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1.
This study was conducted to obtain annatto extracts with both high antioxidant capacity and colour potential using solvents of different polarities (water, ethanol/water, ethanol, ethanol/ethyl acetate and ethyl acetate). The highest levels of total phenolic compounds were found in the water, ethanol/water and ethanol extracts (0.5 mg GAE mL?1), and the highest level of bixin was found in the ethanol/ethyl acetate extract (5.2 mg mL?1), which was characterised as the reddest and the most vivid one (a* = 40.5, = 46.1, C* = 58.4). The ethanol/ethyl acetate extract also showed the highest antioxidant activity (4.7 μm TEAC mL?1) and the highest percentage of tryptophan protection against singlet oxygen (63.6%). On the other hand, ethyl acetate and ethanol/water were the least effective solvents for the extraction of phenolic compounds and bixin, respectively. According to the multivariate statistical analysis, ethanol/ethyl acetate and ethyl acetate were the most promising solvents to obtain annatto extracts with both antioxidant and colour properties.  相似文献   
2.
超高效液相色谱法快速检测食品中胭脂树橙的含量   总被引:1,自引:0,他引:1  
本文建立了食品中胭脂树橙含量的超高效液相色谱紫外检测方法.样品采用酸化乙腈溶液提取,提取液经乙腈饱和正己烷萃取净化后注入超高效液相色谱仪,由BEH C(18)柱(1.7μm,2.1×50mm)快速分离后进人紫外检测器检测.本方法胭脂树橙检测限为0.1mg/kg.5种食品样品回收率为83.8%-96.1%,相对标准偏差(...  相似文献   
3.
The development of an analytical method that enables routine analysis of annatto dye, specifically bixin and norbixin, in meat tissue is described. Liquid-solid extraction was carried out using acetonitrile. Analysis was by HPLC with photodiode array detection using two fixed wavelengths (458 and 486 nm). The possibilities of ion trap mass spectrometry (MS) were also assessed. Method performance characteristics, according to Commission Decision 2002/657/EC, were determined, with recoveries between 99 and 102% and calibration curves being linear in the 0.5–10 mg kg?1 range. The limit of quantification was 0.5 mg kg?1.  相似文献   
4.
Colored Cheddar cheeses are prepared by adding an aqueous annatto extract (norbixin) to cheese milk; however, a considerable proportion (~20%) of such colorant is transferred to whey, which can limit the end use applications of whey products. Different geographical regions have adopted various strategies for handling whey derived from colored cheeses production. For example, in the United States, whey products are treated with oxidizing agents such as hydrogen peroxide and benzoyl peroxide to obtain white and colorless spray‐dried products; however, chemical bleaching of whey is prohibited in Europe and China. Fundamental studies have focused on understanding the interactions between colorants molecules and various components of cheese. In addition, the selective delivery of colorants to the cheese curd through approaches such as encapsulated norbixin and microcapsules of bixin or use of alternative colorants, including fat‐soluble/emulsified versions of annatto or beta‐carotene, has been studied. This review provides a critical analysis of pertinent scientific and patent literature pertaining to colorant delivery in cheese and various types of colorant products on the market for cheese manufacture, and also considers interactions between colorant molecules and cheese components; various strategies for elimination of color transfer to whey during cheese manufacture are also discussed.  相似文献   
5.
An innovative dye‐sensitized solar cell based on achiote seeds with a new dual electrical generation mechanism is presented. This dye‐sensitized solar cell, in addition to the well‐known mechanism, where the conduction electrons are released from the dye molecules due to their interaction with photons, shows a distinct chemical mechanism that produces an effective electric current under dark conditions. Both mechanisms operate simultaneously; however, the electrical signal obtained from the photoelectrical mechanism is stronger. Additionally, during a rapid transition from darkness to illuminate conditions, non‐linear oscillations in the current signal are produced when the system is shifted rapidly far from equilibrium conditions. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
6.
