Poultry Carcass Waste Disposal
Biologically Safe and Environmentally Sound Poultry Carcass Waste Disposal for the 21st Century using Enzyme Technology
Published: December 30, 2011
By: SCOTT DARLING (Courtesy of Alltech Inc.)
Introduction
High intensity production agriculture in developed countries such as those in Western Europe and North America, are embroiled in environmental controversy. Air, surface water and ground water pollution threats are frequent newspaper headlines and subjects for litigation. Growing public concern for our environment, as well as increased local, state and federal regulations, present a tremendous challenge for the livestock and food production industries. Finding environmentally sound options for either using or disposing of waste products including dead animals and poultry is a large part of that challenge. Enzyme-processing is a safe and useful alternative for disposing of spent hens and normal, on-farm poultry mortality. A description of a new process and a discussion of how the resulting product can be used is the basis of this report.
Production of poultry solubles
OVERVIEW
We have developed an economical process system to digest whole poultry carcasses using proprietary equipment and new technology with the addition of carcass-digesting enzymes. This process system is designed for installation on the poultry farm and consists of a grinder and cone-bottom insulated tanks to hold the ‘hen solubles’. Dead hens are collected daily and subsequently ground.An enzyme cocktail (Alltech Feather Digest) is added to a carbohydrate catalyst which constitutes 20% of the hen solubles. This product is pumpable and has the appearance of oatmeal. Ground hens can be added on a daily or on an as-needed basis, until the tank is full. The hen solubles need 3 to 5 days to become completely digested, which reduces all meat, bone, connective tissue and feathers to a creamy consistency. The natural temperature rise is contained by the insulated tanks. Storage tank capacities as well as the number of tanks placed on the site is determined by the size of the farm and frequency of transport tanker pickup.
The ground hen solubles have no bad odor, there are no feathers or flies and thus the local environment is both biologically safe and inoffensive. The‘Digested Fermented Hen Solubles’ (DFHS) are stabilized and trials have shown DFHS to have a shelf life of up to 6 months.
Nutrient analysis, amino acid values and bacteriological information are in Tables 1 and 2. Values are compared for hen solubles using only Allzyme Feather Digest in the process and Allzyme Feather Digest plus a bacterial inoculant.
Table 1. Nutrient profiles (as received basis) of digested hen solubles processed with either Allzyme Feather Digest only or Allzyme Feather Digest plus a bacterial cocktail inoculant.
The process described
The DFHS are co-mixed with a cereal by-product carrier, extruded, dried, mechanically sized and packaged in a non-stop continuous production line. This system is an efficient use of labor, fuel and electricity to recycle animal carcass waste back into the livestock feed industry. It is a biologically safe and environmentally sound system, producing no discharge or other by-products. Following are descriptions of the various stages of production.
CEREAL BY-PRODUCT CARRIERS
Cereal by-products can be mixed with DFHS to aid in the drying process and produce a unique animal-vegetable blend of protein, fat and amino acids which can be used in diets of farm animals, pets and aquaculture species. Cereals we have used include rice hulls, rice flour, oat hulls, soybean hulls and soybean meal. Cereal by-product carriers should be chosen based on the intended use of the final product and prices of locally available ingredients.
Table 2. Amino acid analysis (%) of digested hen solubles processed with either Allzyme Feather Digest only or Allzyme Feather Digest plus a bacterial cocktail inoculant.
DRY CARRIER MIXING AND GRINDING
Up to four dry carriers can be proportionately mixed and then finely ground in a single operation. For example, soybean meal, soybean hulls and previously dried DFHS are mixed at a 2:1:1 ratio as they are fed into the hammer mill. These ratios can be tailored to obtain protein and fiber requirements desired in the final product analysis.
DRY CARRIER AND LIQUID DFHS MIXING
Using variable speed motors on a positive displacement pump and positive displacement air lock, the dry carrier and liquid DFHS are proportionately mixed via a high speed blender to produce a thick paste. The ratio can be adjusted to obtain an optimum carrier:liquid ratio, as well as final production rates.
WET EXTRUSION
The paste is ped immediately into a wet extruder which pushes the paste through a die, forming a series of long cylindrical ribbons similar to tooth paste. The ribbons are conveyed gently and laid uniformly and loosely across the face of the dryer apron.
DRYING
There are numerous dryers which are capable of removing excess moisture. Manufacturers of fluid bed dryers along with multi-pass belt dryers have been efficiently drying animal by-products for the last decade. Obviously, fuel and electrical efficiency are critical factors in choosing a drying system.We have identified and assembled in-line machines to form a multi-process production system to dry the DFHS and produce a livestock feed ingredient. Our production line is comprised of a three-pass drying system in which the air velocity, temperature and belt speed can be varied in each chamber. Each cereal carrier is unique in that each has a specific temperature and air velocity requirement for optimum moisture removal.
