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为准确测定烟草及其制品中各种纤维素含量,优化了洗涤剂法的前处理条件,并定量分析了烟叶及烟草制品中中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)和酸性洗涤木质素(ADL)。结果表明:1)前处理中用苯、乙醇、乙醚混合溶剂回流4 h能除去绝大部分酯溶性的干扰物质;2)使用高温淀粉酶能够消除烟叶中淀粉对中性洗涤纤维检测带来的干扰;3)NDF、ADF、ADL检测限分别为0.26%、0.17%、0.17%,回收率为89%-101.4%;4)不同类型烟叶原料之间NDF和ADF含量的差异明显高于不同类型卷烟之间的差异;5)烟草及烟草制品的ADL含量基本都在3%以下。  相似文献   

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The major American tobacco companies developed and agreed to abide by the Cigarette Advertising Code in 1964. The stated aims of the code were to prohibit advertising directed at young people, to prohibit advertising that used fraudulent health claims, and to assure compliance with the code's provisions through the establishment of an administrative arm and enforcement mechanism to prescreen and monitor all cigarette advertising. In the 32 years since the Cigarette Advertising Code's adoption, the tobacco industry has used the existence of this code and its revisions and promises of self- regulation in accordance with this code as evidence that it promotes tobacco use only in a responsible manner. The code has served as the basis of the industry's efforts to avoid further local, state, and federal regulatory oversight of its marketing activities. A historical review of cigarette advertising since 1964 indicates that the voluntary code's major provisions have been regularly violated in the spirit and the letter. The administrative and enforcement provisions of the original Cigarette Advertising Code were quietly dismantled soon after the voluntary code's adoption and were completely omitted from the revised code in 1990. The historical evidence indicates that self- regulation of cigarette advertising and promotion by the tobacco industry has been repeatedly given trials and has not worked.


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In the article the questions of fluoroplastes destruction, opportunity of migration in foodstuff non-polymerized monomers, additives and chemical substances formed as a result of thermal disintegration of polymer are considered.  相似文献   

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Introducing concentrated solutions of preservatives (CSP) provides a methodology both for the use of preservative systems and for their routine control in cosmetic products.
From some typical examples, characteristics of such CSP are described and it is shown how the accurate determination of every component present in the initial liquid blend eliminates the tedious determinations in the finished product where only a single analysis of one preservative is necessary.
Quick and simple methods are described for the analysis of CSP containing parabens, Germall 115® and Kathon CG®. An appropriate new analytical approach is given for routine controls without any tedious extraction and /or costly equipment.
In addition it is shown how this methodology provides a number of substantial advantages at every step of development of new products, storage of raw materials and manufacturing, leading to increased safety and ensuring energy and time savings.
Les mélanges liquides concentrés de conservateurs: leur intérêt technologique et analytique dans les produits cosmétiques  相似文献   

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  目的  为解决机制雪茄香气不足、口感发苦、余味不适的问题,开发一种具有雪茄香韵风格特征、适用于机制雪茄加香的复合焦甜香料。  方法  优化提取溶剂并制备雪茄烟末提取物,将提取物添加于葡萄糖焦糖化反应体系中制备复合焦甜香料,利用GC-MS测试和感官评价阐明反应规律和加香作用特点,并进行制备工艺优化。  结果  (1)雪茄烟末以石油醚提取为优,石油醚提取物的总香味成分含量显著高于无水乙醇和50%乙醇提取物,石油醚有助于雪茄烟末萜烯类和油脂类成分的提取。(2)复合焦甜香料的优选制备工艺为:葡萄糖反应液温度达到180℃时加入石油醚提取物,物料质量比为石油醚提取物: 葡萄糖= 2:10,持续反应3 min。(3)GC-MS分析和感官评价表明,复合焦甜香料主要含有5-羟甲基糠醛(5-HMF)、糠醛、2, 3-二氢-3, 5二羟基-6-甲基-4(H)-吡喃-4-酮(DDMP)等焦甜香韵成分以及烟碱、二氢猕猴桃内酯、新植二烯等烟草本香成分,以焦甜香韵成分为主,其加香效果优于单一的葡萄糖焦甜香料和雪茄烟末石油醚提取物。(4)香气和余味轮廓分析表明,复合焦甜香料能显著增强机制雪茄的焦甜香韵,略微增加清甜、蜜甜和烘烤香,并能明显改善甜润度和刺激感等余味指标。  结论  复合焦甜香料能增加机制雪茄香气量,且能改善余味,适用于机制雪茄加香,优选的添加量为0.4%。   相似文献   

