Document Type



Virginia Institute of Marine Science

Publication Date



Data report (Virginia Institute of Marine Science) ; no. 40.


Four alternative drying methods for oyster soft tissue were compared: oven drying at 105, 100 and 80°C and freeze drying. Weights were recorded every 12 hours for 5 days, and after sample treatments were switched, every 24 hours for another 3 days. The time required for all of the oysters in a treatment to reach constant weight were 36, 36, 60, and 120 hours for the 105, 100, 80°C ovens and freeze drier respectively. Within a treatment, the time for an individual oyster to reach constant weight was not related to that weight. For oven drying, drying was rapid and complete; there was no additional loss over the remainder of the 120- hour drying period. The average ratio of wet (0-hour) to dry (120-hour) weight were 9.17 to 9.47 for oven drying but only 7.35 for freeze drying. Mter three additional days in 105°C oven, the 105, 100; 80°C oven dried, and freeze dried groups lost an additional less-than-1, 1, 1, and 8% respectively. All oven dried groups gained 1% (over the 5 day) weight in the freeze drier, while the freeze dried group lost an additional 2% in 3 days. It was concluded that the temperature, at least from 80 to 105°C, for oven drying affects final dry weights by 1% or less, but the drying times required for constant weight are different. Freeze drying was less effective than oven drying in removal of water and required more time.