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901.
Rheological properties such as Casson viscosity and yield value strongly affect costs and efficiency of the chocolate making process. The addition of a proper amount of lecithin to the blend of chocolate ingredients results in a decrease of both the aforementioned parameters. However, overdosing of lecithin leads to worse sensory attributes and flow properties of the chocolate mass. Our studies on rheological properties of isomalt-containing dark chocolate masses and sucrose-containing milk chocolate masses revealed that the critical lecithin concentration was 0.9 g/100 g; and the Casson yield value of both the types of chocolate blends was enhanced above this content. The same phenomenon, i.e. chocolate thickening, was observed at lecithin concentrations of 0.4 g/100 g and 0.6 g/100 g for milk chocolate masses sweetened with isomalt, and for dark chocolate masses sweetened with sucrose, respectively.  相似文献   
902.
Recently, agricultural by‐products, for instance, corn husks, oat husks, or cocoa shells, have gained attention as a source of cellulose fibers and fillers because they can save the land and other natural resources required to grow fiber crops. It has to be noted, however, that textile processing, for example, shearing, is also a source of waste fibers. Our study focuses on utilization of waste cotton fibers, amassed during shearing of textiles, as a filler for polylactide (PLA). PLA composites with 10–30 wt% of waste cotton fibers were prepared and their thermal and mechanical properties were studied. The composite with 30 wt% of fibers exhibited markedly higher storage and loss moduli as compared with neat PLA; at 25°C the storage moduli increased by 53% whereas the loss modulus increased by 76%. In addition, the yield strength was slightly improved, by 11% at 25°C. Although the composites were thermally less stable than neat PLA, their 5% weight loss temperature remained high, about 300°C. POLYM. COMPOS., 35:747–751, 2014. © 2013 Society of Plastics Engineers  相似文献   
903.
This study was undertaken to determine the effects of two commercially available brown onion varieties, ‘Cavalier’ and ‘Destiny’, supplemented at two different levels, on blood lipid and oxidative status using the pig as a model. Twenty‐five female cross‐bred pigs were allocated to one of five dietary treatments that consisted of a high‐fat control diet with no onion added, a low onion dose of 10 g onion MJ?1 DE and a high dose of 25 g onion MJ?1 DE for each variety of onion. Supplementation with ‘Destiny’ onion resulted in a 21% (p < 0.05) reduction in the averaged fasted and postprandial plasma triacylglyceride (TG) measurements taken over the six‐week period in comparison with the control pigs. The average fasting and postprandial plasma cholesterol concentrations were significantly reduced by 5.5 and 12.4% in pigs that consumed the low and high dose of ‘Destiny’ onion, respectively (p < 0.010), while ‘Cavalier’ was only effective at lowering cholesterol levels by 10% at the lower dose of supplementation. Inhibition in the rate of serum lipoprotein oxidation, measured as lag time, was increased by 23% (p < 0.05) in plasma obtained from pigs that consumed ‘Cavalier’ compared with the control and ‘Destiny’ onion diets. These data indicate that onion consumption level may provide a dietary means of manipulating some of the risk indices associated with coronary heart disease, but the responses varied with type and dose of onion. Copyright © 2004 Society of Chemical Industry  相似文献   
904.
