Freezer temperature logs for UK food businesses

Why a freezer log is not a fridge log

Fridges and freezers both need temperatures written down, and Safer Food, Better Business for caterers treats them as part of the same opening habit. They are not the same control. A fridge is trying to keep food cold enough that bacteria grow slowly, at 8°C or below in law in England, Wales and Northern Ireland, and ideally at 5°C or below in practice. A freezer is trying to keep food frozen hard, so the clock on bacterial growth is effectively stopped for as long as the food stays frozen. The fridge temperature log guide is the chilled record. Use it for fridges, chilled walk-ins and display chillers. Use this page for freezers and frozen cold stores. A site that writes one column called "cold" and ticks it has neither record.

Freezing does not kill the bacteria already in the food, and it does not make spoiled food good. That is why a soft delivery is rejected rather than "frozen again", and why thawing is a planned step. The thawing guide starts when you decide to defrost. The log's job is to show that, until that decision, the food stayed hard. If the log is a row of identical −18s written on Friday for the week, it does not show that.

A chilled walk-in is sometimes called a cold store on a drawing. If it is meant to hold food at fridge temperatures, it belongs on the fridge log, with fridge limits. If it is meant to hold food frozen, it belongs here. Name the rooms the way the team talks about them, and put the set point on the log header so a new supervisor does not apply 5°C to a freezer or −18°C to a chill room.

Scottish businesses should follow Food Standards Scotland and CookSafe. The habit is the same: a number you actually saw, a person, a time, and an action when the food is not hard.

The set point you write in the method

The Food Standards Agency's working temperature for frozen food is −18°C or colder. Safer Food, Better Business tells caterers to keep frozen food at that sort of temperature and to check that it is frozen hard. Write −18°C or colder into the safe method as the standard for storage freezers, and write the set point you actually dial in if you run colder, often −20°C to −22°C, so the cabinet has a margin when the door is opened for a delivery. The set point and the legal-or-guidance limit are not rivals. The set point is how you aim. The limit is how you decide the reading is a problem.

Quick-frozen foodstuffs have their own rules. The Quick-frozen Foodstuffs Regulations, in England and in the equivalent rules elsewhere in the UK, require quick-frozen food to be kept at −18°C or colder, with only brief, limited upward fluctuations allowed during transport and in retail display cabinets. A catering storage freezer is not a retail display cabinet. Do not borrow a shop-display tolerance to justify a kitchen freezer that lives at −12°C. Ice cream cabinets and other display freezers need a limit written for that unit. If the manufacturer and the product say the cabinet must hold −18°C, that is the limit you record against. "It is only ice cream" is not a higher set point.

Put the limit on the log, next to the unit name, so the person checking does not have to remember it. A chest freezer in the dry store, a walk-in freezer, and a small upright by the pastry section can all be on one sheet if each has its own line. They should not share a single reading. One warm chest and one healthy walk-in are two facts. Averaging them is how you hide the chest.

Alarms, if you have them, need a set point that means something. An alarm that only sounds at −5°C will let a freezer drift for hours while food softens. Set the alarm closer to the limit you care about, test it, and write down what staff do when it sounds. An alarm nobody is trained to answer is a noise. The wireless sensor guide is about continuous monitoring. It does not remove the need for a decision when the number is wrong. A sensor history is a stronger log only if someone acts on it.

Which units belong on the sheet

Every freezer that holds food you will serve belongs on the log. That includes the walk-in, the upright, the chest, the undercounter if you freeze portions in it, and the ice cream or frozen-dessert cabinet. It includes a freezer in a shed or a cellar if that is where the chips live. It does not include a broken cabinet you have already taken out of use, as long as it is labelled out of use, switched off or isolated, and empty of food. A "spare" freezer that still has a bag of prawns in it is in use. Log it or empty it.

Name units the way staff name them. "Pastry chest" is better than "asset 14" if the engineer is the only person who says asset 14. If you add a freezer, add a line the same day, before food goes in. New equipment is a common gap: the kitchen is proud of the cabinet and the log still has last year's three units.

