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排序方式: 共有613条查询结果,搜索用时 437 毫秒
61.
Prakash Kumar Nayak Chandrasekar Chandra Mohan 《Chemical Engineering Communications》2018,205(9):1261-1273
In the present work, the impact of microwave pretreatment on the thermal degradation of color (chlorophylls) in mustard greens was studied. The drying experiments were conducted in the range of temperatures from 50 to 80°C. The degradation in the levels of chlorophylls has been quantified using Hunter color values (L*, a*, and b*) and calculating total color difference (ΔE). From the color results, the changes in color values (L*, a*, and b*) were observed as inappreciable, and changes in ΔE were found to be increased during drying. Analysis of kinetic data displayed a first-order reaction kinetics for chlorophyll degradation. Arrhenius equation was used to calculate the activation energies for rate constants, and it has been varied from 13.3 to 27.4?kJ/mol. Thermodynamic parameters, enthalpy of activation (ΔH#), and entropy activation (ΔS#) were found to be in the range of 1.40–2.63?J/mol and ?293 to ?305?J/mol?·?K, respectively. The data from the present work revealed that the microwave pretreatment of mustard greens remarkably influenced the retention of chlorophylls in the final dehydrated powder. 相似文献
62.
Rebecca M. Webster 《Planning Theory & Practice》2016,17(1):9-34
Land use planning in indigenous communities often takes place within state-based planning initiatives, leaving indigenous governments to serve as token participants. Through these initiatives, state-based governments have the ability to wield their power and control the planning process to the detriment of indigenous governments. This study sets forth an alternative option involving cooperative land use planning practices where neither government controls the planning process. Drawing upon a case study of the Oneida Reservation in Wisconsin, USA, this study explores ways to increase cooperative land use planning relationships between indigenous and state-based governments. As one of the few empirical studies to apply critical planning theory to advocate for increased cooperative land use planning, this paper proposes a series of recommendations that can help indigenous and state-based governments avoid conflicts and work toward cooperative relationships. 相似文献
63.
Kamaljit Moirangthem David Jenkins Priya Ramakrishna Ranjana Rajkumari David Cook 《Journal of the Institute of Brewing》2020,126(1):35-45
Indian black rice (Chakhao Poireiton) is a pigmented variety, rich in anthocyanins and other phytonutrients. With growing interest in the use of local raw materials in brewing, it was of interest to develop protocols for malting and brewing with Chakhao Poireiton to see whether the antioxidant capacity of anthocyanins could be delivered into finished beer. Protocols for brewing with 100% malted rice were developed and the performance of Indian black rice compared with that of an Italian white rice cultivar suited to brewing. The apparent fermentabilities of rice worts were 69.5% (black) and 67.3% (white), yielding beers of 3.28 and 3.19% ABV respectively. Black rice worts were deficient in free amino nitrogen (83.5 mg/L relative to 137 mg/L for white rice) and would need nitrogen supplementation to avoid issues with fermentation, e.g. elevated diacetyl. Black rice beer had an orange-red hue as a result of extraction of anthocyanin pigments (2.84 mg/L). The oxidative stability of 100% rice beers was measured using electron spin resonance spectroscopy and both samples were found to be unusually stable. Interestingly, when rice beers were blended with a control barley malt derived lager in varying proportions (10, 25, 50%), the oxidative stability was improved, relative to the control lager, particularly so in the case of black rice beer, which contained an antioxidant capacity over and above that of the white rice beer. Future studies are required to determine whether the noted oxidative stability of 100% rice malt beers results in a more flavour-stable beer. © 2019 The Institute of Brewing & Distilling 相似文献
64.
Deven A Jogdeo Keshvan Niranjan Vishwas G Pangarkar 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2000,75(8):673-680
This paper describes the results of a study on use of the adsorption–regeneration technique for recovery of dissolved allyl isothiocyanate(AITC) which is present in significant quantities in steam distillation condensate of mustard essential oil (MEO). Equilibrium and dynamic breakthrough studies were carried out. The adsorbents used were polymeric adsorbents: Amberlite XAD‐2, Amberlite XAD‐4, Amberlite XAD‐7, NPA‐1 and NPA‐2. The results obtained indicate that Amberlite XAD‐4 is the best amongst these various adsorbents. AITC recoveries in excess of 95% were obtained, indicating the feasibility of this approach. Further, since no chemical reactions are involved the recovered AITC retains its ‘natural’ origin. © 2000 Society of Chemical Industry 相似文献
65.
