Ordinarily, when food companies are developing new low-fat potato chips, they rely on human taste-testers to assess the chips’ texture. Utilizing such people can be expensive and highly subjective, however, which is why scientists have now created an objective lab-based testing procedure.
The system was first envisioned by food scientist Stefan Baier and University of Queensland chemical engineer Prof. Jason Stokes, when Baier was employed at PepsiCo – he’s now Head of Food Science at food technology firm Motif Ingredients.
Utilizing an assortment of instruments, the new procedure (known as in vitro oral processing) simulates and evaluates four stages in the eating of potato chips containing varying amounts of vegetable oil. There’s the first bite, when the chip is initially broken by the teeth; comminution, when the resulting chip particles are broken down further and moistened by saliva; bolus formation, when enzymes in the saliva begin to digest starches in those now-smaller particles, causing them to form into clumps; and swallow, when those clumps are ingested.
“First bite,” for instance, is tested by mechanically measuring how much force needs to be applied to break the chip. Bolus formation, on the other hand, is assessed by measuring the hydration rate of chip particles as they form into a soft solid while placed in a saliva-like buffer solution.
Utilizing their new system, Baier, Stokes and colleagues developed a low-fat chip that was coated in a thin layer of seasoning oil, which itself contained a small amount of food emulsifier to give the chip a smooth, greasy texture. Human test subjects reported that the chip had a “mouth feel” similar to that of a full-fat chip, yet the coating in fact only boosted the low-fat chip’s oil content by 0.5 percent.
Source: American Chemical Society