Extrusion workshop: Practical extrusion and diet development for extrusion processing

Peter Hutchinson, Director, E.N. Hutchinson, Auckland, New Zealand

The workshop will comprise two sessions: Practical Extrusion and Diet Development for Extrusion Processing. Practical Extrusion will focus on feed extrusion principals such as screw designs and profiles; die design, extruder trouble shooting, drying and cooling. The session on practical nutrition will look at diet development for extrusion processing and cover such topics as sourcing locally available material, matching extruder profile to formulation, die design in relation to species, high retention (water stable) diets, optimizing the pellet through extruder settings (cook, minimizing nutritional damage, stability and density), basic quality control, post coating and density control through coating and dryer design. Practical problem solving is at the heart of the workshop and Peter will be joined by an international panel of extrusion experts to answer your extrusion questions.

Use of distiller’s dried grains with solubles in tilapia diets

Chhorn Lim, Supervisory Nutrition Scientist, Aquatic Animal Health Research Unit, USDA, ARS, Auburn, USA

Distiller’s dried grains with solubles (DDGS) are currently readily available and less expensive than other conventional protein sources. However, its nutrient content and nutritional value vary with the source and quality of grain, fermentation and drying processes and the quantity of distiller’s solubles added. Generally, corn and wheat DDGS are deficient in lysine and methionine for tilapia, with lysine being the most limiting. Feeding studies showed that 20 - 30% corn or wheat DDGS can be included in tilapia diets without requiring lysine supplementation. With lysine supplementation, DDGS at levels of 40% or higher can be used without affecting growth and feed efficiency. DDGS also contain yeast, a rich source of beta glucan and nucleotides that have been reported to enhance immunity and disease resistance in fish. Corn DDGS, due to its high oil content that is rich in linoleic acid, is an excellent source of energy and essential fatty acid for tilapia. High concentrations of xanthophylls in corn DDGS may impart yellow pigment in fish flesh if included at high levels. Considering various factors affecting the nutritional value and quality of pellet and fish product, 15 - 20% DDGS appears to be optimum in diets of tilapia.

The missing link for fish meal substitution: low-cost, high-volume, sustainable protein and EPA-rich microalgae (spirulina) biomass

Miguel Cizin, President, Biomat

The debate over sustainability of fish feed ingredients such as fish meal, which is mostly sourced from unsustainable pelagic fish wild catch,  has promoted the development of sustainable vegetable-sourced protein alternatives as a viable substitute.  In addition to other aquatic and non-aquatic ingredients, such as soy, microalgae biomass in general, and spirulina algae in particular, has been identified and acknowledged as the most promising ingredient for high-volume, sustainable protein, due to its unique ability to capture CO2 and available energy and very efficiently convert both into protein and nutrient-rich (EPA) biomass.  There is a long-standing and still very strong global consensus that the single missing link for algae to fulfill its promise as the optimal ingredient to substitute a high percent of fish meal in animal feed is the availability of scalable, competitively priced algae biomass produced in a sustainable process, using a limited amount of non-fertile land, water, nutrients, and energy. A new, patent-pending, sustainable algae biomass production technology is described, which can be deployed on non-fertile land, and which does not require a nearby smokestack as it captures the large amount of carbon molecules required directly from the available CO2 in the surrounding atmosphere.  Typical production volumes per unit surface and overall production costs per ton of algae biomass produced in the first facility deployed in Israel will be presented.

Total replacement of fish meal by poultry by-product meal in shrimp feeds

Victor Suresh¹ & Sergio Nates²

¹ Integrated Aquaculture International, Brunei Darussalam

² Fats & Proteins Research Foundation, USA

The presentation will highlight efforts to completely replace fishmeal in shrimp feeds using poultry byproduct meal (PBM). In formulas that are similar to commercial feed formulas and containing 21-24% premium fishmeal, total replacement by PBM results in shrimp performance that is lower by about 15%. We have investigated the attractability and palatability factors in PBM, and found them to be present in significant quantities. Nutritive value of PBM’s fat component for shrimp has also been extensively investigated. The results of the investigations will be discussed in the presentation.       

