Boilers are an essential piece of equipment in many food / drink processing facilities. The FDA and NSF have released guidelines for the proper food safe chemical procedures. Chardon Labs has implemented these, and this page will focus on their approved guidance. It is essential that the chemicals fed into boiler water will not contaminate food or drinks. There are three categories to consider:
The NSF, National Science Foundation, has released specific guidelines on the use of chemicals utilized in boiler maintenance and operations. These are found in NSF’s “Registration Guidelines for Proprietary Substances and Nonfood Compounds.” Certain chemicals designated by the NSF are food safe. Here is a list of the specific chemicals from registered brands that were deemed to be food safe. You will need to look for the ones that mention being safe to be used in food processing environments.
NSF’s NFC Code G6 describes boiler chemicals that contact food or are utilized in areas with food production. The boiler’s steam may be utilized for sanitation, food processing, or to heat workspaces. One of the concerns is that the steam treated with chemicals meant to treat a boiler will contaminate the food. The code breaks down two important categories: chemicals that will contact food, and chemicals that will not contact food whatsoever. Ingredients need to be clearly conveyed for this application. These substances first need to be acceptable under FDA guidelines from Title 21. Additionally, they need to be acceptable under CFR part 182 “Substances Generally Recognized as Safe” and part 184 “Direct Food Substances Affirmed as Generally Recognized as Safe.”
NSF’s NFC Code G7 is specifically for boiler treatment chemicals that will not contact food, where they are used in areas of food production. There are specific chemicals deemed to be unsafe and are referred to as nonfood compounds. These include heavy metals, carcinogens, and other harmful substances. Chemicals used in these environments should be acceptable and not contain these, even if they will not come into contact with food. Of course, all G6 chemicals would be acceptable to utilize in applications that do not contact food as well.
The specific NSF guidance that is relevant to boiler food safety is NSF / ANSI 5. This guidance establishes cleanliness and health requirements related to boilers in food applications. It outlines operational, mechanical, and planning of boiler systems, amongst other information.
The NSF’s guidance is a continuation of the FDA Title 21 Code.
The FDA, Food and Drug Administration, has released CFR Title 21 Code, specifically Sec. 173.310 “Boiler Water Additives.”
The chemicals and additives below are what should be utilized for boiler water treatment in food grade applications. Other chemicals and additives not listed here will need to seek additional approval from the FDA.
It is important that these chemicals and additives are only utilized in the amount that they are needed. Amounts needed in preventing corrosion, scale, etc. are acceptable, but additional amounts are not. This is to keep the level of potential contamination at a safe level.
Another regulation is that the chemicals are properly labeled. This includes instructions on proper handling of the chemicals and additives. Also, it is required that its specific ingredients are named correctly and simply.
The following FDA food safe boiler chemicals and additives, as well as their specific rules, are listed below:
|
Chemicals & Additives |
Rules |
|
Acrylamide sodium acrylate resin |
The weight of the acrylamide monomer should not exceed .05%. |
|
Acrylic acid 2-acrylamido-2-methyl propane sulfonic acid copolymer |
Total not to exceed 20 parts per million (active) in boiler feedwater. The active parts of this in boiler feedwater should not exceed 20ppm. |
|
Ammonium alginate |
N/A |
|
Cobalt sulfate (as catalyst) |
N/A |
|
1-hydroxyethylidene-1,1-diphosphonic acid, plus related sodium and potassium salts |
N/A |
|
Lignosulfonic acid |
N/A |
|
Monobutyl ethers of polyethylene-polypropylene glycol |
The molecular mass should be at least 1,500 grams. |
|
The poly version of acrylic acid-co-hypophosphite, or sodium salt |
Total not to exceed 1.5 parts per million in boiler feed water. The copolymer should not be more than .05%. The amount of boiler feed water to be less than or equal to 1.5 ppm. |
|
Polyethylene glycol |
This version of glycol is the one commonly used in food-grade applications; it does have specific regulations around its specific concentrations.
The molecular weight of this should be between 200g and 9,500g. It should have less than or equal to .2% diethylene or ethylene glycol. (An analytical method shall be used. This method is based off of The United States Pharmacopeia XX- The National Formulary XV found here. |
|
Polymaleic acid plus related sodium salt |
Total not to exceed 1 part per million in boiler feed water (calculated as the acid). |
|
Polyoxypropylene glycol |
The molecular weight of this needs to be at least 1,000g. |
|
Potassium carbonate |
N/A |
|
Potassium tripolyphosphate |
N/A |
|
Sodium acetate, sodium hexametaphosphate, sodium humate, sodium hydroxide, sodium lignosulfonate, sodium metabisulfite, sodium metasilicate, sodium alginate, sodium aluminate, sodium carbonate, sodium nitrate, sodium phosphate, sodium polyacrylate, sodium polymethacrylate, sodium silicate, sodium sulfate, sodium sulfite, sodium tripolyphosphate |
N/A |
|
Sodium carboxymethylcellulose |
At least 95% sodium carboxymethylcellulose. The maximum substitution allowed is .9 . Contains not less than 95 percent sodium carboxymethylcellulose. Viscosity needs to be at least 15 cP per anhydro glucose. This is for the weight of 2% and is at 25 °C. Viscosity of Cellulose Gum (page 1128) describes this method. |
|
Sodium glucoheptonate |
No more than 1ppm of cyanide. |
|
Sorbitol anhydride esters |
Components in the steam must be less than or equal to 15 mg per kg. |
|
Tannin / quebracho extract |
N/A |
|
Tetrasodium EDTA, & tetrasodium pyrophosphate |
N/A |
The chemicals & additives below can be utilized alone, or in combination with the above chemicals and additives. The rules are for it present in steam.
