It wasn't long ago that turkey (Meleagris gallopavo) was only eaten at Thanksgiving and Christmas. Turkey has now become a staple lunch meat, hot dog ingredient and alternative to ground beef. Its popularity has been due, in part, to its distinctive taste and healthful perception.
Pet owners superimpose these attributes onto ingredient and food choices for their pets. As such, turkey and turkey meal-containing petfoods are becoming more prominent. The turkey meat used to manufacture petfood is virtually identical to that used in hot dog production, so the nutrient information is relatively similar. However, nutritional information on rendered turkey is not as easily obtained, nor is the ingredient always available.
The primary reason is that most of the turkey going to the rendering plant is processed along with chicken and labeled for sale as poultry (by-product) meal. There are only a few companies that produce or trade turkey meal (for the sake of discussion, rendered turkey will be referred to as turkey meal whether it satisfies the definition of by-product or not).
There are several reasons why rendered turkey gets labeled as poultry meal. For starters, there hasn't been a consistent and sizable demand. Livestock customers haven't requested a separation of the raw material streams; to do so would only increase their cost of production. It's only been in the last decade or two that chicken meal rose to prominence due to demand by petfood producers.
Maybe the same will hold true for turkey if seasonal and supply issues can be resolved. That is to say, while turkey has certainly evolved from the days of the holiday campaigns, there is still an inconsistent and/or sporadic supply of turkey in some regions of the country, making it more expedient for most renderers to process raw material as it arrives without segregation. Given that most of the poultry meal in the market is a combination of turkey and chicken, a clever approach to handling the issue was recently presented to the AAFCO Pet Food Committee (PFC) for interpretation.
The notion was to proportionally separate the two ingredients according to the amounts of each that were processed together, and then label as Turkey Meal and Chicken Meal, respectively. The mere request is testimony to an existing demand for turkey meal. Unfortunately, the PFC at the mid-year meeting didn't quite agree with the concept, so it's back to the drawing board.
In general terms, turkey meal is a slightly darker golden brown color and has a "richer" aroma when compared to chicken meal. The nutrient composition is usually considered to be somewhat better than meat and bone meal; some have used turkey meal as a modest upgrade from meat and bone meal.
Conversely, the nutrient profile of turkey meal is slightly inferior to that of petfood-grade chicken meal. For example, turkey meal protein ranges from 62-65% and ash level ranges from 18-25%; whereas, petfood-grade chicken meal typically exceeds 65% protein with less than 17% ash. The slightly lower protein and higher ash content of turkey is primarily due to differences in bird size and how this affects the amount of soft material that is rendered.
Case in point, the larger size and frame of a turkey allow for more efficient removal of meat and other soft materials for the human edible and (or) hot dog markets, i.e., 78% of turkey ends up in the grocery meat case versus 72% of chicken. Thus, the raw material finding its way to rendering is, in general, lower in protein and fat and higher in bone (ash).
In general terms, the amino acid and fatty acid profile of turkey meal is very similar to that of chicken meal. It has become an urban legend that turkey induces a sense of calm and sleepiness after consumption due to a "high" level of tryptophan. This is supposedly due to the conversion of tryptophan to serotonin, the neurotransmitter thought responsible for a sense of calm and well being. However, the level of tryptophan in turkey meal is no greater than in chicken meal.
Only one paper has been published in which turkey meal was fed to dogs; unfortunately, the information in this work was confounded as the turkey meal was the base ingredient for a lamb meal analog. In vitro digestibility of turkey meal has been reported at 80-85% and the level of hydroxyproline, the principal amino acid in connective tissue, at around 2.5%. These are comparable to chicken meal, which would suggest that turkey meal digestibility, and effects on stool quality, should be comparable. It would be prudent, though, to confirm this assumption. How turkey meal affects palatability is not well documented.
Turkey meal merits its own identity, but suffers from a lack of definitive information. Several reputable suppliers currently merchandize turkey meal to the petfood industry, but availability is limited. Use might increase if research were conducted to determine the unique properties of turkey meal. This in turn could provide more incentive to increase supply by keeping more turkey and chicken separate in the rendering process.