How to make sushi and raw fish dishes safely in Australia: parasite freezing, sushi rice acidification to pH 4.6, time-temperature control and RTE handling.
Making sushi and raw fish dishes safely comes down to three controls: source fish suitable to eat raw, freeze it to destroy parasites (FSANZ advises at least 7 days frozen), and manage the rice either by acidifying it to a pH of 4.6 or less or by keeping it under strict time-temperature control. Handle everything as ready-to-eat, and always confirm the exact rules with your state or territory food regulator and local council. Key takeaways: Raw fish carries two distinct hazards: parasites (controlled by freezing) and bacteria such as Listeria and Vibrio (controlled by sourcing, cold chain and hygiene). Freezing does not kill bacteria.. FSANZ advises freezing raw fish for at least 7 days to kill parasites; commercial parasite-destruction schedules commonly referenced internationally are -20 degrees C for 7 days or -35 degrees C for about 15 hours.. Sushi rice is generally safest when acidified to a final pH of 4.6 or less, verified with a calibrated pH meter, which lets it be held at room temperature; unacidified rice is a potentially hazardous food.. In NSW, acidified sushi may be displayed above refrigeration (up to 25 degrees C) for a maximum of about 4 hours only if the rice is acidified to pH 4.6 or less, the pH is recorded and display time is monitored.. Vulnerable people, including pregnant women, the elderly and the ill, are advised by FSANZ not to eat raw or cold-smoked fish, largely because of Listeria.. Freezing to destroy parasites in raw fish: Guidance/schedule, Temperature, Time. FSANZ guidance — Frozen — At least 7 days. Commercial schedule — -20°C or below — 7 days. Commercial schedule — -35°C or below — About 15 hours (held solid). The two hazards you are actually managing Raw and lightly-cured fish dishes carry two very different risks, and effective control means addressing both separately. The first is parasites, such as Anisakis roundworms and certain tapeworms found in wild-caught fish. These are physically destroyed by freezing but are not affected by acidifying rice or by chilling. The second is bacteria, including Listeria monocytogenes, Vibrio species, Salmonella and Staphylococcus aureus. Bacteria are controlled by buying quality product, keeping an unbroken cold chain, preventing cross-contamination and good personal hygiene. Critically, FSANZ notes that freezing will not kill potentially harmful bacteria, so a frozen fish is not automatically a safe one. Because sushi and sashimi receive no cook step to destroy pathogens, every component is effectively ready-to-eat (RTE). That reframes the whole task: you are relying on preventive controls, not a final kill step. Parasites: controlled by freezing, not by chilling or acidification. Bacteria: controlled by sourcing, cold chain, hygiene and no cross-contamination. No cook step means no safety margin to fall back on. Sourcing fish suitable to eat raw The safest starting point is fish that has been commercially prepared and marketed specifically to be eaten raw. FSANZ advises buying raw fish labelled as sashimi grade from a reputable supplier. "Sashimi grade" is a commercial and quality descriptor rather than a defined legal grade in the Food Standards Code, so it is not a guarantee on its own; it signals that the supplier intends the product for raw consumption and has generally handled it accordingly. When buying, ask your supplier two direct questions: has the fish been frozen to a parasite-destruction schedule, and is it intended to be eaten raw? Keep the supplier specification or invoice as evidence of approved supplier and product suitability. Fish should be received cold (at or below 5 degrees C), smell clean and briny, and show firm flesh and clear eyes. Reject anything with an off odour, dull or sunken eyes, or a broken cold chain on delivery. Prefer product labelled sashimi grade and intended for raw consumption. Confirm the supplier has frozen it to a parasite-destruction schedule. Keep invoices and supplier specifications as approved-supplier records. Receive at 5 degrees C or below and reject product that fails a sensory check. Freezing to destroy parasites Freezing is the recognised control for parasites in fish that will be eaten raw or only lightly cured. FSANZ advises that freezing raw fish for at least 7 days will kill parasites that may be present. Internationally, the widely referenced commercial parasite-destruction schedules (for example in the US FDA Fish and Fishery Products guidance, which many processors align to) are freezing at -20 degrees C or below for 7 days, or -35 degrees C or below until solid and then held at -35 degrees C for about 15 hours. Ordinary domestic freezers often do not reach or hold these temperatures