目的建立高效液相色谱法测定巧克力中胭脂树橙含量的分析方法。方法采用氨水乙醇提取样品中的色素,石油醚除脂后,在酸性条件下采用二氯甲烷反提取目标物,选用C_(18)色谱柱分离,以乙腈:2%乙酸(75:25,V:V)作为流动相进行等度洗脱,用紫外检测器在458 nm波长检测,外标法定量。结果降红木素的定量限为1.0 mg/kg,红木素的定量限为2.0 mg/kg,线性范围为1~50 mg/kg。降红木素和红木素回收率分别为87.8%~92.0%和88.7%~92.1%,相对标准偏差(relative standard deviation,RSD)分别为1.1%~5.0%和1.7%~5.2%。结论本方法简单、便捷,适用于巧克力中胭脂树橙含量的测定。  相似文献   
7.
该实验建立了超高效液相色谱-四级杆-飞行时间质谱(UPLC-Q-TOF/MS)快速筛查谷物食品中红木素和降红木素的分析方法。样品用5%醋酸乙腈溶液提取后,采用ZORBAX SB-C18色谱柱分离,以乙腈-0.1%甲酸水溶液(含5 mmol/L乙酸铵)为流动相,梯度洗脱,UPLC-Q-TOF/MS电喷雾正离子模式分析检测。以准分子离子峰的峰面积定量,以化合物的色谱保留时间、精确质量数及碎片离子的精确质量数定性。结果表明,红木素和降红木素分别在1.0~70 mg/kg、0.5~70 mg/kg范围内具有较好的线性关系,相关系数(R)均大于0.99,其定量限分别为1.0 mg/kg、0.5 mg/kg,样品的加标回收率在71.5%~110.6%范围内,相对标准偏差(RSD)均不高于10.2%。该方法简便、快速、准确性高,适用于批量谷物食品的快速筛查。  相似文献   
8.
Annatto colorants derived from Bixa orellana L. seeds have been extensively used in a wide range of food commodities such as dairy products, flour confectionery, fish, soft drinks, meat products, snack foods, and dry mixes. To exploit its use as a colorant for textiles, this research study investigates for the first time pre-mordanting of wool with bi and tri metal salt combinations using aluminum potassium sulfate, ferrous sulfate, and stannous chloride mordants in order to develop natural and beautiful shades on wool with variation in hue and tone. The dyeing was carried by exhaustion method and dyed samples were analyzed using a Reflective Spectrophotometer in terms of CIELAB (L*, a*and b*) and K/S values and washing and light fastnesses were investigated according to I.S.O. standard recommendations. In the dyeing experiments, wool samples pre-mordanted with Fe + Sn displayed highest color strength followed by Fe + Al and Al + Sn combinations. The results showed that overall 36 different shades having good to very good fastness properties were produced by the use of different metallic salt combinations in the natural dyeing of wool using annatto dye.  相似文献   
9.
The Cheddar cheese colorant annatto is present in whey and must be removed by bleaching. Chemical bleaching negatively affects the flavor of dried whey ingredients, which has established a need for a better understanding of the primary colorant in annatto, norbixin, along with cheese color alternatives. The objective of this study was to determine norbixin partitioning in cheese and whey from full-fat and fat-free Cheddar cheese and to determine the viability of bixin, the nonpolar form of norbixin, as an alternative Cheddar cheese colorant. Full-fat and fat-free Cheddar cheeses and wheys were manufactured from colored pasteurized milk. Three norbixin (4% wt/vol) levels (7.5, 15, and 30 mL of annatto/454 kg of milk) were used for full-fat Cheddar cheese manufacture, and 1 norbixin level was evaluated in fat-free Cheddar cheese (15 mL of annatto/454 kg of milk). For bixin incorporation, pasteurized whole milk was cooled to 55°C, and then 60 mL of bixin/454 kg of milk (3.8% wt/vol bixin) was added and the milk homogenized (single stage, 8 MPa). Milk with no colorant and milk with norbixin at 15 mL/454 kg of milk were processed analogously as controls. No difference was found between the norbixin partition levels of full-fat and fat-free cheese and whey (cheese mean: 79%, whey: 11.2%). In contrast to norbixin recovery (9.3% in whey, 80% in cheese), 1.3% of added bixin to cheese milk was recovered in the homogenized, unseparated cheese whey, concurrent with higher recoveries of bixin in cheese (94.5%). These results indicate that fat content has no effect on norbixin binding or entrapment in Cheddar cheese and that bixin may be a viable alternative colorant to norbixin in the dairy industry.  相似文献   
10.
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