Validation of Loss on Drying Methods in Pet Foods - AAFCO...2018/07/05 · AOAC 935.29 LOD in Malt 104 3 Convection Oven 7 2.55a 77 AOAC 969.35/925.45A LOD in Sugars 70 4 Vacuum Oven

Validation of Loss on Drying Methods in Pet Foods

Dr. Jane M. Caldwell 2018 AAFCO Annual Meeting

Fort Lauderdale, FL July 31, 2018

Pet Food Categories

• Dry pet food (15%) • Wet pet food (>30%) • Freeze-dried pet treats (

MoistureinDryPetFoodDeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods(Study1)

MethodNumber OfficialName Temp(⁰C) Time(hr) Equipment/Procedure N MeanMoisture

(%)

RelativeRecovery

(%)

AOAC930.15 LODforFeeds 135 2 ConvectionOven 33 8.03a* 112

AOAC935.29/945.15 LODinMalt 104 3 ConvectionOven 33 7.73a 108

AOAC950.46 LODinMeat 125 4 ConvectionOven 24 7.63a 106

AOAC2001.12(I) MoistureinFeed,Grain&Forage(MEOH/Formamide)

50 n/a Titration(KarlFischer) 24 7.18ab 100

ASTMD6869-03 MoistureinPlastics 130 var Titration(KarlFischer) 24 7.06ab 98

AOAC2001.12(II) MoistureinFeed,Grain&Forage(boilingMEOH)

66 n/a Titration(KarlFischer) 8 6.80ab 95

AOAC969.35/925.45A LODinSugars(Mod.) 70 4 VacuumOven 33 6.25b 87

*Levelsnotconnectedbythesameletteraresignificantlydifferent(p>0.05)

MoistureinDryPetFoodDeterminedByTitration(KarlFischer)andLoss-on-DryingOven(LOD)OvenMethods(Study2)

Moisture(%)

Sample AOAC2001.12(I) ASTMD6869-03 AOAC950.45B(b) AOAC945.15 AOAC969.35N=3 KarlFischer(Feed) KarlFischer(Plastic) Convection(125⁰C,4h) Convection(105⁰C,3h) Vacuum(70⁰C,4h)

1 6.57a 6.79a 6.46a 7.03 5.55

2 6.97a 7.31a 7.14a 7.60 5.79

3 7.50a 7.93 7.69a 8.41 7.18a

4 7.63a 8.19a 7.70a 8.99 7.67a

5 6.17a 5.78 6.07a 6.23a 4.49

6 6.03a 5.31 5.70 6.03a 3.79

7 7.80 6.86 7.53 7.46 5.80

8 7.20a 6.31 7.30a 7.06a 5.50

9 4.66a 3.93 4.28a 4.09 2.58

10 9.47a 9.16a 10.00 9.97 8.45

11 7.20a 6.73a 7.16a 7.07a 5.6112 7.33a 7.23 7.34a 7.48a 6.19

aMeanswithinarowwiththesameletterarenotstatisticallydifferent(p>0.05)fromKarlFischerAOAC2001.12(I)mean.

Observations for LODs in Dry Pet Food

•  KF (AOAC 2001.12) is LOD validation standard

•  Convection •  135⁰C too hot (118%) •  125⁰C okay •  104⁰C okay

•  Vacuum: too low at 4 h

MoistureinDryPetFood(Grain-free)DeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods*

Method Lab Temp(⁰C) Time(hr) Equipment/Procedure MeanMoisture

(%)

RelativeRecovery

(%)

AOAC930.15 X 135 2 ConvectionOven 8.72a** 110

AOAC930.15/925.10 Y 133 2 ConvectionOven 8.42ab 106

AOAC930.15 Z 135 2 ConvectionOven 8.18ab 103

AOAC991.02 Y n/a n/a Titration/Methanolextraction(KarlFischer)

7.93bc 100

AOCSCa2e-84 X n/a n/a Titration(KarlFischer) 7.79bcd 98

AOAC935.29 X 104 3 ConvectionOven 7.78bcd 98

NFTA2.2.2.5 Z 105 3 ConvectionOven 7.76c 98

AOAC934.06/925.45 Y 70 Overnight VacuumOven 7.48cd 94

ASTMD6869-03 Z 130 n/a Titration(KarlFischer) 7.24de 91

AOAC925.09 X 100 5 VacuumOven 6.75ef 85

AOAC969.35 Z 70 4 VacuumOven 6.24f 79

*TotalN=34;LabX&Yhad2N/method;LabZhad5N/method

**Levelsnotconnectedbythesameletteraresignificantlydifferent(p>0.05)

MoistureinDryPetFood(HighProtein/Meat)DeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods*


