petfood pro 4/2022

INGREDIENTS
Other biogenic amines mentioned before
like cadaverine and putrescine are known
to have an impact on the palatability of
finished pet food, but this topic will be
discussed deeper in the next section of
this article.
To avoid these consequences, it is important
to maintain the freshness and quality of
meat and meat products by avoiding
microbiological growth, thus protecting
materials as soon as possible from
evisceration, transport, and processing.
Biogenic amines are heat resistant and
acid resistant molecules, this means, that
once they are formed in the fresh crude
raw materials they will survive and stay
present in the final product produced with
those raw materials. ⅷ ⅸ In the Figure 2
below you can see a graphic representing
biogenic amine concentration (histamine,
putrescine, cadaverine and tyramine)
before and after autoclaving (elevated
temperature and high-pressure process).
As you can see the concentrations before
and after are quite comparable.
Figure 2: Biogenic amines concentration
before and after autoclaving.
Ideally, to control biogenic amines
growth it is necessary to inhibit the
microbial growth and the decarboxylase
activity of microbes. These are some
suggestions on how to do it:
• Use cold storage
• Frequent collection of raw materials
and limitation of storage time during
warm seasons
• Process the materials as soon as
possible
• Good hygiene practice. Ensure that
transport and processing equipment
are kept sanitized to reduce
microbial load
• Use freshness treatments with the
right organic acids' combination
able to: not affect palatability, not
increase ash content, control a
broad range of biogenic amines, not
causing pro-oxidation
Free Fatty Acids
Another consequence associated with
freshness decay is the increase of acidity,
or the formation of free fatty acids. In
this case, the origin is the hydrolyzation
of triglycerides by the action of the
enzyme lipase. ⅹ This process occurs in
fresh raw materials containing fats and
the formation of free fatty acids (FFA)
increases systematically in the crude raw
materials as the environment temperature
rises. Once the crude raw materials are
processed, to produce processed animal
protein (PAP) and fat, the FFA level should
not increase anymore over time.
Usually, FFAs are used as an indicator
of the freshness of a fat, oil, or PAP. The
higher the FFA level, the less fresh the
product is. Both parameters, FFA and
biogenic amines are also indicators of
quality of the supply chain and give
information about how the crude raw
materials are handled. There is still a lack
of knowledge regarding the potential
negative effects of elevated levels of FFAs
regarding the health of pets or impact on
the palatability and shelf life of finished
pet food products.
Kemin is currently developing a set
of trials to answer these questions,
especially the one related to high FFAs
and their impact on palatability and shelf
life of final pet food products. We hope to
share the outcome of these trials soon.
To the best of our knowledge there are,
at the moment, no legislation related to
maximum FFA levels allowed in pet food
or pet food raw materials. What we have
observed in the market is that pet food
producers tend to require and set their
own maximums limit towards their raw
materials suppliers. This is often based on
their own research/experience.
To control FFA formation, the same
suggestions as for biogenic amines
control mentioned before also apply
here since both freshness parameters
are caused by the same phenomenon,
microbial growth.
By experience we suggest treating as soon
as possible sensitive raw materials inside
the slaughterhouses with preservatives
like ALLINSUR or RENTERRA Kemin
product lines.
3. Factors impacting pet food
palatability with focus on
Biogenic amines
Loss of freshness can be initiated by
microbial degradation in the pet food
or in their initial crude raw materials
Figure 3 (below): Hydrolysis of triglycerides
to form free fatty acids.
Photos: sarahb-fotos.de
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Technology & Marketing