Understanding fat, proteins and saliva impact on aroma release from flavoured ice creams

The release profile of fourteen aroma compounds was studied in ice cream samples varying in fat and protein, both in level and type. In vitro aroma release was monitored by solid phase micro-extraction gas chromatography using an innovative saliva reactor, which imitated human chewing under temperature control. The results showed that the effect of the fat type on aroma release was smaller than that of fat level. Ice creams with low fat level released more hydrophobic aroma compounds than ice creams with high fat level. At low fat level more aroma compounds were released from ice creams with lower protein content. At high fat level a small increase of aroma release was observed by the addition of saliva, which was explained by a salting out effect, due to the presence of proteins and salts in the saliva. These findings confirmed that the interactions between salivary proteins and aroma compounds occurring in aqueous solutions are not observed in emulsions

A saliva reactor to mimic in-vivo aroma release from flavoured ice-creams

The aim of the present study was to develop a saliva reactor allowing temperature control and the addition of human saliva in order to follow the release of five aroma compounds from different ice creams. The developed method was a useful tool to mimic the in-mouth process by taking into account sample quantity, mouth volume, temperature, salivary flux, and mastication. The reactor was fit with solid phase micro-extraction for gas chromatography allowing data collection similar to nose-space sam-pling. Different ice creams were assessed, with varying fat types and levels, and protein levels. The results showed that the effect of saliva is relatively low and only observed at the higher fat level. Also the effect of the fat type was smaller than that of the fat level. The ice cream with a low fat level released more hydrophobic aroma compounds than the one with a high fat level. The ice creams with both low fat level and low protein level, showed the highest release of aroma compounds. Less added proteins led to less interaction with the aroma compounds and increased their rate of release from the aqueous to the vapour phase. Overall, an innovative tool was provided to guide food industries to reformulate ice creams answering nutritional recommendations in line with consumer demands

Capturing the impact of oral processing behaviour on consumption time and dynamic sensory perception of ice creams differing in hardness

Little is known about the oral processing behaviour of ice creams for which the quantification of oral manipulations remains challenging. The impact of oral processing behaviour on dynamic sensory perception of ice creams has not been reported previously, although ice creams are anecdotally known to be consumed following different oral processing strategies. The aims of the study were (1) to compare different methodologies to characterise oral behaviours applied during consumption of ice cream, and (2) to understand how oral processing behaviour influences dynamic sensory perception of ice creams. Oral processing behaviour of ice creams was characterized by self-reporting and video recording of n = 103 consumers. Most consumers applied either tongue movements or combined tongue and jaw oral behaviours. The video recording was clearly better than self-reporting in capturing the actually displayed eating behaviour of ice creams. Consumption time was prolonged considerably when ice cream hardness increased or when oral behaviour was changed during Temporal Dominance of Sensations (TDS) evaluations. When ice creams were consumed by letting them melt in mouth, dominance of sweetness and firmness were significantly prolonged. When ice creams were consumed by chewing, dominance of fruity aroma and coldness were significantly prolonged. We conclude that (1) eating behaviour of ice creams is captured better by video recordings than self-reporting and that (2) oral processing behaviour considerably changes dynamic texture and flavour perception of ice creams. This highlights the importance of controlling oral processing behaviour when quantifying sensory properties of ice creams.</p