Individual quick-freezing of moist articles using deep fluidized bed and input conditioner

Claim 2

In I.Q.F. preservation of food and similar articles having surface moisture, the freezing process comprising first subjecting the articles amassed in a first deposit on a foraminous conveyor to flow of gas upwardly through the conveyor and such articles thereon at subfreezing temperature for a selected first time period which takes the articles predominantly to the incipient point of freezing where substantially all of the above-freezing sensible heat is removed without removing the latent heat, with said deposit of articles being in a fluidized state during said first time period, and thereupon subjecting such articles massed in a second deposit, at least a few times deeper than the first deposit, to deep-bed mass fluidization freezing created at least partially by gas at subfreezing temperatures flowed upwardly through the mass for a selected second time period several times longer than the first time period which removes all remaining latent heat from such articles and depresses their temperature materially below freezing throughout.

Claim 3

The process defined in claim 1 wherein the gas flowed upwardly through the amassed articles is circulated repeatedly through such deposits thereof and through gas cooling means operated at substantially the same freezing temperature throughout the process.

Claim 4

The process defined in claim 2 characterized in that the articles are being substantially continuously conveyed throughout the process using separate conveyors for the respective first and second deposits.

Claim 5

The process defined in claim 3 wherein the articles amassed in the first deposit are conveyed at least a few times faster than those amassed in the second deposit.

Claim 6

The process defined in claim 1 characterized in that the articles are being substantially continuously conveyed throughout the process using separate conveyors for the respective first and second deposits.

Claim 7

The process defined in claim 5 wherein the articles amassed in the first deposit are conveyed at least a few times faster than those amassed in the second deposit.

Claim 8

In I.Q.F. processing of food and similar moist articles by deep-bed air-fluidization freezing of the articles amassed together in a deep air-fluidized bed thereof, the preparatory step which conditions the articles relatively quickly against adhering together comprising removing substantially all of the above-freezing sensible heat without removing the latent heat from the articles predominantly by flowing subfreezing air through a mass of the articles in a fluidized state immediately prior to introducing the same into the fluidized bed for deep-bed air-fluidization freezing.

Claim 9

In I.Q.F. processing of food and similar moist articles by deep-bed air-fluidization freezing of the articles amassed together in a deep air-fluidized bed thereof, the preparatory step which conditions the articles relatively quickly against adhering together comprising removing substantially all of the above-freezing sensible heat without removing the latent heat from the articles predominantly by flowing subfreezing air through a mass of the articles in a fluidized state immediately prior to introducing the same into the fluidized bed for deep-bed air-fluidization freezing.

Claim 10

I.Q.F. apparatus for processing food and similar moist articles comprising main deep-bed gas-fluidization freezing means therein operable during a predetermined freezing period to deep freeze the articles amassed together in a deep-bed fluidized state created by air at subfreezing temperature blown upwardly through the mass and further including a freezer conveyor operable to convey the articles from a receiving location to a discharge location during such predetermined freezing period, and article conditioning means including separate, input conveyor means operable during a predetermined conditioning period several times shorter than the freezing period, to deliver articles into said main freezing means at the receiving location, and chilling means operable for reducing the temperature of the articles predominantly to the point (substantially 30° F.) that substantially all sensible above-freezing heat has been removed without removal of the latent heat from the articles by blowing air at subfreezing temperature upwardly through the articles on said input conveyor means during said conditioning period with said articles being in a fluidized state.

Claim 11

I.Q.F. apparatus for processing food and similar moist articles comprising main deep-bed gas-fluidization freezing means therein operable during a predetermined freezing period to deep freeze the articles amassed together in a deep-bed fluidized state created by air at subfreezing temperature blown upwardly through the mass and further including a freezer conveyor operable to convey the articles from a receiving location to a discharge location during such predetermined freezing period, and article conditioning means including separate, input conveyor means operable during a predetermined conditioning period several times shorter than the freezing period, to deliver articles into said main freezing means at the receiving location, and chilling means operable for reducing the temperature of the articles predominantly to the point (substantially 30° F.) that substantially all sensible above-freezing heat has been removed without removal of the latent heat from the articles by blowing air at subfreezing temperature upwardly through the articles on said input conveyor means during said conditioning period with said articles being in a fluidized state.

Claim 12

The apparatus defined in claim 8 wherein said input means is a minor fraction of the length of the freezing conveyor and operable to convey the articles at a speed at least a few times faster than the rate of conveyance thereof on the freezing conveyor and with the air blown upwardly through the articles on the input conveyor means having a velocity creating fluidization of such articles.

Claim 13

The apparatus defined in claim 9 wherein the freezing means and chilling means comprise air refrigerating apparatus incorporating refrigerant evaporation means operable at substantially the same air refrigerating temperature in both the chilling and freezing means.

Claim 14

The apparatus defined in claim 8 wherein the freezing means and chilling means comprise air refrigerating apparatus incorporating refrigerant evaporation means operable at substantially the same air refrigerating temperature in both the chilling and freezing means.