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Lesson 20. GLAZED AND CRYSTALLIZED FRUIT
Module 5. Jam, jelly, marmalade, and glazed and crystallized fruits
Lesson 20
GLAZED AND CRYSTALLIZED FRUIT
20.1 Introduction
A fruit impregnated with cane sugar and glucose, and subsequently drained and dried, is called a Candied fruit. Candied fruit covered or coated with a thin transparent coating of sugar, which imparts to it a glossy appearance, is called Glazed fruit. When candied fruit is coated with crystals of sugar, either by rolling it in finely powdered sugar or by allowing the sugar crystals from a dense syrup to deposit on it, it becomes what is called Crystallized fruit.
20.2 Candied Fruit
The process is similar to the one employed in preparing fruit preserves, but here the fruit is impregnated with a higher percentage of sugar or glucose; the total sugar content is about 75.0%. A certain amount of invert sugar or glucose is substituted in place of cane sugar.
The fruits suitable for such preparation are those that possess pronounced flavor, such as pineapple, peach, peels of orange, lemon, grapefruit, citrus, cherry, etc. Use of slightly underripe fruit helps in preventing formation of jam-like consistency in the syruping process.
The sweeteners used maybe Confectioner’s glucose (corn syrup, crystal syrup or commercial glucose), dextrose, invert sugar, etc.
20.2.1 Syruping treatment
The prepared fruit or peel is boiled in a sugar syrup of 30°Brix containing 3 parts of cane sugar and 1 part of corn syrup and then left in the syrup for about 24 h. The strength of syrup is raised to 40°Brix by adding a mixture of cane sugar and glucose syrup. The process is repeated and the strength of syrup is raised by 10°Brix to 65°Brix and then by 5°Brix on alternate days, until the final concentration of sugar reaches about 75°Brix, when the process is complete.
It is desirable to have cane sugar and invert sugar in the final syrup in nearly equal proportion. The acidity should be maintained at 0.1% by adding a small dose of acid daily along with added sugar, to ensure adequate inversion.
20.2.2 Draining and drying
After syrup treatment is over, the fruit is removed from the syrup and drained for about half an hour. The fruit or peel is wiped with a wet sponge. Sometimes it is dipped for a moment in boiling water to remove the adhering syrup. This is followed by slow drying in the shade, or in a drier at about 66°C for 8-10 h. Candied citrus peel needs drying for 10-12 h.
20.3 Examples of Candied Fruit Products
20.3.1 Candied citrus peels
Candied citrus peels are highly popular for festive occasions like Christmas, Diwali, etc. They are manufactured and sold in large quantities in several parts of the world. They are useful as flavouring materials in cakes, puddings, etc. Citrus peels, especially orange peels, are waste products in the manufacture of orange juice, squash, segments, etc. Thick rinds of citrus fruits like orange, lemon, grape fruit, citrus, and pummelo are used for candying.
After the peels are prepared, they are covered with a cold syrup of 30°Brix in a vessel and left for 48 h. On the 3rd day, the strength will be less than 30°Brix, which is raised by 10oBrix and the peels boiled in this syrup for about 5 min. The process is repeated until the strength reaches 60°Brix. At this stage, citric or tartaric acid is added at the rate of 1.25 g for every kg of peels. Alternatively, glucose or invert syrup may be added up to a maximum of 50.0% of the cane sugar used. The strength of the syrup is then raised to 75°Brix by 5°Brix every succeeding day. The peels are then left in this syrup for 2-3 weeks. Finally, they are taken out from the syrup and dried on wire mesh trays at room temperature until they are no longer sticky. They may also be dried at 49°C for 2-3 h in a drier.
20.3.2 Petha (Candied ash gourd)
Take fully, mature petha (Ash Gourd) and cut longitudinally into fairly large piece. Remove the fluffy portion from inside of the slices and peel each side separately. Soak the peeled slices for about 30 min in lime water, diluted with three times the quantity of water. Prick the pieces with a stainless steel needle or fork and cut the slice into pieces of suitable size. Keep the pieces in lime water again and let it stand overnight. Prepare 2-3% alum solution and bring it to boil. Boil the pieces in this solution till they become tender. Drain and cool them in running cold water. Sodium sulphite may be used while cooking the slices, to render the pieces white. Arrange the prepared slices in alternate layers with sugar (half their weight) in a vessel and allow standing for 24 h. During this period, the pieces will give out sufficient water for the sugar to dissolve. The syrup will be about 36-38°Brix. Add sugar to raise the strength of syrup to 59-60°Brix. Add citric/tartaric acid at the rate of 0.62 g/kg of sugar used. Alternatively, add 25% by weight of invert sugar or corn syrup to raise the syrup strength. Boil the slices in syrup for 10 min and set then aside for 24 h. Later on, increase the strength of the syrup by 5°Brix on every alternate day till it reaches 70°Brix. Allow the pieces to remain in this syrup for 4-6 weeks.
For candying, bring the whole mass of petha and syrup to a boil and while still hot, drain the syrup. Roll the drained pieces in finely powdered sugar and dry them on trays at room temperature.
