Bottarga is salt cured fish roe. The eggs are kept in the sacks and are cured whole. The sacks have to be intact as much as possible, otherwise you will run into a number of problems. Traditionally it is made with grey mullet or tuna roe but can be made with any roe – the smaller the eggs the better as larger eggs won’t hold their shape due to the large water loss.
I have made bottarga a few times now and have used trevally roe as the egg sacks are quite large and the eggs are very small. Traditionally it is grated over seafood pasta dishes; personally I put it on lots of things – pasta, omelettes and a personal favourite – sliced and drizzled with olive oil. The curing process concentrates the flavour, so a little bit goes a long way. It’s best used as a finishing condiment rather than adding during the cooking process as cooking the bottarga will alter the flavour.
Whole fish roe/egg sacks (small eggs are best)
When making bottarga use the freshest fish roe possible and ensure that the membrane surrounding the eggs is intact.
Tidy up the fish roe by discarding any hanging membrane pieces, blood clots etc. Pat down the roe with paper towel and place into a large, non metallic bowl.
Make up a 1% salt brine solution (10 grams salt in 1L of cold water) and soak the roe overnight in the brine solution. The brine will change colour – don’t be alarmed!
Remove the roe from the brine and pat dry with paper towel.
Coat the roe with olive oil for 3-4 hours, turning once to apply a second coat of olive oil.
Lay paper towel across a large flat tray and liberally sprinkle salt to cover the paper towel. Lay the roe on the salt. If you have the room, try and ensure that the roe does not touch.
Cover the top of the roe with salt and place in the refrigerator for 2-3 days. The time will vary depending on the size of the roe.
Twice a day completely replace the paper towel and salt.
After 2-3 days the roe will be noticeably firmer. If it is hard it’s gone too far and will be very salty. Rinse of any excess salt and pat dry with paper towel. Lightly brush with olive oil again.
With a sharp object, such as a skewer, carefully make some holes at the top of the roe (try not to tear the roe sacks). Thread twine and hang in a cool dry place or at the back of the refrigerator for around 10-14 days. Again, the time will depend on the size of your roe. Sometimes mine go over or under this time.
The roe will be quite firm to the touch and you should be able to slice it. Once bottarga is ready it can be thinly sliced or grated straight over a dish.