Hygienic valves (also called sanitary stainless steel valves or food-grade valves) are valves designed for the food & beverage (F&B) and pharmaceutical industries, where pipelines come into direct contact with consumable products. Hygienic valves are characterized by an AISI 316L stainless steel body, a smooth crevice-free surface, self-draining construction, food-grade seals, and the ability to clean in place (CIP/SIP) — meeting international sanitary standards such as EHEDG, 3-A and FDA. This article classifies 5 groups of hygienic valves and explains the standards so you can select the right valve for your process line.
- Hygienic valve = sanitary valve for F&B/pharmaceutical: AISI 316L stainless steel, crevice-free, self-draining, food-grade seals, CIP/SIP.
- Recognition standards: EHEDG, 3-A, FDA — ensuring safe, cleanable product-contact surfaces.
- 5 main groups: shut-off (butterfly/ball/diaphragm), mixproof (anti-mixing), control, automation, aseptic sampling.
- Butterfly valve: compact – fast shut-off; ball valve: tight seal – higher pressure rating for viscous/particulate fluids.
- Mixproof valve with a safety leak cavity in the middle: CIP one line while the other continues running product without product mixing.
What is a hygienic valve and how does it differ from a standard industrial valve?
Definition and Core Characteristics
Standard industrial valves focus on open-close operation and pressure rating. Hygienic valves add a critical requirement: the product-contact surface must be completely clean and sanitizable without disassembly. To achieve this, hygienic valves are manufactured according to four hygienic design principles:
- AISI 316L stainless steel material — corrosion-resistant, tolerates CIP chemicals (acids/alkalis), does not leach contaminants into the product.
- Crevice-free — no dead zones or open grooves where bacteria can accumulate; smooth internal surface (low Ra roughness).
- Self-draining — when installed at the correct slope, fluid drains completely without pooling, preventing bacterial growth.
- Food-grade seals — EPDM, FKM or PTFE materials suited to the fluid type, resistant to heat and cleaning chemicals.
As a result, hygienic valves allow Cleaning in Place (CIP) with recirculating cleaning solution and Sterilization in Place (SIP) with hot steam — without disassembling the valve for cleaning, reducing downtime and the risk of cross-contamination.
Hygienic valve standards: EHEDG, 3-A and FDA
Understanding Each Sanitary Certification
When selecting valves for an F&B or pharmaceutical line, the three standards below are the technical reference for confirming that a valve is genuinely hygienic:
| Standard | Origin | Significance for Users |
|---|---|---|
| EHEDG | Europe (European Hygienic Engineering & Design Group) | Certifies cleanable-by-CIP design, crevice-free — widely used for EU and global markets. |
| 3-A | USA (3-A Sanitary Standards) | Sanitary standard for dairy and food processing equipment; focuses on materials and contact surfaces. |
| FDA | USA (Food & Drug Administration) | Regulations on materials (seals, plastics) permitted to be in direct contact with food/pharmaceuticals. |
A certified hygienic valve typically states its certification by product line. When requesting a quotation, specify the fluid, temperature, operating pressure, and required standard to receive guidance on the appropriate seal configuration and materials.
Hygienic valve classification: 5 functional groups
Select by Function on the Process Line
Hygienic valves are classified by their function on the pipeline. The table below summarizes 5 groups and typical use cases:
| Group | Function | When to Use |
|---|---|---|
| Shut-off / Diverting | Open–close, redirect flow | Isolate pipelines, split flow; butterfly valve for fast shut-off, ball valve for high pressure and viscous/particulate fluids. |
| Mixproof (anti-mixing) | Prevent mixing of two streams | When CIP-ing one line while the other continues running product — the middle leak cavity ensures no mixing. |
| Control / Protection | Maintain flow rate/pressure, protect against overpressure | Stabilize flow (4-20 mA positioner), protect tanks from overpressure/vacuum, air release. |
| Automation | Position feedback, automated CIP, product recovery | Integrate actuator heads, pigging systems, tank top modules for automated plants. |
| Aseptic sampling | Cross-contamination-free QC sampling | Sampling liquids, solid powders, or via membrane for quality control. |
How do butterfly, ball, and mixproof valves differ?
Three Common Shut-off Valve Types
These are the three types most commonly asked about when starting to design a hygienic pipeline:
- Butterfly valve — compact, lightweight, reasonably priced, fast shut-off via rotating disc. Suitable for large pipelines, thin fluids, and frequent open-close operation.
