Compare prices for fresh limes across Edmonton retailers.
The common supermarket lime is the seedless Persian (Tahiti) lime, and it is non-climacteric: it is picked mature and does not ripen, sweeten, or grow juicier after harvest, so the fruit in the bin is as good as it will ever be and choosing well is the whole task — the same whether you need it tonight or later in the week. Pick limes that feel heavy for their size, which is the single best clue to juiciness because a light lime has dried out inside, and that are firm with only the slightest give and wrapped in a smooth, glossy, thin skin; a thick, coarse, hard rind hides more pith and yields less juice. Colour is a freshness signal rather than a ripeness one: a fresh lime is deep, even green, and the yellowing that develops as a lime ages means it is older and milder, not better — a fully yellow lime has lost acidity and is usually beginning to dry out. Small tan or brown surface marks are cosmetic wind-scarring and harmless; pass instead on any lime with soft or sunken spots, a dull shrivelled skin, or fruit that feels light and hollow.
Because a lime does not improve on the counter, one is ready to use the moment you buy it, and the only real decision is how long you need it to keep. For limes you will use within a few days, a bowl at room temperature is fine and makes them slightly easier to juice. To hold them through the week and beyond, refrigerate: loose in the crisper they keep one to two weeks, and in a bag or container that slows moisture loss they hold up to about four weeks, far longer than at room temperature. If a lime has started to firm up or its skin is hardening, roll it firmly under your palm or warm it briefly before juicing to free more of the juice still inside.
A lime is past its prime when the skin hardens, wrinkles, or shrivels and the fruit feels light and dry, all signs it has lost its juice, or when you find soft sunken patches, weeping or stickiness, a fermented smell, or white, green, or blue mould; a mouldy lime should be thrown out rather than salvaged, since the rot runs through the rind into the flesh. A lime that has turned yellow and gone slightly soft but still smells clean is milder and less juicy but still usable. In an Edmonton winter, treat limes as the cold-sensitive imported citrus they are: a lime left in a sub-zero vehicle will freeze and thaw into a dry, collapsed fruit, so carry them indoors promptly, and over long cold storage watch for the small sunken pits and brown staining of chilling injury, which shortens their life.
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