Pasteurized milk in cartons. Tetrahedral cartons made from polyethylene laminated paper board and packed in hexagonal plastic crates have been chosen as the model for analysis of a system of pasteurized milk packaging.
The cartons are produced continuously from a roll of plastic-coated paper which is shaped and sealed into a tube. The tube is filled continuously with pasteurized milk. Transverse seals are made alternately at right angles below milk level so that there is no headspace and the shape of the package is a tetrahedron. The packages are separated by guillotine and placed in hexagonal plastic crates holding 18 cartons each. The crates are stacked on pallets. The crates (and eventually also the pallets) have to be transported from the retail centres back to the milk processing plant. Table 2 gives data on the rolls of laminated paper as used for the system: