Friday, July 31, 2009

Extrusion of Micro Aquatic and Shrimp Feeds

Joseph Kearns, Aquaculture Process Technology Manager, Wenger Manufacturing, USA

Production methods are reviewed for manufacturing of micro - or what is commonly referred to as starter feeds. Extrusions cooking in various formats are discussed with the technology involved for production of these feeds but also the ability to produce at increased production rate. Typical increase levels are in the three to five times range while allowing all the formulation advantages seen in extrusion of shrimp feeds.

Definitions of Micro feeds
Requirement of Fine Grinding
Review Spherizer Agglomeration System (SAS)
Direct Extrusion Review for Small Diameter Feeds
Dryer Requirements for Micro Feeds
Review of New Technologies for High Capacity Shrimp Feed Production

Thursday, July 30, 2009

The use of rendered animal products in aquaculture diets

Geoff L. Allan, N.S.W. Department of Primary Industries. Port Stephens Fisheries Centre, Nelson Bay, Australia

Aquaculture remains the fastest growing food producing primary industry in the world. Of the approximately 52 million tonnes of production, about 16.3 million tonnes comprises species that are fed. Marine finfish are generally strictly carnivorous and most are fed on fishmeal-based, high protein diets (>45% protein) or even directly fed “trash fish”. Current production of fishmeal is stable, and the increases in demand have been met by diverting fishmeal from other animal feeds. However, future increases in aquaculture production will require alternative protein sources.

Increasing amounts of vegetable proteins are being used but for marine carnivores, a requirement for high dietary protein, driven mainly by an inability to tolerate high dietary carbohydrate, or effectively use either carbohydrate or lipid for energy, has restricted fishmeal replacement to date. However, rendered animal protein sources, such as poultry offal meal, meat and bone meal and blood meal products are excellent protein sources with no carbohydrates and few anti-nutrients. Approximately 12.5 million tones of rendered animal meals are available globally, roughly twice as much fishmeal as is available.

Data for digestibility and utilization of rendered animal products fed to a variety of carnivorous and omnivorous aquaculture species will be presented. Data for trout, red sea bream, tilapia and mud crabs from numerous research studies will be summarized and the potential for use of rendered products discussed. The data demonstrate that rendered animal meals can be excellent protein sources for aquaculture species, including carnivorous marine finfish.

Substantial replacement of fishmeal is possible, particularly with blends of alternative protein sources based on rendered animal meals.

Monday, July 27, 2009

Improving Plant Efficiencies

Galen J. Rokey, Manager, Process Technology, Wenger Mfg., Inc., Kansas, USA

In today’s economic climate, the aquaculture industry is affected by many trends that are affecting plant efficiencies. Industry surveys indicate that energy usage and product safety are the major challenges facing the industry. Sustainability and environmental issues also are impacting aquaculture.

Several specific areas will be reviewed that favorably affect plant efficiency and can easily be implemented.

Trends in aquaculture that impact plant efficiency
A. Raw material costs
B. Market conditions
C. Energy and water conservation
D. Supply chain costs reduction
E. Automation
F. Labor costs
G. Food safety
H. Flexibility
I. Emissions control
J. Lean manufacturing

Specific areas to improve plant efficiency
A. Adjust process to use least cost energy source
B. Tighten product moisture variation off dryer
C. Recycle under-processed material
D. Extended service programs and line audits
E. On-line monitoring and control

Sunday, July 26, 2009

Harvesting the benefits of grain application in Aquafeeds

Dr. Brett Glencross, Stream Leader – Novel Feed Ingredients and Nutrition, CSIRO Marine and Atmospheric Research, Australia

To reduce risk associated with being too dependent on fish meal use in aquaculture feeds, considerable effort has been expended to assess and develop a range of grain protein meals as alternatives. However, the evaluation of such feed ingredients is crucial to their effective application in diets for aquaculture species. In evaluating ingredients for use in aquaculture feeds there are several important knowledge components that should be understood to enable the wise use of any particular ingredient in a feed formulation. The four primary knowledge components are: (1) Ingredient characterization, (2) Ingredient digestibilities, (3) Ingredient palatability, and (4) Nutrient utilization and/or interference of utilization.

In addition to these four key knowledge components, further details on ingredient functionality, gene and/or protein expression, the influence on immune status and organoleptic qualities are also important considerations.

Using this approach a range of feed grain resources have been evaluated in the diets of a range of aquaculture species. While there is no single ideal alternative many of the different feed grain resources offer sound potential when used in the right application. Indeed the judicious use of certain feed grain resources can confer significant nutritional and technical advantages to the feed design and management process.

Friday, July 24, 2009

Aquafeed Trends in South East Asia and China

Urs Wuest, Buhler, Head Engineering & Fulfilment

Changes throughout the entire aquafeed value chain will impact feed millers in the near future and beyond.

Urs Wuest will present the current trends in the aquafeed industry,l including the changes in raw materials, feed manufacturing, aquaculture, processing of the fish and crustaceans and the demand from customers in total and segmented by fish species.He will explain how changing requirements in the aquafeed industry translate into a demand for specific technical requirements, such as extrusion technology.