GB1559764A - Dried fruit and vegetable slices - Google Patents

Abstract

The foodstuffs are cleaned and cut into pieces, for example slices. Before freeze-drying, the pieces are then dipped into a solution which prevents discoloration, for example a solution containing 0.1 to 0.5% of ascorbic acid. After freeze-drying, the foodstuff pieces are transferred to a packaging which contains a protective gas, for example nitrogen or carbonic acid, and which is gas- and water-tight. The process gives crisp slices which can be eaten straight from the packaging and which are softened in the mouth by the action of saliva.

Description

(54) DRIED FRUIT AND VEGETABLE SLICES (71) I, WERNER GEORG MUNK of Bergstrasse 12, 7981 Vogt/Ravensburg, Federal Republic of Germany, a citizen of the Federal Republic of Germany, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention is concerned with dried fruit and vegetable slices in a condition of readiness for immediate consumption and of high quality with regard to organoleptic and nutritional physiological characteristics.

In the case of dried fruits hitherto known, the fruits, when in a state of ripeness suitable for processing, are washed, cleaned and cored or stoned and, in the case of, for example, apples, are cut into rings. The rings or halved fruits are frequently gassed with sulphur dioxide and afterwards dried owing to the occurrence of discoloration.

Drying can be performed in installations using hot air or, in southern countries, by means of the sun. However, dried fruits are subject to bacteriological decomposition due to the water content of 10 - 20%.

Storage is also limited by changes in quality, such as hardening, becoming glutinous and the crystallising out of sugars.

It is also known to freeze dry fruits and vegetables. According to the modes of preparation already described, the fruits or vegetables, left in their natural form where possible or in the form of pulp, are dried in a gentle manner to give a powder. In this way, a very low water content can be achieved so that the above mentioned decomposition can be avoided.

In the case of moisture-packing, storage for years can be achieved without any substantial loss of quality. For further processing or also for direct consumption, it is necessary for fruits and vegetables which have been freeze-dried by known methods or dried in some other gentle manner to be reconstituted. The water adsorption of dried fruits and vegetables varies considerably and leads, in many cases, to a product which has a consistency very different from that of the original fruits and vegetables.

It is an object of the present invention to overcome the above-mentioned disadvantages.

Thus, according to the present invention, there is provided dried fruit and vegetables in the form of chips which have been dipped into a solution of a nutritionally acceptable material which prevents discoloration, then freeze-dried and immediately thereafter placed in a packing which contains an inert gas and prevents the ingress of air and moisture.

Freeze-drying immediately before packing prevents the loss of the chip form of the fruit and vegetables during storage.

The present invention eliminates the problems of reconstitution to give a product identical with the natural product. The present invention includes the use of a method producing fruit and vegetable slices by employing freeze-drying or some other gentle drying method, an end product being produced which corresponds in its properties to a foodstuff which is directly ready for consumption, is pleasant-tasting and is crisp and crunchy. Reconstitution takes place by the action of the saliva in the mouth of the consumer, who experiences an agreeable taste sensation. Production of saliva is stimulated to a greater or lesser degree due to the physical composition of the pieces of fruit or vegetable placed in the mouth.

During the reconstitution of the pieces of fruit or vegetable, the saliva causes a modification of the originally dry product to give a soft and swallowable consistency which is experienced by the consumer as an agreeable taste, with an increasing sensation of the flavour of the slices.

Pre-treatment of the fruit or vegetables before freeze-drying is carried out with the object of rendering the freeze-dried material ready for direct consumption. This means, inter alia, that the fruit or vegetable is washed, if necessary cored or stoned and stalked and the pieces of fruit or vegetable for freeze-drying are dimensioned so that, on the one hand, they have a suitable shape for consumption and, on the other hand, leave an agreeable feeling in the mouth. The size of the fruit or vegetable pieces should, therefore, be dimensioned in dependence upon the fruit or vegetable and chosen with regard to the possibility of reconstitution. In the case of apples, slices with a thickness of 6 - 8 mm. are suitable, which remain substantially undamaged during freezedrying and subsequent operations.

