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1.
Ida-Marie Andersson Björn Bergenståhl Marcela Alexander Marie Paulsson Maria Glantz 《International Journal of Food Science & Technology》2021,56(1):480-492
During whey powder production, the feed is subjected to several heat treatments which can cause lactosylation of proteins. In this study, lactosylation of whey proteins was evaluated in spray-dried powders before and after storage by varying the native protein fraction as well as the serum protein/lactose ratio in the powders. The lactosylation of native α-lactalbumin and β-lactoglobulin in the powders before storage was not affected to a large extent by the protein denaturation or if the feed had been heat treated in a high or low lactose environment. After storage (relative humidity of 23.5%, 30 °C, 25 days), the kinetic of lactosylation tended to increase with increasing native protein fraction and bulk protein content in the powders. An explanation could be that proteins dissolved in the lactose glassy structure might have a lower reactivity, while proteins present in the protein glassy structure with dissolved lactose may display higher lactosylation reactivity. 相似文献
2.
Roselle Barretto Rania Marie Buenavista Jared Lou Rivera Shuyu Wang P.V. Vara Prasad Kaliramesh Siliveru 《International Journal of Food Science & Technology》2021,56(7):3125-3137
The demand for food production has been constantly increasing due to rising population. In developed countries, for example, the emergence of regional production of old grains that are rarely utilized, along with the production of commonly consumed grains, has gained importance in recent years. These grains, known collectively as ancient or heirloom grains, have offered both farmers and consumers novel ways of cultivation and products with interesting taste, characteristics and nutritional value. Among the 30 000 plant species known, only five cereals currently provide more than 50% of the world's energy intake – bread wheat (Triticum aestivum), rice (Oryza sativa), sorghum (Sorghum bicolor), millets (Panicum sp.) and maize (Zea mays). The excessive utilization of these selected species has a great potential to cause genetic losses and difficulty in bridging future agricultural demands. Teff (Eragrostis tef), an ancient grain extensively cultivated in countries like Eritrea and Ethiopia, provides promising alternatives for new food uses since its nutritional value is significantly higher than most others cereal grains. The absence of gluten allows flexibility in food utilization since it can be directly substituted to gluten-containing products. The grain also offers an excellent balance of essential amino acids and minerals, which can fulfil the recommended daily intake and eliminates the need for fortification and enrichment. This review provides a general overview of the physical properties and nutritional composition of teff grains related to processing and applications in the food and feed industries. The current status of teff utilization, as well as the challenges in production and commercialization, and future opportunities is presented and discussed. 相似文献
3.
Lingfeng Zhou Zhipeng Zeng Michael P. Brady Donovan N. Leonard Harry M. Meyer Yukinori Yamamoto Wenyuan Li Greg Collins Xingbo Liu 《International Journal of Hydrogen Energy》2021,46(41):21619-21633
The chromium (Cr) evaporation behavior of several different types of iron (Fe)-based AFA alloys and benchmark Cr2O3-forming Fe-based 310 and Ni-based 625 alloys was investigated for 500 h exposures at 800 °C to 900 °C in air with 10% H2O. The Cr evaporation rates from alumina-forming austenitic (AFA) alloys were ~5 to 35 times lower than that of the Cr2O3-forming alloys depending on alloy and temperature. The Cr evaporation behavior was correlated with extensive characterization of the chemistry and microstructure of the oxide scales, which also revealed a degree of quartz tube Si contamination during the test. Long-term oxidation kinetics were also assessed at 800 to 1000 °C for up to 10,000 h in air with 10% H2O to provide further guidance for SOFC BOP component alloy selection. 相似文献
4.
