Tuna sashimi

‘Sashimi-grade’ is not a regulated UK grade. Buy from a reputable fishmonger or supplier who confirms the tuna is intended to be eaten raw and has been handled for that use.

Keep the tuna chilled until you are ready, then use a clean, sharp knife to cut it across the grain into thin slices. Serve straight away; slicing against the grain makes each piece easier to bite.

Ponzu, soy sauce with a little wasabi, or a few drops of citrus and soy all work well. Dip each slice rather than leaving it to soak, which can overpower the tuna’s flavour and firm up its surface.

Only use frozen tuna that the supplier says is suitable for eating raw. Thaw it in the fridge, not at room temperature, and eat it promptly once thawed; freezing at home is not a reliable way to make unsuitable fish safe.

It is best eaten on the day you buy or prepare it. If you have leftovers, cover them and refrigerate promptly at 5°C or below, then use within 24 hours; discard them if they have been left out for more than two hours.

NHS advice is that sushi containing raw fish should use fish that has been frozen first. Tuna also counts towards the pregnancy limit: no more than two tuna steaks a week, or four medium cans.

Tuna sashimi has 24 g of protein per 100 g, compared with 19.9 g in salmon sashimi.