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51.
The aim of this work was to examine the effect of blanching or soaking in different acid solutions on the acrylamide content in potato crisps. Furthermore, the effects of a shorter frying time and a lower frying temperature combined with a postdrying were investigated. Soaking or blanching of potato slices in acidic solutions decreased the pH of potato juice and increased the extraction of amino acids and sugars. Potato crisps obtained after such pretreatments were characterized by lower acrylamide content. The most effective extraction of free amino acids and sugars as well as the largest decrease of acrylamide content (90%) in crisps was obtained when potato slices were soaked in acetic acid solution for 60 min at 20 degrees C. Shorter frying time followed by postdrying resulted in low-moisture potato crisps. Furthermore, the postdrying treatment gave a decreases in acrylamide content of approximately 70% when potato slices were fried at 185 degrees C and approximately 80% when potato slices were fried at 160 degrees C. Effective ways of decreasing acrylamide content in crisps production have been found. Crisps with low acrylamide content and good sensory quality can be obtained either by blanching in acetic acid as pretreatment or by a short frying followed by postdrying.  相似文献   
52.
ABSTRACT

Disease development in plants is strongly dependent on weather conditions, with temperature playing a particularly significant role by influencing latency period duration. Using two models describing the relationship between latency period and temperature, we performed simulations aimed at predicting changes in the latency period of leaf rust (Puccina recondita f. sp. tritici) on triticale in response to expected climate change. The simulations were based on meteorological data recorded in the period 1986–2005 at locations representing 16 provinces in Poland and based on values obtained after transformation of the observed data to reflect temperature changes under four scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) according to the giss_e2_r climate model. In all scenarios, the results for the two triticale cultivars studied, Witon (vulnerable to P. recondita) and Gniewko (less susceptible), showed a threat of faster development (shorter leaf rust latency period) on triticale triggered by climate change in south-east and south-central Poland than in other regions. The results also showed an increased probability of future regional diversification of leaf rust latency period duration on vulnerable triticale cultivars, opportunities for earlier start of leaf rust epidemics on triticale in Poland and an increase in ?nal disease severity in comparison with 1986–2005.  相似文献   
53.
(E)-1-(2,3,6-Trimethylphenyl)buta-1,3-diene (TPB) was identified as a potent odorant in acid hydrolysates of crude glycoconjugate fractions isolated from grapes and grape vine leaves. TPB was also identified in a Semillon wine, using gas chromatography/mass spectrometry, by co-injection with an authentic sample. TPB had an aroma detection threshold of 40 ng/L in a neutral white wine and the concentration of TPB in four out of five white wines analyzed ranged from 50 to 210 ng/L.  相似文献   
54.
The aim of this study was to evaluate the applicability of the Cryotech technique for the vitrification of domestic cat (Felis catus) oocytes, as a model for other feline species threatened with extinction. This technique, in which oocytes are stored in a minimal volume of medium, is already widely used in human assisted reproductive technology. In the first part of this study, a viability test (EtBr/FDA) was used to evaluate the toxicity of the vitrification media (solutions). After IVM, oocytes were placed in vitrification and warming solutions according to the manufacturer's procedure, with or without exposure to liquid nitrogen. The solutions and the vitrification procedure each caused a reduction in oocyte viability, with survival rates of 71.4% in oocytes exposed to the Cryotech media (without cooling in liquid nitrogen), and 62% in oocytes that were vitrified. In the second part of the experiment, parthenogenetic activation was used to evaluate the developmental potential of oocytes previously vitrified using the Cryotech method. After warming, the oocytes were activated using a combination of 0.7 µM ionomycin in TCM 199 medium (5 min) followed by 2 mM 6-DMAP in TCM 199 supplemented with 10% FBS (3 hr), then cultured and evaluated every 24 hr for parthenogenetic cleavage. In the experimental group, 23/50 (46%) cleaved embryos were obtained. Domestic cat oocytes, vitrified by the Cryotech method, are characterized by high survival rates. However, it is necessary to improve the technique to increase the developmental competence of embryos obtained from vitrified oocytes.  相似文献   
55.