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OBJECTIVE—To examine how deeply foreign cigarette advertising had penetrated the Chinese market when a new ban on cigarette advertising was enacted in February 1995.DESIGN—A survey using self-completion questionnaires administered in college classrooms from November 1994 to March 1995.SETTINGS—Eight universities and four medical schools in three Chinese cities: Beijing, Wenzhou, and Hangzhou.SUBJECTS—1896 college students who agreed to complete a written questionnaire. The mean age was 21.2 years; 39.5% of respondents were female.RESULTS—Four of the top eight cigarette brands most familiar to the respondents were foreign: Marlboro, 555, Kent, and Hilton. Advertisements for the foreign brands were much more likely to be seen than those for the domestic brands; those for Marlboro were reported most often (29.7%), followed by 555 (21.8%) and Kent (18.1%). Among smokers, Marlboro was the most preferred foreign brand, by 44.2%. The preference for Marlboro was also correlated with smokers having seen its advertisements. Most respondents, 71.8%, believed that cigarette advertising should be banned.CONCLUSIONS—The previous restrictions on cigarette advertising in China failed to prevent a large portion of the population from seeing and understanding the advertisements. Before the 1995 advertising ban took effect, strict limitations on imports of foreign cigarettes notwithstanding, certain highly advertised brands such as Marlboro achieved wide recognition and even consumer preference. Stricter restrictions are suggested as previous ones have failed to achieve their intended effects.  相似文献   

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This research was conducted to determine the biogenic amine (BA) and ethyl carbamate (EC) concentrations in commercial Primitivo wine samples and the influence of the use of malolactic starter culture on concentrations of these potentially hazardous compounds in this wine. One hundred sixty bottles of wine from eight producers in the Apulia region of southern Italy were purchased at retail and analyzed. The most common BAs were histamine, 2-phenylethylamine, tyramine, cadaverine, putrescine, spermine, and spermidine. Putrescine (derived from ornithine) was the most abundant BA in all commercial Primitivo wines (5.41 to 9.51 mg/liter), 2-phenylethylamine was detected in only two commercial wines (at less than 2.12 mg/liter), and histamine was found at concentrations of 1.49 to 16.34 mg/liter. The concentration of EC in commercial Primitivo wine was 6.81 to 15.62 ppb, which is not considered dangerous for human health. Malolactic fermentation (MLF) affected the concentrations of BAs and EC differently. For EC, no significant differences were detected between samples of wine produced by spontaneous fermentation and wine that was inoculated malolactic starter. Mean EC concentrations were 12 and 14 ppb in two batches tested (always 18 ppb or less), regardless of whether the malolactic starter was added. Although present at trace levels in wine before the MLF, histamine accumulated during the MLF process, regardless of whether the malolactic starter was added. However, the increase in histamine was higher in wines without the malolactic starter. The concentrations of putrescine and cadaverine increased after MLF, especially in the wine that spontaneously fermented. The use of a selected malolactic starter resulted in reductions in BA concentrations in wine produced by this guided MLF compared with wine produced by spontaneous MLF.  相似文献   

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ABSTRACT

Parabens (PBs) are preservatives frequently used in cosmetics and personal care products as well as in the pharmaceutical and food industries due to their extensive defence mechanisms against multiple categories of microorganisms. Although they are considered safe when used within defined concentration limits, concern about their potential toxicity is still particularly active. Revealed as emerging pollutants, their incidence and behaviour in the aquatic environment have been studied, but there is only sporadic information when it comes to their extent and distribution in seafood. This study explores the presence of methyl- (MeP), ethyl-, propyl-, butyl-, and benzylparaben and their main degradation product 4-hydroxybenzoic acid (pHBA) in several fish species and bivalve samples with the aim to evaluate these food matrices as potentially important contamination sources of PB. Additionally, infant food containing fish was also enrolled in this survey: firstly, due to the absence of any information regarding this exceptionally important food item, and secondly, because of the necessity to estimate the PB content in the processed food. For this purpose, a fast, reliable and robust method was developed based on a simple liquid–liquid extraction followed by high-performance LC, coupled with a benchtop Q-Exactive Orbitrap high-resolution MS. The Q-Exactive parameters were carefully scheduled to achieve a balance between the optimal scan speed and selectivity, considering the limitations that are associated with generic sample preparation methodology. The method was validated through specificity, linearity, recovery, intra- and inter-day repeatability, LOD and LOQ. LOD and LOQ reached the ranges 0.65–3.5 and 2.15–11.7 ng g?1, respectively, while overall recovery ranged from 77% to 118%. The PBs were more frequently present in bivalves than in fish samples with MeP as the main PB detected. No PBs were found in infant food, but pHBA was observed in all samples.  相似文献   