reliably, which is another reason to rely on commercially frozen product. Some products are treated differently in international guidance - for example certain large tuna species and some farmed fish raised on formulated feed - but these exemptions are technical and species-specific. Do not assume an exemption applies; confirm suitability with your supplier and regulator. After freezing, thaw fish in the fridge in a sealed container on the bottom shelf so juices cannot drip onto other food, and use it within about 2 days once thawed. Requirements can vary by jurisdiction, so verify the approach that applies to your business with your state or territory food authority. FSANZ: freeze raw fish for at least 7 days to kill parasites. Common commercial schedules: -20 degrees C for 7 days, or -35 degrees C for around 15 hours. Domestic freezers may not hold these temperatures - use commercially frozen product. Thaw in the fridge, sealed, on the bottom shelf, and use within about 2 days. Sushi rice: acidification versus time-temperature control Cooked rice is a classic vehicle for Bacillus cereus, which can survive cooking as spores and produce toxin if the rice sits in the temperature danger zone. There are two accepted ways to manage sushi rice. The first is acidification. Sushi rice acidified with a vinegar mix to a final pH of 4.6 or less can generally be treated as non-hazardous and held at room temperature, because most pathogens of concern cannot grow or produce toxin at or below pH 4.6. This requires a validated recipe and routine checking with a calibrated pH meter (test strips are usually not precise enough for a critical control point). NSW Food Authority preparation guidance indicates acidified rice can be held at room temperature for a limited period on the day it is made, and rice should be rejected if its pH is above 4.6. The second is time-temperature control. If rice is not acidified, it is a potentially hazardous food and must be kept at or below 5 degrees C or at or above 60 degrees C, or managed under the 2-hour/4-hour rule. Whichever method you choose, write it into your procedures and keep the pH or temperature records. Acidify to a final pH of 4.6 or less using a validated recipe. Check pH with a calibrated pH meter, not indicator strips. Reject rice if the pH is above 4.6, and record every check. Non-acidified rice must be kept at 5 degrees C or below, or 60 degrees C or above. Display, temperature and the NSW room-temperature concession Raw fish, cooked seafood, cooked rice that has not been acidified, and finished sushi are potentially hazardous foods. When they sit between 5 degrees C and 60 degrees C, refrigerated display and service is the safest default. NSW illustrates how a room-temperature concession works in practice. The NSW Food Authority permits retail sushi to be displayed above refrigeration (up to 25 degrees C) for a maximum of about 4 hours only where the rice is acidified to a pH of 4.6 or less, the pH is recorded, and the business has a system to track how long the sushi has been on display. Sushi held below 5 degrees C is treated like any other potentially hazardous food. Where refrigeration is not used, the 2-hour/4-hour rule is a framework many councils accept: food out of temperature control for less than 2 hours in total can be refrigerated and used; between 2 and 4 hours it should be used immediately and not returned to the fridge; at 4 hours or more it must be discarded. This time is cumulative across the day. Rules differ between states and territories, so confirm the display expectations for your setting with your local council environmental health officer. Refrigerated display below 5 degrees C is the safest default for raw-fish sushi. NSW allows acidified sushi display up to 25 degrees C for a maximum of about 4 hours, with pH recorded and time monitored. 2-hour/4-hour rule: under 2 hours use or chill; 2-4 hours use now; 4 hours or more discard. Time out of temperature control is cumulative across the day, not reset by re-chilling. Ready-to-eat handling and cross-contamination Because nothing is cooked after assembly, RTE hygiene discipline is the backbone of safety. Handle raw fish with clean, sanitised equipment and, ideally, dedicated boards and knives that are colour-coded away from raw poultry, meat and unwashed produce. Wash and sanitise hands, boards and knives between tasks, and never let raw-meat drip or raw-poultry contact reach fish that will be served raw. Minimise bare-hand contact with finished product - use gloves, tongs or clean utensils - and keep the fish cold throughout preparation by working in small batches and returning stock to refrigeration promptly. Any food handler who is unwell, particularly with vomiting or diarrhoea, must not handle RTE food. Under the Food Standards Code, businesses are generally required to take