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Beit Midrash Family and Society The Laws of Kashrut

Glycerin in Today’s World - Or "How I Stopped a Catastrophe"

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Question #1:
"In what types of food products is glycerin used?"

Question #2:
"Is glycerin kosher?"

Question #3:
"What is the difference between glycerin, glycerine, and glycerol?"

Question #4:
"The other day, I was using some vanilla extract in a recipe and noticed that the extract itself had a sweet taste. I know that vanilla is usually extracted with alcohol, but this particular product was labeled "alcohol-free," and apparently used glycerin instead. I am curious about the nutritional properties of glycerin. Does it affect the body like sugar? Is it calorie-free?"
Glycerin comes from fats (either animal, vegetable or mineral) and originally was a by-product of soap or candle manufacture. The process of producing soap has not changed significantly since it was first discovered thousands of years ago. The method is very similar to that described by the halachic authorities, who refer to a process of cooking fat and ashes together. Today, we call these ashes lye, and it usually consists predominantly of sodium hydroxide or potassium hydroxide, both alkalis. Cooking these together with fat creates a chemical reaction called saponification, from the Latin word sapo, meaning soap. The process converts the fat and alkali into soap and an alcohol such as glycerin. The glycerin splits off from the fatty acids and mixes together with water, forming an odorless, sweet-tasting, syrup-like liquid.
Glycerin is also created naturally in the process of manufacturing some alcoholic beverages. It can also be produced chemically from petroleum, but, in the United States, glycerin from petroleum is not generally used in food.
Properties of glycerin
Glycerin, sometimes spelled glycerine, and sometimes called glycerol, has a number of interesting properties. Mixing glycerin with nitric acid creates nitroglycerine, which can be used to treat chest pain or to blow up mountains or enemies. Glycerin attracts water like a sponge, making it useful for skin care, since adding it to a lotion or cosmetic will help your skin remain moist. It is also commonly added to soaps, candles, deodorants and makeup. You might find glycerin in toothpaste, which will help prevent drying out or hardening in the tube.
Glycerin is a common ingredient in pharmaceuticals, including heart medication, suppositories, cough remedies and anesthetics. For example, it allows the medicinal agent in the cough syrup to coat the throat of the patient. Since glycerin is water based, it is very useful for this application. In addition, glycerin’s sweetness may mask the distaste of the anti-cough agent, thus making the syrup smoother and tastier. Mixed into wax and used as a suppository, glycerin’s moisture-attracting properties draws water from the body into the colon, which stimulates a bowel movement.
Athletics and glycerin
Athletes run a constant concern about dehydration, and drinking large quantities of water or sports drinks usually results in quickly losing a sizable portion of the fluid through urination. One still-being-researched suggestion is to add a tiny amount of glycerin to water drunk before exercise. Some contend that this increases fluid retention considerably.
Food uses of glycerin
Since glycerin absorbs moisture, it may keep a product moist for a longer period of time. Thus, it is useful as a safe preservative, and, has a marketing advantage that it does not to be listed as a preservative. Used in a product like a cereal bar, glycerin helps it avoid becoming hard and brittle. When used to coat raisins, glycerin keeps them from sticking to one another. Since glycerin has a syrupy texture, it may be used in a glaze or as a thickener. Since it coats the throat, it is sometimes used as an ingredient in whiskeys.
Glycerin is often added to foods to help oil-based and water-based ingredients mix. It can be used to prevent ice crystals from forming in frozen foods, such as frozen yogurt, ice cream and other desserts.
Is glycerin used as a sweetener?
Who would expect that a processed derivative of oils or fats would be sweet? Glycerin’s sweetness is one of the great, low-key gifts that Hashem bestows on us. Because it is sweet, baked goods, confections, and pharmaceuticals sometimes have glycerin incorporated into their formulas. However, glycerin, unlike sugar, is not a classic carbohydrate. For this reason, companies eager to make low-carb claims use glycerin, sometimes as a substitute for sugar, but it also has many other valuable properties.
Glycerin belongs to a special category of carbohydrates called polyols. A polyol is an organic compound containing multiple hydroxyl groups, meaning that its chemical description includes an OH, because it contains an oxygen atom bonded to a hydrogen atom. Polyols are low-calorie sugar replacers with a clean, sweet taste and are approved for food. Among the polyols that we eat are: erythritol, hydrogenated starch, hydrolysates, isomalt, lactitol, maltitol, mannitol, sorbitol and xylitol. Erythritol, chemical formula C4H10O4, for example, is a sugar alcohol that is considered safe as a food additive in the United States and throughout much of the world. It was discovered in 1848 by Scottish chemist John Stenhouse, and was first isolated in 1852. It occurs naturally in some fruits. When used to replace sugar, polyols cause smaller increases in blood glucose and insulin levels than do sugars and other carbohydrates. Therefore, snacks sweetened with polyols may be useful.
Like sugar alcohols, glycerin tastes sweet, but it is not metabolized as sugar in the body, and doesn’t cause a rise in blood sugar. For that reason, it is sometimes used as a sweetener in foods marketed to diabetics and low-carb dieters.
Kashrus of glycerin
Glycerin is perhaps the most kosher-sensitive ingredient that any company can have. There is no way to test chemically whether the glycerin is manufactured from an animal, vegetable or mineral source, and non-kosher glycerin produced from animal fat is plentiful and often less expensive than are the other varieties. To compound the problem, as bio-diesel and other processes using vegetable oil have increased, less vegetable oil is available for the production of glycerin and this is being replaced by increasing the amount of animal fat used to manufacture glycerin.