(%)

RelativeRecovery

(%)

AOAC930.15 Z 135 2 ConvectionOven 6.10a** 111

AOAC930.15 X 135 2 ConvectionOven 5.98ab 109

AOAC930.15/925.10 Y 133 2 ConvectionOven 5.82abc 106

NFTA2.2.2.5 Z 105 3 ConvectionOven 5.74bc 105

ASTMD6869-03 Z 130 n/a Titration(KarlFischer) 5.52cd 101

AOAC991.02 Y n/a n/a Titration(KarlFischer) 5.48cd 100

AOCSCa2e-84 X n/a n/a Titration(KarlFischer) 5.44cd 99

AOAC935.29 X 104 3 ConvectionOven 5.17de 94

AOAC934.06/925.45 Y 70 Overnight VacuumOven 4.98ef 91

AOAC925.09 X 100 5 VacuumOven 4.70fg 86

AOAC969.35 Z 70 4 VacuumOven 4.40g 80



MoistureinDryPetFood(Potato)DeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods*


(%)

RelativeRecovery

(%)


AOAC930.15 X 135 2 ConvectionOven 9.12ab 125

AOAC930.15/925.10 Y 133 2 ConvectionOven 8.90ab 122

NFTA2.2.2.5 Z 105 3 ConvectionOven 8.52bc 116

AOAC935.29 X 104 3 ConvectionOven 7.96cd 109

ASTMD6869-03 Z 130 n/a Titration(KarlFischer) 7.63d 104

AOAC934.06/925.45 Y 70 Overnight VacuumOven 7.56d 103

AOAC991.02 Y n/a n/a Titration(KarlFischer) 7.32de 100

AOCSCa2e-84 X n/a n/a Titration(KarlFischer) 7.24de 99





MoistureinDryPetFood(Economy)DeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods*


(%)

RelativeRecovery

(%)


AOAC930.15 X 135 2 ConvectionOven 8.20abc 106

NFTA2.2.2.5 Z 105 3 ConvectionOven 8.08ac 105

AOAC930.15/925.10 Y 133 2 ConvectionOven 7.76abcd 101

AOAC991.02 Y n/a n/a Titration(KarlFischer) 7.72abcd 100

ASTMD6869-03 Z 130 n/a Titration(KarlFischer) 7.50bd 97

AOCSCa2e-84 X n/a n/a Titration(KarlFischer) 7.37bcd 95

AOAC935.29 X 104 3 ConvectionOven 7.28de 94

AOAC934.06/925.45 Y 70 Overnight VacuumOven 6.99def 91



*TotalN=34;LabX&Yrunduplicatereps/method;LabZranquintuplicatereps/method


Observations for LODs in Dry Pet Food; part 2

Did NOT use KF standard for animal feed (1-15%) It depends…LAB and INGREDIENT variation

•  Grain-Free •  135⁰C might work (103-110%) •  104⁰C good (98%) •  Vacuum OVERNIGHT (94%)

•  High Protein •  KFs all close (99-101%) •  104⁰C good (94 & 105%) •  DID NOT RUN 125⁰C

Observations for LODs in Dry Pet Food; part 2

It depends… •  Potato

•  135⁰ too hot (122-126%) •  104⁰C hot (109-116%) •  Vacuum ON (103%)

•  Economy •  133⁰C great (101%) •  DID NOT RUN 125⁰C •  104 & 105⁰C okay (94 & 105%)

Validate with AOAC 2001.12

MoistureinSemi-MoistPetTreatsDeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods

MethodNumber OfficialName Temp(⁰C)

Time(hr)

Equipment/Procedure N MeanMoisture

(%)

RelativeRecovery

(%)


AOAC935.29 LODinMalt 104 3 ConvectionOven 34 24.08a 118

ASTMD6869-03 MoistureinPlastics 130 var Titration(KarlFischer) 34 21.12b 103

AOAC969.35/925.45A LODinSugars 70 4 VacuumOven 34 20.75b 102

AOAC991.02 MoistureinSemi-MoistPetTreats

n/a n/a MethanolExtractionTitration(KarlFischer)

25 20.43b 100


Glycerinandotherhumectantsintreats.

AOAC991.02titratesformoistureinsoft-moistandsemi-moistpetfoodscontaining20-30moistureandothervolatilematerials.

Goldstandardforthismatrix.

Samplesrangefrom17to26%moisture.