New Non-GMO High Protein Soybean Meals without Anti-Nutritionals for Aquafeeds

Alejandro Buentello, VP of Research and Aquaculture Business, Schillinger Genetics, Inc.

Soybean cultivars have been selected with 15-20% higher protein content and with the difficult-to-digest carbohydrates raffinose and stachyose, as well as trypsin inhibitors significantly reduced. The defatted meal derived from these cultivars exceeds 56% in protein content and with further gentle processing will surpass 60% in crude protein (CP). Feeding trials comparing protein digestibility, metabolizable energy, mortality, FCR and growth performance have been conducted with Atlantic salmon, rainbow trout, Pacific white shrimp, European sea bass, cobia, yellowtail and red drum. Additional trials with other aquaculture species will be conducted in 2012. The search has been intensified for new soy meals and traits that will further improve the nutritive value of aquafeeds in key aquatic species. In order to expand testing efforts on aquafeeds, Schillinger Genetics (SG) has conducted replicated feeding trials utilizing “first feeding” rainbow trout fry with an average initial weight of ~ 0.1 g. Experimental diets were formulated to contain 42% CP, 15% lipid and derive the dietary protein from sardine meal (reference diet), sardine meal plus SG-cultivar 3010 (50:50) or sardine meal plus soy protein concentrate (SPC) obtained from regular commodity soybeans (also 50:50 replacement). The feeding trial was conducted over a 6-week period to allow for adequate treatment separation. Results on growth  and survival indicate that SG-3010, substituting half of the fishmeal is able to support the same growth performance as the fishmeal-based diet and a significantly higher weight gain than the SPC diet. Taken together, these results indicate that the use of SG-3010 allows for a higher fishmeal replacement level in rainbow trout diets. In addition, due to its higher protein density, lesser amounts of SG-3010 are required to meet the dietary requirement for this species. Therefore, the nutritional value of SG-3010 is significantly higher than that of SPC obtained  from conventional commodity soybeans.

Reducing feed cost in aquaculture by optimizing nutrient utilization and gut health

Peter Coutteau, Business Development Manager – Aquaculture, Nutriad International NV, Belgium

As ingredient prices rise, nutritionists search for new options for cost reduction by maximizing the efficiency of digestive and metabolic processes which are at the basis of converting nutrients into meat gain. The presentation illustrates the potential to reducing cost of feeding in aquaculture by improving the efficiency of nutrient utilization and optimizing gut health. Digestibility enhancing additives have the potential to improve nutrient utilization from cheap ingredients and stimulate the conversion of nutrients into meat gain and less into fat accumulation in muscle and viscera. The potential of species-specific digestibility enhancers, tailored to the digestive physiology and feed formulation of each aquaculture species, is illustrated with results from feeding trials with Tilapia (Oreochromus niloticus),  tra catfish (Pangasius hypophthalmus),European seabass (Dicentrarchus labrax), and white shrimp (Litopenaeus vannamei).  Fish and shrimp are highly exposed to exchanges of microflora between the environment and the digestive system. Furthermore, the digestive system of fish and shrimp is the main entry port for bacterial and viral infections. Synergistic blends of natural compounds (“phytobiotics”) are capable of modulating the microflora towards a favorable composition, favoring the development of beneficial bacteria and inhibiting potentially pathogenic micro-organisms. The efficacy of phytobiotics was tested under lab and field conditions for fish and shrimp production, resulting in significant improvements in survival, growth and food conversion. 