Blast chillers and blast freezers are process equipment, not storage. If you use a blast freezer to freeze food down, the record of that cycle is a production record: what you froze, when it reached a frozen state, and where it went afterwards. Do not pretend a blast freezer's short cycle is the daily storage log for the walk-in. Once the food is in the storage freezer, the storage log takes over. If the blast unit is also used as overnight storage, say so, and check it on the same round as the other freezers. Dual use is where food is forgotten behind a tray.

How often to record

SFBB routines expect fridges and freezers to be checked at the start of the day, before you rely on them, and at least once later on days you are open. Write the actual reading, the time, and the name of the person who looked. A tick, a sticker, or a column of identical figures is not a reading. Real cabinets move. A log with honest variation, including a −16°C that was rechecked after the door was shut, is more credible than a perfect sheet.

Check before prep, not when someone remembers at the end of the night. If you are closed, do not invent a trading-day line. If you open for a function on a day you usually shut, that day needs a check too. A walk-in that holds food over a weekend still needs a Monday opening check before you decide the food is fine. The weekend is not invisible. If nobody was on site, the Monday reading and a look at whether food is still hard are the evidence you have. Do not write Saturday and Sunday figures you did not take. If you have a sensor, the weekend trace can fill that gap, and a person still signs that they looked at it.

Extra checks belong in the method, not in people's heads. Do one when a unit has alarmed, after a power cut, after a delivery that left the door open, after a defrost that seemed long, and before you put a large warm-from-cooking freeze-down into a storage cabinet. The later check on a normal day can be at the start of evening service or at close. Pick a time the rota can keep. A time nobody is in the building will be filled in from memory.

Supervisors sample the sheet at least weekly: missing names, weekends that appeared from nowhere, readings that never change, and actions that were never closed. The 4-weekly review looks at repeats. If the chest by the back door is always warmer on Saturdays, the action might be a door closer, a limit on how long the door stays open for the chip delivery, or moving that food into the walk-in. The review writes the change. Another month of the same −14°C with no action is a managed failure.

Built-in displays and probes

The figure on the cabinet door is an air temperature at a sensor the manufacturer placed. It is the right thing to write down if your safe method says you record the display, and it is fast. It is not the temperature of the prawns by the door, and it is not proof the food is hard. During a defrost cycle the air can rise sharply while the food, which has thermal mass, stays frozen. If you record a warm display in the middle of defrost and throw away a freezer full of hard food, you have misunderstood the tool. If you ignore a warm display every day because "it always does that", you will miss the day the compressor has failed.

The way through is to write what you see, note "defrost" if you know that is what it is, and confirm the food. Press a case. Look for soft corners, free liquid, or a heavy frost collapse. Probe between packs, or into a dummy pack you keep in the warm spot for this purpose, if you need a number for the food. Do not stab a probe through the packaging of food you intend to keep, unless that pack will be used immediately and the hole is not a contamination path you cannot close. Between-pack readings are the usual check. An infrared gun reads a surface and will mislead on shiny film and on food that has just come from a colder room. It can tell you a pallet is obviously warm. It is not the instrument your method relies on. The delivery version of this point is in the delivery temperature guide. The same probe habits apply once the food is yours.

The probe itself has to be honest. Ice water should read close to 0°C and boiling water close to 100°C, on the schedule in your method, with the difference you will accept written down. Many kitchens use about ±1°C. The probe calibration guide is the method, and the probe calibration record is a simple sheet. A probe that reads −22°C in a cabinet which is only −15°C will make every corrective action late. Do not move a probe from raw thawing meat to a freezer check without cleaning and disinfecting it. Freezers are not a separate planet from cross-contamination.

Where you probe matters as much as whether you probe. The warm spot in a freezer is often near the door, at the front, or anywhere air from the kitchen rushes in. The cold spot is near the evaporator, which can be cold enough to confuse you if you only ever measure there. Map the cabinet once, the way you map a fridge, on a settled day. Put any dummy pack or sensor in the warm spot you are prepared to defend, not in the coldest corner where it flatters the unit. Do not block the fan with the dummy pack. Air has to move or the map will change under you.