|
Chemicals & Additives |
Rules |
|
Cyclohexylamine |
Apart from milk products, they cannot have more than 10ppm of this present. |
|
Diethylaminoethanol |
Apart from milk products, it cannot have more than 15ppm of this present. |
|
Hydrazine |
0ppm present. |
|
Morpholine |
Apart from milk products, they cannot have more than 10ppm of this present. |
|
Octadecylamine |
Apart from milk products, it cannot have more than 3ppm of this present. |
|
Trisodium nitrilotriacetate |
Do not use it with milk products. Less than or equal to 5ppm in feedwater. |
Please note, the regulations stated above were simplified and for more specific information, refer to the original FDA code.
Whether it is steam boilers or hot water supply boilers, process water will cause issues in them if left untreated. A factor that’s especially important in food / drink processing applications is purity. You want anything edible to not interact with harmful chemicals. Here are the types of chemicals you must utilize in a boiler, which you need to be sure are food grade safe to touch or be in the same facility as your food / drink processing.
Descaling- Descalers or scale inhibitors are utilized to disperse scale in water. They have a similar effect as water softeners and filters, removing mineral particulates that build up as water deposits. Often these scale deposits form rings around pipes and insulate the metal material. Since the purpose of this material is to conduct heat, this is counterproductive. In addition to decreased efficiency, there can be a significant decrease in water flow caused by scale. This can be compared to a wall that has been painted many times, what was once a thin layer of paint has become multiple thick layers of various colors that built up overtime. These scale layers squeeze the surface of the pipe, allowing less water to flow through it.
Corrosion Inhibitors- Corrosion / rust inhibitors or oxygen scavengers take out the oxygen from boiler water. Oxygen is the element in water that causes corrosion on metal boiler surfaces. In addition to removing oxygen, Tannin will leave a protective layer around the metal surface, shielding it from rust. Corrosion can make heat transfer surfaces less efficient and can lead to serious mechanical issues. Leaks and other issues are prone to occur as corrosion deteriorates boiler systems.
pH Builders- It is important to balance the alkalinity and acid in boilers to reach a desired pH. The operating temperature, chemicals used, and boiler material are all important factors to factor into what pH to keep your boiler system at. Acidic corrosion is a concern in the boiler if the pH is kept too low.
Amines- Amines are useful to fight corrosion. They are commonly used in condensate lines. Condensate lines tend to become acidic and the carbonic acid that usually forms here becomes neutralized by amines. Carbonic acid is highly corrosive and would cause significant corrosion otherwise. Under the guidance of AAMI ST79 for food grade applications, amines should not be pumped into steam lines or headers. Amines need to be pumped into the feedwater in the food/beverage industry.
Breweries & Distilleries- Steam boilers are commonly used heating equipment utilized in breweries and distilleries. With processing, one most important aspect of the boiler in this facility is its temperature regulation. Incorrect temperatures can result in mashing yeast being difficult to convert over, recirculating sugar having difficulty fermenting, and sparging overheating resulting in astringency. Scale and corrosion can cause uneven heat distribution. Additionally, imbalanced pH can cause a significant change in flavor. In order to balance these issues, while keeping your beer and spirits pure you need food safe boiler chemicals.
Food Packaging- Chardon Labs has the pleasure of working with some of the largest food packagers in the US. Sanitation and safety are a top concern when dealing with plastic or other materials that come into direct contact with foods and beverages. Boilers may be utilized for the sanitation itself or as process equipment in the case of injection molding.
Beverages- Boilers are commonly utilized in the heating operation of certain drinks. In addition to this, boilers are an effective way to sterilize the equipment used for it. Impurities in beverages can cause a significant problem. The beverage’s water likely already has to be filtered and processed (usually with a reverse osmosis or other strategy). You do not want contamination to occur because of your boiler’s chemicals.
Meat- It’s no secret that poultry, beef, fish, and other forms of meat are common carriers of disease. As such, boilers are a useful way to clean equipment and to heat the meat effectively. Boilers typically handle a large volume of meat at a time, surrounding the vats with high-temperature steam to cook it thoroughly. In this application the boiler’s steam would come into direct contact with the meat products and it would need to be considered non-hazardous.
Do you need chemicals safe to utilize in your food or drink facility? If safety and health is a concern to you, contact Chardon Labs for Food Grade Boiler Chemical Treatment Services. We will help you make sure impurities do not get into your edible products or their packaging. We handle several clients in the food and beverage space, keeping customers safe for years. To get a free in-person technical survey of your facility or for other food grade boiler chemical water treatment questions, fill out this contact form. (It takes under a minute). Or give us a ring at (380) 224-7395 and we will connect you with a local service manager who can help!