A different composition of the dried fruit mass is to be expected, depending upon the variety of apple, the degree of ripeness and the season. For a balanced proportion of fruit acid and fruit sugar, which is of great importance not only for the evaluation of flavour but also for the reconstitution process, it may be necessary to standardise the fruits, i.e. to add appropriate amounts of fruit acid and/or fruit sugar so that. regardless of the content of fruit acid and fruit sugar in the initial fruit, a product will be obtained which always has substantially the same content of fruit acid and fruit sugar.

Thus, for example, fruit pieces can be dipped into a sugar solution, preferred sugars for this purpose including lactose, fructose, glucose and sucrose.

In order to prevent enzymatic or nonenzymatic browning or discoloration, fruit pieces can be dipped into an aqueous ascorbic acid solution, which produces an anti-oxidant effect. This causes the flesh of the fruit to retain its original light colour and not become unpleasantly discoloured during the more or less long processing procedure.

In order to prevent a sticking together of fruit pieces during processing, it can be advantageous to provide the fruit pieces with an organoleptically neutral coating, for example of albumen. This not only prevents the fruit pieces from sticking together dur ing processing but also prevents an exces sively fast adsorption of water during subse quent consumption, which would cause the fruit pieces to adhere to the palate.

Apart from a precise dimensioning of the fruit or vegetable pieces, in order to achieve optimum consumption properties of the end product, the processing should be carried out with as little interruption as possible.

Thus, it is desirable to perform the proces sing stage in one step. If so dictated by the production cycle, an intermediate storage of the fruit or vegetable pieces by deep freezing may be effected before freeze-drying.

The concentration of the aqueous ascorbic acid solution used is preferably in the range of from 0.1 to 0.5% by weight, the concentration of the sugar solution is governed by the nature of the initial material and the concentration of the albumen solution is governed by the desired thickness of the albumen layer. Fruit slices may also be coloured with a foodstuff colouring matter.

In the case of fruit slices, an improvement of the flavour and aroma can be achieved when the slices, before packing, are provided with a coating of chocolate and/or albumen or similar coatings. Furthermore, if desired, fruit and vegetable chips can be blanched before freeze-drying.

The slices which can be used include apples, pears, carrots, celery and like fruit and vegetables having the consistency of apples. Chips of different products may also be packed within a single package.

The fruit and vegetable slices according to the present invention are ready for direct consumption after freeze-drying and are pleasant-tasting crisp and crunchy foodstuffs. This condition is retained for long periods of time by packing in an inert gaseous atmosphere, for example nitrogen, using a packing material which prevents the access of air and moisture.

WHAT WE CLAIM IS: 1. Dried fruits and vegetables in the form of chips which have been dipped into a solution of a nutritionally acceptable material which prevents discoloration, then freeze-dried and immediately thereafter placed in a packing which contains an inert gas and prevents the ingress of air and moisture.

2. Fruit and vegetable slices according to claim 1, wherein the solution used to prevent discoloration is an aqueous solution of ascorbic acid.

3. Fruit and vegetable slices according to claim 1, where in the aqueous solution of ascorbic acid has a concentration of from 0.1 to 0.5% by weight.

4. Fruit and vegetable slices according to any of the preceding claims, wherein a sugar and/or albumen and/or chocolate is applied to the chips before packing.

5. Fruit and vegetable slices according to claim 4, wherein the sugar used is lactose, fructose, glucose or sucrose.

6. Fruit and vegetable slices according to any of the preceding claims, wherein foodstuff colourings and/or flavourings are added.

7. Fruit and vegetable slices according to any of the preceding claims, wherein the chips are made from apples, pears, carrots, celery and like fruits and vegetables with the consistency of apples.

