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Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques were used to study the effect of four food additives, agar, alginate, lecithin and glycerol, at three different concentrations, 0.5, 1 and 1.5%, on the molecular structure of potato puree prepared from commercial potato powder. Vibrational spectra revealed that the amylose-amylopectin skeleton present in the raw potato starch was missing in the potato powder but could be fully recovered upon water addition when the potato puree was prepared. FTIR peaks corresponding to water were clearly present in the potato powder, indicating the important structural role of water molecules in the recovery of the initial molecular conformation. None of the studied puree samples presented a crystalline structure or strong internal order. A comparison of the FTIR and XRD results revealed that the additives exerted some effects, mainly on the long-range order of the starch structure via interacting with and changing -OH and hydrogen bond interactions.

This paper studies the applicability of extrusion-based 3D printing for constructing novel shapes from potato puree and the effects of four additives (agar, alginate, lecithin and glycerol) added separately at three concentrations (0.5, 1, 1.5%) on the internal strength, mechanical properties, microstructure and color of potato puree. The printability of the potato puree and the mixtures was assayed by examining the consistency of the extrusions and the stability and accuracy of the printed patterns. The results indicate that better printing was achieved at a nozzle height of 0.5 cm and a nozzle diameter of 4 mm, with concentrations of alginate and agar between 0.5-1.5% and 0.5-1%, respectively, providing the best printability and end-product stability, which was attributed to their respective high mechanical characteristics and specific mechanical energy (SME) values. Scanning electron microscopy (SEM) revealed that more convolutions were induced in the potato puree upon the addition of agar or alginate, which increased the puree stability. Three-dimensional printing did not significantly affect the surface color parameters of the final product. This study showed that the 3D printing process is a critical factor for initializing the production of customized healthy products.

International audienceThe development of flexible drug delivery systems that can be tuned as a function of the drug to bedelivered and of the target disease is crucial in modern medicine. For this aim, novel amphiphilic poly-(e-caprolactone)-g-poly(ethylene glycol) (PCL-g-PEG) copolymers with well-controlled design weresynthesized by thiol–yne photochemistry. The grafting density and the copolymer amphiphilicity wereeasily controlled via the reaction parameters: concentration, reaction time, PEG length and the molarratio between PCL and PEG or the photoinitiator in the reaction mixture. The self-assembling behaviorof the copolymers was studied and a correlation between the composition of PCL-g-PEG and thenanoaggregate diameter sizes (28 to 73 nm) and critical aggregation concentrations (1.1 to 4.3 mg L1)was found. The influence of copolymer amphiphilicity on the drug loading was evaluated with variousdrugs including anticancer drugs (paclitaxel, ABT-199), drugs to overcome multidrug resistance incancer cells (curcumin, elacridar), an anti-inflammatory drug (dexamethasone) and an antibacterial drug(clofazimine). Finally, the influence of amphiphilicity on curcumin release and toxicity towards MCF-7cancer cell lines was studied. The impact of the grafting density, PEG length and the overall EG/CL ratiois discussed in detail. Curcumin loaded PCL-g-PEG with lower EG/CL ratios and shorter PEG chainsshowed higher toxicity compared to their more hydrophilic counterparts

The effects of agar, alginate, lecithin and glycerol on the rheological properties of commercial potato puree were investigated and interpreted in terms of starch microstructural changes, and the applicability of the Cox-Merz rule was evaluated. Each additive was applied separately at two concentrations (0.5 and 1%). Microscopic observations revealed more swollen starch aggregations in lecithin and glycerol compared with those of potato puree and agar, consequently affecting the rheological properties of potato puree. All samples exhibited shear thinning non-Newtonian behaviour. Rheological measurements were strongly concentration dependent. At 0.5% concentration, additives exerted decreases in all the rheological properties of potato puree in the order of glycerol>alginate>lecithin>agar, while at 1% concentration, the order changed to glycerol>lecithin>alginate, whereas 1% agar behaved differently, increasing all rheological values. This study also showed that agar and alginate in addition to potato puree could be valuable and advantageous for further technological processes, such as 3D printing.