If a sensor and a display disagree by more than a small margin, write both, say which one you use for the accept-or-act decision, and get the other checked. Silent preference for the colder number is how logs lie. Staff should know which figure they record on an ordinary day so two people do not log two different instruments without saying so.

What a credible line looks like

A useful line has the date, the unit, the time, the reading, and the name. If the reading is within the limit and the food you glanced at is hard, the line can stop. You do not need a comment for a healthy freezer. Comments are for exceptions: door was open for a delivery, rechecked twenty minutes later, food still hard, no food thrown away. Or: display −9°C, chips at the door soft, thrown away, hard stock moved to the upright, engineer called.

Keep the history. Officers look back over weeks. A sheet that starts the morning of the visit is not a system. If you correct a mistake, leave the original visible and note the correction. Do not overwrite. Wet paper, a pencil that has smeared, and a photo of a sheet that lives on someone's phone are fragile. The working copy should be findable at the unit or on the daily diary. A digital log is fine if it shows the same facts and does not let someone change yesterday without a trace. The digital SFBB diary guide is the wider question of paper versus screen. Either can be honest.

The freezer temperature log is a printable layout for the columns. It is a form, not a control. The control is the person who opens the door, reads the figure, looks at the food, and writes before they start prep. If the form runs out, a dated line in the diary with the same facts is acceptable for that day. Order more forms. Do not stop checking because the pad ended.

Defrost, ice and doors

Automatic defrost is normal. Note it when you catch it, recheck when the cycle should have finished, and do not let "it was on defrost" become the explanation for every warm reading including the ones at 4pm when no defrost is scheduled. If you do not know the defrost times, ask the engineer and write them on the log header. A reading you cannot interpret is a reading you cannot defend.

Ice build-up is a maintenance problem and a temperature problem. A door that does not seal, a heater that has failed, or a cabinet packed so tight that air cannot move will ice up. Ice reduces space, hides food, and can wedge a door open. Clear ice on the schedule the manufacturer expects, and move food to another freezer first so it does not sit out while you chip. Do not attack an evaporator with a knife. Punctured lines are an expensive way to lose a cabinet, and metal shards are a foreign-body risk. If food has to come out for a long defrost, the log should say where it went and that it was still hard when it moved.

The door is the control staff actually operate. A walk-in left ajar by a delivery, a chest with a case stopping the lid, or a strip curtain tied up will warm the air quickly. The food may still be hard if the lapse was short. Write the reading, shut the door, recheck, and look at the food nearest the opening. Train people to shut the door even when they are "only grabbing chips". A hook to keep it open during a twenty-minute delivery is a choice to heat the freezer. Unload in trips and shut it between them.

When the reading is too warm

An out-of-range reading is not a failed inspection. Ignoring it is. Start with what the food is doing, not with a speech about the number.

1. Write the reading you see, the time, and your name. Do not round a −12°C into a −18°C.
2. Shut the door if it was open. If you know the unit is in a defrost cycle, note that and recheck when the cycle should have ended.
3. Look at the food. Is it frozen hard, including at the door, or soft, wet, or clumped with refrozen ice crystals?
4. If the air is warm and the food is still hard, move it to another freezer that is cold enough if this cabinet is not recovering. Recheck and write the second reading.
5. If food has thawed, decide. Do not refreeze raw food that has thawed. Follow the thawed-food rules below, and record what you threw away or cooked.
6. If the cabinet does not return to its limit, label it out of use, call the engineer, and keep food out of it. Write the recheck that shows it is back, or that it is still out of use.

That sequence is a corrective action: what was wrong, what you did, what you will do next. The corrective action guide is the format, and the corrective action record is a paper version when the margin of the log is too small. "Engineer called" with no note of the food is half a record. The officer's question is whether anyone ate the soft prawns.

Do not use a freezer as an emergency dump for warm chilled food unless your method allows a short, controlled step and you protect ready-to-eat food from raw food while you do it. A freezer full of hot stock will warm the frozen food already in there and will not cool the stock quickly enough to be a proper chill. The cooling guide is the route for hot food. The freezer log should not be full of heroic rescues.