Fig. 20.1 Dry petha from ash gourd
20.4 Glazing of Fruit
The syrup needed for glazing process is made by boiling a mixture of cane sugar and water in the proportion of 2:1, in a steam pan at 113-114°C and skimming the impurities as they surface. Heat is stopped and the syrup cooled to 93°C. Granulation of the sugar is achieved by rubbing the syrup with a wooden ladle on the side of the pan. Dried candied fruit are passed through the granulated portion of the syrup, one by one, by means of a form, and then placed on trays that are kept in a warm, dry room. To hasten the process, the fruit may be dried in a drier at 49°C for 2-3 h. When it becomes crisp, it is packed in air-tight containers.
20.5 Crystallized Fruit
In this case syrup of 70°Brix is employed. It is placed in a large deep vessel and allowed to cool to room temperature. To avoid premature granulation of sugar, a sheet of waxed paper is placed on the surface of the syrup. The candied fruit is placed on a wire mesh tray, which in turn is placed in a deep vessel. The cooled syrup is then gently poured over the fruit so as to cover it entirely. To prevent the fruit from floating, another wire-mesh tray is placed on it and a sheet of waxed paper is placed on the surface of the syrup. The whole mass is left undisturbed for 12-18 h, at the end of which a thin crust of crystallized sugar is formed. The tray containing the fruit is then removed carefully from the pan, and the surplus syrup drained off. The drained fruit are spread in a single layer on wire mesh trays and allowed to dry at room temperature or in driers at about 49°C.
Fig. 20.2 Glazed fruit
20.5.1 Improved mechanization of preparing glazed and crystallized fruit
Vacuum concentration process of Cruess is an improvement over the conventional one. The fruit and the syrup are maintained at 60oC and the concentration of sugar is raised at the rate of 1°Brix per hour; a part of the syrup is continuously withdrawn and concentrated in a Cascade or Calandria type of evaporator.
Using modified technique, the syrup strength could be raised from initial 30° to 70°Brix in 40 h. The ash gourd and apple preserves made by this method are highly satisfactory.
20.5.2 Spoilage of glazed and crystallized fruit
There is a likelihood of spoilage occurring due to fermentation, especially in the initial stages of preparation of preserves and candies when the concentration of sugar in the syrup is low. This can be controlled by boiling the product at proper intervals. If the candied and crystallized fruit are stored under humid conditions, they throw off some of their sugar owing to absorption of moisture from the air. Later on, they become mouldy, if they are packed in wet rather than dry containers. The danger of mould infestation may accrue if such fruit is not sufficiently dried.
Lesson 20
GLAZED AND CRYSTALLIZED FRUIT
20.1 Introduction
A fruit impregnated with cane sugar and glucose, and subsequently drained and dried, is called a Candied fruit. Candied fruit covered or coated with a thin transparent coating of sugar, which imparts to it a glossy appearance, is called Glazed fruit. When candied fruit is coated with crystals of sugar, either by rolling it in finely powdered sugar or by allowing the sugar crystals from a dense syrup to deposit on it, it becomes what is called Crystallized fruit.
20.2 Candied Fruit
The process is similar to the one employed in preparing fruit preserves, but here the fruit is impregnated with a higher percentage of sugar or glucose; the total sugar content is about 75.0%. A certain amount of invert sugar or glucose is substituted in place of cane sugar.
The fruits suitable for such preparation are those that possess pronounced flavor, such as pineapple, peach, peels of orange, lemon, grapefruit, citrus, cherry, etc. Use of slightly underripe fruit helps in preventing formation of jam-like consistency in the syruping process.
The sweeteners used maybe Confectioner’s glucose (corn syrup, crystal syrup or commercial glucose), dextrose, invert sugar, etc.
20.2.1 Syruping treatment
The prepared fruit or peel is boiled in a sugar syrup of 30°Brix containing 3 parts of cane sugar and 1 part of corn syrup and then left in the syrup for about 24 h. The strength of syrup is raised to 40°Brix by adding a mixture of cane sugar and glucose syrup. The process is repeated and the strength of syrup is raised by 10°Brix to 65°Brix and then by 5°Brix on alternate days, until the final concentration of sugar reaches about 75°Brix, when the process is complete.
It is desirable to have cane sugar and invert sugar in the final syrup in nearly equal proportion. The acidity should be maintained at 0.1% by adding a small dose of acid daily along with added sugar, to ensure adequate inversion.
20.2.2 Draining and drying
After syrup treatment is over, the fruit is removed from the syrup and drained for about half an hour. The fruit or peel is wiped with a wet sponge. Sometimes it is dipped for a moment in boiling water to remove the adhering syrup. This is followed by slow drying in the shade, or in a drier at about 66°C for 8-10 h. Candied citrus peel needs drying for 10-12 h.
20.3 Examples of Candied Fruit Products
20.3.1 Candied citrus peels
Candied citrus peels are highly popular for festive occasions like Christmas, Diwali, etc. They are manufactured and sold in large quantities in several parts of the world. They are useful as flavouring materials in cakes, puddings, etc. Citrus peels, especially orange peels, are waste products in the manufacture of orange juice, squash, segments, etc. Thick rinds of citrus fruits like orange, lemon, grape fruit, citrus, and pummelo are used for candying.
