GB2075650A

GB2075650A - Device and method for providing warning of thawing in frozen goods

Info

Publication number: GB2075650A
Application number: GB8108449A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-03-20
Filing date: 1981-03-18
Publication date: 1981-11-18
Also published as: AU6853381A

Abstract

A warning device 1 suitable for use with a frozen commodity 5 to indicate whether the commodity has been maintained in a frozen state comprises an object preformed into a solid state in a selected shape, such as a marble 2, for example by the freezing of a liquid. The object 2 is enclosed within a transparent envelope 3 and is maintained in proximity with the frozen commodity. If the commodity is subjected to ambient temperature permitting thawing, at least partially, of the commodity, at least part of the object 2 deforms by changing its state. Upon re-freezing of the commodity, the object 2 re- freezes in a shape other than its original shape and this provides an immediately visible warning of the thawing of the commodity. <IMAGE>

Description

SPECIFICATION Device and method for providing warning of thawing in frozen goods This invention relates to warning devices for use with frozen goods. The invention relates particularly to warning devices for use with perishable goods such as foodstuffs sold to the public.

A potential difficulty in respect of frozen foodstuffs lies in the fact that there is currently, so far as the applicant is aware, no way a purchaser may determine whether a commodity sold in frozen state has been maintained in such state up to the time of sale. If the commodity is proved to have been thawed from its frozen state and thereafter to have been re-frozen, a purchaser's willingness to purchase the commodity may be effected.

This particularly of relevance in the case of foodstuffs which may tend to lose of its liquid content and hence of nutrients upon being thawed. The cellular structure of certain foodstuffs is also known to deteriorate with repeated freezing and thawing.

An object of the present invention is the provision of means whereby it may readily be determined whether a commodity in a frozen state has been maintained in such state.

According to the invention a warning device suitable for use with a frozen commodity to indicate whether the commodity has been maintained in a frozen state comprises an object preformed into a solid state in a selected shape, the object being adapted to be maintained in proximity with the frozen commodity, at least part of the object deforming by changing its state when the commodity is subjected to ambient temperature permitting thawing, at least partially, of the commodity.

Further according to the invention the object is preformed by the freezing of a liquid, for example, water. In another form of the invention the liquid may be one having a freezing point higher than that of water. In a preferred form the object is preformed into the shape of a sphere or spheroid and is coloured by means of colouring material.

Further according to the invention a sealed container is provided for housing the object, preferably a transparent envelope. In a preferred application, the warning device according to the invention is adapted to be located within a package containing the frozen commodity.

Further according to the invention a method of warning to indicate whether a frozen commodity has been maintained in a frozen state comprises the steps of providing an object preformed into a solid state in a selected shape and locating the object in proximity with the frozen commodity, at least part of the object deforming by changing its state when the commodity is subjected to ambient temperature permitting thawing, at least partially, of the commodity.

In a preferred form of the method of the invention the object is located within a package containing the frozen commodity and the object is housed in a transparent, sealed container.

The warning device may be of shapes other than spherical but the avoidance of corners therein is desirable since the dropping of an article might easily result in a break up of the warning device.

To illustrate the invention a preferred example is described hereunder with reference to the accompanying drawings in which: Figure 1 is a perspective view of a warning device according to the invention; and Figure 2 is a perspective view of a package of frozen foodstuff incorporating the warning device.

The warning device 1 comprises a spherical marble 2 formed from frozen coloured water or other suitable liquid which is loosely placed in a sealed transparent envelope 3 and the envelope in turn is located strategically inside a package 4 of frozen foodstuff 5 the package 4 also being transparent.

To enable the marble 2 to be placed in the envelope 3 the latter may be provided in an open-ended form. Once the frozen marble 2 is located in the envelope 3, it may be sealed in any suitable manner, for example by heating sealing along line 6.

If the foodstuff 5 has been maintained continuously in a frozen state the marble 2 should show no material change from its basic spherical shape. On the other hand, if the package 4 has been subjected to temperatures permitting thawing of the foodstuff, even if only partially, melting of the marble 2 at that stage, wholly or partially, will give rise to a detectable change in its shape. Subsequent re-freezing of the foodstuff will merely result in the liquid produced from the melting of the marble 2 re-freezing to a shape other than spherical.

In those cases where the packaging of the frozen foodstuff is not transparent, for instance, where a paper carton is used, an observation window may be provided in the carton and the warning device of the invention may be located in the interior of the carton behind the observation window where it may be held in position with the aid of adhesive tape or the like.

It is anticipated that it will be easier to detect changes in the shape of the marble 2 by using a coloured liquid and any suitable colouring material may be used for this purpose.

To facilitate rapid location of the warning device in a package the marbles may be prepacked in suitable envelopes which are linked together in a ribbon from which individual envelopes may be removed along tear lines.

In such a case access to the interior of the envelopes for the purpose of placing the marbles therein may be provided through slits in the envelopes which may be sealed with the aid of adhesive tape or the like. In suitable circumstances the envelopes may be made of sufficiently rigid material to prevent accidental crushing of the marbles.

Whilst it is considered preferable to have the warning device inside the package of frozen foodstuff, it may also be attached to the outside of it, for instance, on a short length of string.

Many other examples of the invention exist each differing from the other in matters of detail only. For example, substances other than water may be used to provide the warning device of the invention. A polyhydric alcohoi, glycerol, has a melting point of 18"C.

If such a substance or a solution thereof in water is used, it will permit substantial thawing of the frozen foodstuff before the device itself melts. Such a warning device will be used to give warning of more than superficial thawing of the foodstuff. Clearly many different substances may be chosen for this purpose and characteristics such as melting point and latent heat of fusion will be of importance depending on the required use of the warning device.

Claims

1. A warning device suitable for use with a frozen commodity to indicate whether the commodity has been maintained in a frozen state, the device comprising an object preformed into a solid state in a selected shape, the object being adapted to be maintained in proximity with the frozen commodity, at least part of the object deforming by changing its state when the commodity is subjected to ambient temperature permitting thawing, at least partially, of the commodity.

2. A warning device according to claim 1 wherein the object is preformed by the freezing of a liquid.

3. A warning device according to claim 2 wherein the liquid is water.

4. A warning device according to claim 2 wherein the liquid is one having a melting point higher than that of ice.

5. A warning device according to any one of claims 2 to 4 wherein the object is preformed into the shape of a sphere or spheroid.

6. A warning device according to any one of claims 2 to 5 wherein the object is coloured by means of colouring material.

7. A warning device according to any one of the preceding claims including a sealed container for housing the object.

8. A warning device according to claim 7 wherein the sealed container comprises a transparent envelope.

9. A warning device according to any one of the preceding claims wherein the device is adapted to be located within a package containing the frozen commodity.

10. A warning device substantially as herein described with reference to the accompanying drawings.

11. A method of warning to indicate whether a frozen commodity has been maintained in a frozen state comprising the steps of providing an object preformed into a solid state in a selected shape and locating the object in proximity with the frozen commodity, at least part of the object deforming by changing its state when the commodity is subjected to ambient temperature permitting thawing, at least partially, of the commodity.

1 2. A method according to claim 11 wherein the object is located within a package containing the frozen commodity.

1 3. A method according to claim 11 or claim 1 2 wherein the object is housed in a transparent sealed container.

14. A method of indicating whether a frozen commodity has been maintained in a frozen state substantially as herein described with reference to the accompanying drawings.