Effect of addition of traces of metals and ascorbic acid on the colour of glass-packed fruits.

The addition of traces of iron, either alone or in combination with other metals
like zinc, copper, lead and tin, to mang,o slices, packed in glass containers, results
in the darkening of the product soon after sterilization. In the case of mango pulp,
and also to some extent in the case of guava slices, traces of iron promote darkening.
There is no perceptible deleterious effect in the case of papaya, pear and pineapple.
Addition of ascorbic acid at 500 p.p.m. level to the syrup has a marked beneficial
effect in maintaining the bright yellow colour and strong, characteristic flavour of the
mango slices during long storage at ordinary temperatures.