Chicken as the first ingredient on the ingredient panel of a
dry extruded kibble has become more commonplace in the past
several years. Why chicken? It is likely because of its
popularity and ready supply rather than anything nutritionally
unique or special about chicken. Beef, lamb, fish and other
meats could be interchanged in this discussion just as
easily.
The bigger issue is whether formulating a dry petfood to
make a meat the first ingredient on the panel is only a
marketing ploy or if it truly imparts some enhancement to
nutrition and quality. The cynic will profess that it's all
about marketing.
Of course, there is some real truth to the notion that the
consumer is going to perceive that a food that is "made with
real meat" or has "chicken as the first ingredient" is a higher
quality product. And as our marketing brethren are eager to
remind us, in the market perception is reality.
It might not seem intuitive, but to begin answering this
question we need to determine exactly what constitutes chicken.
The best place to look is the Association of American Feed
Control Officials (AAFCO) manual wherein chicken, or rather
poultry, is defined as "the clean combination of flesh and skin
with or without accompanying bone, derived from the parts of
whole carcasses of poultry or a combination thereof, exclusive
of feathers, heads, feet and entrails."
Though one might deduce that chicken meal and chicken
by-product meal, since they are derived from chicken, would
count toward "chicken" as the first ingredient, according to
this definition and the labeling rules they don't. It's got to
be the real un-rendered chicken.
However, that doesn't mean that it is the pieces and parts
that you find in the grocery store. Purchasing chicken for
petfood applications occurs primarily in the same supply chain
as that of "hot dog or nugget meats."
This chicken is sometimes derived from hand trimming, but
more frequently from mechanical separation operations in which
the bones have been mechanically removed from the lean. This
latter procedure also removes the soft material from the marrow
of the bone, which can be high in fat.
The resulting chicken is then either chilled or frozen into
blocks. Use in petfood requires that it be brought to a
temperature just below freezing, but in a state that can be
pumped, a condition that often requires the use of steam.
Chicken as the first ingredient on the ingredient panel of a dry extruded kibble has become more commonplace in the past several years.From the definition, one might think that chicken is all
muscle and/or meat. The real ingredient, though, comes with a
great deal of water, fat and some incidental bone.
There is also no regulation on the nutrient composition of
this chicken, so depending on the materials being deboned and
the amount of steam it takes to pump the material, it can vary
widely. It is often in the range of 65-70% moisture, with
protein around 12-15%, however, and a minimum fat around 10%
(though the level of fat can be higher).
Lest we think that adding meat is a new concept in dry
petfoods, there were several regionally produced "meal" type
dog foods that used shreds of meat in their formulas long
before extrusion became popular.
More recently, several companies have marketed their foods
as made "with" real meat (e.g., chicken) in their name,
indicating that they contain at least 3% chicken. However, in
these cases, the chicken is listed well down the ingredient
panel and falls short of what it takes to be considered the
leading ingredient.
So, how much chicken might it actually take to reach the
top? In general, chicken must occupy around 15% of the formula
to go ahead of the other ingredients. From a formulation
standpoint this isn't too big an issue, though it does require
that the other ingredients compensate accordingly; namely, that
the number (but not the content) of protein meals and grains
are increased.
The bigger challenge is in the processing. The trick is to
manage the elevated moisture and fat from fresh chicken in the
conditioning cylinder or extruder so to achieve uniform mixing
and cooking. It is only in the last 15-20 years that
engineering of extruders and facilities, advances in
computerized process controls and improvements in sanitation
and meat handling equipment have been able to reach these
levels.
One might assume that having this much chicken in the
formula would contribute a substantial amount of protein to the
diet. However, in most instances chicken adds less than 10% of
the dietary protein.
Surprisingly, it may contribute more than 15% of the dietary
fat. While this lower protein contribution might seem
disappointing, the abundance of fat may help explain why high
chicken formulas are more palatable for both dogs and cats.
The digestibility of diets containing fresh chicken has also
been reported to increase slightly over diets that are
principally rendered chicken (Murray et al., 1997). A plausible
explanation for this is that the fresh chicken is processed or
cooked only once through the extruder, while the protein meals
(chicken [by-product] meal, fish meals, etc.) are cooked as
part of the rendering process and then again during extrusion.
This second round of cooking most assuredly leads to protein
damage and a reduction in digestibility.
In this day of natural, raw and home-prepared petfoods, the
notion of an extruded food with a high content of fresh chicken
isn't a big stretch. In fact, it may actually be a bridge to
the new petfood market.
It also gives credence to the notion that having chicken at
levels sufficient to be the first ingredient in the formula is
not merely hype because there are perceptible benefits to
palatability and digestibility of the diet. These benefits may
more than offset the increased challenges of procuring,
handling and processing a fresh chicken formula. While skeptics
can scoff at having chicken as the first ingredient on the
label, it does appear to be a true benefit for the pet and
certainly makes for easier communication of this value to the
pet owner.