PR4 Penicillium Roqueforti (powdered format)
PR4 is used to make stronger and more pungent flavoured blue vein cheese such as Stilton and Gorgonzola. It has similar action to Blue Mould 3 (frozen liquid format). It produces stronger and more intense flavours from the breakdown of the fats and proteins. Ideally suited to blue cheese with requiring a stronger blue vein flavour. Liquid or powdered formats make no discernable difference; it comes down to personal preference of the cheesemaker.
Direct addition ¼ ‘drop’ or as little as a tip of a skewer (enough for 10 litres) of mould spores to approximately 100ml of warm cheese milk, stir in well and allow approximately 30 minutes for the spores to rehydrate before adding back to the remaining cheese milk. Ideally add the spores to the cheese milk at the same time the lactic starter cultures are added to the milk. Refreeze the powdered spores bottle after use.
Freeze-dried blue powder in resealable screw cap bottle
In freezer (-18°C)