DOES TOASTING NUTS IMPROVE THEIR KEEPING CAPABILITIES?
Slightly, as well as enhancing the flavour. To toast most nuts you can spread them in a shallow ovenproof dish and place in a moderate oven for five to 10 minutes, untilbarely coloured. Cool before storing airtight. Shelled nuts also keep well if frozen in a sealed plastic bag (little thawing is needed), or for shorter periods in the fridge. Unshelled walnuts don't need refrigeration at all - you can store them in a cool place for up to a year.
IF I REPLACE LEMON JUICE WITH CITRIC ACID WHEN MAKING JAM, WHAT QUANTITIES SHOULD I USE?
Half a teaspoon of citric acid (or tartaric acid) is the equivalent of about 2 tablespoons of lemon juice, or the juice of 1 lemon. Citric acid rather than lemon juice is sometimes recommended in jam recipes because the acidity of lemon juice varies - and it's the correct proportion of acid, sugar and pectin that makes jam set. Not all jams require added lemon juice or citric acid, but marmalade usually does.