- Ball valve — high sealing integrity, higher pressure rating than butterfly valve, unrestricted flow path. Suitable for viscous fluids, particulate fluids, or applications requiring reliable sealing.
- Mixproof valve (anti-mixing) — has two independent valve plugs and a safety leak cavity in the middle. If one plug leaks, fluid drains to the middle cavity and exits externally instead of mixing into the other stream. This allows CIP-ing one line while the other continues running product — a key factor for food safety in continuously running plants.
In addition, the diaphragm valve uses a membrane that completely separates the actuating mechanism from the fluid, suitable for sensitive fluids or applications requiring high sterility; a check valve prevents backflow.
DEFINOX · FRANCE Complete Hygienic Valve Solution
Definox (France) is a hygienic valve brand dedicated to F&B and pharmaceutical applications, distributed by TKT Pumps in Vietnam. The entire valve range uses AISI 316L stainless steel, crevice-free – self-draining – CIP/SIP design, EPDM/FKM/PTFE seals, and is EHEDG/3-A certified by product line. The product range covers all 5 functional groups: DPX/DPX3 butterfly valves, DBX ball valves, DCX3/DCX4/DMX/CAR diverting valves (shut-off, DN8–150, up to 20 bar with ball valve); VEOX mixproof valves (two plugs + leak cavity), NEOS, VDCI MC, VEOX FC (DN25–150, up to 13 bar, PEEK/PFA plugs); DCX3 control valve with 4-20 mA positioner, pressure reducing/safety valves 0.2–13 bar and AVX1 metering/air release; SORIO actuator heads (AS-i/IO-Link, IP67, ATEX) and STARMOTION pigging system; along with the aseptic sampling group PEX/PEAX (liquid), PEV (solid/powder), DMX-PE (membrane). Clamp/weld/threaded connections, manual or pneumatic operation with Sorio actuator.
Frequently Asked Questions about Hygienic Valves
What is a hygienic valve?
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A hygienic valve is a stainless steel valve used in the food & beverage and pharmaceutical industries, featuring an AISI 316L stainless steel body, crevice-free surface, self-draining construction, food-grade seals, and in-place cleaning capability (CIP/SIP). The valve meets sanitary standards such as EHEDG, 3-A and FDA to ensure the fluid is free from bacterial contamination and material leaching.
Why do hygienic valves use 316L stainless steel?
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AISI 316L stainless steel offers better corrosion resistance than 304 due to its molybdenum content, tolerates CIP chemicals including acids and alkalis, and does not leach contaminants into the product. The low carbon content (the “L”) reduces weld corrosion, making it suitable for food and pharmaceutical product-contact surfaces.
What is the difference between CIP and SIP?
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CIP (Cleaning in Place) is in-place cleaning with a recirculating cleaning solution through the pipeline without disassembling the equipment. SIP (Sterilization in Place) is in-place sterilization with hot steam to eliminate microorganisms. Hygienic valves are designed to withstand both processes.
When should a mixproof valve be used?
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Use a mixproof valve (anti-mixing) when CIP-ing one pipeline is required while another pipeline is still running product and mixing is absolutely not permitted. The valve has two independent plugs and a safety leak cavity in the middle: if one plug leaks, fluid drains to the middle cavity and exits externally instead of mixing into the other stream, ensuring food safety in continuously running plants.
Should I choose a butterfly valve or ball valve for a hygienic process line?
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Choose a butterfly valve when compact, lightweight construction and fast shut-off on large pipelines with thin fluids are needed. Choose a ball valve when higher sealing integrity, a higher pressure rating, or viscous and particulate fluids are involved. The specific choice also depends on the fluid, pressure, temperature, and CIP requirements of each process line.
What standards does the Definox hygienic valve meet?
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The Definox hygienic valve uses AISI 316L stainless steel, features a hygienic crevice-free – self-draining – CIP/SIP design, EPDM/FKM/PTFE seals, and is EHEDG/3-A certified by product line. The brand covers all 5 functional groups from shut-off, mixproof, control, and automation to aseptic sampling for F&B and pharmaceutical applications.
Send a consultation request or hotline 0941.400.488
Source: Definox (France) technical documentation and the EHEDG, 3-A, FDA sanitary standards. Compiled by TKT Pumps.
