The Vegetarian Resource Group Blog

The Vegetarian Resource Group Blog

By Jeanne Yacoubou, MS

The Vegetarian Resource Group received an email from a reader in April 2020 asking: “Is yellow prussiate of
soda vegan?”

Here is our answer:

Yellow prussiate of soda (YPS) is
a hydrated cyanide salt approved by the Food and Drug Administration (FDA) for
use in table salt as an anti-caking agent, giving it Generally Regarded as Safe
(GRAS) status. It may appear on an ingredient label as sodium ferrocyanide
Other ways
the name appears
on a label are possible.

NOTE: Inhalation or ingestion of cyanide salts can be
fatal. The Agency
for Toxic Substances and Disease Registry (ATSDR)
“Ingestion of hydrogen cyanide solutions or cyanide salts can be rapidly
fatal…Treatment of ingested cyanide salts is similar to treatment of oral
hydrogen cyanide poisoning because cyanide salts form hydrogen cyanide in
acidic conditions.” (Stomach pH is acidic.)

The estimate of the daily acceptable limit of YPS in humans at which no
toxicological effects are observed (extrapolated from rat studies) is 0.025
mg/kg of body weight.

Although The VRG hasn’t
seen YPS on most table salt brands or varieties recently, we found a
of the ingredients
label of Morton’s® Kosher Salt that does contain YPS.

The VRG contacted three
companies that manufacture or distribute YPS or products that contain it to
find out its vegan status.

This is what we learned:

  1. Morton®

We sent an email to
Morton Salt asking about its Star-Flake®
Dendritic Salt
that contains YPS. We asked if it was completely
mineral-based with no processing by animal- or dairy-derived ingredients. The
consumer representative did not have information on this, and said it was an
industrial product. Upon closer inspection of their website, we found an email
address for inquiries into the company’s industrial products. We asked,
“… I’d like to know if the yellow prussiate of soda in your dendritic
salt is completely mineral-based? In other words, it contains no animal or
dairy ingredients and wasn’t manufactured with animal or dairy-derived processing
aids?” The next morning, we received an email response from the industrial
products division at Morton Salt. Technical Documentation Specialist Claudia
told us:

“YPS is synthetic but is
ultimately derived from minerals. I’ve included a copy of our vegetarian/vegan

Here is the statement
from Morton Salt:

“The following products
manufactured by Morton Salt, Inc. are suitable for consumption by individuals
following a vegan, lacto-ovo-vegetarian, or lacto-vegetarian diet. There is no
exposure or contact to foods of animal origin in processing equipment, storage
or handling procedures.

Food Processing

Coarse Sea Salt

Culinox® 999® Fine Salt

Culinox® 999® Food Grade


Dried Coarse Salt

Extra Coarse Sea Salt

Extra Fine 200 Salt

Extra Fine 325 Salt

Flour Sea Salt

Flour Salt

H.G. Blending Salt

H.G. Blending Prepared

Iodized Salt

Iodized Flour Salt

Iodized Snack Flour Salt


Iodized Star Flake®

ES Salt

Iodized Table Salt

Iodized PureSunTM



Lite Salt® Mixture

Medium Sea Salt

Potassium Chloride, USP

PureSunTM Culinary

Purex® Salt

Purex® All Purpose Salt

Purex® Fine Prepared

Reagent Grade Sodium


Rock Koshering Salt

Rock Pretzel Salt

Sea Salt

Select Sea Salt

Snack Flour Salt

Star Flake® Dendritic ES

Star Flake® Dendritic

TCP Extra Fine 70 Sea

TFC 999® Fine Salt

TFC 999® Salt

TFC Extra Fine 50 Sea

TFC H.G. Blending Salt

TFC Lite Salt® Mixture

TFC Medium Sea Salt

TFC PureSunTM Culinary


TFC Purex® Salt

TFC Sea Salt

TFC Select Sea Salt

Top Flake Coarse Salt

Top Flake Extra Coarse

Top Flake Fine Salt

Top Flake Topping Salt

USP Salt (Sodium

White Pretzel Coarse

White Pretzel Medium

Consumer/Food Service

All-Purpose Iodized Sea

All-Purpose Natural Sea

Canning/Pickling Salt

Coarse Kosher Salt

Evaporated Granulated

Extra Fine Sea Salt

Iodized Table Salt

Iodized Salt

Lite Salt® Mixture

Popcorn Salt

Salt Balance

Salt Substitute

Sea Salt –Coarse Salt

Sea Salt – Fine Salt

Sea Salt Grinder

Sea Salt Grinder Refill

Table Salt, Non-Iodized

Vacuum Granulated Salt”

  1. Davis Wholesale

An online search for YPS
led The VRG to Davis Wholesale Supply, distributors of Alberger® Shur-Flo®
Fine Flakes and Flour Salts
with YPS listed as an ingredient.

Company employee Kim
sent us a Safety Data Sheet (SDS) on YPS that did not have ingredient source
information. The SDS stated recommended use:

“Salt may be intended
for food or animal feed (agricultural) as well as several industrial
applications including deicing and water conditioning.”

Upon our request, Davis
employee Kim contacted Cargill, the manufacturer of the salt, about its vegan
status. She specifically asked if animal or dairy ingredients were used in the
manufacture of Alberger Shur-Flo Fine Flake Salt. In response, Cargill sent Kim
this statement titled “Vegetarian/Vegan Statement: Cargill Salt.”

In its entirety:

“The US FDA has not
defined vegetarian or vegan. The Cargill ingredients covered by this letter
have not been produced from animal (including fish), dairy, or egg products and
these products have not been added by Cargill to the Cargill ingredients.”

  1. American Elements®

The VRG also inquired
about YPS manufactured by American Elements. Product Engineer Kristi told us: “As far as I
know, none of our materials are animal- or dairy-based/derived.” Currently,
they are offering only research-grade materials, not food-grade YPS.

VRG Conclusion about YPS

According to three
companies that manufacture YPS or make products containing it, yellow prussiate
of soda is vegan. It is derived from minerals with no animal- or dairy-derived
processing aids.

For more information on
other food ingredients, please see VRG’s Guide to
Food Ingredients

The contents of this posting, our
website, and our other publications, including Vegetarian Journal, are not
intended to provide personal medical advice. Medical advice should be obtained
from a qualified health professional. We often depend on product and ingredient
information from company statements. It is impossible to be 100% sure about a
statement, info can change, people have different views, and mistakes can be
made. Please use your best judgment about whether a product is suitable for
you. To be sure, do further research or confirmation on your own.

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