Use a short-bladed, sharp knife to score four vertical lines on the skin of each pomegranate. Cut the top and bottom off each fruit. With the help of the knife (and a little bit of determination) divide each one into four segments. Remove the red seeds and put them in a bowl, carefully discarding the white/beige parts. Set aside a teaspoon of seeds per glass (Martini cocktail glasses are ideal) to use for decoration. Tip the others – a few at a time – into a small, fine-meshed strainer held over a bowl, and crush them with a spoon the extract the juice. When you have completed this operation, taste the juice (just a little!); if it seems sour (this will depend on the type of pomegranate) add a small amount of sugar, stirring thoroughly. Cover and keep in the fridge.
Prepare the glasses (Martini cocktail glasses are ideal), preferably kept until then in the fridge or freezer, by putting a teaspoon of pomegranate seeds into each one.
Pour the well chilled Spumante into a jug, and add the pomegranate juice, stirring delicately. Then serve immediately!