WHEN there is tomato glut, farmers normally incur losses yet they can make jam out of the fruits and sell it for a longer time and at a higher price. Indeed, you can make jam from virtually any fruit: avocado, banana or strawberry, just name it.
Joseph Mwangi, a food technologist at Wambugu Farm, describes jam as viscous semi-solid foods containing not less than 45 parts by weight of fruit ingredients (everything in the fruit that is edible) to which 55 parts by weight of sugar have been added.
To make jam, prepare a homogeneous mash from the edible fleshy part of the fruit by pulping it.
Mix the fruit mass with 75 per cent of the required sugar and adjust the PH (acidity or alkalinity) to 3.3 with 20 per cent citric acid solution. Boil for 30 minutes.
Mix the remaining sugar thoroughly with pectin, a preservative. The total added sugar should be equal to the weight of the fruit ingredient.
Add the sugar-pectin mixture and continue boiling until the jam sets, mix three litres of pulp with 1kg of sugar.
Fill it hot into glass jars and later cool in cold running tap water. Mwangi advises that the preserve should be hot-filled at 82 to 85 degrees Celsius in suitable glass or plastic jars.
“If the preserve is too hot then the steam will condense on the inside of the lid and drop down onto the surface and allow mould growth. If the temperature is too low, the preserve will thicken and be difficult to pour and a partial vacuum will not form in the jar,” he says.
