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Many new-borns are fed with substitutes of breast milk. These products undergo several heat treatments, necessary to insure their microbiologic safety but probably modifying their organo-leptic properties. High temperature can damage milk proteins and form Maillard reaction prod-ucts with lactose. Microfiltration – to replace the heat treatments for a milk debacterization – combined with a soft spray-drying is currently an alternative little exploited to produce infant formulas (IFs) although microbiologically safe. The aim of this study was to determine the im-pact of such processing route on the organoleptic properties of the IFs. Three experimental IFs were manufactured at a semi-industrial scale, from fresh bovine skimmed milk: one with no heat treatments (T-), one with one moderate heat treatment (T+) and another one with successive and higher heat treatments (T+++) such as in industries. Sensory evaluations were performed by a panel of 50 untrained adults to characterise overall sensory differences (triangular tests) and the organoleptic properties (check-all-that-apply (CATA) de-scription) of the 3 experimental IFs, in comparison with 2 commercial ones (Blédilait, Guigoz). Volatile organic compounds (VOCs) contained in T- and T+++ were extracted with the solvent assisted flavour evaporation technique. The water phase was extracted with dichloromethane and concentrated in Kuderna-Danish apparatus. Samples were analysed by gas chromatography – electronic ionisation – mass spectrometry (GC-EI-MS), equipped with a polar capillary DB-WAX column to perform VOCs identification and relative quantification. Significant sensory differences were found in the triangular tests, between the experi-mental/commercial IFs, T-/T+++ and the both commercial brands. The CATA method supplied a global description of the 5 IFs, with 20 descriptors ticked by the panellists – related to colour, texture, taste, odour. A principal component analysis (PCA) was performed on quotations fre-quencies for each descriptor: there was a clear difference between off-flavour and pleasant de-scriptors. Another PCA shows an opposition between Guigoz – close to off-flavour descriptors – and the 4 other IFs – near to pleasant ones (“sweet”, “dairy”, “fat”, “butter”). These 4 IFs could be discriminated: T+++ was close to the same descriptors as Blédilait, as T- was with T+. Around 40 VOCs belonging to various chemical classes were identified. They are similar to T- and T+++, but in different proportions. These VOCs have olfactory connotations bound to a “fat in-mouth” sensation, “grass” and “fish” odours. A simple and saturated aldehydes group (pentanal, hexanal) comes probably from lipid oxidation, with a formation of hydroperoxides altering food flavour. Decomposition of these peroxides drives to a complex mixture of second-ary products (aldehydes, ketones…). VOCs quantities found in the IFs are in the range of the commercial ones. The IFs produced by different processing routes were different from a sensory point of view, with the less treated IF characterised by pleasant descriptors. The VOCs characterisation con-firms some flavour differences between the both experimental IFs and reveals presence of alde-hydes coming from the lipid peroxidation, which is commonplace for such IFs. Overall, these experimental IFs with a minimal processing route fit well withn IFs market, from a sensory point of view.

How do infants react to sweetness before the age of two? How is it different for the other primary tastes?. ILSI Europe Workshop “Dietary Sweetness, is it an issue"

International audience; Introduction: Gustatory evoked potentials (GEP), detected in response to an intermittent stimulation of the gustatory receptors by a primary flavor, are a reliable and safe record of the human gustatory function. We previously highlighted the modifications of GEP in response to saccharose stimulation by the concentration of the saccharose solution and its hedonic sensation. Fatty taste might be considered as the sixth primary flavor. We aimed to demonstrate that GEP in response to fatty taste stimulation do exist, and to compare these GEP with the GEP in response to saccharose and salty taste.Methods: Healthy and voluntary male subjects were included. Each subject underwent six GEP recording with different taste solutions: 5g and 20g of saccharose per 100mL of water, 0,5g and 2g of NaCl per 100mL of water, 0.25% and 1% linoleic acid solution. GEP were recorded from 9 cortical sites with EEG sensors: Cz, Fz, Pz, C3, C4, F3, F4, Fp1 and Fp2 of the 10/20 system.Results:We already included 12 subjects. We recorded GEP in response to the two concentrations of linoleic acid, like as saccharose and salt stimuli. GEP in response to saccharose stimulation had shorter latency and higher amplitude than fatty or salty taste. Contrary to salty and fatty stimulation, saccharose solution strongly activated the bilateral orbito-frontal cortex.Discussion/Conclusion:Recording GEP in response to linoleic acid stimulation shows that it exists gustative receptors which response to fatty taste. So, it is a strong argument to say that fatty taste can be considered as the sixth primary flavor.

Salivary proteins and bitterness acceptance in infants: an intringuing link[u][/u]. 9. European symposium on saliva

Fat perception received recent interest, but fat preference in human infants is a matter of debate. The objective here was to investigate fat and taste preferences in the same infants (N= 66) at 3, 6 and 12 months. Preference for a fat solution (sunflower and rapeseed oils mixed with soy lecithin) and for taste solutions (sweet, lactose; salty, NaCl; bitter, urea; sour, citric acid; umami, sodium glutamate) was evaluated. The same method was applied at each age. Mothers and their infant participated in 2 videotaped sessions, during which the 5 taste and fat solutions were assessed in a balanced order. For each taste, 4 bottles (water, tastant, tastant and water) were presented by the experimenter.Twoglobal indices were calculated to represent acceptance of the tastant relatively to water (W), based on ingested volumes and on facial expressions. At 3 and 6 mo, the fat solution was as consumed as W; but less than W at 12 mo; at all ages it elicited ‘negative’ expressions. For taste solutions, at 3 mo the sweet solution was more and the bitter one wasless consumed thanW;the bitter and the sour solutions elicited ‘negative’ expressions. At 6 and 12 mo, the sweet and salty solutions were more consumed than W and elicited ‘positive’ expressions; the bitter and sour solutions elicited negative expressions. Infants were indifferent to the umami solution. These findings are in accordance with the literature on taste preference but the indifference or rejection of the fat solution raise questions about an ‘innate’ preference for fat. The olfactory component of fat might be involved in this rejection.