The objective of this study was to determine the possibility of using Mixolab® to predict the cookie baking quality of different wheat flours. Mixolab data was also compared with various flour quality characteristics. There were significant correlations (P < 0.001) between Mixolab stability and some of the flour quality characteristics (protein and wet gluten contents, Zeleny sedimentation value). Alveoconsistograph T value was negatively correlated with Mixolab C3, C4 and C5 values. The cookie diameter gave highly significant correlations with protein content, Zeleny sedimentation value and damaged starch content. Mixolab C3 and C4 values were highly correlated (P < 0.001) with both cookie diameter and spread ratio. A significant correlation coefficient (r = 0.556) was determined between the cookie diameter and C1–C2 value which is an indication of protein quality. The dependence of cookie diameter and spread ratio on Mixolab C3 value, damaged starch content and Zeleny sedimentation value were analyzed with multiple regression analysis and high multiple correlation coefficients were found between these parameters (r = 0.948 and 0.861, respectively). 相似文献
Animal feeds and meat mixtures were analysed using the bioMerieux FoodExpert-ID® system. The system utilises a reverse dot technique on a DNA microarray to allow the identification of over 30 species of fish, birds and mammals. DNA is amplified by PCR (polymerase chain reaction) then hybridised to the microarray chip. Using this technique, turkey and chicken were correctly identified in 100% of feed samples that contained these species above a level of 0.1%. Pig, lamb and cow could not be reliably detected below a level of 1% in feed samples. For meat mixtures, a level of 0.2% pork or chicken could be correctly identified when mixed with 50% beef or pork, respectively. When a baked or canned meat mixture was investigated, a level of 5% pork, beef or chicken could be correctly identified, following either process. The bioMerieux FoodExpert-ID® system can therefore be used as a general screen to identify likely species present in a sample, the level of which can be confirmed using other methods. 相似文献
The objective of this study was to determine the possibility of using Mixolab® to predict the cake baking quality of different wheat flours. Mixolab® data were also compared with various flour quality characteristics. The correlations between Alveoconsistograph data and the cake quality characteristics were not significant. Therefore, Alveoconsistograph test does not seem to be useful to predict the cake quality of the flour samples. Mixolab® characteristics C2, C3, C4 and C5 were found to be significantly correlated with volume index while C5 was correlated with hardness of cakes. The parameters C2 to C5 represent the end point of the corresponding mixing stages. The flour samples which gave higher cake hardness values had higher C5 values and the samples with lower cake volumes had higher C2, C3, C4 and C5 values. It seems to be possible to estimate the texture and volume of cakes by these values. Therefore, Mixolab® seems to be a useful tool to predict the cake making quality of flour samples. 相似文献
Sioma® is a variety of red palm oil produced in Ecuador; it is mainly unsaturated, has no flavor, odor, nor cholesterol, and it is GMO-free and free of trans fatty acids. The main objectives of this study were: (a) to study changes in fatty acids, color coordinates, total carotenoids and carotenoid composition during deep-frying simulations; (b) to develop a mathematical model that allows quantification of total carotenoids (antioxidant compounds) using routine color measurements. Two different deep-frying temperatures were assayed 180 and 240 °C. The main fatty acids and carotenoids found in this oil were: (a) oleic, palmitic, and linoleic acids, and (b) α-, β-, and δ-carotenes. During these deep-frying simulations, Sioma® oil became lighter and more yellowish (L* and b* values increased) and more greenish (a* values decreased); these changes were more evident for higher temperatures. At 180 °C, total carotenoids decreased linearly, from almost 500 mg L?1, at a rate of 5 mg /kg1 min?1; however, at 240 °C the degradation of carotenoids was almost complete after 40 min. Finally, the mathematical models developed using multiple linear regressions allowed an easy and fast quantification of total carotenoids using color measurements. 相似文献
Fresh ginseng was irradiated with 60Co-γ or an electron beam at the dose of 2 and 4 kGy and stored at 2 °C. The quality of ginseng was evaluated after 60 and 120 days. Results suggest that when the storage time was 120 days, 2 kGy EI-treated ginseng had the lowest decay rate. During the 2 storage periods, the amounts of most of 9 ginsenosides decreased with an increase in the irradiation dose. The total saponin content of both 60Co-γ-irradiated and EI-treated samples decreased with an increase in the irradiation dose. Significant (P <?0.05) upregulation of total polysaccharide content was observed in the 4 kGy EI samples after storage. Samples irradiated at 2 or 4 kGy by electron beam irradiation had the highest concentration of total saponin and ginseng polysaccharides, respectively. Levels of most of 17 amino acids decreased with the increasing irradiation dose. Exposure to irradiation doses up to 4 kGy affected the amino acid content of fresh ginseng. Ginseng irradiated at 4 kGy by 60Co-γ irradiation and stored for 120 days had a significantly higher activity of superoxide dismutase (P <?0.05). A significant difference was observed in the total concentration of nucleosides and nucleobases between irradiated and un-irradiated ginseng samples (P <?0.05). These data suggest that the combination of a lower irradiation dose and low temperature is an optimal condition for extending the shelf-life of fresh ginseng without detriment to its ingredients. 相似文献
