E. R. Skoch’s research while affiliated with Kansas State University and other places

Summary The effects of a steam-pelleted corn-soybean meal diet on the performance of 146 pigs were examined. Pelleting variables were closely monitored during processing. Treatments in- cluded (1) mash, (2) mash with 2.5% molasses replacing corn, (3) dry-pelleted mash, (4) steam-petleted mash and (5) mash with 2.5% liquified corn. Growth and digestibility trials were conducted with weanling (8.5 kg) and grower-finisher (48.0 kg) pigs. Steam condition- ing before pelleting made pellets more durable and resulted in less starch damage and less consumption of electrical energy than did dry pelleting. Steam acted as a lubricant between the mash and die hole surface. More than 70% of the energy required for steam pelleting was used to generate steam. None of the processing methods studied improved (P

Summary One hundred and fourteen pigs were used to study a steam-pelleted and extrusion-cooked diet containing 15% wheat middlings. Pellet- ing variables were closely monitored during processing. Treatments included (1) mash, (2) dry-pelleted mash, (3) steam-pelleted mash and (4) corn and wheat middlings extruded before steam pelleting. Growth and digestibility trials were conducted with weanling (15.5 kg) and grower-finisher (46 kg) pigs and a preference trial was conducted with 27.9-kg pigs. Steam conditioning before pelleting resulted in more durable pellets, less starch damage and reduced consumption of electrical energy compared with dry pelleting. More total energy was required to steam pellet than to dry pellet when energy required to generate steam was con- sidered. Pellet production rate was increased by steam conditioning of the mash before pelleting. More than 70% of the energy required for steam pelleting was used to generate steam. The extrusion process resulted in extensive gelatinization of corn and wheat middling starch granules. All processing methods im- proved (P

A poultry layer-diet was used in experiments to determine the effects of steam-conditioning level on pelleting variables. Dry pelleting was compared with steam conditioning (to 65 and 80° C) before pelleting, at both constant and maximum production rates. Samples were obtained before and after conditioning, and after pelleting. Electrical energy used by the pellet mill was measured with a watt-hour meter, and the amount of steam used for conditioning was calculated using steam tables. Temperature rise of the meal being extruded through the die and electrical energy required to pellet showed that steam decreased mechanical friction during pelleting. Pellet durability and percentage of fines from the scalper showed that steam improved pellet quality. Pressing the mash through the pellet die caused more starch damage during dry pelleting than during steam pelleting. Starch was not damaged during the steam-conditioning process. Total energy required for pelleting (electrical plus steam) was highest for the 80° C treatment. However, steam conditioning allows increased production rates and improved pellet durability during handling and transportation of finished feeds.

One hundred forty-six pigs were used to study the effects of steam pelleting a corn-soybean meal diet on pig performance. Treatments included ground meal, meal steam conditioned to 80 C (176 ̊F) before pelleting, meal pelleted without steam conditioning, and a meal diet with 2% molasses replacing corn. Steam-conditioning the meal before pelleting resulted in less starch damage, and less electrical energy was required for pelleting. Pellet durability was considerably increased with steam conditioning. None of the processing methods studied caused significant (P<.05) improvement in daily gain, feed efficiency, or energy digestibility for weanling pigs. A significant improvement (P<.05) over the control diet in feed efficiency and energy digestibility, was found with either pelleting treatment for grower-finisher pigs. However, daily gain was not significantly (P<.05) improved. Swine Day, Manhattan, KS, November 9, 1978

One hundred forty, three-week old weanling pigs were used to evaluate the effects of feeding a heat-processed, predigested liquid diet. In Trial I, pigs were randomly allotted to a dry crumbled diet or a processed liquid diet. The basal corn-soybean meal diet contained 20% protein. A preference trial and a digestion trial were also conducted using the same treatments. A second feeding trial was conducted using a basal diet which contained 30% whey. Treatments consisted of a dry meal diet, a dry meal + water diet, and a processed liquid diet. Swine Day, Manhattan, KS, November 9, 1978

Hydrothermally processed starch urea mixtures employed in urea-containing liquid supplements were shown to improve N use through in vitro rumen fermentation. Starch sources used were potatoes and corn. The starch source was blended with feed-grade urea (45% N) and water in a specific starch source-urea ratio, then hydrothermally processed. HâPOâ and EtCOâH were added to lower pH and to act as an antifungal agent, respectively. In vitro microbial protein synthesis showed the 1.63:1 potato-based supplement on an as-is basis had more protein synthesized than did either the 1.90:1 potato- or 1.83:1 corn-based liquid supplement. However, on a dry basis, the corn-based supplement had more protein synthesized than either of the potato-based supplements. Compared with a 1.83:1 corn-based supplement, a 1.83:1 potato product performed equally well or better, based on microbial protein synthesized.