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61.
Debranning of wheat affects flour quality, initially by altering the breakage of wheat kernels during first break. The double normalized Kumaraswamy breakage function was applied to model the effect of debranning on wheat breakage during first break milling, in which type 1 breakage describes a relatively narrow distribution of midsized particles, whereas type 2 breakage describes a wide size range of predominantly small particles extending to very large particles. Mallacca (hard) and Consort (soft) wheats were debranned and milled at three roll gaps under sharp‐to‐sharp and dull‐to‐dull dispositions. Type 1 breakage increased at longer debranning times, whereas type 2 breakage decreased, for both wheat varieties under both dispositions. Sharp‐to‐sharp milling tended to produce more type 1 breakage than dull‐to‐dull. A mechanism of wheat breakage is proposed to explain the coproduction of very large and small particles via type 2 breakage and, hence, the effect of debranning. The proposed mechanism is that small particles of endosperm arise from scraping of large flat particles of wheat bran under the differential action of the rolls, such that removal of the bran reduces the production of the large bran particles and thus reduces the opportunity for the scraping mechanism that produces the very small particles. 相似文献
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Supercritical carbon dioxide extraction and characterization of Laurus nobilis essential oil 总被引:5,自引:0,他引:5
Caredda A Marongiu B Porcedda S Soro C 《Journal of agricultural and food chemistry》2002,50(6):1492-1496
Supercritical carbon dioxide extraction allowed essential oil of Laurus nobilis to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 degrees C; and carbon dioxide flow, Phi = 1.0 kg/h. Waxes were entrapped in the first separator set at 90 bar and -10 degrees C. The oil was recovered in the second separator working at 15 bar and 10 degrees C. The main components were 1,8-cineole (22.8%), linalool (12.5%), alpha-terpinyl acetate (11.4%), and methyleugenol (8.1%). Comparison with the hydrodistilled oil did not reveal any significant difference. Collection of samples at different extraction times during supercritical extraction allowed the change of the oil composition to be monitored. Lighter compounds such as hydrocarbon and oxygenated monoterpenes were extracted in shorter times than the heavier hydrocarbon and oxygenated sesquiterpenes. 相似文献
65.
Carlos Agustín Alesso María Josefina Masola María Eugenia Carrizo Pablo Ariel Cipriotti Silvia del Imhoff 《Archives of Agronomy and Soil Science》2019,65(6):822-832
The effect of tillage on soil properties varies within field due to spatial variability of soils. Mapping changes of soil penetration resistance (PR) would be useful to understand and assess tillage practices to alleviate soil compaction. The objectives were to model the short-term effect of tillage on PR and its spatial structure, and to delineate homogeneous zones based on soil response in a Typic Argiudoll previously managed under no-till. A grid sampling for PR and soil water content (SWC) were performed before and after chiselling. Spatial analysis was performed on the effect of tillage on PR data by 10 cm layers and homogeneous zones were delineated by k-means cluster analysis. The effect of tillage was ?0.33 MPa in 10–20 and 20–30 cm layer. No differences of PR were found at 0–10 cm. Short range (5–7 m) spatial structure on the horizontal plane was observed in all layers. Only 45% of the field showed a marked effect of tillage on PR. Mapping the effect of tillage on PR would be a useful approach for evaluating the global and local response of soil to tillage, as well as for delineating of areas within field for site-specific tillage practices. 相似文献
66.
Colombo S Scarampella F Ordeix L Roccabianca P 《Journal of Feline Medicine and Surgery》2012,14(7):498-502
PRESENTING SIGNS: Three Devon Rex cats were presented with multiple erythematous papules, occasionally associated with crusting and hyperpigmentation, with a linear distribution on the head, neck, chest and abdomen. One cat also had multifocal alopecia with hyperpigmentation on the dorsum. DIAGNOSIS AND TREATMENT: Clinical and histopathological features were suggestive of papular eosinophilic/mastocytic dermatitis (urticaria pigmentosa-like dermatitis). In all cases, dermatophytosis was diagnosed: in cases 1 and 2 there was histopathological evidence of dermatophytosis, while fungal culture was positive for Microsporum canis in cases 2 and 3. In all cats, lesions disappeared following antifungal treatment. CLINICAL SIGNIFICANCE: Papular eosinophilic/mastocytic dermatitis in Devon Rex cats may represent either an atypical presentation of dermatophytosis or a clinical and histological reaction pattern to various diseases, including dermatophytosis and allergic diseases. Clinical differentiation is crucial as there are important implications regarding treatment and, in particular, the use of glucocorticoids, which are contraindicated in cases of dermatophytosis. 相似文献
67.
