Steaming Equipment: Steam Cabinets, Continuous Steamers, and Boiler Regulations

What Do Bun Factories Steam With?

For steamed products such as buns, mantou, shumai, and xiaolongbao, there are three common types of cooking equipment:

• Bamboo steamers and steam stoves: The most traditional method, heating water in a pot with gas or electricity to generate steam. Suitable for small shops and test batches.
• Steam cabinets: A cabinet with a door, holding carts or racks inside, either connected to an external steam supply or with built-in heating. It can steam many trays at once in batches and offers great flexibility for switching products, making it the workhorse of small and medium-sized factories.
• Continuous steamers: Products sit on a conveyor belt and pass through a steam-filled tunnel, going in one end and coming out the other cooked. Steaming time is controlled by the belt speed.

Who Are Continuous Steamers For?

The advantages of continuous steamers are consistency and labor savings: every bun passes through the same time and temperature, so there's no "the first tray and the last tray are different" problem, and no one has to carry trays in and out. They suit:

• Simple product ranges at high volume: Running the same one or two kinds of buns every day, with high output requirements.
• Lines where upstream and downstream are already automated: A forming machine upstream that arranges trays or feeds directly onto a conveyor, and cooling and quick freezing downstream, so the whole line doesn't break at the steaming stage.
• Factories with enough length: Continuous equipment takes up length, so reserve space for loading, unloading, and maintenance.

Conversely, factories with many products, small batches, and frequent product changes usually do better with the flexibility of steam cabinets. Batch steam cabinets also make it easier to start small and add units as output grows.

After steaming, buns usually need to be cooled before going into the blast freezer. Steamed buns left too long at room temperature collect water on the surface and pose a greater hygiene risk, so plan the distance and pace between the steamer and the cooling and quick-freezing equipment together.

Where Does the Steam Come From?

• Built-in steam generators: Some steam cabinets or steamers have a built-in heated water tank and work as soon as you plug them in or connect gas; installation is simple.
• Central boiler supply: Large factories use one boiler to supply steam to multiple steamers, blanchers, or cleaning operations, which is efficient but involves boiler regulations.

When steam contacts food directly, pay special attention to the choice of boiler water treatment chemicals to avoid affecting food safety; you can confirm with your water treatment supplier whether a product is suitable for food-contact steam.

What Regulations Apply to Boilers?

Boilers are divided by capacity into those classified as "hazardous equipment" and "small boilers," with different requirements:

• Occupational Safety and Health Act (職業安全衛生法) Article 16: Machinery or equipment designated as hazardous by the central competent authority may not be used unless it has passed inspection by a labor inspection agency or an authorized inspection agency; after the specified period, it must pass re-inspection to continue in use.
• Enforcement Rules of the Occupational Safety and Health Act (職業安全衛生法施行細則) Article 23: Hazardous equipment includes boilers, pressure vessels, and the like above a certain capacity.
• Safety Inspection Regulations for Hazardous Machinery and Equipment (危險性機械及設備安全檢查規則) Article 4: Lists the capacity thresholds at which a boiler counts as hazardous equipment, for example steam boilers with a maximum working pressure above 1 kg per square centimeter or a heating surface area above 1 square meter. Articles 81 and 82 of the same Regulations require a completion inspection after a boiler is installed, and it may not be used until it passes; the inspection certificate is valid for at most 1 year, and a periodic inspection must be applied for before it expires.
• Safety Regulations for Boilers and Pressure Vessels (鍋爐及壓力容器安全規則) Article 3: Defines "small boilers"; Article 24 requires small boilers to be constructed in accordance with national standard CNS 10897.
• Operator qualifications: Article 24 of the Occupational Safety and Health Act requires operators of hazardous equipment to complete recognized training or pass a skills test; Article 13 of the Regulations for Occupational Safety and Health Education and Training (職業安全衛生教育訓練規則) lists boiler operators, and Article 14 requires small boiler operators to receive special-operation safety and health training.

Which category your boiler falls into depends on the maximum working pressure and heating surface area on its nameplate, compared against the provisions above; if unsure, check with the boiler manufacturer or your local labor inspection agency.

FAQ

Q: For a bun factory just starting out, should I buy a steam cabinet or a continuous steamer?
A: With many products and growing volume, a steam cabinet offers more flexibility; a continuous steamer only makes sense with a simple product range, high volume, and automated upstream and downstream.

Q: Does a factory boiler need regular inspection?
A: A boiler classified as hazardous equipment must pass a completion inspection before use; the certificate is valid for at most 1 year, and a periodic inspection must be applied for before it expires.

Q: Do small boilers require certification?
A: Under Article 14 of the Regulations for Occupational Safety and Health Education and Training, small boiler operators must receive special-operation safety and health training.

Q: Can Dong-Yih's bun machine connect to a continuous steamer?
A: To discuss how Dong-Yih Machinery's Automatic Steamed Bun and Mantou Machine DY-201 pairs with upstream and downstream equipment, call us at 06-257-4644.