Sous vide cooking brings tremendous benefit to the kitchen and bar aside from elevating the organoleptic qualities of the food or beverage being prepared, sous vide enhances food safety. Food safety is a topic of immense scope. The information below is intended to be a quick reference of best practices. For more in-depth information, contact your local food safety authority directly.
Food safety before cooking
It has always been our stance that sous vide cooking as a method of food preparation is as safe and any other cooking method. It is important however to follow certain guidelines to ensure food safety when cooking sous vide, as with any other cooking method.
– Basic hygiene practices: wash your hands, use clean cutting boards, surfaces and containers
– Wash produce and discard less-quality items or use them for other purposes
– Separate raw and cooked products to prevent cross-contamination
– Ensure that food is not held in the Temperature Danger Zone (40 – 135ºF) for more than 2 hours.
Food safety during cooking
In order to reduce pathogens in food to safe levels, cook food to its minimum internal temperature at the slowest heating part of the product and hold that temperature for a specific amount of time.
– Seafood – 145ºF for 15 seconds
– Pork, Ham, Game Animals, Eggs – 145ºF for 15 seconds
– Ground beef (or mechanically tenderized or injected) – 155ºF for 15 seconds
– Poultry, Stuffed fish, Stuffed meat, Stuffed pasta, Stuffed poultry, or Stuffing containing fish, meat and poultry – 165ºF for 15 seconds
– Roast beef – 130ºF for 112 minutes or 145ºF for 3 minutes
– Fresh, frozen, or canned fruits and vegetables – 135ºF for hot holding – If it is cooked for immediate service, there is no temperature requirement according to the 2017 code. It is based on the customer’s request.
You may be asking, “How do I measure the temperature of my food if it is in a bag?”. As a best practice, we always recommend cooking animal proteins with a hypodermic temperature probe and foam tape to monitor the temperature as it cooks.
Food should be pasteurized during the Sous Vide cooking process if
– You are cooking for the young, elderly, potentially immune-compromised (or if you are unsure of who will consume the food)
– The food has been mechanically tenderized, ground or injected
– Or you simply want to follow best practice
The added benefit of pasteurizing during the cooking process is that the food will have an extended shelf life. The caveat here is proper chilling and cold storage.
Pasteurization is a log reduction of pathogens that makes food safer to consume and extends the product’s shelf life. This occurs as a function of time and temperature, being measured from the slowest heating point of the food product. Immersion circulators keep the cooking environment at an extremely precise, constant temperature. This makes them ideal for pasteurizing the food as part of the cooking process. The amount of time which a food takes to reach a given temperature depends on its thermal conductivity. The type of food, shape, and thickness (thickest point) are the most critical determining factors of a food’s thermal conductivity.
Some spores are relatively heat-resistant and can survive the most minimal heat treatments that destroy vegetative cells. Mild heat treatments (heat shocks) in combination with sous-vide may actually select for C. botulinum by killing off competitors (preservation bacteria). If present, spores survive the sous-vide cooking temperature, they can start germination once the temperature is favorable. So the measures to control it are: buy from good/safe source, implement good handling practices, avoid temperature abuse, short cooling period, maintain cold storage and use within the shelf-life period.
“So how long does pasteurization take?”. This is an impossible question to answer for all foods, because thickness, density and even a food’s cellular structure come into play. The amount of time required to pasteurize the food to a core level is determined by the the type of protein, targeted bacteria, and the temperature at which you are holding the food product. Three main references that we frequently use to determine pasteurization times are
– The PolyScience Sous Vide Toolbox on the iOS App Store – Get it here!
– Dr. Douglas Baldwin’s work – http://www.douglasbaldwin.com.
– Appendix 3 – Equivalent processes to achieve 70ºC for 2 minutes from Campden BRI Guideline 51 – Pasteurization: A Food Industry Practical Guide (second edition, 2006)
Remember that as a best practice we always recommend cooking animal proteins with a hypodermic temperature probe and foam tape to monitor the temperature as it cooks. The PolyScience Sous Vide Toolbox and Dr. Douglas Baldwin’s work rely on mathematical calculation to very accurately predict core temperature and pasteurization curves.
This post has been a collaboration between Breville | PolyScience and the team at CREA. For more information regarding sous vide cooking and vacuum sealing technique, please visit their selection of courses HERE. CREA is the research academy, founded by Dr. Bruno Goussault whom is widely accredited as the founder of sous vide cooking. Dr. Goussault was honored by the prestigious Einstein Legacy Project as one of the world’s 100 greatest innovators of the century for his pioneering work in this field. Sous vide cooking is a specialized process that requires an approved HACCP Plan or variance for the USA. CREA is your go-to resource to help build those plans.