Total Soluble Solids (TSS)

Total soluble solids are solids that are dissolved within a substance. A common total soluble solid is sugar. The total mass of a jam is made up of ingredients like sugar, fruit pulp, pectin, preservatives, salt, food colour and other soluble solids present naturally or added in combining form. All of these make the ‘total soluble contents’ of a jam. High total soluble contents do not necessarily denote high fruit pulp since sugar, pectin and other preservatives also increase the amount of total soluble contents.

As per Food Safety and Standards (FSS) Regulations, total soluble solids should not be less than 65.0 per cent in jam. Pineapple jam shall be manufactured from not less than 45 per cent, by weight, of prepared pineapple, exclusive of any added sugar. As laboratories cannot detect accurate percentage of fruit in jam, we opted for testing of total soluble solids in jam. TSS content in all brands was found to be above the prescribed legal limit. Highest TSS was found in Kissan (72.42 per cent), and the lowest in Dana (68.40 per cent). Basically, it is the fruit content and the quality of the fruit that determines the quality of the jam.

Yeast is a type of fungi. Yeast is commonly found on plants, grains, fruits and foods containing sugar. They are transferred from place to place by people,