The goal of this research was to evaluate the application of Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method for the determination of organochlorine, organophosphate, and carbamate pesticides in fatty animal matrices such as liver of chicken obtained from National Research Institute of Animal Production in Balice (Poland). Pesticides extraction effectiveness was evaluated at two different spiking levels (0.010 and 0.020 mg kg?1) and efficiency of the dispersive solid-phase extraction (d-SPE) clean-up step was evaluated by comparison adding different d-SPE sorbent combinations (PSA?+?GCB, PSA?+?C18, PSA?+?SAX, and PSA?+?NH2). The analysis of pesticide residues was performed by gas chromatography ion trap mass spectrometry (GC/IT-MS). The linear relation was observed from 0 to 400 ng mL?1 and the determination coefficient R 2?>?0.997 in all instances for all target analytes. Better recoveries were obtained in samples at 0.020 mg kg?1 spiking level. The recoveries were in the range 70–120 %, with relative standard deviation (RSD) values lower than 15 % at 0.020 mg kg?1 spiking level for most pesticides. Similar recovery ratios were obtained with the four different combinations of sorbents tested in the clean-up step, with better precision when the (PSA?+?SAX) combination was tested. Limits of detection (LODs) ranged from 0.001 to 0.005 mg kg?1 and limits of quantification (LOQs) ranged from 0.003 to 0.015 mg kg?1. The proposed method was successfully applied analyzing pesticide residues in real chicken liver samples; detectable pesticide residues were observed, but in all of the cases, the contamination level was lower than the default maximum residue levels (MRLs) set by European Union (EU), Regulation (EC) N 396/2005.  相似文献   
905.
The objective of this study was to determine the health benefits of extra‐virgin and refined olive oils, which are high in mono‐unsaturated fatty acids (MUFAs) and polyphenolic compounds using the pig as a model. Thirty‐two cross‐bred pigs were individually penned, allocated to one of four dietary treatments and fed ad libitum for 28 days. Two of the experimental diets consisted of a basal diet containing 12% tallow and either 7% sunflower oil (TSO) or 7% extra‐virgin olive oil (TEVO) on a w/w basis. The remaining diets contained 19% extra‐virgin olive oil (EVO) or 19% of refined olive oil (RO). On days 7, 14 and 28 fasted and 3‐h post‐prandial blood samples were taken. Body composition was measured at the beginning and end of the study using dual energy X‐ray absorptiometry. Daily gain, feed intake and lean and fat deposition were not significantly different between the treatments. However, the daily increase in bone mineral density was higher in pigs fed diets containing olive oil (1.23 vs 2.54, 6.28, 5.20 mg cm?2 per day for TSO, TEVO, EVO and RO, respectively, P = 0.050). Both fasting and non‐fasting plasma triglycerides were lower (P = 0.003) in pigs fed MUFA‐rich diets, while the cholesterol profile was not significantly different between the treatments. The results from in vitro copper‐induced lipid peroxidation, expressed in terms of conjugated dienes, showed that low density lipoprotein (LDL) particles in postprandial serum from pigs fed olive oil were moderately more resistant to oxidative modification. In conclusion, these data demonstrate that both extra‐virgin and refined olive oils attenuate postprandial hypertriglyceridaemia, moderately affect oxidation susceptibility and increase bone mineral density in growing pigs. Copyright © 2006 Society of Chemical Industry  相似文献   
906.
Abstract

The growing concerns over product quality have increased demand for high quality dried food products and encouraged researchers to explore and producers of such products to implement novel microwave (MW)-assisted drying methods. This paper presents a critical review of the key principles and drawbacks of MW-assisted drying as well as needs for future research. In this article, recent research into application of microwaves as an alternative heat source, applications and progress in hybrid MW-assisted drying that rely on various drying media and combined two or three stages of MW-assisted drying for the preservation of food products is reviewed critically. The effect of different MW-assisted drying methods, conditions and initial pretreatments on the thermophysical properties, color, nutritional value and rehydration potential of dried food products is discussed in detail along with the discussion on how the material properties evolve and change in structure, color, and composition during MW-assisted drying and recent attempts at mathematical modeling of these changes made for different fruits and vegetables. It should be noted that most of the published results were obtained in laboratory-scale dryers. Pilot-scale testing is needed to bridge the gap between laboratory research and industrial applications to fulfill the potential for novel hybrid and combined MW-assisted drying methods and to expand their role in food processing.  相似文献   
907.
908.
