Page 39 - Horticulture Practical Guide

ANNEXURE-VI

Main Points to be Considered

In Making Tomato Ketchup

1. Use plant ripened uniformly red tomatoes as the yellow and greenish portions not only mask the
red colour but also cause browning due to oxidation.

2. Avoid prolonged heating and cooking the product quickly after preparation.
3. Do not use iron or copper equipments at any stage of processing Lycopin (red pigment) turns
brown when it comes in contact with iron. Iron also forms black compounds with the tannin in
the tomatoes and the spices used. Equipments used should be glass lined or made of stainless
steel.
4. As salt bleaches the tomato colour, therefore it is desirable to add it towards the end of the
cooking process.
5. Acetic acid or vinegar may be added towards the end of boiling when the ketchup has thickened
suf iciently, so that the acid does not volatilize away leaving the ketchup de icient in acid and
lavour.
6. About one third of the sugar required should be added initially at the time of commencing the
boiling. This helps to intensify and ix the red tomato colour. The rest of the sugar is added a little
before the ketchup is ready. If the whole of the sugar is added in the beginning itself, the pulp will
have to be boiled for a longer time and at higher temperature with the result the colour of the
ketchup will be adversely affected.
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7. The ketchup should be bottled hot at about 88 c to prevent darkening of its colour and loss of
vitamin content during subsequent storage and distribution.

8. Sodium Benzoate is to be added before Acetic acid in tomato ketchup for better results
otherwise product will be spoiled, as sodium benzoate does not mix with the product in
presence of acid.
9. As the lower head of clove contains tannin which causes browning and black neck ring
formation takes place, if whole cloves are used. Hence cloves should be used only after removing
the lower head.
10. Generally the sugar content in ketchup/sauce varies from 10-26 percent and the salt content of
the product should be 1.3-3.4 percent. The acetic acid should be 1.25- 1.5%. To get a product of
uniform taste and lavour, the total solids in the inished product should be maintained constant
i.e. 28 to 30 percent and in order to increase the viscosity of the ketchup and prevent the
separation of pulp, pectin is usually added to the extend of 0.1 to 0.2 percent by weight of the
inished product.
11. It is however, preferable to add 0.025 percent sodium benzoate to the product before bottling
and then pasteurize the bottles as a safeguard against spoilage during 3 to 4 weeks when the
ketchup in the opened bottle will be used in small proportions at a time.

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