A primary goal in jelly is to obtain a product of uniform and desirable colour, flavour, firmness, texture, and cleanness. A perfect jelly should be transparent, well set, but not too stiff and should have the original flavour of the fruit. It should be of attractive colour and should keep its shape when removed from the mould. When cut it should retain its shape and show a clean cut surface.
Pectin, sugar, acid and water which are the four necessary constituents for jelly making, must be present approximately in the following proportions:
Pectin: 1%
Sugar: 60 to 65 %
Fruit acid: 1%
Water: 33 – 38%
Preparation of Guava Jelly:
Materials:
Guava fruits, sugar, citric acid, Muslin cloth, paraffin wax, Glass bottles, Jel meter, knife, etc.
Procedure Preparation of Guava Jelly:
1. Select just ripe, firm and sound fruits.
2. Wash the fruits thoroughly under cold running water and cut in to the slices with a stainless steel knife.
3. Cook the fruit with an equal weight of water containing 1 % citric acid, for 30 -35 minutes, unit it becomes tender and the pectin comes out in the water.
4. The juice should be extracted by hand press through a thick muslin cloth by putting the soft fruit piece and water in the cloth. The cleaner the juice the brighter the finished products.
5. The juice thus obtained should be finally tested for pectin content. This can be done by using Jel meter, or by Alcohol Test.
6. To every 1 kg of extract add ¾ kg of sugar.
7. The mixture is boiled rapidly till the setting point is reached.
8. The scum which comes out on the surface during boiling should be removed and the boiling should be continued till the temperature reaches 221 0F or when it gives a “ Sheeting Test” ( i.e if hold in the spoon starts dropping down into film position and does not dissolve in water). it is the end point at which the jelly must be removed from the fire.
9. The jelly then poured into previously sterilized glass bottles, allow it to cool and set.
10. Pour a thin layer of melted paraffin wax on the surface of the jelly and sealed the bottles air tight.
11. Label and store the bottles in a cool dry place.
Important Hints for Preparation of Guava Jelly:
1. The final should contain minimum of 45% fruit.
2. Total soluble solids (TSS) should not be less than 65%.
3. Add artificial pectin if fruits are poor in pectin.
4. Permitted colours can be added, if necessary.
5. Jelly should not be sticky, gummy syrupy.
6. Rapid boiling is essential as prolonged boiling results in loss of flavour destroying jellying property of pectin.
7. Good jelly should be gelatinous, clean, sparkling, transparent and of an attractive colour. It should also retain original flavour and aroma of the fruit.
Source: agriinfo