I’ve had the question posed recently asking whether the Wonder Junior Hand Mill has any aluminum in it. In a nutshell, yes, it does, but at the same time, there is no measurable transfer of any alloy or aluminum from the auger drive to the food.
The auger drive that guides the grain into the grinding burrs is made out of a composite alloy that does have some aluminum in it. The reason this composite alloy was chosen is for its strength, durability, and the fact that it can be cast into a light, yet super strong corrosion resistant drive with no risk of food contamination. The grinding process of the mill takes place in the stone or stainless steel burr grinding plates (whichever are being used at the time), not in the auger drive. Because of this, there is no transfer of any alloy or aluminum from the auger drive to the food. The auger drive is magnetic attractive which shows there is very little aluminum in the alloy. Also since any aluminum transfer requires a heat or chemical reaction, even this slight amount would never be transferred into the flour since the grinding action comes after the grain passes through the auger drive area and into the stone / stainless steel grinding chamber. Because of this there is no measurable transfer of any alloy or aluminum from the auger drive to the food. The chance of getting aluminum into your body from using this mill would be less than simply touching a soda can or a public stair case railing or opening the door of your car.
Take for example, a typical soda can. There, the acidic drink sits in contact with a can made of almost entirely of aluminum (not a small percentage like the auger). It remains in contact with the aluminum for days, weeks, months, or even years. Even then, the evidence of contamination from aluminum is not overwhelming. Now compare that with the auger. Your dry grains come in contact with the mill seconds before they are ground. At the most, the grain touches the auger for a few minutes as you give your arms a break from grinding the last 10 cups of flour. There is no heat buildup around the auger, and there are no chemical reactions going on while your wheat momentarily touches the auger.
Likewise, the main body, also made from aluminum on the Wonder Junior, is not a concern since it is coated with a food grade enamel. However, even if it were to chip, it would be no different than the auger. The grains only rest in the hopper for seconds and move on through.
So, in a nutshell, there’s really nothing to be concerned about. Relax, enjoy your bread, and feel great knowing that you produced a healthy, all natural loaf of bread, better than anything you’ll ever find in a store!