Capillary electrophoresis analysis of sialyloligosaccharides in milk of different species

Sialyloligosaccharides (oligosaccharides containing one or more residues of sialic acid) are relevant components of human milk, which have been quite well studied for their prebiotic effect and their capacity in stimulating the immune system. Since oligosaccharides from milk of non-human mammals received so far less attention, the aim of this work was the application of capillary electrophoresis (CE) for the analysis of sialyloligosaccharides in milk of different species, to possibly identify potential sources of oligosaccharides to use as health promoting ingredients in functional foods. Mare milk (3 samples), ass milk (3 samples), goat milk (2 samples) and cow milk (10 samples), at different stages of lactation, were analysed in comparison to 2 samples of human milk. Samples were frozen at -20°C immediately after collection, thawed over-night at 4°C before analysis, defatted and deproteinized. A recent CE technique using the MEKC mode with direct detection at 200 nm was applied to resolve and quantify 3 of the most dominant sialyloligosaccharides of human milk. Commercial standards of 3-sialyllactose (3-SL), 6-sialyllactose (6-SL) and disialyllacto-N-tetraose (DSLNT) from 39 to 2500 μg/mL were used to create linear calibration curves (R2 from 0.9967 to 0.9997), with coefficients of variation from 3 to 10%. Analysis of non-human milk samples confirmed differences among species, individuals and between stages of lactation: DSLNT, which was the most abundant compound in human milk (455-805 μg/mL) was missing in most of the samples. In most cases 3-SL showed to be the most concentrated of the analytes we quantified, with values ranging from 12 to 77 μg/m

Effect of differently processed fruit preparations on the quality characteristics of strawberry yogurt

Advancing on preliminary research, the aim of this work was to further study how partial air dehydration applied to fruit pieces before freezing, alone or in combination with osmo-dehydration, could improve not only quality of strawberry slices used in yogurt preparation but also yogurt characteristics. Raw (NT), air-dehydrated (D), and osmo-air-dehydrated (OD) strawberry slices (cv. Tethis) were heat-treated, and then added (final concentration = 15%) to plain yogurt. Chemical, physical, and sensory analyses were carried out on the products after 15 and 30 days of storage at +4degreesC. D and OD ingredients showed better texture than NT strawberry slices. Analyses, carried out during the shelf-life of fruit-yogurt, showed a dynamic exchange of sugars between fruit pieces and yogurt. Yogurts containing the dehydrated fruit pieces were more viscous than those with fresh strawberry ingredients, particularly at the end of shelf-life (30 days). Relationship between sensory response and objective texture indexes was found

Assessing wine sensory attributes using Vis/NIR

25 Páginas, 8 Figuras, 6 TablasThe quality of wine involves the presence and intensity of many flavors and nuances. The assessment by tasting panels of the sensory quality of wine and by measuring the intensity of their attributes or defects is more difficult than assessing the global score of wine quality, which is a single value for each wine. This research focused on the feasibility of the visible and near-infrared spectroscopy for assessing wine sensory attributes. Predictive models of sensory attributes such as positive and negative for red and white wines have been developed, based on their spectra and reference values from a specialized tasting panel. The results indicate that the technique is feasible for predicting some of the most characteristic sensory attributes of red and white wines such as Flavor intensity, Astringency, Color intensity, Length, Persistency, Pleasantness and Balance. Their correlation coefficients of validations were about 0.9 in most cases. The technique was also suitable for predicting some important defects such as Oxidation, Unclean, Ethyl acetate and Acetic acid. The main potential use of this technique is for contrasting or confirming the assessment of wine for the positive and negative sensory attributes, determined by the sensory analysis of tasting panels. This can be particularly useful in cases where there is discrepancy in the assessments of a sensory panel. It is reasonable to consider the possibility of tuning the technique for detection in routine analysis of some negative attributes.Peer reviewe