Eight hours in a warm tank in July
Mid-July. A distributor loads 30 live トラフグ (about 1.3 kg each) at 06:00 into a 200 L tank on a truck for an eight-hour run to an inland city. Loading water is 18 °C; by hour five it is 24 °C. A generator fault stops the aerator for about 40 minutes, and six fish die before arrival at 18:00. The receiving chef holds the fugu licence. He plans to 活け〆 the 24 survivors, ice the six dead fish, and process the dead ones at 11:00 the next morning, because 「they were alive this morning and the fridge will hold them」. He also notes that two survivors have swollen bellies and reddened vents, and that the tank water smells sharply of ammonia. The banquet for 40 guests is at noon tomorrow. The kitchen has a 6 °C refrigerator, a −18 °C freezer, and one working ice machine.
1. What is your decision on the six dead fish, and why?
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They should not be processed for raw service. Once a fish dies unassisted, blood is not drained, autolysis starts immediately, and the cause of death is unverified - in this load the likely causes are heat, oxygen depletion and ammonia, but you cannot rule out a fish that was already compromised at loading. A fugu licence authorises you to remove toxic organs from fish you can vouch for; it does not let you convert an uncontrolled death into sashimi.
The 6 °C refrigerator will slow but not reverse that, and an 11:00 processing time is 17 hours after death. For a banquet, the downside is not merely quality: if a guest becomes ill, every deviation in the chain becomes evidence. Discard the six through the documented waste route, record the loss, and notify the supplier, since the transport failure is theirs to answer.
If the kitchen wants a heated dish, that does not fix it either - cooking does not resolve an unknown death and spoilage history.
2. The survivors: what do the water temperature, the ammonia smell and the two abnormal fish tell you, and what do you do tonight?
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18 °C rising to 24 °C with a 40-minute aeration stop in a 200 L tank holding roughly 39 kg of fish is a severe load: oxygen drops, ammonia climbs, and six decomposing bodies add to it. The sharp ammonia smell is the measurable sign; the swollen bellies and red vents indicate stressed or damaged fish, not normal stock.
Tonight: stop feeding, reduce density, change water with clean cooled seawater and restore aeration, then 活け〆 the survivors promptly rather than holding them in worsening water - ikejime with a proper 血抜き, chilled quickly in ice water, then stored at 0–4 °C, single layer, drained, in a covered container.
Separate the two abnormal fish and do not use them for raw service; the cost of two fish is trivial against the banquet. Record tank temperature, the aeration failure and the actions taken with times.
3. It is 19:00 and the banquet is at noon. Set out a storage and preparation timeline for the 24 survivors.
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Twenty-four fish at 1.3 kg is roughly 30 kg whole, ample for 40 covers, so there is no need to press the schedule. Tonight: 活け〆 and 血抜き all 24, chill in ice water, then hold at 0–4 °C in a single layer, wrapped and separated from ready-to-eat food. Label with species, date, time and handler.
Tomorrow: begin 身欠き no earlier than needed, with dedicated knives and boards, toxic organs into the labelled lockable container as they come out, and the flesh moved straight to cold holding. Keep the frames and skin in a separate container from finished sashimi.
The −18 °C freezer is not a solution: it is not cold enough for the usual parasite-inactivation standard, freezing does not reduce tetrodotoxin, and freeze-thaw ruins the texture you are charging for. If any survivor looks doubtful in the morning, buy in pre-processed product from a licensed supplier rather than serving a fish you are arguing with.