Yogurt Maker: Yogotherm vs. Jug Cooler

November 2009. We review two insulated containers for making yogurt; the Yogotherm and a Jug Cooler. The Yogotherm comes out a solid winner, but you can get decent, if not runny, results with a jug cooler.

Yogurt Fermentation

There are a number of ways to ferment yogurt. Being thermophilic, yogurt culture needs to keep warm while it ferments. Many yogurt makers plug in and require electricity. We prefer passive or insulated fermenters; those which don't require electricity. Passive yogurt fermenters rely on very good insulation plus the heat generated by the fermentation process to maintain optimal temperature for 6 hours or so. Click images to enlarge.

Meet the Yogotherm

The Yogotherm (which you can buy in our store or online) is designed for making yogurt. The pros and cons are:



  • Excellent insulation.
  • Removable inner container is easy to clean.
  • Produces excellent results; thick yogurt in little time.
  • Flavors are excellent as optimal temperature is maintained.


  • A little expensive.

As you probably noticed, we test most of our products before we sell them. We've now made yogurt many times with our Yogotherm and we love it. We decided to compare a lower-cost option; the generic jug cooler.

The Jug Cooler

Rubbermaid 1/2 Gal Jug CoolerRubbermaid 1/2 Gal Jug CoolerThe 1/2 gal jug cooler has a similar capacity to the yogotherm, but costs only around $15. If you compare the thickness of the walls, you can see that the jug cooler does not have nearly as much insulation as the yogotherm. To compensate, we wrapped a large bath towel around the jug cooler and secured it with a bungee cord.
Jug Cooler Plus Extra InsulationJug Cooler Plus Extra Insulation We made a batch of yogurt in the jug cooler using the same yogurt recipe. Although we added the towel for extra insulation, the top of the milk still cooled too much. When the yogurt was done, the milk on the top was runny, whereas underneath it was thicker. With the yogotherm it comes out thick all the way through. We stirred it up and scooped into two quart containers. The flavor was almost as good, but the culture seems happier in the yogotherm. Overall we were able to get good results, just not as good or as easily as we do with the yogotherm. The jug cooler has the following pros and cons: Pros:

  • Inexpensive.
  • May be easier to find.


  • Requires additional insulation and results still not as good as yogotherm.
  • Harder to scoop and clean out yogurt.
  • No separate container for yogurt.

Yogurt in Jug CoolerYogurt in Jug CoolerInside Jug CoolerInside Jug Cooler


In summary, the Yogotherm is a superior tool for making yogurt without having to buy another plug-in kitchen appliance. You can get decent results with something like a jug cooler if you are willing to do more work, but it is harder to keep that yogurt culture happy and warm.



While we still offer the yogotherm, for those of you interested in a dual purpose device, we now sell a stainless steel insulated growler.

It absolutely rocks for keeping that delicious craft ale chilly. It is also pretty handy as a yogurt maker, particularly if you place it inside of a picnic-sized cooler or wrap it in additional insulation. Placing the stainless growler in a preheated picnic cooler overnight, I have experienced overnight temperature drops of only a few degrees.