Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/2/2009
Publication Date: 6/2/2009
Citation: Hojillaevangelist, M.P. 2009. UTILIZING CORN GERM MEAL IN PLYWOOD GLUE. Meeting Abstract.
Technical Abstract: This study was conducted to evaluate the potential of corn germ meal as protein extender in plywood adhesive. This research is part of our laboratory’s efforts to develop new uses for the proteinaceous co-products from cereal and soybean processing. We were previously successful in formulating a soy flour-based plywood glue applied by foam extrusion that is now used commercially. For corn germ meal, however, we selected plywood glue intended for sprayline application as the media for testing its performance as extender. This type of glue does not require foaming and is more tolerant of non-protein components of the extender (e.g. oil) than glues for foam extrusion. Partially defatted dried corn germ, containing 2.1% (db) crude oil and 24.7% (db) crude protein, was ground in a coffee mill until a 40-mesh particle size was obtained. The corn germ meal was then substituted (on protein basis) for wheat flour, industry’s current protein extender, in the standard glue mix for sprayline glue. Duplicates were made for each glue mix. Glues were applied by a roll coater onto 12 in x 12 in (30.5 cm x 30.5 cm) Southern pine veneers. Three-ply wood panels were made by hot-pressing assembled veneers for 3 min at 325°F and 250 psi. Two panels were made for each glue mix replicate. Panels were then cut into 1” W x 3 1/8” L (2.5 cm x 8 cm) test specimens. Wet tensile strengths of plywood test specimens were determined by using a plywood testing machine (Globe Machine Manufacturing Co., Tacoma, WA). Glues were considered strong if their wet tensile strength values were at least 200 psi. The glue containing corn germ meal showed satisfactory mixing performance and had a final viscosity that was almost identical to that of the standard (wheat flour-based) glue (24, 000 cp vs. 23,340 cp, respectively). The mean tensile strength of the corn germ-based glue (195 psi) was likewise close to that obtained for the standard glue (213 psi). These results indicated that corn germ meal has strong potential to be an alternative protein extender in plywood glues for sprayline coater.