Anna Enrico Wenjing Zhang Marie Lund Traulsen Elena Marzia Sala Paola Costamagna Peter Holtappels 《Journal of the European Ceramic Society》2018,38(7):2677-2686
Water-based sol-gel electrospinning is employed to manufacture perovskite oxide La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) nanofiber cathodes for intermediate-temperature solid oxide fuel cells. LSCF fibrous scaffolds are synthesized through electrospinning of a sol-gel solution employing water as the only solvent. Morphological characterizations demonstrate that the LSCF fibers have highly crystalline structure with uniform elemental distribution. After heat treatment, the average fiber diameter is 250 nm and the porosity of the nanofiber tissue is 37.5 %. The heat treated LSCF nanofibers are applied directly onto a Ce0.9Gd0.1O1.95 (CGO) electrolyte disk to form a symmetrical cell. Electrochemical characterization is carried out through electrochemical impedance spectroscopy (EIS) in the temperature range 550?°C–950?°C, and reproducibility of the electrochemical performance for a series of cells is demonstrated. At 650?°C, the average measured polarization resistance Rp is 1.0 Ω cm2. Measured performance decay is 1 % during the first 33?h of operation at 750?°C, followed by an additional 0.7 % over the subsequent 70?h. 相似文献
5.
Effects of breed and age at slaughter on degradation of muscle lipids during processing of dry‐cured hams
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Linda Storrustløkken Hanne Marie Devle Lars Erik Gangsei Carl Fredrik Naess‐Andresen Bjørg Egelandsdal Ole Alvseike Dag Ekeberg 《International Journal of Food Science & Technology》2015,50(8):1933-1943
Hams from Landrace, Duroc and Hampshire pigs slaughtered at ages 6, 7.5 and 9 months were processed to generate Norwegian Parma‐style hams. Lipid contents and the compositions of fatty acid classes (ΣSFA, ΣMUFA, ΣPUFA) within neutral lipids, phospholipids and free fatty acids were determined. Small differences in lipid degradation and composition of the classes were revealed. However, significant sensory differences related to lipids were observed. Breed was more important than age. Dry‐cured Hampshire hams gave a more intense mature odour that may be associated with higher overall lipid degradation. Unexpectedly, these hams also demonstrated high juiciness and tenderness, which could be related to the melting characteristics of the fat. Dry‐cured Duroc hams showed a higher susceptibility towards rancidity, presumably associated with preferential oxidation of n‐6 fatty acids relative to C18:1 n‐9. Dry‐cured Landrace hams showed the lowest juiciness and tenderness, likely due to their lower fat content (marbling). 相似文献
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S H Yoon J H Collins D Musale S Sundararajan S P Tsai G A Hallsby J F Kong J Koppes P Cachia 《Water science and technology》2005,51(6-7):151-157
A newly developed membrane performance enhancer (MPE) was used to prevent membrane fouling in a membrane bioreactor (MBR) process. It transpired that 1,000 mg/l of MPE reduced polysaccharide levels from 41 mg/I to 21 mg/I on average under the experimental condition. Repeated experiments also confirmed that 50-1,000 mg/l of MPE could reduce membrane fouling significantly and increase the intervals between membrane cleanings. Depending on MPE dosages and experimental conditions, trans-membrane pressure (TMP) increase was suppressed for 20-30 days, while baseline TMP surged within a few days. In addition, MPE allowed MBR operation even at 50,000 mg/l of total solid and reduced permeate COD. However, no evidence of toxicity for sludge was found from respiratory works. 相似文献
10.
This article argues that an iconic event in the history of helping research--the story of the 38 witnesses who remained inactive during the murder of Kitty Genovese--is not supported by the available evidence. Using archive material, the authors show that there is no evidence for the presence of 38 witnesses, or that witnesses observed the murder, or that witnesses remained inactive. Drawing a distinction between the robust bystander research tradition and the story of the 38 witnesses, the authors explore the consequences of the story for the discipline of psychology. They argue that the story itself plays a key role in psychology textbooks. They also suggest that the story marks a new way of conceptualizing the dangers of immersion in social groups. Finally, they suggest that the story itself has become a modern parable, the telling of which has served to limit the scope of inquiry into emergency helping. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献