A BOWL of lemons and limes sits on our kitchen table at home in readiness for summer lemonade and, of course, the occasional G&T.

But I get through even more just cooking. I cannot imagine cooking without a lemon to hand. Every morning I slice several into wedges for the day's work ahead. The clean sharpness of citrus is required even in moments where you would not imagine, yet were it to be omitted, you would notice its lack instantly.

Lemons, limes, oranges, blood oranges, grapefruit (both pink and yellow) and, at the right time of year, Seville oranges, can all be indispensable. In fact, citrus is the one ingredient where my normal scaffolding of "local" and "seasonal" comes tumbling down. You wont find Seville oranges after January, yet we all expect the rest of the wintry citrus family will be waiting for us, whenever we need.

And we do need them. A squeeze of lemon juice over a piece of fish frying in foaming butter is essential to lift the delicate flesh. The acidity also sharpens sauces or rich soups at the last moment. Lime zest and juice over honeyed mango or bubble gum-sweet strawberries, paradoxically, adds to their candy-like intenseness. A sliced lemon in the cavity of a roasting chicken with some garlic makes a luxuriously simple dinner; as do leaves and herbs dressed with olive oil and lemon juice. Summer's heat, the simplicity of the season's cooking and the freshness of citrus were undoubtedly made for each other.

Sliced sashimi of sea bream with lime and coriander

Recipe serves 4

4 fillets of very fresh sea bream, pin bones and scales removed by the fishmonger

1 lemon

1 lime

Small bunch of fresh coriander leaves

2 slim spring onions, root and outer layer trimmed and removed

olive oil to drizzle, a light, fruity one for preference

Method

1. Using a very fine grater or a microplane, grate the lime zest into a small bowl, taking care to scrape off the zest from the underside of the grater, where a lot can be left behind. Also, don't press too hard while zesting: you just want to remove the outer layer, not penetrate the white pith, as this can add a bitter flavour, covering the perfume of the lime. Once you have zested all over the outside surface, cut the lime in half and squeeze all the juice through a fine sieve over the lime zest. Set aside.

2. Now dice the lemon: with a small sharp knife, cut the top and base off, about a half to three quarters of a centimetre into the lemon, so you are removing the pointed ends from the top and bottom. This provides a stable base allowing the lemon to stand upright on its own. It should also allow you to see the beginnings of the inside flesh of the lemon; if necessary, cut away a little more so you can just see the flesh. Now, with the lemon standing upright on a chopping board, cut with a small knife from top to bottom, following the fruit's natural curve, to remove the skin revealing the flesh beneath, making sure you do not leave any of the pith behind as you go. Discard the skin. Once you have peeled the lemon, hold the lemon in one hand and your knife in the other: you can now cut in between the membranes which separate each segment of fruit, slicing towards the central spine of pith running the length, releasing the "fillets" of lemon from the skeleton of pith which holds the whole fruit together. Work over a small bowl to catch each piece of lemon as it is removed, and the juice. Once all the individual lemon pieces are cut out of the original whole, squeeze the pith in your hand, over the bowl. You should now have a small bowl containing the individual pieces of lemon plus some juice. Now cut each individual piece of lemon into six, creating something approximately like a small dice. Set aside. The lime zest and lemon can be prepared in advance, earlier in the day.

3. To finish and serve: place the first fillet of fish, skin side down, on a chopping board. Holding the tail end with one hand, cut from the tail to the head end, along the belly side, to remove any excess "fatty" white area, leaving a nicely shaped piece of fish which is all just flesh. Repeat with each fillet. Now, working one at a time, place each fillet on the chopping board and slice into very fine slivers with a sharp knife. As you finish cutting each fillet, lift it onto its own serving plate using the knife to act as a palette knife, scooping it up and placing it in the centre of the plate. Continue until all four are done.

4. Pick the smallest coriander leaves from the bunch and scatter over the fish and around the plate; think of these as salad leaves - at least 10 per plate. Now slice the spring onion into fine rounds and scatter these over the fish and around the plate.

5. Drizzle a little olive oil over each piece of fish and around the plate (about 1 dessertspoon per plate). With a teaspoon, drizzle the lime zest and juice over the fish and allow a little of the zest and juice to mingle with the olive oil on the plate. Now scatter the diced lemon flesh over the fish, about 5-6 pieces on the fish and a little more around each plate if you wish. Finally sprinkle on some sea salt flakes to each piece of fish and then serve at once.

Lime sorbet with mint and rum

Recipe serves 4

200g caster sugar

275ml water

8 limes, zested and juiced

2 lemons, zested and juiced

8 mint leaves plus a few small one reserved for garnishing

A couple of shots of good quality dark rum

Method

1. Combine the water and sugar in a small pan and warm to dissolve the sugar then bring to the boil and simmer for five minutes.

2. Remove from the heat to cool. Meanwhile, chop the mint leaves finely, ensuring to leave a few aside for garnishing the sorbet. Ensure the lemons and limes are zested and juiced.

3. Combine all of these prepared ingredients in a plastic tub and place in the freezer for several hours until frozen and set, stirring with a spatula or wooden spoon a couple of times as it sets and freezes.

4. To serve, chill four small bowls or glasses. Place a scoop of the sorbet in each, scatter over a couple of the small reserved mint leaves and then place in front of each person, with their own shot glass of rum to pour over their sorbet. Eat at once.

Geoffrey Smeddle is the chef patron of The Peat Inn, By St Andrews, Fife Ky15 5LH 01334 840206 www.thepeatinn.co.uk