petfood pro 4/2021

processing
(filling and emptying). On the other
hand, drying usually entails an integrated
solution with upstream and downstream
process steps provided by the customer.
The infrared system is individually
designed after a determination of the
technical requirements. In pet food
sterilization, microbiology is relevant,
because a microbiological protocol
is required as to which impurities the
product has. Other factors include the
size of the product, the bulk density, the
input and output moisture, and perhaps
whether the product has a special
ingredient that is thermally sensitive (this
could be for example a product with a
high sugar content).
Customizing temperatures and
times
In the case of specific requests, where
requirements involve particular
temperature regulation from the
FoodSafety-IRD, new solutions are sought.
Jan Hendrik Ostgathe describes one: "A
so-called press cake may be processed
at a maximum of 70 degrees Celsius so
as not to destroy valuable proteins. For
the press cake, seeds are pressed, the oil
is extracted, and what remains is a kind
of cake batter that contains proteins and
nutrients. Since oils and moisture are still
present after this procedure, the dough
must be dried to a residual moisture
content of less than five percent to allow
for storage and further processing. This
product is used as an additive to pet
foods because of its valuable nutrients.
In collaboration with our customers,
we often carry out trials with modified
temperatures and dwell-times and then
have laboratories test the effects of
these adjustments on the product – in
In the FoodSafety-IRD, infrared technology is used to sterilize and dry dog food
this case on the valuable protein. For the
press cake, we were able to modify the
temperature and drying time so that the
protein was retained.”
Steam processing affects
product properties
An alternative process for sterilization
and pasteurization of feed is the common
steam process. Saturated steam is
applied to the respective product. For
the process to be effective here, higher
temperatures are involved, but these
in turn have a greater impact on the
product’s properties. The product is thus
affected: the color changes, ingredients
volatilize, and the overall appearance and
consistency deteriorate. With the infrared
process, on the other hand, product
properties remain nearly unaffected.
Further, infrared is a natural application
that does not use gases or chemicals
commonly used in other treatment
processes to eliminate microorganisms.
Another positive aspect of infrared light
is its significantly higher efficiency due to
direct energy input. Compared with a hotair
roaster, for example, which is operated
with gas and has higher CO 2
emissions
due to combustion, the infrared rotary
drum can be operated with renewably
generated electricity
The time needed for cleaning after
each product change is considerably
reduced due to fast, easy access to the
rotary drum – and thus down-times
throughout the entire plant are reduced.
"Flexibility is the most important feature
of our infrared system," emphasizes Jan
Hendrik Ostgathe. "Numerous products
in various forms from a wide range of
food sectors can be processed. The focus
is on the product, and the machine is set
up according to that product’s specific
requirements. We often first test and
develop the appropriate treatment in
our in-house technical center, checking
temperatures, times and product
properties and then setting the right
parameters in consultation with the
customer."
Technology & Marketing
The FoodSafety-IRD from Kreyenborg
For more information
www.kreyenborg.com
Issue 4 2021
27