Kosher glycerin is generally derived from vegetable oil, although it can also be chemically synthesized from petroleum. It is claimed that vegetable glycerin was originally discovered accidentally more than two centuries ago, by heating a mixture of olive oil and lead monoxide. But it became economically and industrially significant only in the late 1800s, when it was first used to make dynamite. Until that point, all glycerin was manufactured from animal fat.
Much of the kosher, vegetable-based glycerin is made from triglyceride-rich vegetable fats, such as palm, soy or coconut oil, and usually comes from countries like Malaysia and Indonesia that have an abundance of coconut and palm trees, although some kosher vegetable glycerin is made in the United States. Supervisors of kosher glycerin production need to oversee that the equipment used to produce it and the trucks and ships used to ship it in bulk are used only for kosher product or are koshered before use.
As with almost any substance, a small number of people have sensitivities or allergies to glycerin, and it can be toxic, if consumed in sufficient quantities. But, in its typical food uses, predominantly as a safe method of keeping foods fresh or as a low-glycemic sweetener, glycerin is generally safe. It is not, however, calorie-free.

This entire preamble was to provide background to an event that happened when I made a random kosher inspection of a factory several years ago. The company, which we will call Quality Bakery Products, was a manufacturer of wholesale products for the bakery and dairy industries, such as fruit mixes and toppings, glazes, maraschino cherries, fudges, etc. Thus, the fruit flavors in your yogurt, the fudge on your cookies, the fruit mixes in your fruit cakes may have originated in this factory. They did not produce retail sizes; everything was packed only in gallons, tubs and drums.

On that particular visit, I discovered a partially used drum of glycerin, without kosher markings. Glycerin was not a product that the company ordinarily used in their products and was not listed as an approved raw material by the hechsher. I was fairly certain that this glycerin was from non-kosher animal sources, and indeed, a small amount of research proved that I was correct. Since glycerin has a sweet taste and was certainly not bateil, the product or products manufactured with this glycerin were unquestionably treif.

Why did the company order glycerin? In what was it used? And where was it sent?

Within a short period of time, I was able to unravel what had happened. A new customer, a donut manufacturer that we will call "Diamond Donuts," contacted Quality Bakery with a large order for a donut glaze. Diamond Donuts had very specific requirements for the glaze – including glycerin as an ingredient. Presumably, Diamond Donut wanted glycerin in its glaze because it is sweet, syrupy and keeps the donuts fresher without any requirement to mention the nasty word "preservatives" on the label.

The sales staff accepted the order, the manufacturing department placed it on the schedule, sending on to the purchasing department the ingredient requirements that were not in house. The glycerin was ordered. No one at Quality Bakery picked up on several obvious errors they had made. For example, they were required by contract to contact the hechsher before purchasing new raw materials or changing suppliers, and glycerin was not an ingredient listed on their approved list.

The distributor through whom they ordered the glycerin sent them the least expensive product he had in stock, which happened to have been animal-derived glycerin. The ingredient was used, an entire container of drums of glaze was produced and was on the highway to Diamond Donuts by the time I discovered the problem. I was able to contact the rabbis at both hechsherim, Quality Bakery and Diamond, and the mashgiach who handled Diamond Donuts, to alert them that the glaze marked kosher was indeed very treif. The glaze and the leftover drum of glycerin were both destroyed, and many, many neshamos were fortunately saved from mistakenly eating treif donuts.

What is the moral of the story? For one, that hechsherim should have tighter controls on their companies. There should be a system in place so that new raw materials are not used without having the mashgiach sign off that they have been checked for kashrus concerns, just as these materials are checked for safety and efficacy.

For another, they should make sure that all key personnel at their companies fully understand the reasons for, and the details of, their kosher program. Included in the granting of the hechsher should be a periodic, scheduled meeting with all decision-making plant personnel, including the plant manager, production managers, purchasing agents, and the quality assurance staff, to guarantee that they all understand the responsibilities of a kashrus program.

And that we should all daven daily that we do not eat anything non-kosher.

This Shiur is published also at Rabbi Kaganof's site
Rabbi Yirmiyohu Kaganoff
Was the Rabbi of the Young Israel of Greater Buffalo, the Congregation Darchei Tzedek and also served as a dayan on the Beis Din of Baltimore. Now is a Rabbi in Neve Yaakov, Jerusalem. His Shiurim and Q&A can be found on his site:
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