GB2259357A

GB2259357A - Food handling and cooling system

Info

Publication number: GB2259357A
Application number: GB9216578A
Authority: GB
Inventors: Richard Frederick Targett
Original assignee: Distillers MG Ltd
Current assignee: Distillers MG Ltd
Priority date: 1991-09-04
Filing date: 1992-08-05
Publication date: 1993-03-10
Also published as: GB9216578D0

Abstract

In a food handling system. food is supported inside an at least partially enclosed compartment (3). A flow of CO2 gas and entrained CO2 snow is directed into the compartment (3) from a CO2 outlet (5). The snow is distributed substantially evenly over the food and the compartment is subsequently closed. In a preferred example, the outlet includes a solid tube (7) mounted to a body which is held by the user. CO2 is dispensed from the end of the tube away from the body. The other end of the tube is connected to a flexible supply line (6). A deflector may be used to position the snow on the food. <IMAGE>

Description

FOOD HANDLING SYSTEM The present invention relates to a food handling system and in particular to a system for chilling food in circumstances where conventional refrigeration is not possible. Such a system might be used, for example, with airline trollies for distributing food to passengers.

Conventionally, food inside airline trollies has been pre-chilled and then maintained at a relatively low temperature by, for example, placing slices of solid CO2 with the food inside the trolley. The dry ice slices are either compressed as solid slices from snow or pellets or are sawn from larger dry ice blocks. A mixture of chilled air and CO2 then permeates the body of the trolley, cooling the food. However, while such techniques have made it possible to maintain food at relatively low temperatures, it has not hitherto been possible reliably to maintain temperatures significantly lower than +8 CC. Moreover, sometimes it is not possible to place the CO2 slices immediately adjacent the food, the CO2 instead being placed on top of the trolley, further limiting the ability to maintain low temperatures.

According to the present invention, a food handling system includes the steps of supporting the food inside an at least partially enclosed compartment, directing a flow of CO2 gas and entrained CO2 snow into the compartment from a CO2 outlet so as to distribute the CO2 snow substantially evenly over the food, and closing the compartment.

Preferably the outlet is a mobile freely directable outlet.

The present inventor has found that by using a freely directable CO2 outlet it is possible to distribute CO2 snow evenly within a compartment such as the interior of an airline trolley. The cooling effect is then much more evenly distributed than was the case when, as in the prior art, solid slices of CO2 were relied upon. It is found to be possible, using the system of the present invention, reliably to maintain food temperatures significantly below the +80C maximum.

Preferably the at least partially enclosed compartment forms part of a trolley divided into a number of such compartments, and snow is directed into each of the compartments.

Preferably the CO2 outlet is a generally tubular outlet adapted to be held by the operator and connected by a line, which is preferably flexible, to a reservoir of liquid CO2.

Preferably the outlet further comprises a manually controllable valve for controlling the flow of CO2.

Preferably the outlet includes a solid tube mounted to a body adapted to be held by the user, CO2 being dispensed from the end of the tube away from the body, the other end of the tube being connected to the flexible supply line.

Preferably the valve is a solenoid valve mounted in the path of the CO2 at the end of the tube adjacent the body and controlled by a switch mounted on the body.

One example of a system in accordance with the present invention will now be described in detail with reference to the accompanying drawings, in which: Figure 1 is a perspective view showing the system in use; Figure 2 is a perspective view of an outlet in use; and, Figure 3 is a plan view of a detail of the outlet of Figure 2.

In a food handling system trays 1A, 1B carrying wrapped food portions 2A, 2B are placed within respective compartments 3A, 3B of a trolley 4. A hand-held CO2 outlet 5, which is described in further detail below, is used to direct a flow of CO2 snow into the compartments 3A, 3B of the trolley 4 so as to cover the foodstuffs on the trays together with the inside walls of the trolley 4. The outlet 5 is connected via flexible line 6 to a liquid CO2 reservoir in an ambient temperature cylinder. As it is discharged through the nozzle to atmospheric pressure approximately 40% of the liquid is converted into solid and the remaining 60t becomes CO2 vapour. The flow of CO2 from the supply line 6 to the nozzle 7 of the CO2 outlet is controlled by a solenoid valve.A push button 8 mounted on the body of the outlet is operated by the user to open the valve allowing the CO2 to flow through the outlet. The CO2 is emitted as a mixture of gas and snow entrained in the gas which is then "shot" from the end of the tube and directed as required in order to effect even distribution of the cooling medium into and around the food containers.

The construction of the outlet is shown in further detail in Figures 2 and 3. The nozzle 7 takes the form of a tube. A handle 9 is mounted to one end of the tube and the push button 8 is located on this handle. The solenoid valve 10 is mounted on the end of the tube adjacent the handle 9. CO2 from the flexible supply line 6 flows through the valve 10 into the nozzle 7. A deflector 11 is mounted to the other end of the nozzle 7 via a member 12.

The narrower portion llA and the broader portion llB of the deflector plate extend at different angles to the central axis of the nozzle 7 so that with the nozzle held as shown in Figure 2 the deflector plate directs the snow from the end of the nozzle forwards in a generally horizontal plane so as to pass into the trolley between the trays, covering the food on the trays. The snow is deflected at an acute angle a to the axial direction of the nozzle 7.

Although it is much preferred that a freely directable outlet mounted on a flexible line is used, alternatively for some applications it may be possible to use a static outlet and a rigid line.

Claims

1. A food handling system including the steps of supporting the food inside an at least partially enclosed compartment, directing a flow of CO2 gas and entrained CO2 snow into the compartment from a CO2 outlet so as to distribute the CO2 snow substantially evenly over the food, and closing the compartment.

2. A system according to claim 1, in which the outlet is a mobile freely directable outlet.

3. A system according to claim 1 or 2, in which the at least partially enclosed compartment forms part of a trolley divided into a number of such compartments, and snow is directed into each of the compartments.

4. A system according to any one of the preceding claims, in which the CO2 outlet is a generally tubular outlet adapted to be held by the operator connected by a line to a reservoir of liquid CO2.

5. A system according to claim 4, in which the line is flexible.

6. A system according to claim 4 or 5, in which the outlet further comprises a manually controllable valve for controlling the flow of COz.

7. A system according to claim 6, in which the outlet includes a solid tube mounted to a body adapted to be held by the user, CO2 being dispensed from the end of the tube away from the body, the other end of the tube being connected to the flexible supply line.

8. A system according to claim 6 or 7, in which the valve is a solenoid valve mounted in the path of the CO2 at the end of the tube adjacent the body and controlled by a switch mounted on the body.

9. A system according to claim 4, or any one of claims 5 to 8 when directly or indirectly dependent on claim 4, in which the outlet includes a deflector positioned towards the end of the outlet and extending at an angle to the axial direction of the outlet, the deflector being arranged, in use, to direct gas and snow forwards in a generally horizontal plane.

10. A food handling system substantially as described with respect to the accompanying drawings.

11. A hand-held CO2 outlet adapted for use in a system according to any one of the preceding claims.

12. A hand-held CO2 outlet substantially as described with respect to the accompanying drawings.