The study, by Danish researchers, combined hedonistic sensory ratings with post-ingestive sensation ratings, to give what they suggest is a more holistic system of food satisfaction scoring.
For this study the researchers trialled four different apple-cherry-flavoured drinks: sweetened with glucose; sweetened with stevia; sweetened with stevia and with added lime flavour; and sweetened with stevia, with lime flavour and added fibre, in the form of beta glucans.
Sixty-six members of a Danish consumer panel were recruited as subjects, and given all four drinks to taste in random order over four sessions, spread out over four days. The subjects first tasted and rated a 25ml sample, then were required to consume 250ml of the drink in each session, and complete a survey on how they felt at 10-minute intervals up to 40 minutes after ingestion.
Stevia beats sucrose?
While the sucrose-sweetened drink had an average overall liking score of 6.4 and a sensory satisfaction score of 6.5, the stevia-sweetened drink had scores of 6.7 and 6.4 respectively. All scores were on a nine-point scale, with 9 being the optimal score.
In contrast the stevia and lime flavoured drink scored 6.0 for both liking and sensory satisfaction, while the stevia, lime flavoured and fibre drink scored 5.8 and 5.5 respectively. Notably the drink with fibre scored a full point lower for appearance than the other varieties – 5.7 compared to 6.7 – and 1.4 points lower for texture than the next lowest – 5.3 against 6.7.
“One explanation for the similar hedonic ratings [between the sucrose- and stevia-sweetened drinks] is the high content of Rebaudioside A (>75%) in the stevia used in the present study. Stevia extracts with a high Rebaudioside A content deliver a cleaner sweet taste with less bitterness and liquorice notes compared to extracts with a lower Rebaudioside A content,” wrote the study’s authors in their paper published in the journal Food Quality and Preference.
They also noted the addition of lime flavour – originally intended to mask negative stevia characteristics – resulted in lower ‘‘liking of odour”, ‘‘drinking pleasure” and ‘‘liking of aftertaste” ratings.
“These results show the relevance of a more detailed description of consumers’ hedonic appreciation of sensory characteristics, as no differences were found on overall liking in the present study,” wrote the authors.
Fibre fullness from sensory cues, not satiety
Regarding the lower scores of the fibre drink, the researchers noted that the lower appearance scores could have affected overall liking.
The fibre drink also resulted in lower sensory scores for “hunger” and higher ratings for “fullness” and “replacement of snack”. But the researchers noted these effects were reported immediately after drinking, “suggesting that the appetite altering effect probably was more related to the sensory cues rather than to the post-ingestive sensations perceived at a later stage after intake”.
“No significant effect of fibre addition was seen 20–40 minutes post intake. A potential explanation is that the fibre content in [the drink] was too low to cause effects on gastric emptying, mentioned in the introduction,” they wrote.
“From a scientific point of view the present study showed that hedonic sensory drinking experience was the most important driver of food satisfaction, and that post-ingestive sensations contributed to food satisfaction as well,” the researchers noted in their conclusion.
“The overall hedonic experience was studied through the well- known measure of overall liking and sensory satisfaction. Sensory satisfaction was found to be more discriminative than overall liking, and to better reflect specific liking properties,” they added.
Source: Food Quality and Preference
Published online ahead of print, doi: 10.1016/j.foodqual.2017.01.005
“Integration of the sensory experience and post-ingestive measures for understanding food satisfaction. A case study on sucrose replacement by Stevia rebaudiana and addition of beta glucan in fruit drinks”
Authors: Andersen, B.V.; Mielby, L.H.; Viemose, I.; Bredie, W.L.P.; Hyldig, G.