细化搜索
结果 1-10 的 647
Rheological properties of freeze-dried wheat starch/galactomannan gels
2004
Juszczak, L. | Fortuna, T. (Krakow Agricultural University (Poland). Dept. of Analysis and Evaluation of Food Quality) | Witczak, M. (Krakow Agricultural University (Poland). Dept. of Engineering and Machinery for Food Industry) | Dymel, A. (Krakow Agricultural University (Poland). Dept. of Analysis and Evaluation of Food Quality)
The objective of the present work was to determine the effect of galactomannans (guar and carob) on some rheological properties of freeze-dried wheat starch gels. Temperature-dependent apparent viscosity curves, flow curves, shear time-dependent apparent viscosity curves as well as mechanical spectra were plotted. On the basis of the results obtained, it can be said that both freeze-drying and gum addition to the system modify rheological properties of wheat starch pastes/gels, and that these changes depend on the type and concentration of the gum used. In the investigated systems with galactomannans, higher values of apparent viscosity were observed along with increasing temperature as well as higher values of shear stress in the flow time, as compared to native starch. It should be stressed, however, that the guar gum system was characterised by higher viscosity values than that with carob gum. The presence of particular gums in the systems modified also viscoelastic properties of gels obtained, depending on the gum used and its concentration
显示更多 [+] 显示较少 [-]Evaluation of grassland quality
2004
Novak, J.,Slovak Univ. of Agriculture in Nitra (Slovak Republic). Faculty of Afrobiology and Food Resources, Dept. of Grassland Ecosystems and Fodder Crops, Tr. A. Hlinku 2, 949 76 Nitra
Evaluation of grassland quality was verified over ten years in 1,200 floristic analyses of grassland in the Western Carpathians. The quality of grassland can be understood on the base of floristic analysis. This analysis consists of the dominance (D) of individual species in floristic groups (in %): Monocotyledoneae - grasses (Poaceae), Monocotyledoneae - sedge and rush family (Cyperaceae + Juncaceae), Monocotyledoneae - families Liliaceae, Orchidaceae and Iridaceae, Dicotyledoneae - leguminous plants (Fabaceae), Dicotyledoneae - other families of dicotyledonous species, Pteridophyta - pterydophyte ferns (Aspidiaceae, Equisetaceae, Hypolepidaceae), and the rest constituted by Bryophyta (mosses) with a share of empty places, and their forage value (FV) in the grassland within the scale from -4 to 8. Evaluation of grassland quality (EGQ) oscillates within the range from minus values (toxic), through deleterious, worthless, low values, lower values, valuable, high values to top values of grassland with maximum value of 100. It can serve for the research and practical survey of the quality of pasture and meadow grasslands. The advantage of the given evaluation in comparison with the other types is the wider scale of forage values, simplicity of calculation and practical use of 100 point scale. The evaluation of grassland can give a clue for the general or partial reconstruction, eventually revitalisation to increase forage value. There must be made a compromise between aesthetic and feeding value of grassland. As the high portion of aesthetic species has low feeding value, and does not meet the requirements for animal nutrition, it is necessary to revitalise the grasslands by the additional seeding of valuable or high valuable species, accordingly to the intensity of use, even to the detriment of aesthetic value of the grassland.
显示更多 [+] 显示较少 [-]Quality evaluation of soybean using germination percentage for tofu production
2004
Suehara, K. (Hiroshima City Univ. (Japan). Faculty of Information Sciences) | Shimizu, S. | Toshimori, D. | Koda, M. | Mizunari, Y. | Terada, T. | Kakumoto, T. | Yano, T.
In the tofu production process, quality evaluation of soybean is most important to control the tofu quality at a constant because the quality of soybean directly affects the quality of the product In this study, the germination percentage of soybean was selected as an indicator of the quality evaluation of soybean for tofu production. Effects of storage temperature and relative humidity on the germination percentage of stored soybean, the protein contents of soybean, soymilk and tofu refuse, soymilk Brix and hardness of tofu were examined. The protein contents of soybean and soymilk were not suitable as indicators for the quality evaluation of soybean because the protein contents were'unchanged. It may be important to measure the quality of the protein because the quality of soybean may change during soybean storage. The germination percentage was suitable as an indicator for the quality evaluation of soybean because the hardness of tofu could be predicted from the germination percentage of the soybean. The quality evaluation of the soybean using the germination percentage and the soymilk Brix (protein content of soymilk) was possible.
显示更多 [+] 显示较少 [-]Roadmap to evaluation of cotton's processing quality
2004
Robert, K.Q.
This purpose of this work is to lay down a technical research strategy by which the utility value of cotton as a raw material for textile processing can be defined and predicted from measured fiber properties. From the time a cotton is harvested, a series of opening and cleaning mechanisms are applied, both before and after ginning. This sequence is continued in the textile mill as the crucial aspect of the opening-cleaning, blending, and alignment of fibers which constitutes preparation for spinning. Opening and cleaning principles and machinery employed in the gin and mill are sufficiently similar to allow for a unified description of the cotton cleaning process. The governing principle is that to be cleaned to a given degree of fineness of foreign matter, the cotton must be opened to that level of fineness. In the present work, a mathematical framework is proposed for describing cotton cleanability as a trade-off between the reduction of foreign matter on the one hand, and the amount of mechanical damage which on the other hand must necessarily be inflicted upon the cotton to achieve that level of opening. If indices of cleaning and damage are appropriately defined, then cleaning is modeled mathematically as an algebraic extinction process, while damage can be viewed as a saturation process. Most importantly, the trade-off between cleaning and damage can be shown to have certain systematic features which can be utilized to characterize the processability of a cotton and to predict optimum processing strategies. A significant feature of this analysis is that it demonstrates how a cotton bale's processing (ginning and mill preparation) history influences its performance in downstream operations such as spinning.