Power cuts and food that has softened

If the power fails, keep freezer doors shut. Opening them to "check everything" dumps the cold air you still have. Note the time you noticed the failure. When power returns, or when you can move food, check each unit. Food that is still frozen hard can go to a working freezer. Write the move.

Food that has started to thaw needs a judgement you can explain. Soft corners on an otherwise hard block, found quickly, with the core still solid, are different from bags sitting in liquid. If you cannot tell how long food has been warm, and it is high-risk, throw it away. Do not guess a convenient time so that the four-hour thinking you use for chilled food makes the decision look neat. The fridge guide describes that four-hour approach for food left out of refrigeration. It is not a licence to invent a timeline for a freezer that failed overnight when nobody was there.

Do not refreeze raw meat, poultry, fish or other raw foods that have fully thawed. Refreezing does not undo the time they spent growing bacteria, and it damages the food. If the food has only just thawed, is still cold, smells and looks normal, and your method says you may cook it thoroughly straight away, you can cook it and then cool or freeze the cooked dish if that dish is one you are allowed to freeze. Write that you cooked it because the freezer failed. Ready-to-eat frozen food that has thawed is the stricter case. Melted ice cream, thawed cooked prawns, thawed cheesecake and similar foods are not made safe by refreezing, and they are usually thrown away once they have softened and warmed. When in doubt, throw it away and record the loss. A credit from the insurer or a bad week of waste is cheaper than serving it.

Large ice crystals, wet packaging, and blocks that have refrozen into a single lump are signs food thawed and was frozen again before you noticed. Treat that food as unsafe to trust. You do not know how long it was warm. Reject it if it has just arrived, which is a delivery decision. If it is already in your freezer, throw it away and look at why the cabinet warmed. Do not serve it because the display is cold now.

Walk-in freezers and ice cream cabinets

A walk-in freezer is a room with a set point. People leave the door open, store cardboard, and put today's delivery in front of last month's stock. The log still needs a reading, and the layout still needs rules: food off the floor, door shut, fan clear, older stock reachable. Cardboard and empty crates do not belong in there. A dark walk-in with a broken lamp is where soft food is missed. Replace the lamp.

Check the food at the door as well as the display in the lobby. The lobby air and the food temperature are not the same, especially if a person has been picking in there for ten minutes. If the walk-in has an internal thermometer and an external display, say which one you log. If they drift apart, maintenance is due. Strip curtains should hang closed. Tied-up curtains are an open door.

Ice cream and dessert freezers are opened constantly and are often in a warm shop or server station. Give them their own line. A storage walk-in at −20°C does not prove the ice cream cabinet is cold. Staff should know the product limit and what to do with tubs that have melted and refrozen, which is to throw them away. Lids stay on. A cabinet used as a general freezer for chicken because "there was space" will contaminate a ready-to-eat dessert freezer and will usually run too warm for both jobs. Do not mix them.

Chest freezers are easy to ignore because the lid hides the food. They stratify: the top can be warmer than the bottom. Do not store high-risk food in a chest that ices over and is opened with a shovel. Rotate when you add a delivery, or the bottom becomes a graveyard of anonymous bags. If you cannot identify it, you should not serve it.

Sensors next to the written decision

A continuous sensor is useful because it sees the weekend and the hour after midnight when nobody is there. Place it in the warm spot, away from the door draft and away from the evaporator, and name it after the unit staff use. Check that the alarm reaches a person who will act, not a closed inbox. On Monday, someone looks at the trace, writes or signs that they looked, and records any excursion the same way they would record a bad manual reading. A graph nobody reviews is not a log.

Sensors fail, batteries die, and Wi-Fi drops. Your method should say what you do when the sensor is silent: go back to a manual display reading and a look at the food, until the sensor is trusted again. Do not invent a trace. The manual round is the backup, and it should be practised, not discovered during a failure. Calibration or a comparison with a probed dummy pack belongs on a schedule, so you know the sensor and the food are still related.

What environmental health officers check

Officers are asking whether frozen food stayed under control on ordinary days, and whether a warm cabinet produced a decision rather than a tidied sheet. They open the freezer. They compare it with the log.

