Identifying and Differentiating Various Brands of Potato Chips

Project Team:

* Steven Wallace, Surface Metrology Lab of Worcester Polytechnic Institute, BSChE, Virginia Tech ’02
* Franco Pedreschi, Dept of Food Science and Technology at Universidad de Santiago de Chile, PhD, Pontificia Universidad Catolica de Chile ‘00
* Prof. Christopher A. Brown, Surface Metrology Lab of Worcester Polytechnic Institute, PhD

Goal/Objective:

Using a scanning laser profiler determine the range of relative areas of various brands of potato chips that can identify each and differentiate between them.

Rationale:

The surface metrology lab here at WPI has broken the barriers between surface metrology and food science by exploring projects in the food science industry such as: working in collaboration with Virginia Tech’s food science department to examine various fruits along with completing its own Chocolate Forensics project. Continuing in this pursuit in this area is Identifying and Differentiating Various Brands of Potato Chips. The relative area of a potato chip is a key factor in how much oil and salt each chip will hold, and ultimately, how the chip will taste. This, however, has been an overlooked detail in their production. This work may be the introduction and exploratory project to change this.

Image of potato chips from the brand, Lays

Image of potato chips from the brand, Price Chopper

Image of potato chips from the brand, Wise

Approach:

Using a scanning laser microscope (SLM) the relative areas were found for 10 of each brand of potato chip. Images were taken of each (examples shown above) and the relative areas were plotted against each other to identify each brand of potato chip. A scale-based f-test was then performed on the data taken by the SLM to determine the scale of observation at which we can differentiate between each brand of potato chips.

Results:

Lays had the tightest range of relative area across 10 chips of ~3.3 to ~4.0. Price Chopper had a range of ~3.3 to ~4.8. Wise had a range of ~3.5 to ~4.8 (minus one possible outlier at 3.0). The scale-based f-test showed that Lays and Wise could be differentiated with 95% confidence at a scale of observation of 104 to 105 um2. The f-test also showed that Price Chopper brand potato chips could not be distinguished from either the Lays or Wise brands. Image analysis is still in progress and is being performed by Franco Pedreschi.

Plot of Mean Square Ratio versus Scale of Observation for Lays and Wise. The black lines across the graphs represent a 95% confidence interval.

Plot of Mean Square Ratio versus Scale of Observation for Price Chopper and Lays.

Plot of Mean Square Ratio versus Scale of Observation for Price Chopper and Wise.

Follow-up/Future work:

Future work can be done on measuring different brands or types of chips, such as baked or tortilla chips, and comparing to the data already collected. A further analysis could be conducted on discovering how the relative areas plays a role in how the chips absorb and hold oil and salt.

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Last modified: September 13, 2007 09:40:38