Aroma-retention capacities of functional whey protein aggregates: Study of a strawberry aroma in solutions and in fat-free yogurts.

The aroma-retention capacity of functional whey protein aggregates (WPA) was compared to that of native whey protein isolate (WPI) in aqueous solutions and in fat-free yogurts. The retention of aroma compounds, constituting a model strawberry aroma, was evaluated by calculating gas-matrix partition coefficients using headspace gas chromatography (HS-GC). The retention capacity of WPA differed from the one of WPI for three out of seven aroma compounds detected in HS-GC. Incorporating WPA in fat-free yogurts tended to decrease the release of hydrophobic aroma compounds such as 2-nonanone or methyl-cinnamate. The magnitude of the differences between the partition coefficients of yogurts enriched in WPI or WPA was lower than in aqueous solutions, which is likely to be due to the higher complexity of the food matrix and potential interactions with other ingredients. Overall, the different aroma-retention capacities of native WPI and functional WPA are likely to lead to unbalanced aroma, especially in fat-free dairy products.

Higher Pericyte Content and Secretory Activity of Microfragmented Human Adipose Tissue Compared to Enzymatically Derived Stromal Vascular Fraction.

Autologous adipose tissue is used for tissue repletion and/or regeneration as an intact lipoaspirate or as enzymatically derived stromal vascular fraction (SVF), which may be first cultured into mesenchymal stem cells (MSCs). Alternatively, transplant of autologous adipose tissue mechanically fragmented into submillimeter clusters has recently showed remarkable efficacy in diverse therapeutic indications. To document the biologic basis of the regenerative potential of microfragmented adipose tissue, we first analyzed the distribution of perivascular presumptive MSCs in adipose tissue processed with the Lipogems technology, observing a significant enrichment in pericytes, at the expense of adventitial cells, as compared to isogenic enzymatically processed lipoaspirates. The importance of MSCs as trophic and immunomodulatory cells, due to the secretion of specific factors, has been described. Therefore, we investigated protein secretion by cultured adipose tissue clusters or enzymatically derived SVF using secretome arrays. In culture, microfragmented adipose tissue releases many more growth factors and cytokines involved in tissue repair and regeneration, noticeably via angiogenesis, compared to isogenic SVF. Therefore, we suggest that the efficient tissue repair/regeneration observed after transplantation of microfragmented adipose tissue is due to the secretory ability of the intact perivascular niche. Stem Cells Translational Medicine 2018;7:876-886.