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Quinoa (Chenopodium quinoa) is a valuable source of protein in some parts of South America, and it is likely to be exploited further in both developing and industrialised countries. However, quinoa seeds contain significant levels of saponins which are potential antinutrients. In the present study, the effects of processing on the quantity and composition of saponins in quinoa products were determined, and the biological effects of quinoa grain and cereal products containing high or low levels of saponins were investigated both in vitro and in vivo in the rat. Quinoa saponins were shown to be membranolytic against cells of the small intestine and to cause an increase in mucosal permeability in vitro. Unwashed bitter quinoa caused a significant food aversion and poor food conversion efficiency in rats. However, processing quinoa, during the manufacture of an infant cereal, reduced the concentration and membranolytic activity of saponins, and increased the palatability and nutritional quality of the cereal product to a level similar to that of a wheat-based cereal product.  相似文献   

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Technical‐grade egg albumen (TA) and whole egg (WE) by‐products are produced in substantial quantities by egg‐breaking facilities across North America. TA and WE products are recovered during processing but are not approved for human consumption. Both products are known to be rich in fat, maternal antibodies, protein and lysozyme, a bactericidal enzyme. The objective of this research was to explore the potential for egg by‐products to be used as a valuable protein, energy and bactericidal supplement in animal nutrition. To improve the nutritive value of TA and WE, spray‐dried samples were heat treated at various temperatures and their digestible protein content was determined in vitro using a pepsin/pancreatin digestion/dialysis system. In addition, enhancement of lysozyme activity towards Gram‐negative bacteria (GNB) by heat or irradiation was examined. Optimal protein digestibility for TA averaged 80% following heat treatment at 105–110 °C for 10 min. In contrast, protein digestibility of spray‐dried TA was only 55%. Heat treatment (100–122 °C) of spray‐dried WE or hot room storage of spray‐dried TA and WE products at 70 °C for up to 14 days had a minimal effect on protein digestibility in vitro. Heat treatment or γ‐irradiation of lysozyme for at least 20 min at 80 °C or 0.5 kGy, respectively, increased antimicrobial activity towards GNB. When compared with either the heat or radiation control treatments, reductions in Escherichia coli and Salmonella enterica serovar Typhimurium populations increased by at least 1 and 0.5 log10, respectively. In contrast, the effect of irradiation (2 kGy) on the antimicrobial activity of spray‐dried TA was less pronounced. In a feeding trial, rats fed spray‐dried TA and spray‐dried TA subjected to either radiation (1.8 kGy) or heat (80 °C, 20 min) treatment exhibited a body weight gain and protein utilisation equal to or higher than the control (casein diet). In contrast, feeding spray‐dried WE or TA and WE previously maintained in a hot room (70 °C) for 3 days had a negative effect on rat growth and protein utilisation. In the case of WE products this was substantiated by poor digestibility of essential amino acids, including lysine, threonine and, to some extent, methionine. When compared with the control treatments, inclusion of heat‐treated or irradiated TA in the rat diets reduced the population of Enterobacteriaceae. Copyright © 2006 Society of Chemical Industry  相似文献   

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发酵乳制品因发酵而发生结构和质地改变,并产生独特营养物质,且具有特殊的风味和营养特点,对中老年人健康具有较多健康益处。基于全球队列研究的相关证据,本文综述了发酵乳制品摄入与中老年人群超重/肥胖、心脑血管疾病、糖尿病前期和糖尿病、认知、肿瘤发生间的相关性,以及发酵乳制品潜在健康作用机制的研究进展。  相似文献   

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Vitamin E consists of four tocopherols (α-, β-, γ-, and δ-tocopherol) and four tocotrienols (α-, β-, γ-, and δ-tocotrienols), collectively referred to as tocochromanols or tocols. Tocols are well-known for potent antioxidant, anticancer, anti-inflammatory, immuno-stimulatory and nephroprotective properties. For human nutrition, diet is the major source of tocols (vitamin E) in the body. Thus, there is a need to analyze the different forms of tocols in the diet for the recommendations and to monitor the intake in the body accurately. Several methods have been developed for effective extraction, selective chromatographic separation and sensitive detection of tocols in food. Major advancements also have been made in the field of mass spectrometry for high throughput analysis of primary and secondary metabolites in fruits, vegetables, and grains. This review discusses the theoretical aspects and modern developments in methods of extraction, chromatographic separation, and detection of tocols in plants and their products. Additionally, future research challenges in this perspective are also identified.  相似文献   

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本实验分析了青枯菌侵染前后3个烤烟品种不同叶位的过氧化物酶(POD)活性变化,结果表明,烟株感染青枯病后,叶片POD活性呈上升趋势;在烟株未发病与发病的前中期,抗病品种各叶位的POD活性高于感病品种;在青枯病发病后期,抗感品种间的POD活性无明显差异.因此,POD活性的高低可作为品种对青枯病抗性鉴定的指标.  相似文献   

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