After the peels are prepared, they are covered with a cold syrup of 30°Brix in a vessel and left for 48 h. On the 3rd day, the strength will be less than 30°Brix, which is raised by 10oBrix and the peels boiled in this syrup for about 5 min. The process is repeated until the strength reaches 60°Brix. At this stage, citric or tartaric acid is added at the rate of 1.25 g for every kg of peels. Alternatively, glucose or invert syrup may be added up to a maximum of 50.0% of the cane sugar used. The strength of the syrup is then raised to 75°Brix by 5°Brix every succeeding day. The peels are then left in this syrup for 2-3 weeks. Finally, they are taken out from the syrup and dried on wire mesh trays at room temperature until they are no longer sticky. They may also be dried at 49°C for 2-3 h in a drier.
20.3.2 Petha (Candied ash gourd)
Take fully, mature petha (Ash Gourd) and cut longitudinally into fairly large piece. Remove the fluffy portion from inside of the slices and peel each side separately. Soak the peeled slices for about 30 min in lime water, diluted with three times the quantity of water. Prick the pieces with a stainless steel needle or fork and cut the slice into pieces of suitable size. Keep the pieces in lime water again and let it stand overnight. Prepare 2-3% alum solution and bring it to boil. Boil the pieces in this solution till they become tender. Drain and cool them in running cold water. Sodium sulphite may be used while cooking the slices, to render the pieces white. Arrange the prepared slices in alternate layers with sugar (half their weight) in a vessel and allow standing for 24 h. During this period, the pieces will give out sufficient water for the sugar to dissolve. The syrup will be about 36-38°Brix. Add sugar to raise the strength of syrup to 59-60°Brix. Add citric/tartaric acid at the rate of 0.62 g/kg of sugar used. Alternatively, add 25% by weight of invert sugar or corn syrup to raise the syrup strength. Boil the slices in syrup for 10 min and set then aside for 24 h. Later on, increase the strength of the syrup by 5°Brix on every alternate day till it reaches 70°Brix. Allow the pieces to remain in this syrup for 4-6 weeks.
For candying, bring the whole mass of petha and syrup to a boil and while still hot, drain the syrup. Roll the drained pieces in finely powdered sugar and dry them on trays at room temperature.
Fig. 20.1 Dry petha from ash gourd
20.4 Glazing of Fruit
The syrup needed for glazing process is made by boiling a mixture of cane sugar and water in the proportion of 2:1, in a steam pan at 113-114°C and skimming the impurities as they surface. Heat is stopped and the syrup cooled to 93°C. Granulation of the sugar is achieved by rubbing the syrup with a wooden ladle on the side of the pan. Dried candied fruit are passed through the granulated portion of the syrup, one by one, by means of a form, and then placed on trays that are kept in a warm, dry room. To hasten the process, the fruit may be dried in a drier at 49°C for 2-3 h. When it becomes crisp, it is packed in air-tight containers.
20.5 Crystallized Fruit
In this case syrup of 70°Brix is employed. It is placed in a large deep vessel and allowed to cool to room temperature. To avoid premature granulation of sugar, a sheet of waxed paper is placed on the surface of the syrup. The candied fruit is placed on a wire mesh tray, which in turn is placed in a deep vessel. The cooled syrup is then gently poured over the fruit so as to cover it entirely. To prevent the fruit from floating, another wire-mesh tray is placed on it and a sheet of waxed paper is placed on the surface of the syrup. The whole mass is left undisturbed for 12-18 h, at the end of which a thin crust of crystallized sugar is formed. The tray containing the fruit is then removed carefully from the pan, and the surplus syrup drained off. The drained fruit are spread in a single layer on wire mesh trays and allowed to dry at room temperature or in driers at about 49°C.
Fig. 20.2 Glazed fruit
20.5.1 Improved mechanization of preparing glazed and crystallized fruit
Vacuum concentration process of Cruess is an improvement over the conventional one. The fruit and the syrup are maintained at 60oC and the concentration of sugar is raised at the rate of 1°Brix per hour; a part of the syrup is continuously withdrawn and concentrated in a Cascade or Calandria type of evaporator.
Using modified technique, the syrup strength could be raised from initial 30° to 70°Brix in 40 h. The ash gourd and apple preserves made by this method are highly satisfactory.
20.5.2 Spoilage of glazed and crystallized fruit
There is a likelihood of spoilage occurring due to fermentation, especially in the initial stages of preparation of preserves and candies when the concentration of sugar in the syrup is low. This can be controlled by boiling the product at proper intervals. If the candied and crystallized fruit are stored under humid conditions, they throw off some of their sugar owing to absorption of moisture from the air. Later on, they become mouldy, if they are packed in wet rather than dry containers. The danger of mould infestation may accrue if such fruit is not sufficiently dried.
Last modified: Thursday, 1 November 2012, 7:22 AM