ABSTRACT:  Since lupin has been introduced as a food ingredient on the market there are more and more reports concerning its allergenic properties. However, only few narrow-leafed lupin proteins have yet been characterized as specific IgE-binding molecules and identified. The aim of the study has been to find and identify the main narrow-leafed lupin globulins that bind to specific IgEs from the sera of lupin-allergic people. Isolated lupin globulins were subjected to immunoblotting with the sera from people who suffered from lupin allergy. Incubation with α-methyl-D-galactopyranoside was performed to eliminate possible binding of unspecific human IgEs. The proteins binding specific IgEs from lupin-allergic patients' sera were identified by means of mass spectrometry. Western blot analysis revealed 2 signals corresponding to lupin globulins that bound to specific IgEs from the sera of people allergic to lupin. The globulins were identified as conglutin-γ and its smaller subunit. The results suggested that individuals that displayed lupin allergy symptoms reacted to conglutin-γ.
Practical Application: The results of the study can contribute to identification of yet undetected allergens of narrow-leafed lupin. This, in turn, can make lupin-fortified products safer for the consumers.  相似文献   
909.
Chronic kidney disease (CKD) is a global health issue, affecting more than 10% of the worldwide population. The current approach for formal diagnosis and prognostication of CKD typically relies on non-invasive serum and urine biomarkers such as serum creatinine and albuminuria. However, histological evidence of tubulointerstitial fibrosis is the ‘gold standard’ marker of the likelihood of disease progression. The development of novel biomedical technologies to evaluate exfoliated kidney cells from urine for non-invasive diagnosis and prognostication of CKD presents opportunities to avoid kidney biopsy for the purpose of prognostication. Efforts to apply these technologies more widely in clinical practice are encouraged, given their potential as a cost-effective approach, and no risk of post-biopsy complications such as bleeding, pain and hospitalization. The identification of biomarkers in exfoliated kidney cells from urine via western blotting, enzyme-linked immunosorbent assay (ELISA), immunofluorescence techniques, measurement of cell and protein-specific messenger ribonucleic acid (mRNA)/micro-RNA and other techniques have been reported. Recent innovations such as multispectral autofluorescence imaging and single-cell RNA sequencing (scRNA-seq) have brought additional dimensions to the clinical application of exfoliated kidney cells from urine. In this review, we discuss the current evidence regarding the utility of exfoliated proximal tubule cells (PTC), podocytes, mesangial cells, extracellular vesicles and stem/progenitor cells as surrogate markers for the early diagnosis and prognostication of CKD. Future directions for development within this research area are also identified.  相似文献   
910.
The aim of the study was to present the fingerprint of different Lepidium peruvianum tuber extracts showing glucosinolates-containing substances possibly playing an important role in preventinting dementia and other memory disorders. Different phenotypes of Lepidium peruvianum (Brassicaceae) tubers were analysed for their glucosinolate profile using a liquid chromatograph coupled with mass spectrometer (HPLC-ESI-QTOF-MS/MS platform). Qualitative analysis in 50% ethanolic extracts confirmed the presence of ten compounds: aliphatic, indolyl, and aromatic glucosinolates, with glucotropaeolin being the leading one, detected at levels between 0–1.57% depending on phenotype, size, processing, and collection site. The PCA analysis showed important variations in glucosinolate content between the samples and different ratios of the detected compounds. Applied in vitro activity tests confirmed inhibitory properties of extracts and single glucosinolates against acetylcholinesterase (AChE) (15.3–28.9% for the extracts and 55.95–57.60% for individual compounds) and butyrylcholinesterase (BuChE) (71.3–77.2% for the extracts and 36.2–39.9% for individual compounds). The molecular basis for the activity of glucosinolates was explained through molecular docking studies showing that the tested metabolites interacted with tryptophan and histidine residues of the enzymes, most likely blocking their active catalytic side. Based on the obtained results and described mechanism of action, it could be concluded that glucosinolates exhibit inhibitory properties against two cholinesterases present in the synaptic cleft, which indicates that selected phenotypes of L. peruvianum tubers cultivated under well-defined environmental and ecological conditions may present a valuable plant material to be considered for the development of therapeutic products with memory-stimulating properties.  相似文献   
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