8. Fruit and vegetable slices according

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (9)

**WARNING** start of CLMS field may overlap end of DESC **. the flavour of the slices. Pre-treatment of the fruit or vegetables before freeze-drying is carried out with the object of rendering the freeze-dried material ready for direct consumption. This means, inter alia, that the fruit or vegetable is washed, if necessary cored or stoned and stalked and the pieces of fruit or vegetable for freeze-drying are dimensioned so that, on the one hand, they have a suitable shape for consumption and, on the other hand, leave an agreeable feeling in the mouth. The size of the fruit or vegetable pieces should, therefore, be dimensioned in dependence upon the fruit or vegetable and chosen with regard to the possibility of reconstitution. In the case of apples, slices with a thickness of 6 - 8 mm. are suitable, which remain substantially undamaged during freezedrying and subsequent operations. A different composition of the dried fruit mass is to be expected, depending upon the variety of apple, the degree of ripeness and the season. For a balanced proportion of fruit acid and fruit sugar, which is of great importance not only for the evaluation of flavour but also for the reconstitution process, it may be necessary to standardise the fruits, i.e. to add appropriate amounts of fruit acid and/or fruit sugar so that. regardless of the content of fruit acid and fruit sugar in the initial fruit, a product will be obtained which always has substantially the same content of fruit acid and fruit sugar. Thus, for example, fruit pieces can be dipped into a sugar solution, preferred sugars for this purpose including lactose, fructose, glucose and sucrose. In order to prevent enzymatic or nonenzymatic browning or discoloration, fruit pieces can be dipped into an aqueous ascorbic acid solution, which produces an anti-oxidant effect. This causes the flesh of the fruit to retain its original light colour and not become unpleasantly discoloured during the more or less long processing procedure. In order to prevent a sticking together of fruit pieces during processing, it can be advantageous to provide the fruit pieces with an organoleptically neutral coating, for example of albumen. This not only prevents the fruit pieces from sticking together dur ing processing but also prevents an exces sively fast adsorption of water during subse quent consumption, which would cause the fruit pieces to adhere to the palate. Apart from a precise dimensioning of the fruit or vegetable pieces, in order to achieve optimum consumption properties of the end product, the processing should be carried out with as little interruption as possible. Thus, it is desirable to perform the proces sing stage in one step. If so dictated by the production cycle, an intermediate storage of the fruit or vegetable pieces by deep freezing may be effected before freeze-drying. The concentration of the aqueous ascorbic acid solution used is preferably in the range of from 0.1 to 0.5% by weight, the concentration of the sugar solution is governed by the nature of the initial material and the concentration of the albumen solution is governed by the desired thickness of the albumen layer. Fruit slices may also be coloured with a foodstuff colouring matter. In the case of fruit slices, an improvement of the flavour and aroma can be achieved when the slices, before packing, are provided with a coating of chocolate and/or albumen or similar coatings. Furthermore, if desired, fruit and vegetable chips can be blanched before freeze-drying. The slices which can be used include apples, pears, carrots, celery and like fruit and vegetables having the consistency of apples. Chips of different products may also be packed within a single package. The fruit and vegetable slices according to the present invention are ready for direct consumption after freeze-drying and are pleasant-tasting crisp and crunchy foodstuffs. This condition is retained for long periods of time by packing in an inert gaseous atmosphere, for example nitrogen, using a packing material which prevents the access of air and moisture. WHAT WE CLAIM IS:

1. Dried fruits and vegetables in the form of chips which have been dipped into a solution of a nutritionally acceptable material which prevents discoloration, then freeze-dried and immediately thereafter placed in a packing which contains an inert gas and prevents the ingress of air and moisture.

2. Fruit and vegetable slices according to claim 1, wherein the solution used to prevent discoloration is an aqueous solution of ascorbic acid.

3. Fruit and vegetable slices according to claim 1, where in the aqueous solution of ascorbic acid has a concentration of from 0.1 to 0.5% by weight.

4. Fruit and vegetable slices according to any of the preceding claims, wherein a sugar and/or albumen and/or chocolate is applied to the chips before packing.

5. Fruit and vegetable slices according to claim 4, wherein the sugar used is lactose, fructose, glucose or sucrose.

6. Fruit and vegetable slices according to any of the preceding claims, wherein foodstuff colourings and/or flavourings are added.

7. Fruit and vegetable slices according to any of the preceding claims, wherein the chips are made from apples, pears, carrots, celery and like fruits and vegetables with the consistency of apples.

8. Fruit and vegetable slices according

to any of the preceding claims, wherein blanching is carried out before the freezedrying.

9. Fruit and vegetable slices according to claim 1, substantially as hereinbefore described.