We use 2 different cooking methods in the kitchen… the traditional prepared meal process and another less familiar method called sous-vide.
The following information explains what exactly sous-vide is and what its benefits are.
Sous-vide literally means under-vacuum.
It was developed in the mid 70s by Georges Pralus for the restaurant Troisgros in Roanne, France. Originally developed for Foie Gras, the process reduced cooking loss from 30% to 5% and led to a better texture and appearance.
The simplest explanation of the process is that food is cooked in airtight pouches placed in hot water around 60°C.
The other pioneer of sous-vide is Bruno Goussault, Chief Scientist at Cuisine Solutions (USA) who has developed the parameters of cooking times and temperatures for different foods (also called cryovacking in the USA).
How does sous-vide differ from standard prepared meal production?
- Cooking time/temp is controlled so the ingredients are cooked to perfection.
- All ingredients for each portion are in the sous-vide pouch.
- Start to finish, the dish is in the pouch ensuring all flavours remain intact.
The benefits of outsourced sous-vide to the customer
- Minimal wastage/improved cost control by controlled portions
• Several meals can be reheated in the same bath (starters, mains and desserts) without cross-contamination
• Minimal training/skill required
• Garnishing of plates etc. can take place while a dish is reheating
• Extra long refrigerated defrosted shelf life means no wastage vs. fresh proteins – no additives or preservatives required
• Less freezer space required
• Reduced no of deliveries to the pub/restaurant/store
• Can be held hot longer with no evaporation or spoiling
• Less power/fuel used to produce meals. Cheaper cuts of meat can be used as sous-vide technology improves tenderness
• Minimal loss during cooking and • Consistent results every time
The benefits of sous-vide to the consumer
- Flavours and aromas are enhanced/preserved
- Colours are retained
- Little or no salt is required
- Nutrients are preserved (highest retention of vitamins vs. steaming and boiling)
- Little additional fat is required
- Enhanced textures and meat tenderness
Vacuum packing is a method whereby food (or other product) is packed and then sealed in an airless environment, usually in air-tight pouches, to prevent the chemical process known as oxidation and in the case of food, growth of harmful micro-organisms.
Unlike normal atmospheric conditions (1000 mbar), a vacuum environment has little or no oxygen, and can be held at as low as 0.5 mbar (in other words a 99% vacuum) by many but not all vacuum packing machines using vacuum pouches.
Indeed food held in an airless environment is protected from spoiling by limiting the growth of what are called aerobic bacteria i.e. bacteria that grows in oxygen, as well as mould, fungi and yeast. In addition an air-tight pouch also prevents both the evaporation of ingredients and the cross-contamination of flavours, aromas, moisture and bacteria from one piece of food to another.
How long food will remain durable after vacuum packing depends on more than just the degree of reduced oxygen. Factors such as temperature, pH, nutritive content, degree of oxygen reduction, time (age and condition) and moisture content also control the speed and level of food deterioration. However, it is a well established fact that vacuum packed food kept in the fridge at 3° C can keep food fresh for up three to five times longer than afforded by refrigeration alone. In addition, cold frozen vacuum packed food does not suffer the effects of freezer burn.
It is little wonder then that the vacuum packer has become an essential piece of kitchen equipment for many chefs and caterers. The reasons for this are not only for extended shelf life and better food preservation but also other elevated food quality and operational benefits, as follows:
Spread the workload
Sous vide (or water bath cooking)
A very high standard of hygiene
How does it work?
- “When you cook at home you get a lot of flavour in your kitchen, when you cook sous-vide, all that flavour is inside the bag” (Goussault).
- Food is cooked at relatively low temperatures (well below boiling point - e.g. 70°C) for extended periods of time that maintain the integrity of the ingredients.
- The sous-vide pouch works as a hermetic seal, keeping in both juices and aroma; and by cooking in water, you get better heat transfer than you would in an oven.