Introduction to Catering Stainless Steel

Stainless steel is positioned firmly at the core of every commercial kitchen whether that's the cooking equipment, extraction, fabrications or cookware and utensils. Various types of stainless steel are used in catering settings, each having unique properties making them suitable for essential functions - from cookware and countertops to refrigeration and storage solutions. Discover why stainless steel is indispensable in creating a functional and safe culinary environment.

Catering stainless steel refers to a specific category of stainless steel designed to meet stringent quality and safety standards required for use in commercial kitchens, including hospitals, school canteens, and restaurants. Using suitable types of stainless steel for the intended purpose is crucial for maintaining the integrity of the catering equipment or stainless steel fabrication, observing cleaning and health standards and adhering to government regulations regarding food preparation and storage.

Stainless steel is the material of choice for commercial kitchens due to its exceptional properties that enhance safety, sanitation, and durability. Its anti-corrosive properties, especially in food-grade stainless steel such as 304, 316 and 430, make it resistant to various forms of corrosion, including pitting corrosion, stress corrosion cracking, and crevice corrosion, to different degrees for each grade. These are critical considerations in high-use environments such as restaurants and catering services.

• Strength and Durability
• Resistance to Corrosion and High Temperatures
• Hygienic & Easy to Clean

There are several types of stainless steel used in commercial kitchens, each providing unique benefits and applications based on their composition and properties.

Contains 18% chromium and 8% nickel (hence it sometimes being referred to 18/8). 304 stainless steel is classified as a food-grade stainless steel, renowned for its good corrosion resistance and suitability for food contact applications. It is commonly utilised in various aspects of commercial kitchens, ranging from worktops to cooking equipment. With its non-reactive surface, it ensures that food integrity is maintained, preventing unwanted flavours or chemical reactions.

Grade 304 stainless steel is not only durable but also easy to clean, making it a favourite among chefs and food service providers. It is more expensive than Grade 430 but is a practical choice in high-traffic kitchens where both aesthetics and functionality are paramount.

Contains 16-18% chromium which offers a balance between performance and cost. 430 stainless steel is a ferritic type that is cost-effective and provides some corrosion resistance. In commercial uses 430 stainless steel presents a balance between affordability and performance, allowing chefs and business owners to equip their spaces without overspending. Its applications are numerous; commonly, it is used for fabricating kitchen utensils, worktops, and food storage solutions. This versatility stems from its resistance to oxidation and ease of cleaning, which are vital in maintaining hygiene standards. 

While grade 430 offers advantages, there are limitations to consider. For instance, it may not perform as well as other stainless steels in environments exposed to harsh chemicals or extreme temperatures.

Contains 16-18% chromium and 10-14% nickel which offers superior resistance to corrosion caused by chlorides and acids. The ingredient that enhances corrosion resistance makes 316 stainless steel more a more expensive grade. This makes it perfect for equipment that experiences high exposure to salt, moisture or harsh chemicals such as commercial dishwashers and glass washers.

Gauges relate to the thickness of the stainless steel. Premium equipment that is manufactured for heavy duty use will usually have a thickness of 1.5mm (16 gauge). Stainless steel fabrications will typically have a thickness of 1.2mm (18 gauge). Equipment with a thickness of 0.9mm (20 gauge) are available however these will not offer the durability or lifespan that many chefs would expect. Read more about what you should look for when buying stainless steel catering fabricatons.

Austenitic stainless steel, particularly grade 304 and 316, is widely recognised for its excellent corrosion resistance, high ductility and formability, making it a preferred choice for various kitchen applications. Allowing for seamless fabrication, there are no crevices that food debris can get trapped in leading to improved hygiene and easier cleaning.

This exceptional material is not only popular due to its resistance to rust and staining but also its durability and ability to withstand high temperatures. Austenitic stainless steel is commonly utilised in:

• Food storage containers and gastornorm pans
• Work surfaces and catering tables
• Cooking equipment (it is non-magnetic so not suitable for induction)
• Utensils and cutlery

Martensitic stainless steel, typically grade 430, is known for its durability, hardness, it's ease of sharpening and ability to maintain a sharp edge, making it ideal for cutlery and kitchen tools.

In commercial kitchens, it is frequently used for:

• Chefs knives
• Cooking utensils
• Food processing equipment

Ferritic stainless steel, particularly grade 430, is known for its formability and cost-effectiveness, and offers moderate corrosion resistance. It is often found in environments where exposure to moisture is limited or in household settings. It has magnetic properties, is nickel free and contains 11-30% chromium.

Duplex stainless steel combines the properties of austenitic and ferritic stainless steels, providing superior corrosion resistance and strength, making it increasingly popular in commercial kitchens.

The unique composition can withstand harsh chemical environments, which are often encountered in high-stress kitchen settings. Chefs appreciate how duplex stainless steel endures continuous exposure to acidic foods and cleaning agents, reducing the likelihood of damage over time. Its impressive tensile strength makes it an ideal choice for kitchen equipment that experiences heavy loads, such as:

• Cooking station worktops
• Food preparation stainless steel tables
• Commercial dishwashers

The material's resistance to both pitting and crevice corrosion ensures that it maintains its aesthetic appeal and structural integrity even in humid environments, proving its worth in the long term.

• Catering Equipment - cooking appliances, warewashers, hot cupboards, chefs passes etc.
• Fabrications - work tables for food preparation, racking, shelves, catering sinks, commercial dish sinks and dishwasher tabling etc.
• Commercial Kitchen Extraction - canopies, filtration, ventilation etc.
• Cookware - pots and pans, cooking utensils etc.
• Refrigeration - commercial fridges, freezers, prep counters etc.

• Recognised by localised pits or dents in smooth surfaces.
• Typically caused by acids or cleaning solutions containing chloride chemically reacting with the chromium in the stainless steel over time.
• High temperatures can also contribute to pitting.

• Chloride and extremely high temperatures can lead to weakening of the stainless steel and cause cracking and weakening when subject to common stresses.
• Grade 430 is more resistant to this type of corrosion.

• Similar to pitting corrosion, this occurs when chloride solutions or acids enter crevices or joints and gradually erode protective coatings.
• Regular cleaning, which may even require disassembly, is recommended. 

Understanding the properties, benefits and pitfalls of different types of stainless steel is key to ensuring that the catering equipment and fabrications you choose are suitable for the task in hand. The manufacturers, however, are the specialists and have done the legwork for you by determining the best material for the equipment in question. The main thing you need to concentrate on is choosing the right size and capacity and most importantly, delivering professional results.