Factors affecting pellet quality

1. FactorsAffectingPelletQuality
MuhammadArslan Musa
M.Sc. (Hons.) PoultryScience
arslan2062@gmail.com

2. PelletQuality
 Ability to resist fragmentation and abrasion during handling
 Better pellet quality means minimum fines
 Feeding pellets improve feedintake, weight gain and FCR
 Maintenance of pellet integrity from mill to birds ingestion is important
 Maximum feed production with goodpellet quality

4. Factors
AffectingPellet
Quality
Formula
Particle size (Texture)
Water addition
Fat inclusion level
Conditioning
Die speed and die hole size
Cooling specifications

6. FeedFormula/
Recipe
 Different ingredients have different stickiness ability
 High protein = good pellet quality
 High stocking density = high production rate
 High protein + high stocking density = good pellet quality + high
production rate
 Fats = poor quality + better production rate
 Animal by-products = poor pellet quality
 High fiber = good pellet quality + slow production rate

7. Nutrient Effect on pellet quality Reason
Water/ Moisture Positive Role in starch gelatinization and protein
denaturation
Protein Positive Protein plasticization
Starches Positive Starch gelatinization
Fats Negative Cause coating of particles which
prevents moisture penetration and heat
transfer
Fiber Positive (if properly
grinded and
conditioned)

8. ParticleSize
 Propergrinding increase surface area
 Increase heat + moisture transfer
 More size reduction = better pellet quality

9. Moisture
Addition
 Properconditioning require moisture addition along with
temperature
 Moisture addition improves pellet quality
 High moisture can reduce friction between roll shell and die
holes
 High moisture = low friction = poor pellet quality

10. FatInclusion
Pre-pelleting fat addition prevent proper
gelatinization
It encapsulated particles and prevent heat and
moisture transfer
Reduce compaction of feed in die
It has extremely low FPQF (- 40)

11. Conditioning
 Optimum starch gelatinization and protein denaturation results in
good quality
 Positive impact of protein on pellet quality is much more important
than that of starch
 Higher temperature, more retention time and moisture addition upto
a limit improves pellet quality
 Minimum retention time in conditioner should be30 sec

12. Feed
Production
Rate
Pelletqualityusuallyreduced at higher production
rate
Reduced productionspeed is better for pelletquality

13. Pelletingdie
area
Thicker dies have positive impact on pellet quality
Most of starch gelatinization occurs when feed passes
through the dies
Less diehole diameter produced better pellets (reduce
production rate)
Increasing distance b/w roll shells and die (i.e. from 0.1
to 2 mm) increase pellet quality

14. Cooling
Cooler removes added moisture and heat from pellets
Quick cooling produced brittle and comparatively better pellets
Improper cooler function resulted in soft pellets

15. Measureof
PelletQuality
Pelletdurability Index (PDI)
Fines
Hardness
Size mg/pellet

16. PDI
 Percentageof pellets remains during test
 500 g sample ofcool andscreened pellets is putin a metal box called
“Tumbler can”
 Rotated at 50 rpm for 10 minutes or10 sec @600 rpm

17. FeedPellet
QualityFactor
 Developed by “BorregaardLignotech”
 Provide prediction about contribution of ingredients in pellet
quality
 PQFrangesfrom 0(poor) to 10 (good) except fat
 PQF for fat is -40
 Thetotal FPQF valueabove4.7 is indication of good pellet
quality

18. PQFofDifferent Ingredients