Design and Testing of an Automated Ohmic Thawing Device for Shrimp

摘要

The purpose of this study was to design, build and test an automated, computer controlled prototype ohmic thawing unit to thaw frozen food blocks. Runaway heating was prevented by controlling surface temperature of blocks with thermistors. Control ofcurrent to electrode quadrants was achieved by distributed control circuitry custom designed and built. Voltage was adjusted automatically to maintain constant current through the block. Moisture content of large shrimp was not different when ohmicallyor conventionally thawed. Small shrimp had higher moisture content when conventionally thawed. Microbial levels were not significantly different. Sensory attributes showed that panelists could not differentiate between conventionally and ohmically thawedshrimp.