For my second year project I had to do nutritional analysis of a chosen product. The food product that I chose was a protein bar. After conducting the analysis it was found that the product only contained about 15.6 grams of protein / 100 g product while the nutritional label claimed 35.6 grams of protein / 100 g product.
The method used for this protein analysis was the automated Kjeldahl method using Gerhardt’s Kjeldahl digester and analyser. Nothing went wrong in any of the analysis steps, so I’m not sure why the results are so low compared to the protein content in the label. If it’s relevant the sugar content of the product is also very high compared to the nutritional label.
The only explanation I could think of was that they initially used a different method to detect the protein content, or that the company has reduced the amount of protein in the bar over time.
Is there other possible reasons behind this very low protein content detected?
I haven’t done that particular procedure, so, in lieu of a more helpful answer, let me just point out that it is entirely possible that they just plain old lied about the content.
Nutrition labels are not exhaustively tested. They are, at most, occasionally audited, and if, at that time, your product is found to have less than 80% or more than 120% of the expected nutrient, then the typical course of action is that the FDA asks you to reprint your labels on your next batch. That’s it. There are of course more actions the FDA could take, but they usually don’t.
Nutrition labels are, to a significant extent, an act of advertisement. They are made by the company, not made by the product. Nowhere is this going to be more true than for a product like a protein bar, where people base their purchasing decisions on the nutrition data. When an incentive to lie exists, people often do, especially when there’s money on the line.