A review of amino acids levels in fishmeal in Southeast Asia

Dhanapong Sangsue, Evonik Degussa (SEA) Pte. Ltd. Technical Sales Manager

Animal protein sources, such as fishmeal, have typically been used in aquatic animal feed to provide essential amino acids and other nutrients, but the nutritional value of these protein sources can vary greatly due to type of species used and processing conditions. Considering the importance of fishmeal in aquatic feeds, it is important to understand this nutrient variation and its impact on production performance if not accounted for. In 2010, 266, 387, 241, 209, and 39 samples of locally-produced fishmeal from Vietnam, Thailand, Philippines, Indonesia, and Malaysia, respectively, were analyzed for the crude protein and amino acid contents. The analyzed crude protein contents of those fishmeal samples ranged from 56.23 to 63.18 %, while methionine contents ranged from 1.34 to 1.75%, and lysine contents ranged from 3.61 to 4.71%. Fishmeal from Indonesia had the highest levels of CP, Met and Lys with 63.18, 1.75, and 4.18%, respectively, whereas fishmeal from Vietnam had the lowest with 56.23, 1.34, and 3.61%, respectively. Fishmeal produced in Thailand had the greatest variation with a coefficient of variation of 9.23% for CP, while Philippines had the most-consistent production with a coefficient of variation of 4.59%. A portion of the variation can be explained by origin of fishmeal and processing. For example, analyses of 87 Tra catfish fishmeal samples from Vietnam (by-products from Pangasius processing) revealed 58.5%, 4.04%, 1.48% of average CP, Met and Lys respectively with coefficients of variation of 6.0%, 12.3%, and 14.2%, respectively. To formulate diets as precisely as possible, it is critical to both understand the amino acid requirements of the aqua species being fed and to understand the nutrient variation in the ingredients that will be used to produce that diet. Without this knowledge, safety margins must be increased, which increase diet cost due to less efficient use of this costly raw material. These data highlight the importance of analyzing fishmeal on a routine basis in order to better understand its nutrient content and the variation contained therein.

Current Aquafeed and Aquaculture in Thailand

Dr. Juadee Pongmaneerat, Senior Expert in Fishery Product and Inspection, Thai Department of Fisheries, Bangkok, Thailand

Thailand is a leading country in aquaculture and aquatic feed development. The country boasts 64 feedmills and premix plants for aquafeed, of which 10 are GMP standard and six HACCP certified. The Department of Fisheries (DoF) has developed policies for food safety standards and promotes the CoC and GAP for aquaculture farms, and GMP and HACCP standards for feed manufacturing, over and above basic feed safety and quality control regulations.
In 2009 some 1.25 million tonnes of aquafeeds were consumed: 672,000 tonnes shrimp feed and 581,800 tonnes fish feed.

The status of economic aquatic species such as marine shrimp, giant fresh water prawn and tilapia will be presented. The DoF regulatory framework for quality control, the inspection and certification system for feed manufacturing and fishery products processing plants will also be discussed.

Increasing the ingredient flexibility of floating feeds

William Henry, Director of Technology and Research & Development, Extru-Tech, USA

The environment in which aquatic feeds being produced in Asia today has changed dramatically from even a few years ago. Now, more than ever, the ‘efficiency’ of production is critiqued at the same levels as ‘quality’ and ‘quantity’ of production.

This presentation will focus on the greatest input cost to most aquatic feed production process’s, and that is raw materials.

When reviewing the ‘Total Cost of Production’ for a specific type of feed, the raw material cost is typically in the range of 80 to 90%. Needless to say, a 10% savings on the raw materials will have a greater impact on production cost efficiency than most likely anywhere else in the process.

This strategy of increasing the process’ ingredient flexibility will be addressed from two primary angles. We will first discuss changes and enhancements in the core pieces of equipment in a typical extrusion process. And secondly, a review of proper/recommended process management directives will be presented.

Reassuring the value-chain as to the sustainability and purity of fishmeal and fish oil

Dr. Andrew Jackson, Technical Director, International Fishmeal and Fish Oil Organisation, U.K.

Two of the most important issues facing the fishmeal and fish oil industry in recent years has been the question of the sustainability of the fisheries providing the raw material and the purity of the products arriving at the feed mills. The industry is therefore looking at ways of reassuring the value-chain on these two critical issues. The best way to do this is using third-party audited schemes and the alternative schemes both developed and in the process of development will be discussed.