The pre-heat stage brings the temperature of the product up very quickly and flashes off exterior moisture. Air temperature and velocity are varied to fit the characteristic of the dry carrier as its original moisture content and physical characteristics determine moisture absorbency and drying efficiency.
The intermediate stage maintains optimum drying temperature and air flow through the product. Depth of the material can be increased by 20 to 30%. To increase drying efficiency, our system recycles the air to a point of maximum saturation before it is exhausted.
In the final heat stage, temperature can be raised or lowered to target final product moisture levels. The belt speed can also be varied, and the product depth is usually increased 20 to 30%. This stage also recycles saturated air to maximize efficiency.
The cooling stage lowers product temperature eliminating the possibility of sweating and subsequent sticking or bridging.
PARTICLE SIZING AND PACKAGING
Product is mechanically sized through a two pair roller mill to produce a particular particle size (microns).Aroller mill was our choice for size reduction, producing a textured product without excessive fines and excellent flowability. Dried product is immediately conveyed to a bulk load out or bag packaging line for shipment.
Alternative uses for DFHS
The DFHS can be land-applied to supply plant nutrients without any offensive odor. Alternatively, as is shown in Tables 1 and 2, the hen solubles (prior to co-processing with a cereal carrier) have a nutrient profile that can be useful in animal feed applications. Given the potential value of the DFHS, one should consider retaining the value of the DFHS by dehydration and using the product as dried DFHS livestock feed ingredient.
High intensity production agriculture in developed countries such as those in Western Europe and North America, are embroiled in environmental controversy. Air, surface water and ground water pollution threats are frequent newspaper headlines and subjects for litigation. Growing public concern for our environment, as well as increased local, state and federal regulations, present a tremendous challenge for the livestock and food production industries. Finding environmentally sound options for either using or disposing of waste products including dead animals and poultry is a large part of that challenge. Enzyme-processing is a safe and useful alternative for disposing of spent hens and normal, on-farm poultry mortality. A description of a new process and a discussion of how the resulting product can be used is the basis of this report.
Production of poultry solubles
OVERVIEW
We have developed an economical process system to digest whole poultry carcasses using proprietary equipment and new technology with the addition of carcass-digesting enzymes. This process system is designed for installation on the poultry farm and consists of a grinder and cone-bottom insulated tanks to hold the ‘hen solubles’. Dead hens are collected daily and subsequently ground.An enzyme cocktail (Alltech Feather Digest) is added to a carbohydrate catalyst which constitutes 20% of the hen solubles. This product is pumpable and has the appearance of oatmeal. Ground hens can be added on a daily or on an as-needed basis, until the tank is full. The hen solubles need 3 to 5 days to become completely digested, which reduces all meat, bone, connective tissue and feathers to a creamy consistency. The natural temperature rise is contained by the insulated tanks. Storage tank capacities as well as the number of tanks placed on the site is determined by the size of the farm and frequency of transport tanker pickup.
The ground hen solubles have no bad odor, there are no feathers or flies and thus the local environment is both biologically safe and inoffensive. The‘Digested Fermented Hen Solubles’ (DFHS) are stabilized and trials have shown DFHS to have a shelf life of up to 6 months.
Nutrient analysis, amino acid values and bacteriological information are in Tables 1 and 2. Values are compared for hen solubles using only Allzyme Feather Digest in the process and Allzyme Feather Digest plus a bacterial inoculant.
Table 1. Nutrient profiles (as received basis) of digested hen solubles processed with either Allzyme Feather Digest only or Allzyme Feather Digest plus a bacterial cocktail inoculant.
The process described
The DFHS are co-mixed with a cereal by-product carrier, extruded, dried, mechanically sized and packaged in a non-stop continuous production line. This system is an efficient use of labor, fuel and electricity to recycle animal carcass waste back into the livestock feed industry. It is a biologically safe and environmentally sound system, producing no discharge or other by-products. Following are descriptions of the various stages of production.
CEREAL BY-PRODUCT CARRIERS
Cereal by-products can be mixed with DFHS to aid in the drying process and produce a unique animal-vegetable blend of protein, fat and amino acids which can be used in diets of farm animals, pets and aquaculture species. Cereals we have used include rice hulls, rice flour, oat hulls, soybean hulls and soybean meal. Cereal by-product carriers should be chosen based on the intended use of the final product and prices of locally available ingredients.
Table 2. Amino acid analysis (%) of digested hen solubles processed with either Allzyme Feather Digest only or Allzyme Feather Digest plus a bacterial cocktail inoculant.
DRY CARRIER MIXING AND GRINDING
Up to four dry carriers can be proportionately mixed and then finely ground in a single operation. For example, soybean meal, soybean hulls and previously dried DFHS are mixed at a 2:1:1 ratio as they are fed into the hammer mill. These ratios can be tailored to obtain protein and fiber requirements desired in the final product analysis.
