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21.
Dried blood spots for fatty acid profiling are increasing in popularity; however, variability in results between laboratories has not been characterized. Whole blood from two subjects (low and high n-3 polyunsaturated fatty acid [PUFA] status) was collected, 25 μL applied to butylated hydroxytoluene (BHT)-treated chromatography strips, dried in air, and shipped to five laboratories. Results were reported as “routine” (typical fatty acids for each laboratory) or “standardized” (a set of 19 fatty acids), and outliers and variability (%CV) were determined. Five and eight outliers of a possible 91 measures each were identified by routine and standardized reporting, respectively, including eicosapentaenoic acid (EPA, 20:5n-3) in the low n-3 PUFA sample and arachidonic acid in the high n-3 PUFA sample. By standardized reporting, no outliers were identified for EPA or docosahexaenoic acid (DHA, 22:6n-3), and %CV decreased from 8.6% to 6.0% and 9.1% to 6.6% for EPA and 10.5% to 7.2% and 10.5% to 6.6% for DHA in the low and high n-3 PUFA sample, respectively. In conclusion, fatty acid profiles yielded few outliers, and standardization of reporting reduced the variability between laboratories.  相似文献   
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In an effort to enforce the knowledge on mycotoxin occurrence and co-occurrence in dates and dried fruits, 228 samples purchased from Tunisian and Spanish markets were subjected to multi-mycotoxin liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis of 16 mycotoxins. At least one mycotoxin was detected in 160 samples (70%). The frequency of contaminated samples was 83%, 80%, 64%, 59% and 26% for dates, dried vine fruits, figs, apricots and plums, respectively but none of the analyzed samples contained detectable levels of fumonisins (FB1, FB2, FB3) or T-2 toxin (T2).The incidence and levels of mycotoxins varied in samples. The most prevalent mycotoxin was enniatin B (EnnB) (54%), followed by enniatinA1 (EnnA1) (36%); aflatoxins (AFs) (23%) and ochratoxin A (OTA) (22%). Thirteen samples contained AFs in levels that exceed the maximum limits established in EU legislation. The simultaneous contamination with 2–6 mycotoxins was observed in 51% of the analyzed samples. Lastly, intakes of the detected mycotoxins were calculated for average adult consumers and compared with the tolerable daily intakes (TDI). Data obtained were used to estimate the potential exposure levels.  相似文献   
24.
Egg white protein and soy protein were incorporated into a banana and cassava flour blend (75:25) to produce gluten-free pasta. The objectives of study were to investigate the effects of the different protein sources on the physico-chemical properties of gluten-free pasta. The levels of protein inclusion were 0%, 5%, 10% and 15% of composite flour (w/w) for each type of protein. Pasta made from 100% durum wheat semolina was used as controls. The protein fortification affected the total starch, resistant starch and protein content of gluten-free pasta compared to semolina pasta. No significant effects of soy/egg white protein addition were found in either insoluble or soluble dietary fibre content. Cooking properties of pasta (optimum cooking time, swelling index, water adsorption index and cooking loss) and texture properties (firmness and extensibility) were affected by the level of protein addition and the type of protein. Results showed the utilisation of 25% cassava flour and protein inclusion have a promising application in gluten-free pasta production.  相似文献   
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Extract from Salicornia europaea was added to durum wheat fresh pasta. Sensory properties, cooking quality, microbiological stability, content in bioactive compounds and antioxidant activity, before and after pasta digestion were studied. The extract was obtained by ultrasound-assisted extraction. From the technological point of view the extract did not affect pasta dough and the cooking parameters and sensory properties of the enriched samples were found similar to the control pasta. No antimicrobial effect was exerted by the extract. From the chemical point of view interesting findings were recorded for pasta before and after digestion. Specifically, data of bioaccessible fraction of digested sample showed a significantly higher amount of total phenols and flavonoid content (11.52 mg gallic acid g−1 and 0.55 mg quercetin g−1 respectively) than digested control pasta (9.54 mg gallic acid g−1 and 0.23 mg quercetin g−1 respectively). The antioxidant activity of enriched sample also increased compared to the control pasta (6.20 vs. 2.50 μmoles FeSO4 g−1).  相似文献   
27.
Experimental measurements were conducted of the minimum fluidization velocities and the entrainment (terminal) velocities for beds of dry, digested wastewater sludge particles. With the use of air, experiments were performed in an 80 mm i.d. glass column with carefully sieved, very narrow fractions of particles in a wide range of 0.65-5.3 mm. Physical examinations of the dried sludge particles revealed their irregular, mostly isometric shapes, their porous character, and their fibrous nature. New correlations, which cover the transitional flow region, have been developed to estimate the conditions of incipient fluidization and those of entrainment for such peculiar materials. Their explicit forms also enable the direct computation of the particle size corresponding to a chosen terminal velocity and the straightforward calculation of the terminal velocity of a given, irregularly shaped particle.  相似文献   
28.
应用静态称重技术测定了固体蜂蜜的吸附平衡含水率,获得了相应的吸附等温线,对其吸附规律进行了探讨,并根据目前在食品吸湿规律研究中常用的六种模型对不同温度条件下固体蜂蜜的吸湿试验进行了模拟比较,得出GAB模型为固体蜂蜜适用的吸湿模型,并确定了模型系数。  相似文献   
29.
This study investigates the sintering behavior of dried sewage sludge and the related sintering mechanisms, considering sintering temperature and sintering time. Experimental results indicate that the characteristics are primarily influenced by sintering temperature. When the sintering temperature is increased from 1020 to 1050 °C, the specimens’ compressive strength and bulk density increase significantly, while water absorption decreases obviously, indicating an improvement of densification due to sintering. However, the compressive strength cannot meet the requirement for traditional ceramic products due to the release of organic matters and the formation of big pores in the products. Phosphorus in sewage sludge initially takes reactions with the formation of calcium magnesium phosphate and aluminum phosphate during sintering, which are helpful for enhancing the compressive strength. So, some materials with high contents of Al could be used to enhance the compressive strength of products. Heavy metals are fixed primarily inside the sintered specimens, with the As, Pb, Cd, Cr, Ni, Cu, Zn concentrations in the leachate found to be in the range of China regulatory requirements. These results reveal the feasibility of recycling dried sewage sludge by sintering as a construction material.  相似文献   
30.
This study investigated lipid oxidation in spaghetti enriched in long chain n−3 polyunsaturated fatty acids (LC n−3 PUFA) by the addition to semolina of an integrator containing eicosapentaenoic acid and docosahexaenoic acid. Two oxidative parameters were evaluated: peroxide value (PV), to assess primary oxidation and oxidised fatty acids to quantify secondary oxidation products. Functional spaghetti had a shelf life comparable to control pasta. LC n−3 PUFA were not significantly implicated in the onset of oxidation in spaghetti stored under daylight and accelerated oxidation in a laboratory heater. Storage decidedly affected shelf life: PV in functional spaghetti increased from 7.1 to 43.4 meq O2/kg of fat under light exposure over 12 months, and from 7.1 to 16.2 meq O2/kg under accelerated ageing at 55 °C for 27 days, reproducing about 18 months at room temperature. Oxidised fatty acids increased in fortified spaghetti from 4.8 to 13.8 g/100 g of fat under light exposure over 12 months and from 4.8 to 7.8 g/100 g of fat at 55 °C in 27 days. The high sensitivity of spectrophotometric and chromatographic analytical methods permitted the evaluation of primary and secondary oxidative derivatives in small amounts of fat.  相似文献   
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