I want to give Waggin’ Train and others like them, a firm kick in the caboose.
Glycerin. You see it everywhere in dog treats. When you do, put the bag down and slowly step away. It could kill your pet.
Glycerin (aka glycerol or vegetable glycerin or glycerine) is a sugar and a filler. It’s classified as a humectant, which means it absorbs water or moisture. It’s included in pet treats – which are sold by net weight – so the manufacturer can sell you the weight in water. Glycerin binds the water so as to disguise the water as a solid treat or food, and inhibit mold growth. And if you see it on the label, there’s generally a lot of it present. To produce a soft, moist / semi-moist treat, glycerin generally makes up about 10% to 18% of the product. Glycerin is also about 60% as sweet as sugar so there’s some palatability benefit for the treat maker to include the stuff as dogs can taste sweetness.
Until recently, most glycerin for pet food was produced as a byproduct of soap making. It’s created when fat or vegetable oil is saponified. Today, a lot of glycerin that’s in food for animals comes from a much deadlier source. It’s a byproduct of biofuels.
There has been an extraordinary amount of glycerin coming into the market from biofuel production, since one gallon of biodiesel yields one pound of glycerin. This rate of production places tremendous pressure on the supply side of the glycerin market to find new uses for this product. Animal food is where it’s being dumped.[i]
What makes glycerin produced from biodiesel any different than that from soap? Plenty.
The production of glycerin from biofuels leads to significant amounts of residual methanol (wood alcohol) and sodium that remain in the glycerin. The US Food and Drug Administration (FDA) and the EPSA (Europe) are taking a hard look at this product given the nature of its contaminants.
Methanol (wood alcohol) is a flammable, poisonous liquid that’s also the raw material for making formaldehyde. It’s on the Community Right to Know List. Methanol is highly toxic, readily absorbed from all ways one can be exposed to it, and has narcotic properties. Ingestion can cause blindness and death. Lesser exposure causes blurry vision, headaches, and GI disturbances. Symptoms of exposure include headache, dizziness, confusion, abdominal pain, lung problems, weakness and coma.[ii]
Pet food makers that use glycerin from soap are trying to distinguish their products from those containing the poisonous glycerin from biodiesel. To do so, they’re now referring to their glycerin as “natural” glycerin. Natural, refined glycerin (derived from soap making) is generally recognized as safe (“GRAS”) though irritating to mucous membranes.
It’s wise to be cautious when seeing “natural” glycerin on a label though, as the production of crude glycerine from biodiesel is also categorized as “natural.”
Below is a list of some pet treats containing glycerin. At a minimum, it’s worth asking the manufacturer if they use human food grade glycerin, what company provides it to them and what country it comes from.
- Beggin’ Strips
- Beneful (Baked Delights and Snackin’ Slices)
- Bil-Jac (liver treats for dogs and Gooberlicious)
- Blue Buffalo (Blue Bits, Blue Bites, Blue Stix, Super Bars, Blue Bones, Wild Bites, Blue Wilderness Wild Bites)
- Blue Dog Bakery (Softies, Perfect Trainers)
- Buddy Biscuits (Soft and Chewy, Chewy Tricky Trainers)
- Busy Bones
- Canyon Creek Ranch
- Carolina Prime
- Cesar Treats
- Dentastix (from Pedigree)
- Good Bites (from Pedigree)
- Halo (Spot’s Chew)
- Milo’s Kitchen
- Pur Luv (Chewy Bites, Little Trix, Grande Bones)
- Purina Pro Plan (various treats including Roasted Slices)
- Real Meat Jerky Treats (Jerky Bites, Bitz, Long Stix, Large Bitz)
- Solid Gold (Beef Jerky, Turkey Jerky, Lamb Jerky, Tiny Tots)
- Waggin Train
- Wellness (Wellpet, Wellbites)
- Zukes (Hip Action, Natural Purrz, Jerky Naturals, Mini Naturals)
[i] Is ‘natural’ glycerin a good petfood ingredient? Greg Aldrich, PhD. Petfood Industry Magazine. January 2012, pp 52-53
[ii] A Consumer’s Dictionary of Food Additives, 7th Edition. Ruth Winter, M.S.