Roughly dice the strawberries. Weigh 800g pulp. Halve the limes and squeeze out the juice. Measure out 150 ml of juice. Mix the sugar, strawberries and lime juice well in a large saucepan. Bring to the boil, stirring constantly, and let it simmer for about 3 minutes. Fill jam into jars and close. Let cool upside down for approx. 5 minutes.