Identification of crops present in food and/or feed matrices represents an important step in the screening strategies targeting genetically modified organisms (GMO). Soybean, maize, oilseed rape, rice, cotton, sugar beet and potato are to date the most important sources of genetically modified materials imported in the European Union (EU). In order to allow detection of their presence in an integrated screening approach, a set of SYBR®Green real-time polymerase chain reaction (qPCR) methods has been developed which can be used under the same assay conditions and at similar efficiency for each of the abovementioned crops. Each qPCR method is shown to meet the performance criteria (i.e. specificity, limit of detection and PCR efficiency) set by the European Network of GMO Laboratories (ENGL). When combined with the equivalent qPCR methods targeting GMO elements, these crop-specific SYBR®Green qPCR methods can aid the development of an efficient tool for determining GMO presence in food and/or feed products. 相似文献
Extracellular and intracellular α-galactosidases were produced by yeast Debaryomyces hansenii UFV-1 grown on different media with several carbon sources. D. hansenii grown in YP-medium (1% yeast extract and 2% peptone) presented maximum cell mass (8.45 mg/mL) after 36 h of cultivation,
with lactose as carbon source, followed by sucrose, glucose, raffinose, and galactose. Higher extracellular and intracellular
α-galactosidases activities were observed at 48 h of D. hansenii cultivation in YPmedium containing galactose (0.97 and 5.27 U/mL) and lactose (1.28 and 4.88 U/mL), supporting the evidence
for the model of induction for the yeast GAL/MEL regulon, such as described in Sacharomyces cereviseae. 相似文献
Growth stress is important to achieve upright growth and avoid exterior influence on living trees. However, many problems are also triggered by the release of growth stress during wood processing, such as end split of log, distortion of board and inaccurate sawing. In order to evaluate the possibility of these problems to occur in poplar clone 107, a new breeding poplar clone in China, surface longitudinal growth strain (SLGS) and internal longitudinal growth strain (ILGS) both of straight and inclined trees were measured for depicting distributing patterns of growth strain both in peripheral and radial directions. Besides that, according to one-way ANOVA analysis, individual tree and peripheral position have a significant effect on SLGS in inclined trees, whereas such effect is insignificant in straight trees. Fiber morphology and shrinkage of wood sample beneath the SLGS testing positions were determined to illustrate the relationships between these properties with SLGS. The results suggested that growth stress is a poor indicator of fiber morphology and wood shrinkage properties for straight trees but a good one for inclined trees. Both the positive SLGS and ILGS are unexpectedly found at the opposite wood side of inclined trees. It is speculated that when the reorientation of inclined trees is insufficiently supported by exerting tensile stress at tension wood side, compressive stress will be formed at the opposite wood side as a complement. 相似文献
This study was designed to characterize a β-glucosidase from Oenococcus oeni 31MBR, a strain widely used in Chinese winemaking. An intracellular β-glucosidase (EC 3.2.1.21) was partially purified using a combination of ammonium sulfate precipitation and chromatographic methods. A single band was obtained in SDS-PAGE electrophoresis, indicating that the enzyme was highly purified and had an estimated molecular mass of 38.9 kDa. The enzyme exhibited highest activity at pH 4.5–5.0. The optimum temperature was 45 °C. Ethanol promoted the activity of this enzyme up to three times. Among the several metal ions assayed, only Mn2+ exhibited a partial promotion effect. The Km and Vmax values for p-nitrophenyl-β-d-glucopyranoside were 1.05 mmol/L and 0.957 nmol/min, respectively. Up to now, this study contains the first characterization of a native β-glucosidase purified from crude extracts of O. oeni 31MBR. 相似文献
This paper reports the production of a novel magnetic nanocomposite based on multi-walled carbon nanotubes (MWCNTs) decorated with magnetic core–shell Fe3O4@SiO2 nanoparticles which were used to fabricate a modified carbon paste electrode (Fe3O4@SiO2/MWCNT-CPE). The Fe3O4@SiO2/MWCNT-CPE was investigated for the simultaneous determination of sunset yellow (SY) and tartrazine (TT) in 0.1 mol/L phosphate buffer solution (pH 6.0) using square wave voltammetry (SWV). The synthesized nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy. The proposed electrode exhibits linear ranges of 0.5–100 μmol/L SY and TT with detection limits of 0.05 and 0.04 μmol/L for SY and TT, respectively. The novel proposed voltammetric method was successfully applied in the simultaneous determination of SY and TT in food products, with results similar to those obtained using a HPLC method at 95 % confidence level.
