Single Screw Extrusion Processing of Soy White Flakes Based Catla Feed

An initial investigation into the inclusion of soy white flakes (SWF) and high protein distillers dried grains (HP-DDG) in catla (Catla catla) diet, belonging to the family Cyprinidae, was conducted using a single screw extruder. Three isocaloric (302 kcal/100 g) ingredient blends containing graded levels of SWF in combination with HP-DDG and other required ingredients were formulated to contain a net protein content of 31.5% (wet basis). Extrusion processing was then performed using three levels each of SWF content, moisture content, and temperature gradient keeping a constant screw speed and die diameter. Effects of these variables on extrudate physical properties including: color, pellet durability index, bulk density, water absorption index, water solubility index, unit density and expansion ratio were extensively analyzed. Increasing the level of SWF resulted in increase in water absorption index and unit density but decrease in expansion ratio. The interaction effect of SWF content, moisture content and temperature were significant for color, pellet durability index, bulk density and expansion ratio. All the extrudates showed relatively high pellet durability and inclusion of SWF produced less expanded and more compact textured extrudates

Effect of Different Extrusion Processing Parameters on Physical Properties of Soy White Flakes and High Protein Distillers Dried Grains-Based Extruded Aquafeeds

Nutritionally balanced ingredient blends for catla (Catla catla), belonging to the family Cyprinidae, were extruded using single screw extruder. The extrusion was carried out at five levels of soy white flakes content (21%, 29%, 40%, 52%, and 59% db), five levels of moisture content (15, 19, 25, 31, and 35% db) and five levels of barrel temperature (100, 110, 125, 140, and 150 ºC) using three different die nozzles (having L/D ratios 3.33, 5.83, and 7.25). Blends with net protein content of 32.5% contains soy white flakes, along with high protein distillers dried grains (HP-DDG), corn flour, corn gluten meal, fish meal, vitamin, and mineral mix. A central composite rotatable design (CCRD) and response surface methodology (RSM) was used to investigate the significance of independent and interaction effects of the extrusion process variables on the extrudates physical properties namely pellet durability index, bulk density, water absorption and solubility indices and expansion ratio. Quadratic polynomial regression equations were developed to correlate the product responses and process variables as well as to obtain the response surfaces plots. The independent variables had significant (P \u3c 0.05) effects on physical properties of extrudates: (i) higher soy white flakes content increased the pellet durability index and water absorption index, but decreased the water solubility index, (ii) higher temperature decreased pellet durability index, bulk density and water solubility index, (iii) increased L/D ratio from 3.33 to 7.25 increased the pellet durability index, expansion ratio but decreased the bulk density of the extrudates

Techno-Economic Modeling of Coproduct Processing in a Corn Based Ethanol Plant in 2012

Coproducts, such as Distillers Dried Grains with Solubles (DDGS), produced during ethanol production are essential to the economic sustainability of each ethanol plant as they provide an additional source of revenue. DDGS is extensively used as animal feed, but has a relatively low market value compared to the biofuel. By fractioning DDGS into lighter and heavier fractions, the overall composition changes potentially increasing the value of the coproducts as they become more desirable to different markets. Earlier studies have examined fractionating DDGS using sieves and aspirators. This project examined the techno-economics of adding fractionation systems onto an existing 40 million gal/y ethanol plant. The model allowed for estimations of fixed capital costs, annual operating costs, annual revenues, and net profits, in order to determine the economic feasibility of adding three different fractionation systems. The first fractionation system consisted of a single sieve, and the retained material was passed through an aspirator. The second system was similar to the first but with a second sieve and aspirator. The third system added a third set of them. In addition to utilizing different fractionation systems, the scenarios examined the effects extracting corn oil and producing DWG in addition to DDGS. The fractionation systems examined in this study increased the capital costs associated with the facility, but did not greatly affect the overall annual operating costs. The net profits in the four most profitable scenarios were $0.349/gal EtOH/y (scenario 14),$0.350/gal EtOH/y (scenarios 6 and 10), and $0.351/gal EtOH/y (scenario 2)

Modeling Single-Screw Extrusion Processing Parameters and Resulting Extrudate Properties of DDGS-Based Nile Tilapia (Oreochromis niloticus) Feeds

A single-screw laboratory extruder was used to conduct an L18 (22´ 36) Taguchi fractional factorial study of aquafeed processing. The ingredients were based on a formulation for nutritionally-balanced Nile tilapia diets containing distillers dried grains with solubles (DDGS) and soybean meal as the main protein sources, in addition to constant amounts of corn flour, whey, and fishmeal. The effects of three levels of DDGS (20, 30 and 40%), soybean meal (30, 40 and 50%), ingredient moisture content (20, 30 and 40% db), screw speed (100, 150 and 200 rpm), die dimension (L/D ratios of 5, 9 and 13), barrel temperature (80-100-100°C, 80-120-120°C and 80-140-140°C) and two levels of screw configuration (compression ratios of 2:1 and 3:1) on extrudate physical properties (moisture content, water activity, bulk density, unit density, expansion ratio, pellet durability index, water absorption and solubility indices, water stability, color) and extruder processing parameters (resulting temperatures, die pressure, extruder torque, mass flow rate, apparent viscosity, and specific mechanical energy) were determined. Data from raw materials, processing conditions, and extrudate properties were used to develop surface response curves and equations. However, predominantly low R2values (\u3c 0.5) only permitted linear relationships between some independent parameters and response variables. Regarding main effects, die pressure significantly decreased with higher DDGS levels, moisture content, temperature, lower die L/D, and higher screw compression. Expansion ratio decreased significantly with higher moisture content and lower die L/D. Significant differences in color were caused by changes in DDGS levels and moisture content. In summary, DDGS, moisture content, die dimension, and extrusion conditions had the biggest impact on most of the extrudate physical properties and processing conditions. Different combinations of these independent factors can be used to achieve desired extrudate physical properties and processing conditions