Extra water in mixer gives better pellets

Two diets for finishing pigs were used to determine the effect of adding
water into the mixer on processing characteristics and pellet
quality.

The researchers used a barley-based diet and a maize-based diet.
Both diets were produced without and with use of an expander.

Adding up
to 120 g water/kg into the mixer prior to steam conditioning and pelleting of
the barley-based diet, improved pelleting efficiency, pellet durability index
(PDI) and modified PDI (with five hexagonal nuts added into the tumbling box),
by 15, 10 and 10%, respectively.

When water was added into the mixer
prior to expanding the barley-based diet, PDI increased from 93 to 95% and
modified PDI from 91 to 94%.

The maize-based diet was processed with
motor load held constant to maximize feed mill output, and production rate held
constant to minimize energy use.

At a constant motor load and a constant
production rate, adding up to 30 g water/kg into the maize-based diet prior to
steam conditioning increased pelleting efficiency by 22% and 9%, PDI was
improved from 84 to 89% and from 79 to 87%, respectively.

Expander
conditioning of the maize-based diet increased PDI from 92% at none to 94% at 30
g/kg water addition.

Correspondingly, modified PDI was increased from 89
to 93% at adding none and 30 g water/kg into the mixer prior to expander
conditioning.

The overall conclusion from the experiment was that adding
water into the mixer before steam conditioning improved pelleting efficiency and
pellet quality in barley- and maize-based diet for finishing pigs.

The
full report can be purchased from ScienceDirect.