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101.
102.
为了分析烟草热湿加工处理中的传热过程,通过自行搭建的滚筒干燥过程中烟丝热物性在线测试平台,利用瞬态平面热源法测定了滚筒干燥过程中烟丝的热物性,考察分析了该过程中烟丝温度、含水率对烟丝导热系数、热扩散系数、体积热容的影响。结果表明:①当含水率相同时,烟丝导热系数、体积热容随着烟丝温度的升高而增大,热扩散系数随温度的升高而降低;②当烟丝温度相同时,烟丝导热系数、体积热容随含水率的降低而减小,热扩散系数随着含水率的降低而增大;③干燥过程中,烟丝含水率逐渐减小,烟丝温度逐渐升高,烟丝导热系数在温度与含水率的共同作用下整体有减小的趋势,表明烟丝含水率对导热系数的影响较温度显著。 相似文献
103.
Shrimp head of Penaeus kerathurus obtained from industrial processing, were hydrolyzed by commercial trypsin (0.1%). Hydrolysis reaction was terminated by heat inactivation of the enzyme (95°C) followed by centrifugation. The produced protein hydrolysates were characterized by biochemical analysis for protein content, total free amino acids (FAA), total volatile basic nitrogen (TVB-N) and electrophoresis SDS-PAGE profile. Functional properties such as emulsifying capacity, fat adsorption and foaming property were assessed. Compared to the raw shrimp head protein, results from enzymatic hydrolysis showed a significant increase (p?<?0.05) in protein content and FAA (17.22%). The low level of trypsin used in this study was sufficient to solubilize the substrate, resulting in substantial protein contents and TVB-N levels (< 6mg/100g), which was significantly lower than the acceptable limits established for marine products. 相似文献
104.
Neva Gungor 《International Journal of Food Properties》2013,16(1):44-52
In this study, total phenolic content, antioxidant activity, mineral content and selected physicochemical properties of three white mulberry phenotypes (Morus alba L.) grown in Turkey were measured. Moisture, total soluble solids, total sugar, sucrose, reducing sugar, protein, ash, pH, titratable acidity, color (L, a, b), vitamin C, total phenolic, antioxidant activity of fruits were determined between 72.85–79.75 g/100 g fresh fruit, 21.25–28.50 g/100 g fresh fruit, 12.18–17.02 g/100 g fresh fruit, 1.57–4.36 g/100 g fresh fruit, 9.42–15.46 g/100 g fresh fruit, 0.82–0.89 g/100 g fresh fruit, 2.20–2.65 g/100 g fresh fruit, 5.70–5.86, 0.25–0.28 g/100 g fresh fruit, 31.24–68.69, ?2.46 to 15.68, 4.58–21.74, 10.15–21.50 mg/100 g fresh fruit, 18.16–19.24 μg gallic acid equivalent/mg of sample, and 33.96–38.96%, of sample respectively. Fruits were generally found high in P and low in Ca. 相似文献
105.
Bilal Okmen Hasan O. Sigva Sevgi Mutlu Sami Doganlar Ahmet Yemenicioglu 《International Journal of Food Properties》2013,16(3):616-624
In this study, total water soluble antioxidant activity and phenolic content of 26 eggplant ( Solanum melongena L. ) cultivars were investigated. Total water soluble antioxidant activity of the cultivars varied from 2664 to 8247 μmolTrolox/kg, which is a 3.1-fold difference. Cultivars also showed significant variation for total phenolic contents ranging from 615 to 1376 mg/kg, a 2.2-fold difference. The two traits were significantly correlated and results of this study suggested that breeders can use the information to develop eggplant cultivars with high antioxidant activity. 相似文献
106.
Ali Celik Emine Nur Herken Ahmet Ermis 《International Journal of Food Properties》2013,16(8):1655-1662
Chemical constituents, total phenolic content, total oxidant status, total antioxidant status, lipid hydroperoxides, total free –SH levels, and antimicrobial activity of essential oil obtained from the Ferulago sandrasica (Umbelliferae) were investigated. The essential oil was obtained by hydrodistillation using a Clevenger-type apparatus. The chemical constituents were analyzed by gas chromatography‐mass spectrometry. The main components of the essential oil were ocimene (30.5%), carene-δ-3 (27.4%), and α-pinene (17.8). The antimicrobial activity was tested by a disc diffusion method against E. coli MC 400, E. coli ATCC 25922, E. coli 0157 H7, E. colaecea ATCC 23355, E. feacalis ATCC 19433, P. aeruginosa NRRL B-2679, S. aureus ATCC 25923, B. nischenoformis NRRL B-1001, S. aureus ATCC 33862, B. cereus NRRL B-3711, B. subtilis NRRL B-209, M. luteus NRRL B-1013, L. monocytogenes ATCC 7644, B. subtulis ATCC 6633. 相似文献
107.
