Study on the Storage of Rolled-Compressed Wafers

Drying characteristics and haylaging by hermetic storage

Abstract

In order to store wafers compressed at high moisture content, it is necessary to clear the drying characteristics of wafer in relation to its density and cutting length. Because the rolled compressed wafers whose moisture contents range from 40% to 60% can provide the best moisture content range for haylaging, an experiment regarding haylaging of rolled compressed wafers was carried out, with wafers hermetically stored and packaged in plastic film tubes and obtained the following results.
1) The relation of moisture content to drying time for wafer density and cutting length gave a straight line when it was plotted on semilogarithmic paper. Some differences of drying rate in the results arised from wafer density and cutting length, but the drying rate was very slow.
2) The difference in moisture distribution of dried wafers was larger along the axial direction than along the radial direction, and the moisture contents of dried wafers decreased roughly along the radial direction and straightly along the axial direction.
3) The expansion of plastic film tubes by water-vapor and CO₂ generated from the hermetic storage wafers arised at the moisture content above 49%, and not under 43% regardless of wafer density and exhaust of air from packaged wafers.
4) The generation of mold during hermetic storage depended on the physical properties of plastic films. The plastic films are to have air tightness and resistance to mechanical shocks during transportation and handling.
5) The lactic acid fermentation during hermetic storage occurred vigorously with the increase of wafer density and moisture content of wafers, but the estimates as a haylage took the best rank regardless of the quantity of fermented lactic acid. By this method, wafers could be stored for about a year or so.
6) The changes in nutritive values during hermetic storage were influenced significantly by moisture content when it was packaged, and not very much by wafer density. Changes in crude protain were very small, and crude ash, crude fiber and crude fat increased a little whereas NFE, carbohydrates and organic matters decreased a little.