all practicable measures to prevent contamination of RTE foods, and Standard 3.2.2A has introduced food safety management requirements (such as trained food handlers and, for certain businesses, a Food Safety Supervisor and records) for prescribed higher-risk sectors. Check which obligations apply to you with your state or territory regulator. Use dedicated, sanitised boards and knives; keep raw meat and poultry well separated. Minimise bare-hand contact with finished sushi - use gloves or utensils. Exclude unwell staff from any RTE handling. Confirm your Standard 3.2.2A obligations (training, supervisor, records) with your regulator. Documenting your controls and protecting vulnerable customers An environmental health officer will expect to see that your controls are deliberate, monitored and recorded - not left to chance. At minimum, keep records of approved suppliers and product specifications, freezing/parasite-destruction confirmation, sushi rice pH or the time-control method used, receiving and storage temperatures, display times, and cleaning and sanitising. A short written procedure describing exactly how your kitchen makes sushi safely turns individual habits into a repeatable system and demonstrates due diligence. Finally, communicate honestly with customers. FSANZ advises that vulnerable people - including pregnant women, the elderly and the ill - should not eat raw fish because of risks such as Listeria, which can grow even at refrigeration temperatures; the immunocompromised and young children are also commonly advised to avoid it. Cold-smoked and gravlax-style products carry similar Listeria concerns. Where relevant, provide clear information so at-risk customers can make an informed choice. Keep records: supplier specs, freezing confirmation, rice pH or time control, temperatures, display times, cleaning. Write a short procedure so the method is repeatable and auditable. Advise vulnerable groups against raw and cold-smoked fish. Listeria can grow at fridge temperatures - cold storage alone does not eliminate it. Worked examples: A cafe adds salmon sushi: A cafe adds salmon sushi to its menu. It buys sashimi-grade salmon from a reputable supplier, confirms on the invoice that the fish was frozen to a parasite-destruction schedule, and keeps the specification as its approved-supplier record. The rice is acidified to pH 4.6 or less, checked with a calibrated pH meter and recorded, and finished sushi is held under refrigeration. Checklist: Fish sourced from a reputable supplier and labelled/intended for raw consumption. Freezing/parasite-destruction confirmed (at least 7 days, or a commercial schedule) and recorded. Fish thawed under refrigeration, sealed, on the bottom shelf, used within about 2 days. Sushi rice acidified to pH 4.6 or less, verified with a calibrated pH meter, and recorded. Non-acidified rice held at 5 degrees C or below / 60 degrees C or above. Any room-temperature display run under a valid concession, with pH recorded and display time tracked. Dedicated, sanitised boards and knives; raw meat and poultry kept separate. Bare-hand contact with finished sushi minimised; unwell staff excluded from RTE work. 2-hour/4-hour rule applied where relevant, with cumulative time tracked. Written procedure, supplier specs and monitoring records kept for due diligence. Common mistakes: Assuming freezing makes fish safe - it destroys parasites but does not kill Listeria, Vibrio or other bacteria.. Relying on a domestic freezer that cannot reach or hold parasite-destruction temperatures.. Treating acidified rice as safe without ever testing pH, or checking it only with imprecise indicator strips.. Displaying acidified sushi above refrigeration without recording pH or tracking display time.. Resetting the danger-zone clock each time food returns to the fridge instead of counting time cumulatively.. Using the same board or knife for raw chicken or meat and then for fish served raw.. Letting unwell staff handle ready-to-eat product.. Serving raw or cold-smoked fish to vulnerable customers without any advisory.. State and territory notes: NSW: The NSW Food Authority permits acidified sushi to be displayed above refrigeration (up to 25°C) for a maximum of about 4 hours only where the rice is acidified to pH 4.6 or less, the pH is recorded and display time is tracked. Other states/territories: Room-temperature display concessions and the 2-hour/4-hour rule are applied differently between jurisdictions; confirm the display expectations for your setting with your local council environmental health officer.
How to prepare a batch of sushi safely
Buy from a reputable supplier, choosing product labelled sashimi grade and intended to be eaten raw. Confirm it has been frozen to a parasite-destruction schedule and keep the invoice or specification as your approved-supplier record.
