To get the most racy and copious juice, let your limes soften - they are best when on the turn from green to yellow, and are soft enough that your thumb makes an impression. Rock-hard limes give a juice that is bitter. Best use for lime juice this week has been the day I tossed fried aubergines in a green salad dressed with lime, mint and coriander. A bowl full of hot, vibrant flavours that redeemed a day in which I'd consumed too much bland and fatty food. Practically, the snap of piquancy that lifts food from its doldrums is invariably added at the end of cooking.
Freshness can be elusive.
That squeeze of juice or dash of vinegar is something that generally only does its stuff when you use it as a last-minute flavour adjuster. Verjuice can be added at any point. I rubbed a small loin of pork with it the other day before roasting, then added some to the gravy at the end and the meat benefited doubly. A handful of seasonings that make your cooking sing, to lift its spirits, to give it that 'edge'. Sour, hot, aromatic.