This trial was carried out to study the influence of the nutrient solution on the microelements concentration and distribution in C. fruticosa var. ‘Red Edge' plants. Four treatments were tested: T1 [control, 1.5 dS m?1, 14.3 mmol L?1 sodium chloride (NaCl)], T2 (2.5 dS m?1, 22.2 mmol L?1 NaCl), T3 (3.5 dS m?1, 32.7 mmol L?1 NaCl) and T4 (4.5 dS m?1, 38.2 mmol L?1 NaCl). In roots and stems, iron (Fe) concentrations were lower in the no saline treatment. Stems accumulated more Fe with treatments T3 and T4. Copper concentration and extraction were not affected by salinity. The highest manganese (Mn) concentration in roots was observed in T2, while in petioles was higher in T3 and T4. Manganese extraction reached higher levels in the saline treatments in roots and stems, while in petioles it was lower in T1, T2 and T3. In roots, zinc (Zn) concentration was lower with the extreme treatments. Micronutrients concentration in leaves was unaffected by salinity, because an exclusion mechanism that consists on accumulation in roots and stems was developed. 相似文献
68.
Silvia Evangelista-Lozano Maribel Estrada-García Sandra Luz Escobar-Arellano Martha Lucia Arenas-Ocampo Brenda Hildeliza Camacho-Díaz 《Journal of plant nutrition》2015,38(4):551-567
Eucharis grandiflora Planch. and Linden is a tropical climate Amaryllidacea, commonly known as lily, which develops a bulbous stem and is considered an indoor ornamental plant for its evergreen foliage and inflorescence. The aim of this study was to evaluate the vegetative development of the Lily, in response to the treatment with of the Steiner solution at different concentrations. The plants were acclimated under greenhouse conditions and the bulbs selected by a completely randomized design. Plants were treated with various concentrations of the Steiner solution, to develop the following potential osmotic: ?0.018, ?0.036, ?0.054, ?0.072, and 0 Mpal. The production of bulbils, development and leaf area, stomatal density, chlorophyll quantification, and osmotic potentials were evaluated. The results showed that treatment with solutions of ?0.054 and ?0.072 MPa induced a greater vegetative growth, 29.5% more stomata developed, and synthesized 29% more chlorophyll “b” than the control. 相似文献
69.
Farroni AE Matiacevich SB Guerrero S Alzamora S Del Pilar Buera M 《Journal of agricultural and food chemistry》2008,56(15):6447-6453
The purpose of this work was to analyze the effect of water on thermal transitions, mechanical properties, and molecular mobility in corn flakes (CF), and their relationships. Commercial common (CCF) and sugar-frosted (SCF) corn flakes were studied in a water content (wc) range from 5 to 20 (% dry basis). The slope of (1)H NMR spin-spin relaxation time T 2* (determined by FID) versus temperature plot changed close to T g. Compression force showed a maximum at wc of ca. 12 and 16% (db) for SCF and CCF, respectively. (1)H NMR complemented DSC data in determining the temperature dependence of water and solid mobility, in order to assess quality of laminated corn products. The results of the present work indicate that while the compression force showed a maximum value as a function of water content, T g values determined by DSC or by spin-spin relaxation decreased progressively with increasing water content. 相似文献
70.
Calucci L Capocchi A Galleschi L Ghiringhelli S Pinzino C Saviozzi F Zandomeneghi M 《Journal of agricultural and food chemistry》2004,52(13):4274-4281
Seeds of bread wheat were incubated at 40 degrees C and 100% relative humidity for 0, 3, 4, 6, and 10 days. The effects of accelerated aging on seed germinability and some biochemical properties of flour (carotenoid, free radical, and protein contents and proteolytic activity) and gluten (free radical content and flexibility) were investigated. Seed germinability decreased during aging, resulting in seed death after 10 days. A progressive decrease of carotenoid content, in particular, lutein, was observed, prolonging the incubation, whereas the free radical content increased in both flour and gluten. A degradation of soluble and storage proteins was found, associated with a marked increase of proteolytic activity and a loss of viscoelastic properties of gluten. On the contrary, puroindolines were quite resistant to the treatment. The results are discussed in comparison with those previously obtained during accelerated aging of durum wheat seeds. 相似文献