ITDG 
Interdev Agroalimentaire  

Small-scale production of candied fruit

	Type de fiche	Techniques/Technologies
	Mise en œuvre	ITDG(Royaume Uni)
	
	Zone géographique	Global; 
	Mots clés	FRUIT; FRUIT AU SIROP

	Echelle d’action	Village
	Public(s) cible(s)	Small- and medium-scale food processors

Contexte
Candied fruit is also known as crystallised fruit and osmotically preserved fruit.  It is made by soaking fruit pieces in syrup solution of gradually increasing strength.  During the soaking, sugar is absorbed by the fruit.  The sugar acts as a preservative, increasing the shelf life of the fruit pieces to several months.

In addition to using fresh fruit for the production of candied fruit, the peels of citrus fruits that are discarded after processing can also be used. In this way, candied fruits can provide a secondary product for a fruit juice or jam processor.  This is especially useful if larger food companies are available that are willing to buy the candied peel as an ingredient for their foods.  

Problématique / Objectifs
As with all food processing operations, the selection of raw materials is critical to the final quality of the product.

  All raw material must be of high quality and at the correct stage of maturity.
  Price is an important factor in determining which raw material to use.
  The dried sugared fruit is very hygroscopic, that is, it easily picks up water, which reduces the quality and shelf-life of the product.  It should be kept in sealed polythene bags, away from direct heat and sunlight.

Description/Mise en oeuvre
A number of raw materials can be used for the production of candied fruit.  Orange peel, melon, green papaya, beetroot, turnip and pumpkin are all popular.  The best results are obtained from the first four due to their pectin content, which gives a firmer product with a semi-transparent appearance.  Root vegetables have been successfully used when the preferred fruits are unavailable or are too costly.

The fruit is cut into even-sized cubes and soaked in a brine solution containing 15% salt and 1% calcium chloride.  It is important that all pieces of fruit are submerged in the brine during soaking. This is achieved by placing a wooden plate with a weight on top of the fruit, to prevent pieces from floating.  The calcium in the brine reacts with the pectin in the fruit, resulting in a firmer product with the required transparency.  The salt acts as a preservative.

After two days the fruit is removed from the brine and washed to remove the salt.  The flavour should be checked at this stage to ensure all salt has been removed.  It may be necessary to boil root vegetables such as beetroot or turnip for a few minutes to soften them.

Colouring is added (if it is required) and the fruit pieces are transferred to the first sugar syrup (40 Brix). This is prepared by dissolving 400g sugar and making the volume up to 1 litre.  (The sugar is dissolved in a small amount of water and the volume is then made up to 1 litre using water).  The fruit is left to soak for one day.  After this time it is removed from the syrup, drained off and placed in a stronger syrup solution of 50 Brix. This process is repeated using gradually stronger syrup solutions of 60 and 72 Brix.

The fruit is removed from the final syrup solution and placed on a rack to drain off excess syrup.  The fruit pieces are quickly rinsed in water to help remove surface syrup. This helps to cut down the time required for drying.

The washed fruit pieces are placed in a suitable type of drier- usually a covered solar drier to keep away insects - and allowed to dry for about 1 day.

The dried product is packaged in polythene bags that are heat sealed to keep out moisture. 

Résultats/Eléments chiffrés
The  Brix is a measure of the strength of a syrup solution and is measured using a refractometer. Refractometers cost in the region of $200, therefore may be too expensive for some small-scale processors. It is possible to measure sugar syrup concentration using a hydrometer, which measures specific gravity, density or baume.  This is less effective than using a refractometer as a hydrometer is made from glass, which may get broken and contaminate the food.

The relationship between  Brix, density, specific gravity and baume.

Density	Specific gravity 20 	 Brix 	Baume
1.12	1.13	30	10.57
1.16	1.17	40	21.97
1.23	1.23	50	26.28
1.29	1.29	60	32.49
1.36	1.36	72	38.55

The following pieces of equipment are required:
  Heat source/cooker
  Large pans
  Knives, chopping boards, sieves
  Large plastic bins with lids
  Work tables
  Scales, refractometer or specific gravity hydrometer
  Drier
  Heat sealer

Enseignements
  A key factor in the profitability of this operation lies in the management of the sugar solutions. Sugar is an expensive commodity and this process uses fairly large amounts.  To be efficient, it is essential that the syrup solution is recycled and used for several batches, always adjusting the Brix value to the required level by adding more sugar as necessary.  It is only practical to re-use the syrup solutions about 3 to 4 times, since the heating required to dissolve the extra sugar begins to impart a burnt taste to the syrup.
  It might be possible to utilise the sugar syrups that have to be discarded for the production of sweets and toffees.  The economics and technicalities of this need to be assessed.
  Before producing candied fruit, either as a by-product of another fruit process, or as a product in its own right, it is essential to carry out a market survey to determine the level of demand for the product.  
  Bakeries are useful outlets for this type of product.  They incorporate candied peel and fruits into a variety of biscuits and cakes.  

Auteur : Sue Azam Ali
Saisie le : 03/12/2001 

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