The availability of winter barley in areas of the U.S. that are not well suited to grow corn, such as the mid-Atlantic states, makes it a feedstock of choice for fuel ethanol production in those regions. Recently, it was found that the Elusieve process, the combination of sieving and air classification (elutriation or aspiration), was effective in fiber separation from corn flour prior to fermentation. The objective of this study was to determine the effect of the Elusieve process on the compositions of fractions from barley flour of a hulled (Thoroughbred) and a hulless (Doyce) barley variety. The barley grains were milled using a hammer mill and sieved into four size fractions. Air classification of the two largest size fractions using a commercial aspirator resulted in heavier fractions with higher starch, higher beta-glucan, and lower neutral detergent fiber (NDF) contents. Hulls were preferentially carried into the lighter fractions, as signified by higher NDF contents of lighter fractions. Elusieve processing was more effective (higher separation factors) for the hulled variety than the hulless variety because higher hull presence caused increased carryover of hull into the lighter fractions for the hulled variety. The increase in beta-glucan and starch contents in barley flour, by hull separation using the combination of sieving and air classification, may increase ethanol productivity and may be beneficial in fuel ethanol production from barley when using a process that converts both starch and beta-glucans into fuel ethanol. Since the Elusieve process was most effective only when hulls were present, any dehulling operation prior to grinding would make Elusieve processing needless.

Fiber separation from these animal feeds could increase the protein and hence increase the value of the animal feed. The objective of the study was to evaluate the combination of sieving and air classification for fiber separation from soybean meal (SBM), cottonseed meal (CSM) and wheat middlings (WM). The effect of yields of lighter fractions on fiber separation from size fractions was also investigated. At low yields of lighter fraction (5%), the quantity of fiber product separated was 3.7, 1.3 and 4.8% by weight of SBM, CSM and WM respectively. At high yields of lighter fractions (15%), the quantity of fiber product separated was 8.9, 3.5 and 11% by weight of SBM, CSM and WM respectively. For CSM and SBM, the enhanced product contained 0.6 to 2.0% higher protein content than unprocessed feed. For WM, the enhanced product contained 0.2 to 0.7% higher protein content than unprocessed feed.ii DEDICATION I would like to dedicate this research to my mother, Ratna mala. Her support throughout the years has enabled me to achieve more than I ever thought possible. I would like to extend this dedication to my father Srinivas and brother Uma Mahesh. INTRODUCTIONThe purpose of this chapter is to give a brief introduction of the current study.Section 1.1 explains the background and significance of fiber separation in protein enrichment of animal feeds. Section 1.2 contains the various methods used in fiber separation and Section 1.3 presents the objectives of this research. Background and significanceThe demand for protein rich plant feeds is rapidly increasing due to the increased concerns in using animal byproducts (meat and bone meal etc) for animal feeds. The digestibility of plant protein is higher in animals compared to the animal derived feeds.Therefore, the use of protein rich plant feeds soybean meal and cottonseed meal increased over the years in North American poultry industry. Poultry industry is the biggest user of soybean meal and in US it consumes approximately 54 percent of all meal produced in the country (1). In the current scenario of increasing demand for protein rich feeds, there is a need to enhance the protein content among these feeds. Soybean meal is a good source of plant protein (48 percent) with high energy and low fiber (1). The advantage of using soybean meal as primary protein source is its consistency in composition with less variation among the meals obtained from different processing plants. Cottonseed meal 2 comes next to soybean meal in terms of the consumption and availability of 41 percent of protein (2). It can be used as animal feed alone or in combination of other feeds to complete the balanced ration. Wheat middlings is another cattle feed with high levels of digestible fiber, low levels of starch and less digestive disturbances which makes it useful feed roughage (3). Methods used for fiber separationSrinivasan et al (2005) separated fiber from distillers dried grains with solubles (DDGS) by elusieve process, the combination of sieving and elutriation, to produce enhanced DDGS...

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