|This scale is so advanced, it doesn’t include a display of its own. FAIL!|
Full disclosure: I have never used one of these smart scales. I’m sure the interactive part is nice for first-time cooks. I’m assuming the app helps keep track of the recipe steps and ensures ingredients aren't accidentally left out. However, all this technological overhead seems unnecessary. The key advantage of this product isn’t the app, Bluetooth transmitter, nor recipe database; it’s the scale. Cooking using a scale makes the process much easier. What’s holding most people back is the lack of weight conversions on most recipes.
Conversion from volume to weight is pretty easy. Food labels are usually a good place to start. Here’s a label from a container of almond butter:
The serving size contains the conversion, although you probably never noticed it before. Two tablespoons equals an ounce, which in metric is approximately 28 grams. In fact, the nutritional labels often base their serving size primarily on the weight (usually an ounce or 100 grams) rather than the volume. The volume measurement in this example, two tablespoons, is most likely an estimate. Let’s suppose a recipe calls for one cup of almond butter. There are 16 tablespoons in a cup. Therefore, you’d need eight ounces or 228 grams. Once you have the weight, you can update your recipe for the equivalent gram amount and use any regular food scale without the need for an expensive hydrophobic electronic tablet to accompany it.
Nutritional labels’ volume-to-weight conversions aren’t always accurate. Items where labels specify a very small serving size in comparison to the amount used in practice makes this method unfeasible. Heavy cream is a good example of this problem. Labels specify a tablespoon, but recipes usually call for much more. There’s a bigger chance for error scaling up from a tablespoon to cups. A better resource for common food items is the nutritional database run by Self magazine: http://nutritiondata.self.com/.
The drop down provides much better serving sizes with their volume to weight conversions.
As a last resort, you could measure the item yourself to get a best estimate. I had to do this for powdered erythritol. Liquids are usually more uniform. A basic rule of thumb is that most low-viscosity liquids are 242 grams per cup.
Most food scales are very accurate and do not require calibration. In case you’re wondering which one I use, it’s the OXO Good Grips Stainless Steel Food Scale with Pull-Out Display. I don’t like the way it displays US measurements using eighths of ounces rather than tenths, but this isn’t a problem for me since I always use metric. Word of warning: there’s a bug with some of these scales where they do not remember the last unit selected. Mine always defaulted to US units whenever it was powered on. Oxo sent me a replacement when I called about the issue.
Using ingredient weights is convenient because you can pour the contents from its container into the bowl on the scale using the readout to determine how much to use. Weights are always more accurate since volume measurements can be affected by moisture or air content. For example, sifted flour vs. packed flour.
I see no reason to buy an expensive scale that locks you into a proprietary app recipe database and forces you to use a tablet to make measurements. Buy an inexpensive “dumb” food scale and simply update your recipes to include gram measurements.