14 DAY TRIAL // A new study carried out by the Monell Center found out that food texture is perceived differently, depending on individuals and the amount of a salivary enzyme they produce.
People have preferences when it comes to food and this is caused by an oral enzyme called salivary amylase.
Study lead author Abigail Mandel, a nutritional scientist at Monell said that “differences in starch perception likely affect people's nutritional status by influencing their liking for and intake of starchy and starch-thickened foods.”
Starch is part of our everyday diet, as it is found in wheat, corn, rice and potatoes and it represents between 40 and 60 percent of our caloric intake.
The amylase enzymes within the saliva break down starches into sugar molecules that are later absorbed into the bloodstream and influence glucose levels.
What the researchers discovered was that the changes that people perceived of starch consistency in the mouth depended on the activity of salivary amylase.
So, they measured enzyme levels and activity thanks to saliva collected from 73 subjects, by mixing it with a standardized starch sample before a sensor could assess the rate of the enzymatic break-down.
Next, the analysis of enzymes and proteins gave the amount and the activity of salivary amylase in the samples.
Afterward, the participants were evaluated during 60 seconds and rated the perceived breakdown of a starch sample in the mouth.
Senior author Paul A. S. Breslin, a Monell sensory geneticist concluded that when “taken together, this means that foods with different starch levels will be perceived very differently by people as a function of how much salivary amylase they produce.
“What may seem like a thick and resistant pudding or starchy food to some may seem noticeably thin in the mouths of others.”
This research could also prove helpful for better understanding metabolic diseases, if we admit that a higher quantity of salivary amylase gives a faster breaking of starchy foods, thus a higher post-meal blood glucose level.
“In today's state of food excess and refined starch ingestion, it is possible that high levels of salivary amylase contribute to the risk of insulin resistance and non-insulin dependent diabetes,” Mandel said.
Besides these findings the scientists focused on proving a genetic influence on salivary amylase activity, so they analyzed samples from 62 subjects and found out that one person's number of AMY1 copies (the gene that codes for salivary amylase) is linked to the amount and activity of their salivary amylase – an individual can have anywhere from 2 to 15 copies of AMY1.
“A link from genetic variation to enzymatic proteins to altered physiology to oral perception of textures is quite novel and provides a complete story,” added Breslin.
The study was reported in the journal PLoS ONE.