Infant formula fatty acid profile following microwave heating.

Microwave heating of foods may alter their content. Yet, parents commonly heat infant formula in the microwave oven. The study aimed at understanding whether microwave heating of formula changes its fatty acid (FA) composition. Portions of infant formula were prepared and divided in three parts: control (sampled twice: at the start and after 30 minutes), microwave (sampled twice: after reaching 37°C and 50°C), and water bath (sampled twice: after reaching 37°C and 50°C). In thus obtained samples, a total profile of 25 FA was assessed using gas chromatography-mass spectrometry. Overall, fourteen portions were prepared, which were sampled 84 times yielding 2075 individual total FA level measurements. Few differences were identified between the microwave, control, and water bath groups. Microwave warming to 37°C was associated with increases of C12 (median increased by +0.40%, p = 0.0063), C14 (+0.05%, p = 0.0091), and C4 content (+6.90%, p = 0.0131). Microwaving up to 50°C slightly decreased C16:1trans (-5.00%, p = 0.0463) and C18:2trans1 (-5.13%, p = 0.0231). A paired comparison of pooled control and microwaved samples revealed increases in C12 (+0.18%, p = 0.0490) as well as a loss of C18:2trans1 (also -5.13%, p = 0.0073) and C18:2trans3 (-5.56%, p = 0.0042) after microwave treatment. C18:2trans1 (-2.63%, p = 0.0132) and C18:3trans1 (-2.26%, p = 0.0434) were lower in microwaved samples compared with the water bath. A slightly lower C18:2 content was found in the water bath samples than in the control groups (-0.11%, p = 0.0430). None of these differences would remain significant after a correction for multiple comparisons. Microwave heating of infant formula to 37°C or 50°C might marginally alter its total FA profile. Further studies are required to determine whether it alters the rate of free radical formation

The Lipid-Soluble Bioactive Substances of <i>Fagopyrum esculentum</i> Varieties under Different Tillage and Nitrogen Fertilisation

Yield and grain composition play an important role in food production. The aim of this study was to determine the content of phytosterols, squalene, and tocopherols in four varieties of common buckwheat grains: Kora, Panda, Smuga, and Korona depending on the tillage and nitrogen doses employed. The grains were cultivated at the Experimental Station of the State Research Institute of Soil Science and Plant Cultivation in Osiny, Poland, with plow tillage, without plow tillage cultivation, and with nitrogen fertilizers (0, 50, and 100 kg N2 ha−1). Gas chromatography with a mass spectrometer was used to assess all the parameters studied. The cultivation methods did not affect the levels of phytosterols, tocopherols, and squalene, but the highest levels of phytosterols were seen in the Kora variety with 50 kg N2 ha−1 (ranging from 1198 μg to 1800 μg·g−1 of sample weight); therefore, the variety was the best source of phytosterols investigated

Heterogeneous effect of aging temperature on the fatigue life of additively manufactured thin-walled 18Ni300 maraging steel tubular specimen

Optimizing the geometry for material savings, or heat transfer, can yield thin-walled additively manufactured parts. A wall thickness of only a few hatching spaces can be fabricated using laser powder bed fusion (LPBF). However, the unmachined surface quality and subsurface defects in the low-thickness wall put the load-bearing capacity of the manufactured part under scrutiny. This study aimed to determine the fatigue and quasi-static strengths of nominally 0.5-mm thick tubular specimens of LPBF 18Ni300 maraging steel with respect to the aging temperature (AT). The experimental tests were conducted on six batches of unmachined specimens: non-aged and age-hardened for 6 h at different temperatures, i.e., 450, 470, 490, 530, and 585 °C. The void distribution and specimen surface were characterized using X-ray micro-computed tomography. The heterogeneous effect of AT on fatigue life was recognized by a novel application of the Gaussian process for regression. The mechanical properties of a 0.5-mm thick tubular specimen were equal to or higher than those of a full cross-section specimen. Furthermore, the optimal AT to obtain the highest fatigue strength was 520 °C for low-cycle fatigue, decreasing to 480 °C for high-cycle fatigue

Severe Genotype, Pancreatic Insufficiency and Low Dose of Pancreatic Enzymes Associate with Abnormal Serum Sterol Profile in Cystic Fibrosis

Background: Several factors could lead to lipid disturbances observed in cystic fibrosis (CF). This study aimed to assess sterol homeostasis in CF and define potential exogenous and endogenous determinants of lipid dysregulation. Methods: The study involved 55 CF patients and 45 healthy subjects (HS). Sterol concentrations (μg/dL) were measured by gas chromatography/mass spectrometry. CF was characterised by lung function, pancreatic status, liver disease and diabetes coexistence, Pseudomonas aeruginosa colonisation and BMI. CFTR genotypes were classified as severe or other. Results: Campesterol and β-sitosterol concentrations were lower (p = 0.0028 and p p = 0.0016) in CF patients than in HS. Campesterol and β-sitosterol concentrations were lower in patients with a severe CFTR genotype, pancreatic insufficiency and lower pancreatic enzyme dose (lipase units/gram of fat). In multiple regression analyses, β-sitosterol and campesterol concentrations were predicted by genotype and pancreatic insufficiency, whereas cholesterol and its fractions were predicted by phytosterol concentrations, age, dose of pancreatic enzymes, nutritional status and genotype. Conclusions: Independent determinants of lipid status suggest that malabsorption and pancreatic enzyme supplementation play a significant role in sterol abnormalities. The measurement of campesterol and β-sitosterol concentrations in CF patients may serve for the assessment of the effectiveness of pancreatic enzyme replacement therapy and/or compliance, but further research is required