Nama Sake and a Failed Cooler
On Thursday a distributor delivers 24 bottles of unpasteurized nama junmai ginjo (720 mL, 15.5% abv) in chilled cases. That night the walk-in cooler compressor fails; the alarm log shows the temperature reached 18 C between 22:00 and 08:00 before the unit was repaired. The bottles feel cold again by service. The first bottle opened on Friday hisses audibly and foams; a second bottle poured for a regular guest is faintly cloudy and shows a yeasty, slightly sour aroma. The guest says the sake is spoiled and asks for something else. At another table, guests ask for the same sake served hot, like real sake. Your invoice states returns are accepted within 48 hours only if the cold chain is documented.
1. Diagnose what has happened and state your serve-or-reject decision for the 24 bottles, with the checks you would run.
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Nama is unpasteurized, so live yeast and enzymes remain in the bottle. Ten hours at 18 C is a cold-chain breach. Residual sugar plus warmth restarts fermentation in the bottle, producing CO2 - the hiss and foam - plus ethanol and off-aromas; enzymes and proteins also drop out as haze. A little haze alone is normal in nama, and intentional in nigori, but haze plus pressure plus a yeasty, sour nose is refermentation, not style.
Decision: quarantine all 24 bottles.
- Check every bottle for bulging caps, weeping seals or leakage. Any bottle under pressure is a reject.
- Open one bottle from a different case, off the floor, and assess: a clean nama should be quiet on opening, smell of melon, pear, rice and faint lees, and taste clean with soft acidity.
- The hissing bottle is conclusive enough for the lot. Reject it.
Documentation: photograph the alarm log, the cooler repair report and the foaming bottle; email the distributor inside the 48-hour window, because the temperature log is exactly the cold-chain evidence the invoice requires. Ask for credit or replacement, not a discount on a lot you cannot sell. Pasteurized sake would have shrugged this off; nama is the one style where the cold chain is the product.
2. What do you say to the guest who sent it back, and what do you pour instead?
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At the table: apologise once, clearly, without a lecture. 'You are right, and I am sorry - that bottle has refermented after a cooler failure overnight. I am not serving it to anyone tonight.' Do not blame the distributor, do not recite the cooling log unless asked, and never suggest the guest is tasting it wrong.
Replace with a sake of the same style and register: a pasteurized junmai ginjo at 10-12 C in a wine glass gives the melon-and-rice profile and soft acidity they ordered, without the refermentation risk. If they want to stay with nama, offer one from a different, verified delivery - but only if you have opened and checked it yourself. Bring a small taste of the replacement first so they can approve it before the glass is filled.
Commercially: comp the sake and take it off the bill without being asked, and log the complaint against the lot number. Check whether the guest's companions are drinking the same sake; if they are, clear the table of it before the next course, not after. Notify the distributor the same day - a guest complaint plus a documented breach is a stronger claim than either alone.
3. The second table asks for the same sake served hot, 'like real sake'. What do you say and what do you do?
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Explain the tradition properly rather than refusing flatly. Hot sake is real: nurukan is roughly 40-45 C and atsukan 50-55 C, and warming has historically been used for fuller, rice-driven, pasteurised sake - for good reason, since heat rounds the alcohol and lifts rice and umami while blowing off delicate ginjo aromas.
That is exactly why it is the wrong call here. A nama junmai ginjo is unpasteurised; warming it toward 50 C accelerates the refermentation that has already damaged this lot and drives off the melon and pear aromatics the style is built on. Even a sound nama is served cool, 8-12 C, often in a wine glass to concentrate the nose.
Offer the alternative rather than the refusal: 'This one is unpasteurised and drinks best cool - may I bring it at 10 C in a wine glass? If you would like hot sake, I have a pasteurised junmai that is built for warming at 45 C.' Then pour a small taste of each so the table can compare. That turns a correction into a flight, which is usually what the guest wanted in the first place.