Abstract

 

• Sous vide is a cooking method where food is vacuum-sealed in a special plastic bag and cooked at a precisely regulated temperature lower than usual cooking for a long period of time, in order to accurately control the doneness, quality and taste of the food and produce a quality that is difficult to achieve by conventional cooking;
• Improper temperature and time control during the sous vide cooking process may give rise to microorganism-related consumption risks;
• The Municipal Affairs Bureau (IAM) has published the “Hygiene Guidelines on Preparation of Sous Vide Food” to remind the food trade of the precautions to be taken in the preparation and processing of sous vide food, so as to reduce the risks of foodborne diseases caused by such food;
• The trade has the responsibility to make sure that the food supplied is safe, hygienic and suitable for human consumption;
• High-risk individuals such as pregnant women, infants, the elderly and people with a weak immune system should avoid sous vide foods that do not meet the pasteurisation requirements or are not fully cooked. 

 

Introduction

 

Sous vide, which has become more and more popular in recent years, is not a new cooking technique but a traditional French cooking method. Its French name, “sous vide”, can be literally translated as “under vacuum”, and in the context of cooking, it refers to the process where food is vacuum-sealed in a special plastic bag and cooked at a precisely regulated temperature lower than usual cooking for a long period of time. Sous vide is mainly used for cooking meat as its strict control of cooking temperature and time ensures the doneness, quality and taste of the meat and produces a quality that is difficult to achieve by conventional cooking. With the popularity of sous vide cooking equipment, sous vide cooking has gradually been adopted by more families.

 

Sous Vide Cooking and Consumption Risks

 

It is necessary to understand the potential consumption risks of sous vide cooking before adopting this cooking method. Although the vacuum environment is not conducive to the growth of spoilage bacteria, food may still be contaminated with anaerobic bacteria and facultative anaerobic bacteria (e.g. Clostridium botulinum, Clostridium perfringens) that can grow and multiply in an anaerobic environment. Improper temperature and time control during the sous vide process, including cooking, cooling and storage, or prolonged exposure of sous vide food in the temperature danger zone (5°C to 60°C) may result in the growth and multiplication of these bacteria. Some anaerobic bacteria will even produce lethal toxins, increasing the risk of foodborne diseases.

 

Pasteurisation is a mild heat-based sterilisation method to kill microorganisms, usually practised at temperatures below 100°C. A variety of temperature and time combinations can be used to achieve pasteurisation. Pasteurisation deactivates enzymes and destroys heat-sensitive and pathogenic microorganisms in food, thereby reducing the harmful microorganisms while retaining the nutritional value and flavour of the food. Therefore, precise control of cooking temperature and time during the sous vide process to achieve pasteurisation is the most recommended practice. To ensure food safety, the food should be cooked in a water bath until it has reached a core temperature of 64°C for 12 minutes and 37 seconds or an equivalent temperature/time combination[1] (see Table 3 of “Hygiene Guidelines on Preparation of Sous Vide Food”). Sous vide-cooked food should be consumed as soon as possible.

 

State of Regulation in Macao

 

According to Lei n.º 5/2013 “Lei de segurança alimentar” (Food Safety Law), food providers in Macao are obliged to take appropriate measures to ensure that the food supplied is safe, hygienic and suitable for human consumption. To assist the trade in preparing and providing safe sous vide food, the Municipal Affairs Bureau (IAM) has published the “Hygiene Guidelines on Preparation of Sous Vide Food” (GL 001 DSA 2023) to remind the trade of the precautions to be taken in the preparation and processing of sous vide food, so as to reduce the risks of foodborne diseases caused by such food. Additionally, IAM has also published the “Microbiological Guidelines for Ready-to-eat Food” in order to assist the trade and law enforcement officers in monitoring the risks of the microorganisms contained in ready-to-eat food (including sous vide food) and taking adequate regulatory measures. For more details on the Guidelines, please refer to the “Trade Guidelines” page on the Food Safety Information website.

Moreover, to ensure the safety of food sold in Macao, the Department of Food Safety of IAM has made continuous efforts to inspect and monitor the food production and operation premises in Macao via regular food monitoring system and inspection mechanism.

 

Advice to the Trade and the Public

 

• The trade has the responsibility to make sure that the food supplied is safe, hygienic and suitable for human consumption;
• Purchase quality meat and seafood in good hygienic conditions from reputable suppliers;
• Use equipment and appliances designed especially for or suitable for sous vide cooking according to the actual situation;
• Follow sous vide recipes that meet the pasteurisation requirements to ensure food safety;
• The water temperature in the water bath attached with the immersion circulator (namely the water bath temperature) must be stable. The temperature, together with the start and finish time of the water bath, should be measured and recorded as appropriate to make sure that the food is cooked at the accurate temperature for a proper amount of time during the sous vide process;
• The trade should proactively inform customers of food-related risks so that the latter can make the most appropriate choices in relation to their own circumstances with such knowledge;
• High-risk individuals such as pregnant women, infants, the elderly and people with a weak immune system should avoid sous vide foods that do not meet the pasteurisation requirements or are not fully cooked. 

 

References:

1.       IAM: “Hygiene Guidelines on Preparation of Sous Vide Food” (GL 001 DSA 2023), March 2023

https://www.foodsafety.gov.mo/file?p=foodsafetyinfo/returnGuideLine/638273701308232.pdf

 

2.       Food Safety Authority of Ireland: “Sous Vide and Food Safety”, July 2014

https://www.fsai.ie/publications/sous-vide-and-food-safety

       

3.       BC Centre for Disease Control: “Guidelines for restaurant sous vide cooking safety in British Columbia”, July 2017

http://www.bccdc.ca/resource-gallery/Documents/Guidelines%20and%20Forms/Guidelines%20and%20Manuals/EH/FPS/Food/SVGuidelines_FinalforWeb.pdf

       

4.       New South Wales Food Authority, Australia: “Sous vide Food safety precautions for restaurants”, May 2022

https://www.foodauthority.nsw.gov.au/media/2891

       

5.       Centre for Food Safety of the HKSAR Government: “Slow Cooking and Food Safety”, May 2014

https://www.cfs.gov.hk/english/multimedia/multimedia_pub/multimedia_pub_fsf_94_02.html

 

BRR 005 DAR 2023