Graphical Abstract A magnetic nanocomposite based on MWCNTs decorated with core–shell Fe3O4@SiO2 was prepared and showed good ability to distinguish the response of SY and TT
In this study, different solvent extracts of skullcap (Scutellaria baicalensis) were assayed for their total phenol content (TPC), antioxidant activity [determined as DPPH radical scavenging activity,
superoxide dismutase (SOD)-like activity, oxygen radical absorbance capacity (ORAC) assay, and comet assay], and α-glucosidaseinhibitory
activity. The TPC of skullcap ranged from 9.06 mg/g gallic acid equivalents (GAE) for acetone extract (AE) to 91.8 mg/g GAE
for methanol extract (ME). AE, which had a low TPC, exhibited the highest DPPH radical scavenging activity and SOD-like activity.
TPC positively correlated with the ORAC assay (r=0.96, p<0.001). All skullcap extracts significantly reduced the hydrogen peroxide-induced DNA damage in human leukocytes. ME with
a high TPC and ORAC value showed the highest α-glucosidase inhibition. The difference in the biological activities of the
extracts may be due to the differences in their chemical structure or polarity. Therefore, the results obtained indicate that
might be a potential source of compounds with health-protective effects. ME, in particular, might be a prospective therapeutic
agent for diabetes. 相似文献
The hydrolysis of -oryzanol, a cholesterol-lowering and antioxidative mixture of steryl ferulates (mainly 24-methylenecycloartanyl ferulate 1, cycloartenyl ferulate 2, campesteryl ferulate 3, and-sitosteryl ferulate 4) occurring in rice, by commercially available enzyme preparations was investigated. Lipase preparations from different sources did not accept-oryzanol as substrate. Cholesterol esterases, however, catalyzed a sterol-specific reaction, i.e.,-sitosterol and campesterol were liberated from 3 and 4, whereas 1 and 2 remained unhydrolyzed. The same specificity profile was observed for hydrolysis of-oryzanol in artificial pancreatic juice and in reactions catalyzed by pancreatic acetone powders. The data indicate that pancreatic cholesterol esterase is involved in the hydrolysis of-oryzanol in vivo. They also provide a perspective for tailoring the composition of steryl ferulate mixtures on a large scale. 相似文献
Oilseed rape (Brassica napus L.) is an important agronomic crop used for oil, food and animal feed. Glyphosate resistant B. napus is tolerant to the herbicide glyphosate and has been widely adopted due to higher economic returns. However, a concern for
growing transgenic B. napus is the potential escape of cp4 epsps transgene via cross fertilization with wild and/or weedy species including Brassica juncea, especially in China, where B. juncea is prevalent. We assessed transgene inheritance and quantification upon wild B. juncea × transgenic B. napus outcrossing from three backcross (BC) generations and their progenies using real-time PCR. Under in vitro conditions, a stable
inheritance and similar cp4 epsps copy number between different generations (BC2, BC3 and BC4) and their progenies were observed. A marginally higher copy
number was observed when B. juncea was used as the paternal as compared to when it was used as maternal parent. This study demonstrates stable inheritance of
the glyphosate resistance trait and the production of fit out crossed offspring in cases of wild type B. juncea × transgenic B. napus. 相似文献
The aim of this work was to carry out the physicochemical and functional characterization of the purified galactomannan obtained
from mesquite seed’s endosperm (MSG). From the seeds, a MSG content of 13/100 g with a purity of 94/100 g was determined.
