Writing in the journal Appetite, Keri McCrickerd, Lucy Chambers, and Martin Yeomans report that subtly increasing the viscosity of a drink increased its perceived thickness, and led women to consume significantly less of the drink and still feel satisfied.
“This builds on previous work suggesting that increasing the viscosity of a drink increases the extent to which it is expected to be satiating and suggests that such expectations can influence actual eating behavior,” they wrote.
“The majority of participants consumed all of the drink that they served themselves, indicating that the reduced intake of thicker drinks was because female participants poured out less of these versions, which is in line with research suggesting that pre-meal expectations of satiation and satiety are important determinants of meal size.”
The research follows earlier reports from the same group which could be of particular use in low calorie and weight management foods, which can often cause problems to consumers because they often do not feel full after consumption (Flavour, 2012, 1:20).
Study details
McCrickerd and her co-workers recruited 24 men and 24 women to participate in their study. The participants attended four test days in the lab that began with a fixed-portion breakfast. They returned two hours later for a mid-morning drink in four sensory contexts: thin and low-creamy; thin and high-creamy; thick and low-creamy; thick and high-creamy.
Results showed that women, but not men, consumed less of the thick drinks. Surprisingly, and in contrast to other studies, the men consumed the same amount of the four drinks regardless of sensory context.
While the addition of creamy flavor did not appear to affect intakes, the participants did perceive the thicker drinks to be creamy.
Despite the differences in intake for the women compared to the men, the researchers did not find any difference between the participants in terms of hunger and fullness for any of the different drinks.
Women vs men
McCrickerd and her co-workers noted that the men in this study consumed on average 451 grams of the drinks – the capacity of the glass, and about 100 grams more than their female counterparts.
“This suggests that for many of the male participants, their desired portion size was probably greater than the maximum amount of drink that could be held in the glass, and in order to consume this amount they had to pour a second helping of the drink,” they suggested. “Perhaps this portion size cue limited the influence of satiety expectations on self-selection in the male participants more than the female participants, whose average serving size was much less than the capacity of the glass.”
Eating speed
Texture may also play a role in our feelings of fullness due to effects on the speed of consumption and bite size. Recent research from Ciaran Forde at the Nestlé Research Center in Switzerland, suggested that the textural properties of foods has a direct influence on consumers' eating behavior and food intake.
“Previous studies suggest that oral processing characteristics such as large bite size, low number of chews and low oro-sensory exposure contribute to the low satiating efficiency of these foods," the team behind the study said.
"The evidence from these studies provides new insights into how different foods may impact eating behaviors, such as bite size and chewing time. These, in turn, can also impact feelings of fullness and food intake," explained Forde.
Source: Appetite
Volume 73, Pages 114–120, doi: 10.1016/j.appet.2013.10.020
“Does modifying the thick texture and creamy flavour of a drink change portion size selection and intake?”
Authors: K. McCrickerd, L. Chambers, M.R. Yeomans