Malakiba Sen Dipak Kumar Bhattacharyya 《European Journal of Lipid Science and Technology》2000,102(12):727-733
The effect of removing anti‐nutritional factors from n‐hexane‐extracted mustard meal using 80% isopropanol (to reduce thioglucosides, phenolics, etc.) on growth, food efficiency ratio, serum and liver lipid profiles and protein content of young rats was examined. For this n‐hexane‐extracted mustard meal was extracted with 80% isopropanol giving a fraction with 68% protein and low residual thioglucoside (0.5%) as well as phenolic (0.3%) content. This isopropanol‐extracted mustard seed protein fraction reduced the growth of young rats slightly when compared with casein. The food efficiency ratio between rats fed isopropanol‐extracted mustard seed protein or casein did not differ, nor did the protein composition affect serum total cholesterol, triglyceride, HDL‐cholesterol, LDL‐cholesterol, VLDL‐cholesterol and LDL‐C/HDL‐C ratio. However, rats fed isopropanol‐extracted mustard seed protein showed a significantly lower (p<0.05) liver cholesterol concentration than rats fed casein. Liver triglyceride and phospholipid concentrations did not differ between rats fed the two proteins, nor was serum protein affected. This study indicates that extraction of hexane‐extracted mustard meal with 80% isopropanol reduced a number of anti‐nutritional factors like thioglucoside and phenolics. Furthermore the nutritional quality of mustard seed protein fraction is comparable to casein in respect to growth, food efficiency ratio, serum lipid and protein concentrations and organ weights. 相似文献
66.
Influence of sulphur mustard (SM), a chemical warfare agent, on mechanical and transport properties of poly(ethyleneterephthalate) (PET) films was investigated. The objective of the study was to assess the agent–substrate interaction. SM induces changes in PET in that the elongation as well as strength of SM-exposed films decreases considerably. The reduction in percentage elongation at break is very significant, perhaps because of the antiplasticizing effect of SM on PET. The breakthrough time (BTT) of SM is higher for the film, which showed greater resistance to amine etching. The critical dissolution time measurement substantiates the data on mechanical behaviour of SM-exposed films. © of SCI. 相似文献
67.
包装方式对榨菜品质和保藏特性的影响 总被引:2,自引:0,他引:2
以三腌完成的榨菜为原料,加入辣椒、花椒、糖、食用油等进行调味,选用透明(塑料袋)真空包装、不透明(铝箔袋)真空包装、透明充氮包装和不透明充氮包装4 种方式对成品榨菜进行包装。对室温(25 ℃)条件下保藏的榨菜进行品质和保藏特性的研究。结果表明:在75 d保藏期内,透明包装的褐变度、总酸含量、亚硝酸盐含量、菌落总数要高于不透明包装,透明包装的色泽、硬度、感官均低于不透明包装;充氮包装榨菜的硬度、总酸含量、感官评价高于真空包装,褐变度和菌落总数低于真空包装。不透明充氮的各项指标均优于其他包装方式,可以较好地保持榨菜的品质。 相似文献
68.
69.
BACKGROUND: Escherichia coli O157:H7 can survive commercial manufacture of some uncooked fermented meats. External application of microencapsulated allyl isothiocyanate (AIT) or hot (non‐deheated) yellow mustard powder was used to inactivate the pathogen during dry‐cured Westphalian ham manufacture. RESULTS: Within 45/80 days, E. coli O157:H7 numbers were reduced 5 log10 CFU g?1 by 400 µg kg?1 AIT or 60 g kg?1 mustard powder, but 80 days were required in the untreated control. Mustard powder but not AIT reduced numbers of lactic acid bacteria and staphylococci. Mustard powder or ≥ 300 µg kg?1 AIT inhibited yeasts and moulds but did not affect ham pH or water activity. CONCLUSION: The commercial Westphalian ham process without AIT or mustard powder treatment was validated capable of reducing E. coli O157:H7 5 log10 CFU g?1. Surface treatments with ≥ 300 µg kg?1 microencapsulated AIT or 60 g kg?1 yellow mustard powder reduced the time required for this reduction by 40–50%. AIT volatility from microcapsules or hot mustard powder during application of these compounds may restrict their use in production facilities. Copyright © 2009 Society of Chemical Industry 相似文献
70.
Indian borage (Plectranthus amboinicus) was investigated for antifungal activity through agar well diffusion assay. Indian borage oil (IBO) was found to be effective against various fungi tested, as it inhibited the radial growth of mycelia and exhibited broad fungitoxic properties against Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus CFR 221, Aspergillus oryzae, Candida versatilis, Fusarium sp. GF-1019, Penicillium sp., and Saccharomyces cerevisiae. The effective concentration of IBO on the growth of A. ochraceus in yeast extract sucrose medium was determined. IBO completely inhibited ochratoxin (OTA) production by the toxigenic strain A. ochraceus at 500 ppm. Also, the application of IBO at 100 mg/g in food samples resulted in inhibition of the growth of A. ochraceus in food systems such as groundnut, maize and poultry feed and no detectable amount of OTA was found at a high moisture level of 30%, even after seven days. IBO has the potential for use as a botanical fungitoxicant against fungal attack in stored food commodities. 相似文献