The dispersions of MSG samples (up to 5 g/100 mL) exhibited a shear thinning non-Newtonian behavior, with 35.68 mPa.s of viscosity,
and surface tension values between 43.5 and 61.06 dynes/cm. The chromatographic analysis revealed a 1.1:1 mannose/galactose
ratio, with a molecular weight between 900,000 and 1,000,000 Da. The calorimetric analysis showed a specific vitreous transition
temperature of 52.92 °C. The values of apparent viscosity were superior to those of commercial galactomannans, which indicates
that MSG can be used too as a thickening agent. The obtained results provide information, which contribute to a better knowledge
of MSG, in order to consider its sustainable exploitation in a future. 相似文献
Origanum × majoricum Cambess. is the most commonly grown oregano in Argentina. The aim of this work was to explore and describe its polyphenolic profile by high-performance liquid chromatography with diode array detection (HPLC-DAD) to support identification by classical microscopy. Remarkable homogeneity was found when defining the HPLC-DAD fingerprint with 17 characteristic common peaks. Eleven spectroscopically identified compounds were located. The method was successfully applied for the characterization of 22 samples from different productive regions of Argentina. The genetic inheritance from both progenitors of this hybrid oregano was evidenced by the presence of compounds coming from Origanum majorana L. and Origanum vulgare L. This method, combined with statistical multivariate analysis, was also useful to recognize two groups within the samples. Although O. × majoricum Cambess. must be considered the only hybrid between two species, two origins considering the subspecies level of O. vulgare L. have been morphologically differentiated for the hybrid, both with O. majorana L. These formulas were differentiated by their HPLC-DAD fingerprints. The Argentine hybrids studied appeared consistently grouped under these two profiles. 相似文献
To investigate the influence of moisture content (MC) and steaming temperature on defects developing during steaming prior to kiln drying, mass loss, heat transfer, microstructures, extractives, and chemical transformation of Eucalyptus grandis?×?E. urophylla specimens (with moisture content of 120, 70, 60, 50, 40, 30, 20%) were observed in this study. Specimens of each experimental moisture content were steamed at 80, 100, and 120?°C for 4 h after pre-heating at atmospheric pressure, respectively. Results revealed that it was most beneficial to conduct steaming at 100?°C when the moisture content was approximately 50% after air drying when stagewise heating-up and continuous steaming schedule were adopted. Under this condition, there was a notable decrease in defects including edge bends, surface splits, and inner splits. Steaming was also a drying period characterized by various extents of mass loss. Changes in microstructures and extractive contents proved the increasing permeability of steamed wood. Deacetylation and crosslinking reactions happened in the hemicellulose of the sample materials, which contributed to the loss of hemicellulose after treatment. 相似文献
This study investigated acceptability and consumer segmentation of soy sauce and famous Korean dish, bulgogi. A total of 123 participants evaluated intensity of 18 attributes and sensory liking of 4 commercial soy sauce samples and bulgogi samples made by aforementioned soy sauces. The overall results showed that appearance liking was the only significant different attribute among soy sauce samples and there were no significant differences among bulgogi samples. Furthermore, there was little correlation between overall liking of soy sauce and bulgogi samples. However, different segments of consumer groups were found by cluster analysis. Four and five subgroups of consumers were identified on evaluation of soy sauce samples and bulgogi samples, respectively. These results demonstrated that consumers’ different preference pattern. In conclusion, this study specified characteristics of commercial soy sauce perceived by consumers and consumers’ acceptability toward soy sauces and bulgogi made using soy sauces. 相似文献
Araça-boi (Eugenia stipitata), bacuri (Platonia insignis) and cupuaçu (Theobroma grandiflorum) are three exotic fruits typical of the Amazonian region. Their pulps are very much appreciated by the inhabitants and have been recently exported. The present paper reports on the chemical composition of these pulps: the gross composition (carbohydrates, protein, fat, ash and dietary fibre contents) has been determined, together with a more detailed analysis of sugars, amino acids, fatty acids and minerals. Altogether, the data indicate that these fruit pulps of Amazonian origin are of nutritional interest and should be promoted at least at a regional level. 相似文献