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By goGreen | September 18, 2011
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Sri Lanka has two varieties of pineapple, Kewpine and Mauritius. Kewpine is the cooking pineapple, the fruits are larger and they give a better yield of juice. However, the flavour is not as good as the Mauritius variety which being sweeter is usually eaten fresh. We found that the Mauritius variety made a better jam (a better set, flavour and colour). The pulp from pineapple varies (core included) from pH 3.4-4.1. This means that, to give a jam with a good set the recipe has to be adjusted each time new pulp is used. The yield from whole fruit to usable fruit pulp from Mauritius is approximately 30% and for Kewpine35%. Pineapple contains little or no pectin so pectin must be added when making jam. Pineapples contain the enzyme bromelain, which is a proteolytic enzyme (breaks down proteins). This can cause problems for operators hands which are in contact with the juice for long periods during cutting operations, gloves should therefore be worn and washed each day. To make 200 x 1Ib jars of pineapple jam requires approximately 62kg of sugar and 158kg of fresh pineapple.


In most countries, preservative is not allowed to be added to the jam. Only a residue of preservative is allowed in jam which has been made from fruit pulp which has been stored with chemical preservatives, (l00ppm sulphur dioxide or 500ppm benzoic acid). Citric acid is not a preservative, it is added to adjust the pH. Jams give a gel when there is the correct ratio of pectin to water and the pH is between 2.5-3.45. The optimum pH to give a good gel is pH 3.0.


Equipment list



Pineapple Jam
Intermediate Technology Development Group




Topics: Agri-Business, Food Processing | No Comments »