Internal scattering as an optical screening method to identify peeled potatoes giving rise to an excess of acrylamide

- Spatially-resolved spectroscopy to monitor acrylamide formation in potatoes.
- Non-destructive sensing of raw potatoes unsuited for high-temperature processing.
- Influence of acrylamide precursors on the scattering properties of potatoes.
- Optical detection to sort-out potatoes giving rise to excessive acrylamide formation.

The formation of acrylamide during the frying of potatoes is nowadays one of the major concerns of the potato-processing agriculture industry. Much research has been carried out to identify the acrylamide precursors in raw potatoes in order to minimize its formation during frying. Raw potatoes that give rise to an excess of acrylamide can currently not be detected in a fast, sensitive and non-destructive way. Therefore, we investigate the use of spatially-resolved spectroscopy to optically identify raw potatoes with high acrylamide precursors concentrations, on basis of their internal scattering properties. To obtain potatoes that induce high acrylamide concentrations, we stored the potatoes in a fridge at 4 °C. Measurements of the potatoes after different storage times (11, 15, 21 and 28 weeks), corresponding with different acrylamide concentrations in the French fries, show an evolution of the scatter pattern. Furthermore, when comparing the scatter properties at different wavelengths for potatoes giving rise to low (<600 ppb) and high (>600 ppb) acrylamide concentrations during frying, an optimized classification of the potato batches was obtained at 1444 nm. We can conclude that the internal scatter properties of peeled, raw potatoes can be used to monitor the acrylamide precursors, enabling a non-destructive exclusion of the potatoes that are not suited for French fries production.