MONITOR:SITTING IN O'Brien's Chop House in Lismore, Co Waterford, the most eye-catching main course was not on the menu at all – it was on the blackboard.
A whole plaice roasted on the bone, for two sharing. Bones, I love them. For all the mess and inconvenience involved in roasting whole fish on the bone, the flavour is so superior it is well worth the trouble.
Yet apparently we are not keen on fish bones, which is why most Irish menus sport fillets and darnes, with not a bone in sight. Things were not always thus. From our early years, the cod we had at home was always a cutlet, sliced through the backbone. Oven-baked, with anchovies and cream, the sticky gelatinous sauce came in part from the presence of bones. Roasting a whole turbot some years ago, my Italian friend Claudio spent a large part of the evening picking over the carcass in search of the flesh that lay hugging the bones.
Boneless fine-dining I understand, partly in sympathy with the presentation, because it is hard to do grand when you have a mass of bones. But ingenuity can triumph even here. In Arzak, a restaurant just outside San Sebastián in northern Spain, they sometimes dry and fry or bake fish bones, so they can be eaten with the dish. Slivers of elegant flavour, every gram of flavour extracted.
While we may struggle with the mess associated with fish bones, we know from sucking on roast chicken bones or tucking into a T-bone steak that there is flavour in there. Or do we? Bones contain high concentrations of albumen and collagen, which are converted into gelatine when combined with heat and water. Fish has a relatively high level of water (compared to meat) and as the bones are less dense, the whole process happens quickly.
Gelatine is a fixative and in its pure form is odourless and colourless. Combine it in a liquid however, and it increases viscosity and starts to interact with the tiny particles where flavours reside. This is not just true of the liquid gathering in the bottom of your roasting tin, but also the liquid attached to the flesh of the fish – and that attached to the bones, hence Claudio’s enthusiasm.
The same principle is at work when you roast a joint of meat. The gravy, or jus, is a combination of flavoured water from the meat combined with gelatine from the bones. This is one example of the umami flavour, which some say is the fifth taste – something meaty and savoury.
This principle is what stock-making is all about: bones, meat, some aromatics and vegetables simmered long and slow. But you quickly see that most of the flavour doesn’t come from the bones, although their presence is vital in delivering the final flavour.
Quickly roasting or grilling fish when it is on the bone has similar advantages. The trick is to capture the juices that are enhanced with the gelatine from the bones – and this is not always easy. Think of frying – there is rarely much in the way of juices in the pan as they are quickly burned off. But when roasting or grilling, you can end up with a sticky sauce emerging in front of your eyes.
What do you do with this watery liquid? Reduce to concentrate it a little and whisk in olive oil, cream or butter, and serve with the fish. Or wilt spinach or blanched leeks or broccoli cut small, so your sauce is partly a vegetable accompaniment – a sticky deliciousness that will surprise you.
harnold@irishtimes.com