The formation of furan upon sterilization of a lipid-containing starch gel was investigated in the presence of various antioxidants, namely, α-tocopherol, β-carotene, and ascorbic acid, with and without proteins. Results indicated that α-tocopherol did not significantly influence furan formation from oxidized lipids. β-Carotene, suggested previously to be a furan precursor itself, did influence the generation of furan in a concentration-dependent manner, although to a limited extent. Surprisingly, the presence of lipids seemed to limit the furan generation from β-carotene. Interestingly, the addition of ascorbic acid to the emulsions containing soybean or sunflower oils considerably enhanced the formation of furan from these oils. This was also the case when fresh oils were applied, shown previously to be nearly unable to generate furan. This observation can be explained by an intensified ascorbic acid degradation stimulated by the presence of lipids.  相似文献   
56.
The aim of the study was to analyze the factors creating consumer attributes of roasted beef steaks of various animals. Eight cuts from 30 carcasses (characterized by various types of animal, conformation and fat class, rib fat thickness, ossification score) were selected. Samples were prepared using the roasting method and consumers rated the tenderness, juiciness, flavor, overall acceptability (rated in a 100‐point scale), and satisfaction (rated from 2 to 5) for analyzed samples. No influence of type of animal, fat class, conformation class or ossification score on the results of consumer analysis was observed. For all analyzed factors, the influence of cut on consumer analysis was observed (the highest values of all consumer attributes were observed for tenderloin ‐ for juiciness significantly higher than for other cuts, for tenderness, flavor and MQ4 comparable only with rump (RMP231), while for overall acceptability and satisfaction – with both rump cuts). For rib fat thickness consumer attributes of roasted beef meat were not linear, but the influence was observed – the highest values of consumer attributes were observed for 13 mm rib fat thickness.  相似文献   
57.
Seasonal variability of Cu, Pb, and Zn concentrations in litter leachates and soil solutions was examined in an afforested zone surrounding a copper smelter in SW Poland. Litter leachates (with zero‐tension lysimeters) and soil solutions (with MacroRhizon suction‐cup samplers, installed at a depth of 25–30 cm) were collected monthly at three sites differing in contamination levels in the years 2009 and 2010 (total Cu: 2380, 439, and 200 mg kg–1, respectively). Concentrations of Cu in the litter leachate were correlated with dissolved organic C (DOC), whereas Zn and Pb were mainly related to leachate pH. Metal concentrations in the soil solution were weakly influenced by their total content in soils and the monthly fluctuations reached 300, 600, and 700% for Cu, Pb, and Zn, respectively. Metal concentrations in soil solutions (Cu 110–460 μg L–1; Zn 20–1190 μg L–1; Pb 0.5–36 μg L–1) were correlated with their contents in the litter leachates. Chemical speciation, using Visual Minteq 3.0, proved organically‐complexed forms even though the correlations between metal concentrations and soil solution pH and DOC were statistically insignificant. The flux of organically‐complexed metals from contaminated forest floors is believed to be a direct and crucial factor affecting the actual heavy metal concentrations and their forms in the soil solutions of the upper mineral soil horizons.  相似文献   
58.
Upon intravenous transplantation, hematopoietic stem cells (HSCs) can home to specialized niches, yet most HSCs fail to engraft unless recipients are subjected to toxic preconditioning. We provide evidence that, aside from immune barriers, donor HSC engraftment is restricted by occupancy of appropriate niches by host HSCs. Administration of ACK2, an antibody that blocks c-kit function, led to the transient removal of >98% of endogenous HSCs in immunodeficient mice. Subsequent transplantation of these mice with donor HSCs led to chimerism levels of up to 90%. Extrapolation of these methods to humans may enable mild but effective conditioning regimens for transplantation.  相似文献   
59.
Journal of Soils and Sediments - Industrialization and application of large amount of fertilizers together with animal wastes increased pollution of environment with antibiotics and heavy metals....  相似文献   
60.
In this study, different Polish cultivars of blue-berried honeysuckles (Lonicera caerulea L.), wild and bog bilberry, were analyzed for bioactive compounds. The chemical properties verified included composition of anthocyanins and other polyphenols, antioxidant activity, and profiles of antioxidants by HPLC postcolumn derivatization or TLC. The antioxidant activities of different blue-berried honeysuckle cultivars were similar to that of wild-growing bilberries (ranging from 170 to 417 μmol TE/g dm in ABTS and from 93 to 166 μmol TE/g dm in DPPH and Folin-Ciocalteu tests). The major anthocyanin in the blue-berried honeysuckle was cyanidin-3-glucoside, which constituted 84-92% of the total anthocyanins. The TLC and HPLC postcolumn antioxidant profiles indicated that anthocyanins are the major antioxidants in all berries studied. Wild berries and the cultivars of the blue-berried honeysuckles are also a similar source of such minerals as K, Mg, and Ca.  相似文献   
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