One scheme that is being initiated to address both these issues is the new IFFO Global Responsible Supply Standard. The development of this scheme will be discussed and how it assesses both fisheries and factories to provide the reassurance required.

Stabilizing formulation cost and performance of aquafeeds requires innovative approaches

Dr. Peter Coutteau, Business Development Manager Aquaculture, INVE Nutri-Ad, Belegium

In the livestock industry, a wide variety of feed additives are currently being investigated to improve cost-efficiency of animal nutrition. Organic acids, enzymes, probiotics, prebiotics, highly available minerals, essential oils and natural plant extracts are some alternatives to antibiotics without causing bacterial resistance that would have at least similar effects on growth and food conversion.

This active search for natural growth promoters is starting to extend into fish farming as consumer pressure is likely to ban antibiotics from production in most countries. Although the screening of these compounds for aquaculture has just started, promising results have been obtained with different species.

The presentation illustrates the development of a number of innovative feed additives to optimize the utilization efficiency of nutrients from traditional ingredients for aquaculture species

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

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.

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

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.

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.

Technical Advancements in Extruded Shrimp Feeds

Wenger Mfg., Inc., Kansas, USA
Email: jkearns@wenger.com

This presentation will cover the current possible technology used in production of shrimp feeds via extrusion and the advantages of this method of production.

The review will cover all aspects of this process from the raw materials through to drying and cooling before packaging.

The final product quality aspects of shrimp feeds via extrusion compared to other processing methods will also be presented.

Starter Aqua Feed Technology

Will Henry, Extru-Tech, Inc., Kansas, USA
Email: extru-techinc@extru-techinc.com

a. Size Comparison
b. Poor Pellet Construction
c. Preferred Pellet Construction

2. Mixing Considerations
a. Dedication
b. Grinding/Pulverising
c. Sifitng (Pre & Post Production)

3. Starter Diet Production
a. Pellet & Crumble
1. Overview
2. Pros and Cons
b. Direct Extrusion
1. Overview
2. Pros and Cons
c. Spheronise & Agglomerate
1. Overview
2. Pros and Cons

4. Vitamin Survival
a. Vitamin Uses
b. Vitamin Survival
c. Comparison

5. Flexibility

6. Research Results
a. FCR
b. Uniformity
c. Water Quality / Waste Management
d. Survival Rates

7. Q&A

Ingredient Trends and the Effects on the Extrusion Process

Galen J. Rokey, Manager, Wenger Mfg., Inc., Kansas, USA
Email: grokey@wenger.com
I. Benefits of proper particle size in raw materials
a. Product appearance
b. Reduction of blocked die orifice
c. Ease of cooking
d. Increase in throughputs

II. Protein constituents in recipe
a. Functional versus non-functional sources
b. Impact of high levels of vegetable proteins

III. Starch components of the recipe
a. Starch functionality
b. Recommended starch levels

IV. Effects of fat in the diet
a. Internal versus external fat addition
b. Impact of fat levels on the product technical properties
c. Proper analysis methods for fat levels

V. Role of minor ingredients
a. Vitamins and pigments
b. Humectants and other preservatives
c. Rework

Beyond Pre-Conditioning – Reducing Carbon Footprint and Increasing Quality

Colin Mair, Cormal Technology Ltd., U.K.
Email : colinmair@btinternet.com

The presentation will be on upstream processing to improve process efficiencies.

It will explore work done on early pre-hydration and the effect on improved production rates, the hydration being either/and combinations of grain tempering and last minute addition of water to ground powders before going into the storage bin that feeds the extruder.

Also there will be discussion of high speed continuous mixer/choppers to hydrate and add other liquids before the conditioner, and the theory that supports these technologies.

Also ways of misting steam and water into existing conditioners and the beneficial effect of these. Also the effect of pre-heating conditioning water.

The presentation will be an overview of techniques that are available to improve product quality through homogenous mixing and heating and to improve production rates and reduce machine wear.