Nappage

Nappage, jam glaze, pectin glaze or apricot glaze is a glazing technique used in pastry making. The glaze is used to cover fruit on a fruit tart or other baked goods, to make the fruit pieces shiny, prevent them from drying out, and to reduce oxidation (e.g., browning of cut fruit).^[1]

The active ingredient that gives nappage its glazing properties is pectin, a gelling agent naturally occurring in fruits.^[2] Traditionally, a nappage is made using an apricot jam diluted with water to form a transparent, slightly apricot-colored glaze, though redcurrant jelly may be used instead to accentuate the colour of red fruits.^[3] A neutral nappage (without the apricot flavour) may be made by mixing pure pectin with water and citric acid (or lemon juice) and heating to 45°C, which precipitates the gelling reaction, creating a base to which a diversity of flavours or colouring agents may be added. ^[2] Pectin NH (a variety of low methoxyl pectin) is typically used due to its thermoreversibility, which means that glazes made using it may be set and re-melted multiple times. This is useful in a commercial context where nappage may be made in large batches. ^[4]