Walk-in is the shortened or slang term for the “walk in refrigerator” in commercial restaurant kitchens. This is not to be confused with the term walk-in as used in the front of the house.
These are simply refrigerated spaces that are so large you can walk into them. Like a large refrigerated walk-in closet, they have shelves on either side and are used for the extended storage of bulk food items such as large boxes of vegetable or fruit, or for the shorter-term storage of batch prepared foods.
Modern walk-in cooler units come in many different sizes to suit the space available and storage needs of smaller and large restaurants.
They are built from insulated wall panels.
An entire walk-in unit does not have to be transported to a restaurant to be placed inside the kitchen.
Even if this were true, it could be impossible to get it into the restaurant. Instead, the wall panels can be snapped together on-site.
Although walk ins do come in smaller and larger sizes, they a great deal of space, which most small kitchens cannot afford to give up.
However, walk-in refrigerators can also be placed outside and fitted with a weather-cap over the top. Many restaurants have their walk-ins just out back, and some even have a hole cut in the back wall so that the staff can enter the walk in from the kitchen without having to go outside.
Walk-ins are meant to be accessible with wheeled carts for carrying heavy items and boxes in and out, so a ramp must be fitted at the entrance to the fridge.
Just because walk ins are so large, doesn’t mean that everything can be stored in them together. Some larger restaurants will have more than one. For example, a steak-house which dry-ages large cuts of beef will need a very large walk in for just this purpose, to provide the space needed and to allow the beef to age at the proper temperature and humidity. As well, strong-smelling foods, such as stinky cheese, should not be stored with vegetables, as the vegetables may pick up the odors.
Walk-in refrigerator image © Sebastian Czapnik