.11B 17.96Aa

100E 0C 0.46C 6.24B 14.24Aa

300E 0.22C 0.66C 5.89B 15.51Aa

500E 0.22C 0.50C 7.00B 14.18Aa

1000E 0B 0.38B 4.61A 7.87Ab

High O2

Corn 0 0 0 0.51b

WDGS 0B 0B 0B 12.40Aa

100E 0 0 0 0.49b

300E 0 0 0 0.18b

500E 0 0 0 0.18b

1000E 0 0 0 0.17b

Beef

dis

colo

rati

on

Discoloration (%) Corn vs WDGS vs WDGS + vit EDiscoloration (%) Corn vs WDGS vs WDGS + vit E

Discoloration (%) Discoloration (%) Corn vs WDGS vs WDGS + vit ECorn vs WDGS vs WDGS + vit E

10%

Discoloration (%) Corn vs WDGS vs WDGS + vit EDiscoloration (%) Corn vs WDGS vs WDGS + vit E

Take Home Points

• The ideal level of vitamin E depends on the packaging system to be used

• With minimal aging (7 d), little to no vitamin E is needed

• With extended aging, up to 1,000 IU/head/day are necessary.

Summary

• Carcass traits– No negative effects on marbling traits

• Meat traits– Increased PUFA– Decreased shelf life– Increased off flavors– Vitamin E helps to mitigate these issues– Levels up to 1,000 IU/head/d are needed