Scooping at the market stall
Dragon fruit looks dramatic and tastes mild, and that mildness works in a dog's favour: the flesh is mostly water, gently sweet, and easy on most stomachs in small amounts. If a stallholder is handing out spoonfuls, his taste should come from the same fresh-cut fruit you are sampling, scooped from well inside the skin. A market is a distracting place to feed a dog, so step aside from the crowd, let him take two or three spoonfuls calmly, and treat it as the novelty it is rather than standing there until half the fruit is gone.
What parts he gets — and what he does not
The flesh is his; the skin is not. That thick, leathery rind is tough to chew, tougher to digest, and it is the part that has been handled, displayed and possibly sprayed, so it goes in the bin even if he eyes it hopefully. The tiny black seeds scattered through the flesh need no picking out — in the quantities a dog eats, they pass through undigested and unnoticed, quite unlike the stones of plums or cherries that genuinely do need removing. Wash the outside of any fruit you bring home before cutting it, since market-stall produce travels through many hands before it reaches your chopping board.
Portioning a fruit this watery
A few spoonfuls at the stall, or a small handful of cubes over his food at home, is the right scale for a medium dog; a small dog needs only a cube or two. Dragon fruit's water and fibre are exactly what loosen stools when enthusiasm outruns portioning, so the first serving should be the smallest, with his next outing checked before you decide this fruit suits him. Because it is soft and mildly flavoured, it also works frozen in cubes on a warm day for a dog who enjoys a cold treat — but introduce it fresh first, so you know the fruit itself agrees with him before the frozen version joins his routine. At home, cubes cut in the morning keep their appeal in the fridge, while fruit carried around a warm market in a bag should be eaten there or thrown away, not saved for his evening bowl.
When to leave the fruit at the stall
Skip the taste if the cut fruit has been sitting uncovered in warm air for hours, if flies have been walking it, or if the flesh smells fermented rather than fresh — a dog's stomach is not the place to gamble on tired produce. Dogs whose weight or blood sugar is being managed with their vet should treat sweet fruits of any kind as rare events, and any dog who comes home from market day with vomiting or diarrhoea that does not settle by the next morning needs a vet's view rather than another new food to test.
Market-day tastes are easy to forget by the following week, which is how a dog gets 'introduced' to the same fruit four times. Adding dragon fruit to his feeding notes in KinsLe through Care Teams — tried at the market, tolerated well — means the next person walking him past that stall knows it is a known food for him, portion and all.