Information > Food Grade Coatings
Food Grade Coatings
We Can Help You Meet FDA Regulations
Food grade coatings must comply with FDA regulations in 21 CFR 177.1550 governing
components of coatings for direct food contact. The FDA and other regulatory
bodies dealing with the food and pharmaceutical industries require that strict
guidelines be followed in any process affecting their manufacturing equipment.
While there are many coatings (such as wax coatings on meat wrapping paper)
available that comply with FDA regulations, the FDA conforming coatings that
we apply are metallic and fluoropolymer coatings.
Common Food Grade Coatings
Electroless Nickel (EN) is an autocatalytic coating, often recommended for
use on steel parts.
A minimum thickness of .001" of Electroless Nickel will adequately protect
the metal base from corrosion. Electroless Nickel is, in actuality, not nickel,
but a nickel-phosphorous overlay.
This coating will resist caustic, sulfate, chloride and other organic solutions
but nitrates will discolor the surface. Additionally, Electroless Nickel has
good lubricity and a Rockwell hardness ranging from 52-60.
It has several unique advantages; as an electroless process, it can be applied
to inside diameters and even blind holes. It is extremely uniform in thickness
as can even be used to restore undersized threads without the need for subsequent
grinding. It can be heat treated to high hardness, and is non-conducting, which
is important where galvanic attack is a consideration.
EN/PTFE is a unique combination of EN co-deposited with a fluoropolymer (PTFE).
It can be applied at thicknesses up to .003" although it makes a better
coating in most cases at thickness of .0003"-.0005".
It uniquely combines the properties of EN with the properties of PTFE allowing
for greater lubricity, release and non-stick properties.
Fluoropolymer coatings can be applied as the final step or as the only finishing
step in any metal manufacturing process in order to increase a parts release
After a fluoropolymer application, a part will feel slick to the touch and
will exhibit a very low coefficient of friction. Some parts used in high-stress
environments such as bending or sliding require a fluoropolymer coating.
Clear fluoropolymer coatings can be used so as not to change the color of
the underlying part, since they will merely reflect the color of the base material.
Hard coat Anodizing (HCA) is an electrochemical process is applied to aluminum
alloys, which transforms the surface to aluminum oxide. It transforms the soft
aluminum into a wear and corrosion resistant medium, attaining a Rockwell hardness
of 48-54. Like EN, HCA also has good lubricity.
Choosing a proper aluminum alloy prior to manufacturing will allow for determination
of the eventual thickness, corrosion resistance, and color of the alloy, since
every alloy responds differently to the coating process.
Harsh caustic or highly acidic solutions will eventually disintegrate a hard
coat part, requiring that highly trained and highly knowledgeable personnel
understand that concentrated solutions are not always superior in a maintenance
wash down, but rather that mild detergents in warm water will extend the longevity
of the coating.
Passivation is not a coating; however, it is very useful in creating a very
smooth, clean surface on metal parts such as stainless steel, aluminum and
Passivation remove traces of iron embedded at the surface of metal parts during
manufacturing processes such as machining and milling. Passivating actually
cleans the surface of all metallic impurities, making it an essential part
of the metal manufacturing cycle for food grade equipment.
Electropolishing is also not a coating. It makes all kinds of metal parts
last longer and perform better.
Electropolishing uses a reverse plating technique where a metal or alloy is
immersed in a chemically balanced solution through which a low voltage current
is passed. In this controlled process, just the right amount of surface metal
Electropolishing does not smear, bend, stress or fracture the metal. It results
in a smooth, lustrous, more corrosion resistant finish that is passive and
less prone to metal fatigue. It is generally less expensive than mechanical
polishing and produces far superior results, leaving the surface microscopically
Contact ICS TECHNOLOGIES for help selecting the right food grade coating for