Ensure the fish has been frozen appropriately - at least 7 days frozen per FSANZ guidance, or to a commercial schedule such as -20 degrees C for 7 days or -35 degrees C for about 15 hours. If you cannot verify this reliably, use commercially frozen sashimi-grade product.
Thaw the fish in the fridge in a sealed container on the bottom shelf to prevent drips onto other food. Keep it at or below 5 degrees C and use within about 2 days of thawing.
Cook the rice, then mix in your validated vinegar preparation. Check the final pH with a calibrated pH meter and confirm it is 4.6 or less, and record it. If acidified, hold at room temperature only for the limited period your procedure allows; if not acidified, keep at 5 degrees C or below or 60 degrees C or above.
Use clean, sanitised, dedicated boards and knives kept away from raw meat and poultry. Minimise bare-hand contact, work in small chilled batches, and return fish stock to refrigeration promptly between service.
Hold finished sushi under refrigeration where possible. If displaying above refrigeration under a concession such as the NSW rule (up to 25 degrees C, maximum about 4 hours, pH recorded, time tracked), monitor and record display time. Otherwise apply the 2-hour/4-hour rule and track cumulative time, discarding product held 4 hours or more in the danger zone.
Log rice pH or time-control method, receiving and storage temperatures, display times and cleaning. File supplier and freezing records. Review your procedure periodically and confirm current requirements with your local council and state or territory food authority.
Frequently asked questions
Does freezing raw fish make it safe to eat as sushi?
Freezing controls parasites but not bacteria. FSANZ advises freezing raw fish for at least 7 days to kill parasites, yet notes freezing will not kill potentially harmful bacteria such as Listeria or Vibrio. Safe raw fish also depends on quality sourcing, an unbroken cold chain, good hygiene and no cross-contamination - freezing is only one of several controls.
What pH should sushi rice be acidified to?
Generally a final pH of 4.6 or less. At or below pH 4.6, most pathogens of concern cannot grow or produce toxin, so acidified rice can usually be treated as non-hazardous and held at room temperature. Use a validated recipe, verify with a calibrated pH meter, record the result, and follow your regulator's guidance.
What is sashimi grade or sushi grade fish?
It is a commercial quality descriptor indicating a supplier intends the fish to be eaten raw and has generally handled it accordingly. It is not a defined legal grade in the Australia New Zealand Food Standards Code, so it is not a guarantee on its own. Always confirm with your supplier that the fish has been frozen for parasite control and is intended for raw consumption.
Can I make sushi with raw fish at home safely?
You can reduce risk by buying commercially frozen, sashimi-grade fish from a reputable supplier, keeping it cold, thawing it in the fridge and preparing it with scrupulous hygiene. Domestic freezers often cannot reach parasite-destruction temperatures, so rely on commercially frozen product. Vulnerable people - pregnant women, the elderly, young children and the immunocompromised - are generally advised to avoid raw fish altogether.
How long can assembled sushi sit out of the fridge?
Assembled sushi containing raw fish or non-acidified rice is a potentially hazardous food. Refrigerated display is safest. Under a concession such as the NSW rule, acidified sushi may be displayed up to 25 degrees C for a maximum of about 4 hours with pH recorded and time tracked. Otherwise many councils accept the 2-hour/4-hour rule, counting time cumulatively across the day.
Who should not eat raw fish dishes?
FSANZ advises that vulnerable people - including pregnant women, the elderly and the ill - should not eat raw fish, largely because of Listeria, which can grow even at fridge temperatures. The immunocompromised and young children are also commonly advised to avoid it. The same caution applies to cold-smoked salmon and gravlax-style products. Offer clear information so at-risk customers can make an informed choice.
Are pH test strips good enough for checking sushi rice?
Generally no. Because acidifying rice to pH 4.6 or less is a critical control, you need the accuracy of a calibrated pH meter; indicator strips are usually not precise enough to confirm you are at or below 4.6. Check every batch, reject rice reading above 4.6, and record each result as evidence your control works.
How should I thaw frozen fish before using it for sushi?
Thaw it in the fridge, in a sealed container on the bottom shelf, so juices cannot drip onto other food. Keep it at or below 5°C throughout and use it within about two days of thawing. Handle it as ready-to-eat with clean, sanitised, dedicated boards and knives kept away from raw meat and poultry.