Food or edible material: processes – compositions – and products – Contacting food in liquid or solid state with exteriorly... – Applied material formed by combustion or is product of...
Reexamination Certificate
2002-03-01
2004-03-30
Yeung, George C. (Department: 1761)
Food or edible material: processes, compositions, and products
Contacting food in liquid or solid state with exteriorly...
Applied material formed by combustion or is product of...
C034S207000, C099S355000, C099S386000, C099S44300R, C099S479000, C126S02100R, C126S02100R, C426S465000, C426S521000, C426S524000, C432S133000
Reexamination Certificate
active
06713107
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to forced airflow systems for food treatment facilities such as vertical rise dryers, smokers, curing chambers, ovens or warmers, coolers, and/or freezers.
BACKGROUND OF THE INVENTION
Conventionally, several different food treatment system configurations have been used to smoke, cure, dry, cook, cool, or freeze food products such as meat products so as to increase production capacity while attempting to limit the floor space required for carrying out same. In so doing, vertical rise systems have been used with spiral conveyors to move food vertically through the oven while exposing the food to certain processing conditions as it moves from top to bottom or bottom to top. Other systems employ tunnel or linear floor mounted systems that direct food through on trolleys or the like.
Examples of vertical systems include the Northfield LST (Large Spiral Technology) freezer available from Frigoscandia Equipment (fmcfoodtech.com) is a high capacity non-self stacking spiral freezer that employs spiral conveyors with belts available in different widths. Ryson International Inc. of Newport News, Va., provides spiral conveyors that are purported to feature a small footprint and space savings over other brands with load capacities of up to 200 fpm. Another example is the TURBO-Dryer® from Wyssmont (wyssmont.com). The TURBO-Dryer® uses a stack of slowly rotating circular trays. In operation, food is fed onto the top tray and, after one revolution, is wiped onto the next lower tray where the operation is repeated. The trays are enclosed in a vertical enclosure that circulates heated air or gas about the food on the trays. Each level in the enclosure may be held at a uniform temperature or the enclosure may be configured with zoned temperature regions having different temperatures. Yet another example is found in U.S. Pat. No. 5,942,265 that describes conveying pepperoni meat to a conventional spiral dryer that includes a number of tiers (typically about 38-42) according to the initial moisture level, the desired final moisture level, the relative humidity of the air, the total amount of water to be removed, the temperature, and the conveyor speed.
An example of a tunnel-like system, available from ALKAR located in Lodi, Wis., employs a plurality of serially connected in-line rooms or chambers with sidewalls and front and rear doors on opposing sides of the rooms that cooperably open and close to hold the food enclosed within each room for predetermined intervals of time as the food progresses forward on the trolleys through the series of rooms forming the tunnel. The walls may include a series of downwardly extending baffles that are aligned with baffles on the opposite wall.
The food is positioned on a trolley that is automatically moved serially horizontally forward through the tunnel and stopped in each chamber for a period of time so that the food on the trolley is exposed to the environmental conditions in the enclosed chamber. The trolley may include multiple batches, trays, or tiers of stacked food items. In operation, the trolley is suspended from rails and enters the open doors of one chamber and the front and rear doors of the chamber close with the trolley stopped therein, thereby defining a closed chamber. One or more trolleys rests in the closed chamber for a period of time during which the chamber is brought to its desired temperature and food can be exposed to heated air-flow. Subsequently, doors on the opposing side of the chamber open, and the trolley then re-initiates movement to pass through the open doorway and enter the next in the serial line of chambers or rooms. Each chamber or room may generate a different environmental condition. The trolley may be connected to a series of trolleys that move in unison through the various chambers.
When processing food through the various systems, the distribution of air or airflow about the food may influence the manner in which the food is cooked, cooled, or otherwise thermally and/or environmentally processed. Uneven distribution patterns may yield a non-uniformly processed product batch. This can be particularly problematic in large capacity continuous process ovens. Other airflow or air distribution patterns may increase the time it takes to reach the desired environmental condition or temperature and may be inefficient in its use of energy.
For example, in general, in the tunnel system, heated air may be directed to flow down from nozzles positioned on the ceiling, discharged at various vertical heights through baffles along one sidewall, and then collected to travel back up to exit in the opposing sidewall of the chamber or at a centrally located exit-air return, that may also be located about the top portion of the chamber. This airflow pattern forces air down about the food on the static trolley, the air rebounds off the walls and floor (and/or trolleys, trays, and screens) and travels back up through the food on the trolley to exit in the air-return. The airflow may be characterized as substantially laminar, potentially inhibiting uniform heat transfer and/or air distribution about the product on the trolley or trolleys. Unfortunately, fresh air may be unevenly distributed in the chamber; the product in the chamber may be non-uniformly exposed potentially leaving dead-spots and/or irregular degrees of exposure to heat and or moisture. This may yield a thermally inconsistent product at various locations thereof so that portions of the product may be overdone, underdone and/or inconsistently processed.
For continuously or substantially continuously moving product lines that move during the thermal treatment itself (such as those employing moving or conveying floors), uniform air distribution may also be problematic in that the moving floors may create physical or air wall blockage or turbulence that can also inhibit the uniform exposure or create undesirable temperature gradients in the system (such as an oven). For example, in round and/or vertical stacked tier ovens or systems that employ substantially circularly configured moving floors, a centrifugal force may be generated that may undesirably force the heated or desired environmental air to the outermost wall of the oven causing a potential large and inefficient temperature gradient at certain zones or regions in one or more tiers or levels of the oven.
In view of the foregoing, there remains a need to provide alternative airflow distribution systems for food processors.
SUMMARY OF THE INVENTION
The present invention provides forced fluid flow distribution systems that can direct exogenously introduced fluid (typically primarily a gas or gas mixture such as air) to flow in a flow path that directs the fluid across food held on a food track having an associated width. As such, the flow includes a lateral directional component and may also include a vertical component.
Certain embodiments are directed to operations for treating food traveling through a food processor. Such embodiments include: (a) moving at least one food item over a predetermined travel path in a food processor having a food travel pathway comprising a moving floor and upwardly extending first and second sidewalls located on opposing sides thereof, the travel pathway having corresponding first and second side portions; (b) introducing exogenous fluid into the food processor from a plurality of inlet ports positioned proximate the first sidewall during the moving step to thereby thermally treat the food; (c) exhausting the fluid from the food processor from a plurality of exhaust ports positioned proximate the second sidewall; and (d) directing the exogenous fluid from the introducing step to travel from the first side portion to the second side portion over the food held on the food travel pathway.
The treatment can comprise a thermal treatment (heating and/or cooling), smoking, chemical, radiation, light, and the like. In certain particular embodiments, the food processor includes a plurality of vertically stacked tiers each having a portion of the fo
Boudewijns André
Chandler Lawrence Alan
Fessmann Ulrich
Hawkins Richard Rodeheaver
Huschka Fabian
ConAgra Foods Inc.
Myers Bigel & Sibley Sajovec, PA
Yeung George C.
LandOfFree
Airflow distribution systems for food processors does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Airflow distribution systems for food processors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Airflow distribution systems for food processors will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3218729