Alternate vacuum freeze and heat dehydration of food products

Claim 1

IN A PROCESS FOR THE DEHYDRATION OF A FOOD PRODUCT THE STEPS OF SUBJECTING SAID PRODUCT TO VACUUM IN A VACUUM ZONE, SAID VACUUM BEING OF THE ORDER OF AT LEAST ABOUT 4.6 MM. OF MERCURY WHEREBY THE PRODUCT IS PARTIALLY DEHYDRATED AND COOLED TO JUST ABLVE THE FREEZE POINT THEREOF DUE TO SUBSTANTIAL EXTRACTION OF THE HEAT OF VAPORIZATION THEREOF, MAINTAINING SAID ORDER OF VACUUM FOR THAT PERIOD OF TIME SUFFICIENT TO REMOVE FROM ABOUT 3% TO ABOUT 10% OF THE ORIGINAL MOISTURE CONTENT FROM SAID PRODUCT, SUBJECTING SAID PRODUCT TO A VACUUM OF ABOUT .2 MM. TO 5 MM. OF MERCURY WHEREBY SAID PRODUCT IS DEHYDRATED FURTHER AND THE TEMPERATURE THEREOF LOWERED TO BELOW FREEZING DUE TO SUBSTANTIAL EXTRACTION OF THE HEAT OF FUSION THEREOF, SAID VACUUM TREATMENT STEPS CREATING OPEN PASSAGEWAYS IN SAID PRODUCT, REMOVING SAID PRODUCT FROM SAID VACUUM ZONE, SUBJECTING SAID PRODUCT EXTERIORLY OF SAID ZONE TO AIR DEHYDRATION AT ELEVATED TEMPERATURE TO CAUSE FURTHER DEHYRATION THEREOF BY MOISTURE ESCAPEMENT THROUGH SAID PASSAGEWAYS, RETURNING SAID PRODUCT TO SAID VACUUM ZONE FOR FURTHER DEHYDRATION THEREOF, AND RESUBJECTING SAID PRODUCT TO SAID ABOUT .2 MM. TO ABOUT 5 MM. OF MERCURY TO FINALLY FREEZE SAID PRODUCT.