Observations for LODs in Semi-Moist Pet Treats

• LOD in Sugars (102%): How sweet it is! • Vacuum oven • 70⁰C • 4 hours

MoistureinWetPetFoodDeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods


(%)

RelativeRecovery

(%)

NFTA2.2.1.1/2.1.4 LODforForages,Silage,WetFeeds(Two-stepmethod)

55(105)

ON(3)

ConvectionOvens 20 76.64a 100

AOAC991.02 MoistureinSemi-MoistPetTreats(Two-stepmethod)

55(n/a) ON(n/a) ConvectionOvenMethanolExtractionTitration(KarlFischer)

20 76.54a 100


AOAC950.46B(b) LODinMeat 125 4 ConvectionOven 20 75.37a 98

AOAC930.15 LODforFeeds 135 2 ConvectionOven 20 75.35a 98

AOAC991.02 MoistureinSemi-MoistPetTreats n/a n/a MethanolExtractionTitration(KarlFischer)

20 71.76b 94


AOAC991.02titratesformoistureinsoft-moistandsemi-moistpetfoodscontaining20-30moistureandothervolatilematerials.

Observations for LODs in Wet Pet Food

•  Two-step methods for KF and LOD •  104, 125 & 135⁰C also 98% •  KF for semi-moist low (94%) •  More data needed.

MoistureinFreeze-DriedPetFoodTreatsDeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods


(%)

RelativeRecovery

(%)


50 n/a Titration(KarlFischer) 7 3.31a* 100

ASTMD6869-03 MoistureinPlastics 130 var Titration(KarlFischer) 7 2.86a 86


AOAC969.35/925.45A

LODinSugars 70 4 VacuumOven 7 0.77b 23

AOAC969.35/925.45D**

LODinSugars 60 18 VacuumOven 7 0.77b 23


**NodigestquartzsandusedinDmethod.

MoistureinFreeze-DriedPetFoodTreatsDeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods–Study2


(%)

RelativeRecovery

(%)




50 n/a Titration(KarlFischer) 7 4.30a 100


Observations for LODs in Freeze-Dried Pet Food Treats

•  Chewy.com • 

MoistureinDriedBeefSticksDeterminedbyTitration(KarlFischer)andLoss-on-Drying(LOD)OvenMethods

MethodNumber OfficialName Temp(⁰C)

Time(hr) Equipment/Procedure N MeanMoisture

(%)

RelativeRecovery

(%)


50 n/a Titration(KarlFischer) 7 13.66a* 100

AOAC930.15 LODforFeeds 135 2 ConvectionOven 7 13.37a 98



Discussion of Pet Food LOD Results

• Review data • Commentary period for labs/stakeholders • Suggestions for further studies • Can we make some conclusions/give guidance?

Dr. Jane Caldwell402-829-9858

[email protected]

Dr. Jane M. Caldwell402-979-1411

[email protected]

Karl Fischer (Moisture by Titration)

GOLD STANDARD: Reaction of iodine with water. Used for TRUE MOISTURE & NIR calibration

Not free of procedural issues……..

•  AOAC 2001.12 (I & II) (2005) – Moisture in Animal Feed, Grain and Forage (1-15%) •  AOAC 991.02 (1995) – Moisture in Soft-Moist & Semi-Moist Pet Treats (20-30%) •  ASTM D6869-03 (2011) - Moisture in Plastics (0.005-100%) •  AOCS Ca 2e-84 (1997) Moisture in Fats & Oils

AOAC 2001.12 (I) Moisture in Animal Feed, Grain and Forage (1-15%)

•  High-speed homogenization in vessel? •  Pre-homogenization outside vessel

•  MEOH/Formamide extraction (50⁰C)

•  Time in titration vessel not a factor

•  Run in triplicate •  Comparable to ASTM D6869-03

AOAC 2001.12 (II) Moisture in Animal Feed, Grain and Forage (1-15%)

•  Boiling MEOH (66⁰C) •  No obvious advantages over (I).

•  Small volume of water easy to release? •  Vapor pressure issues •  Never used

AOAC 991.02 – Moisture in Soft-Moist & Semi-Moist Pet Treats (20-30%)

•  MEOH extraction with titration

•  Shake 15 min @ room temperature

•  10 g

•  Results always low

•  Limited by time

ASTM D6869-03 - Moisture in Plastics (0.005-100%)

•  Used by global pet food giants

•  0.10 to 1.0 g (

AOCS Ca 2e-84 (1997) Moisture in Fats & Oils

•  5-25 g sample of fat or oil

•  Chloroform/methanol extraction

•  Electrometric end point

•  No time restrictions

Documents

Validation of Loss on Drying Methods in Pet Foods - AAFCO...2018/07/05 · AOAC 935.29 LOD in Malt 104 3 Convection Oven 7 2.55a 77 AOAC 969.35/925.45A LOD in Sugars 70 4 Vacuum Oven