DRY CARRIER AND LIQUID DFHS MIXING
Using variable speed motors on a positive displacement pump and positive displacement air lock, the dry carrier and liquid DFHS are proportionately mixed via a high speed blender to produce a thick paste. The ratio can be adjusted to obtain an optimum carrier:liquid ratio, as well as final production rates.
WET EXTRUSION
The paste is ped immediately into a wet extruder which pushes the paste through a die, forming a series of long cylindrical ribbons similar to tooth paste. The ribbons are conveyed gently and laid uniformly and loosely across the face of the dryer apron.
DRYING
There are numerous dryers which are capable of removing excess moisture. Manufacturers of fluid bed dryers along with multi-pass belt dryers have been efficiently drying animal by-products for the last decade. Obviously, fuel and electrical efficiency are critical factors in choosing a drying system.We have identified and assembled in-line machines to form a multi-process production system to dry the DFHS and produce a livestock feed ingredient. Our production line is comprised of a three-pass drying system in which the air velocity, temperature and belt speed can be varied in each chamber. Each cereal carrier is unique in that each has a specific temperature and air velocity requirement for optimum moisture removal.
The pre-heat stage brings the temperature of the product up very quickly and flashes off exterior moisture. Air temperature and velocity are varied to fit the characteristic of the dry carrier as its original moisture content and physical characteristics determine moisture absorbency and drying efficiency.
The intermediate stage maintains optimum drying temperature and air flow through the product. Depth of the material can be increased by 20 to 30%. To increase drying efficiency, our system recycles the air to a point of maximum saturation before it is exhausted.
In the final heat stage, temperature can be raised or lowered to target final product moisture levels. The belt speed can also be varied, and the product depth is usually increased 20 to 30%. This stage also recycles saturated air to maximize efficiency.
The cooling stage lowers product temperature eliminating the possibility of sweating and subsequent sticking or bridging.
PARTICLE SIZING AND PACKAGING
Product is mechanically sized through a two pair roller mill to produce a particular particle size (microns).Aroller mill was our choice for size reduction, producing a textured product without excessive fines and excellent flowability. Dried product is immediately conveyed to a bulk load out or bag packaging line for shipment.
Alternative uses for DFHS
The DFHS can be land-applied to supply plant nutrients without any offensive odor. Alternatively, as is shown in Tables 1 and 2, the hen solubles (prior to co-processing with a cereal carrier) have a nutrient profile that can be useful in animal feed applications. Given the potential value of the DFHS, one should consider retaining the value of the DFHS by dehydration and using the product as dried DFHS livestock feed ingredient.
Feasibility studies are under way as to utilizing the DFHS as a liquid feed ingredient in manufacturing liquid supplements for beef, dairy and swine diets. Feed trials are currently on-going using DFHS as a protein, fat and amino acid source in liquid supplements.
Conclusions
Giving the world the types and quality of foods it wants in the quantities that will be needed an increasing challenge in the 21st century. Meeting this challenge will have to be done without risking environmental damage through inability to properly dispose of, or use, animal by-products. Finding alternatives that fit efficiently into the nutrient cycle as a whole will be critical. Enzyme-processing in combination with mechanical handling as described above removes a potential pollutant while creating a useful nutrient. In addition to spent hens, other areas with great potential are enzymatic digestion and recycling of hatchery waste, swine farrowing waste and normal swine mortality waste. I am currently working with the Nebraska Department of Environmental Quality in addressing swine carcass disposal in our state.
Conclusions
Giving the world the types and quality of foods it wants in the quantities that will be needed an increasing challenge in the 21st century. Meeting this challenge will have to be done without risking environmental damage through inability to properly dispose of, or use, animal by-products. Finding alternatives that fit efficiently into the nutrient cycle as a whole will be critical. Enzyme-processing in combination with mechanical handling as described above removes a potential pollutant while creating a useful nutrient. In addition to spent hens, other areas with great potential are enzymatic digestion and recycling of hatchery waste, swine farrowing waste and normal swine mortality waste. I am currently working with the Nebraska Department of Environmental Quality in addressing swine carcass disposal in our state.
The enzyme digest process is not viewed as a replacement to rendering. However, the two might well complement each other, a common goal – fresh, uncontaminated, recycled, proteinaceous animal by-products producing a species specific, pathogen-free, value-added organic livestock feed ingredient.
Related topics:
Recommend
Comment
Share
Would you like to discuss another topic? Create a new post to engage with experts in the community.
Featured users in Poultry Industry
Shivaram Rao
Pilgrim´s
PhD Director Principal de Nutrición y Servicios Técnicos de Pilgrim’s Pride Corporation
United States
United States