A comparative study for the quantitative determination of soluble solids content,pH and firmness of pears by Vis/NIR spectroscopy 总被引:1,自引:0,他引:1
Visible and near infrared (Vis/NIR) spectroscopy was investigated to determine the soluble solids content (SSC), pH and firmness of different varieties of pears. Two-hundred forty samples (80 for each variety) were selected as sample set. Two-hundred ten pear samples (70 for each variety) were selected randomly for the calibration set, and the remaining 30 samples (10 for each variety) for the validation set. Partial least squares (PLS) and least squares-support vector machine (LS-SVM) with different spectral preprocessing techniques were implemented for calibration models. Different wavelength regions including Vis, NIR and Vis/NIR were compared. It indicated that Vis/NIR (400–1800 nm) was optimal for PLS and LS-SVM models. Then, LS-SVM models were developed with a grid search technique and RBF kernel function. All LS-SVM models outperformed PLS models. Next, effective wavelengths (EWs) were selected according to regression coefficients. The EW-LS-SVM models were developed and a good prediction precision and stability was achieved compared with PLS and LV-LS-SVM models. The correlation coefficient of prediction (rp), root mean square error of prediction (RMSEP) and bias for the best prediction by EW-LS-SVM were 0.9164, 0.2506 and −0.0476 for SSC, 0.8809, 0.0579 and −0.0025 for pH, whereas 0.8912, 0.6247 and −0.2713 for firmness, respectively. The overall results indicated that the regression coefficient was an effective way for the selection of effective wavelengths. LS-SVM was superior to the conventional linear PLS method in predicting SSC, pH and firmness in pears. Therefore, non-linear models may be a better alternative to monitor internal quality of fruits. And the EW-LS-SVM could be very helpful for development of portable instrument or real-time monitoring of the quality of pears. 相似文献
108.
Influence of air temperature on drying kinetics and antioxidant potential of olive pomace 总被引:1,自引:0,他引:1
Margarita Hussam Ahmad-Qasem Enrique Barrajon-Catalan Vicente Micol Juan A. Cárcel Jose V. Garcia-Perez 《Journal of food engineering》2013
This work aims to evaluate the influence of olive pomace drying (a solid by-product of the olive oil industry) on both antioxidant potential and drying kinetics. The two main fractions of olive pomace (pits, PI and pulps + peels, P + P) were characterized by image analysis and density measurement. The drying process was analyzed in experiments carried out at different temperatures (from 50 to 150 °C) and mathematically described from the diffusion and Weibull models. The antioxidant potential of the extracts (ethanol–water 80:20 v/v, 22 ± 1 °C, 170 rpm for 24 h) obtained from the dry product was analyzed by measuring the total phenolic content and antioxidant capacity and the main polyphenols were quantified by HPLC–DAD/MS–MS. 相似文献
109.
Flavonoids and saponins from common beans have been widely studied due to their bioactivity. This research evaluated the effect of germination of black beans (Phaseolus vulgaris L.) on the antioxidant capacity and antiproliferative activity against cancer cell lines of saponins and flavonoids extracted from seed coats, cotyledons and sprouts. Principal component analysis was performed to achieve punctual associations between the black bean saponins and flavonoids concentrations to the antioxidant capacity and the antiproliferative activities. Total phenolic content and antioxidant capacity of extracts were higher when obtained from seed coats, mainly from the 3rd germination day. The extracts obtained from seed coats after 3 and 5 germination days inhibited all cancer cell lines proliferation with no cytotoxicity against control cells. Genistein was related with the activity against mammary cancer cells but flavonols and group B saponins were more related with hepatic and colon cancers. Non-glycosilated flavonols were related with antioxidant capacity. 相似文献
110.