• Every freezer that holds food is on the record, under a name staff recognise, with the limit written down.
• Readings are numbers, taken at the frequency in your method, with a time and a person. Ticks and copied columns are not readings.
• Days you were open are not blank. Days you were closed are not invented.
• A warm reading has a recheck, a note of whether food was hard or soft, and what happened to the food. The engineer story matches the diary.
• Food in the cabinet is frozen hard, labelled, and not a solid lump of refrozen melt. Soft product is not being served.
• The display, a probe, and any sensor are not contradictory without a written explanation.
• The probe used for checks has itself been checked. Staff can find that record.
• Doors seal. Ice is not welding the door open. Fans are not buried in stock.

They may ask what you would do if the walk-in failed on a Saturday night. The answer should match the method: doors shut, food assessed, hard food moved, thawed raw food not refrozen, ready-to-eat thawed food thrown away, the event written down. The inspection checklist is the rest of the visit. The freezer log is one of the faster ways they judge whether records are lived.

Worked example

A restaurant has a walk-in freezer set at −20°C, an upright by the pastry section, and an ice cream cabinet at the servery. The safe method says each is logged at opening and before evening service, display temperature written as seen, food glanced at for hardness, and a between-pack probe used if the display is warmer than −18°C or if anything looks soft. The ice cream cabinet has its own limit of −18°C. The paper freezer log is on a clipboard outside the walk-in.

On a Thursday the opener finds the walk-in display at −9°C. They write −9, not −18. Chips nearest the door have soft corners and a wet patch in the bottom of the box. A case of chicken at the back is still hard. They shut the door, wait half an hour, and read −11°C. The cabinet is not recovering. Hard chicken and the hard stock behind it are moved into the upright, which is at −21°C. The soft chips are thrown away because they have thawed and nobody knows how long the door or the compressor has been failing. The walk-in is labelled "do not use". The diary says: "Walk-in −9°C at 08:10, −11°C at 08:40. Door chips soft, binned. Hard food moved to pastry upright. Engineer called 08:50. Walk-in out of use. Priya." The ice cream cabinet is −19°C and is left in service. It is not used as a substitute store for the chicken.

The engineer replaces a torn door seal that afternoon. Priya rechecks: display −21°C, between-pack probe at the door −19°C, food hard. Both numbers go on the log, and the walk-in is signed back into use. She does not move the chicken back until the cabinet has held its temperature. At the 4-weekly review the owner writes that the alarm, which had been set at −8°C, is moved to −16°C so the next drift is seen before food softens, and that Saturday deliveries shut the walk-in between trips. The thrown chips are on the waste note. That is a freezer record an officer can follow from the bad number to the food.

Common mistakes

• Writing −18°C because that is the target, not because that is what the display showed.
• One reading for three freezers, or a freezer missing from the sheet because it is "only ice cream".
• Ignoring a warm display every morning because defrost happens at that time, without ever rechecking.
• Refreezing raw food that has thawed, or serving ice cream that melted and set again.
• Opening a failed freezer repeatedly to look, instead of keeping the door shut until you can move hard food.
• Probing through packaging you will then store with a hole in it.
• A probe that has never been checked in ice water.
• Cardboard, blocked fans, and a door that does not seal.
• Sensor graphs that nobody signs, and no manual check when the sensor is offline.
• Backfilling a week of readings after an officer books a visit.
• Using the freezer log for a chilled walk-in, or the fridge limit for a frozen store.

Where this comes from

Frozen storage practice in this guide follows the Food Standards Agency's chilling guidance and the chilling safe methods in Safer Food, Better Business for caterers, which expect frozen food to be kept at about −18°C or colder and checked. Temperature control duties for food that must not be kept at ambient temperatures sit in the food hygiene regulations for England, Wales and Northern Ireland, underpinned by assimilated Regulation (EC) No 852/2004. Quick-frozen products are covered by the Quick-frozen Foodstuffs Regulations and the equivalent rules in the rest of the UK. What officers look at more widely is in the Agency's food safety inspections and enforcement guidance. Scottish businesses should follow Food Standards Scotland and CookSafe. Write the units, the limits, and the action when food goes soft into your own safe method, and keep the readings you actually took.