显示更多 [+] 显示较少 [-]Technological evaluation of introduced Virginia type tobacco varieties
2004
Nikolov, N. | Nikolova, V. (Tobacco and Tobacco Products Institute, Plovdiv (Bulgaria))
The variety structure improving of Virginia type tobaccos growing in Bulgaria has big importance as well as for growers and like raw for tobacco products production. The aim of present investigation is technological evaluation of type Virginia introduced tobacco varieties and their quality comparison with widely distributed local variety. A one year test shows, that in respect of main quality indexes by which the evaluation is made chemical composition of tobacco and tobacco smoke, physical indexes, expert and smoking evaluation / it can't determine better quality of introduced varieties. The results for control (local) variety are better in many relations. It is necessary additional investigation (repetition) for one crop at least.
显示更多 [+] 显示较少 [-]Quality evaluation of commercial extracts of Scutellaria baicalensis
2004
Ye, F. | Wang, H. | Jiang, S. | Wu-O, Jess | Shao, J. | Cheng, X. | Tu, Y. | Zhang, D.Y.
Botanical products have been widely used for various illnesses and general well-being. However, quality control of botanical products is often not performed due to lack of standardization, resulting in inconsistent efficacies and sometimes serious toxicity. The goals of this study were to determine the correlation between chemical composition and biological activities and to establish a method to measure authenticity, chemical consistency, and biological potency of botanical products. A high-performance liquid chromatography method was used to analyze the authenticity and chemical composition of 10 different commercial extracts. The cell viability assay and prostaglandin E2 (PGE2) enzyme immunoassay were used to analyze biological potency and consistency. Our results showed all extracts contained marker components (baicalein and/or baicalin), confirming their authenticity. However, significant product-to-product and batch-to-batch variation of these marker components was observed with 4 products containing no baicalin at all and baicalein concentration ranging from 0 to 52.3 microgram/mg. The 50% growth inhibition concentration of the extracts ranged from 0.18 to 2.0 mg/ml, more than an 11-fold variation. PGE2 levels varied from 19.5 to 111.1 pg/10(6) cells, more than a 5.7-fold difference. These results demonstrated significant variation in chemical composition and biological activities of the commercial extracts and that the amount of marker components may not reflect biological activity levels. Therefore, chemical analysis alone is inadequate for quality control, and biological assays must be included for botanical products to ensure chemical authenticity as well as pharmacological/biological potency and consistency.
显示更多 [+] 显示较少 [-]Meat quality evaluation by computer vision
2004
Tan, J.
Applying computer vision in meat quality evaluation has been an active area of research in recent years. Various studies have addressed issues from basic technique development to applications. This paper summarizes the main results from a number of recent application studies, which include characterization of quality attributes such as color, marbling, maturity and texture; prediction of sensory scores and grades; and prediction of cooked-meat tenderness. The promise of computer vision for objective meat quality evaluation is demonstrated and the remaining challenges are discussed.
显示更多 [+] 显示较少 [-]ИНДЕКС "БИОЛОГИЧЕСКОГО КАЧЕСТВА" В ОЦЕНКЕ ЭКОЛОГИЧЕСКОГО СОСТОЯНИЯ ПРИБРЕЖНЫХ АКВАТОРИЙ | Use of the Biological Quality Index for an evaluation of area water ecological state
2004
Алемов, С. В. | Осадчая, Т. С.
The data on evaluation of bottom environment "biological quality" with apply of the "Biology Quality Index" (BQI) widely used by western researches are given. An expediency of comprehensive approach (on the basis of chemical and biological data) for an evaluation of bottom environment ecological state of any offshore strip is shown. | Приведены данные по оценке "биологического качества" донной среды с применением широко используемого западными исследователями "The Biology Quality Index" (BQI). Показана целесообразность комплексного подхода (на базе химических и биологических данных) в оценке экологического состояния донной среды любой прибрежной акватории.
显示更多 [+] 显示较少 [-]Quality evaluation of fresh-cut "Tommy Atkins" mangoes
2004
Vilas Boas, B.M. | Nunes, E.E. | Fiorini, F.V.A. | Lima, L.C. de O. | Vilas Boas, E.V. de B. | Coelho, A.H.R.
Evaluation of diet quality with the mediterranean dietary quality index in university students
2004
Šatalić, Zvonimir | Barić, Irena Colić | Keser, Irena | Marić, Bernard
Data on diet quality in Croatian university students have been missing for more than 15 years. A food approach rather than a nutrient approach appears more appropriate to present knowledge on diet and health. The aim of the present study was to evaluate diet quality in Croatian university students (n=663) with the Mediterranean Dietary Quality Index (M-DQI) in continental and Mediterranean regions. The M-DQI was determined with a Quantified Food Frequency Questionnaire. The minimum score for the M-DQI is 0 and the maximum score is 14. A higher score indicates a less healthy diet. The score for the M-DQI was the same in both regions (9.6) and did not differ significantly. In the category for scores 8–14 were 84.0% and 84.6% of students in the continental and Mediterranean regions, respectively. Higher correlation for the M-DQI was observed with macronutrient intakes than with micronutrient intakes. The M-DQI did not correlate with trans-fatty acid intake. A significant correlation (negative) with lycopene was observed in the Mediterranean region only. The body mass index did not correlate with the M-DQI. Students from both regions, continental and Mediterranean, had a lower diet quality evaluated with the M-DQI, with no significant difference according to region.
显示更多 [+] 显示较少 [-]