Silicon compounds as additives improving coating performance: fixation of silicon compounds with cellulose

In this study the reactivity of cellulose with new solvent born preparations containing organosilanes, alkyd resin and natural oil was analysed. Structural analysis of cellulose after reaction with organosilanes and after extraction was performed using Fourier-transform infrared spectroscopy (FTIR). In IR spectra the analyzed bands included 1250 cm^?1 responsible for vibrations of the SiC group and 800 cm^?1 responsible for vibrations of SiC and/or SiO groups. These bands are characteristic of silicon bonds with atoms of carbon and oxygen originating from the methoxy groups found in organosilanes. The presence of these bands in the spectra proves the occurrence of a reaction between cellulose and organosilanes. The concentration of silicon was determined by AAS in cellulose after reaction with preparations and after extraction.     

Use of encapsulated natural compounds as antimicrobial additives in food packaging: A brief review

BackgroundSynthetic chemical preservatives in food can be harmful to human health. These problems have increasingly attracted concern and interest from researchers, which has led to the study and application of non-toxic essential oils with preservative ability in food products and food packaging. A great challenge in this sense is their facile degradation during processing of the food and manufacturing processes during food packing.Scope and approachEncapsulation is an interesting technique to improve the physical-chemical and microbiological stability of these essential oils, as well as to achieve controlled release. This review provides a detailed overview of encapsulation in the food industry, focusing on the application of procedures to encapsulate antimicrobial essential oils.Key findings and conclusionsThis review focuses on recent studies related to nanotechnology and the nano and microencapsulation of essential oils. This study provides valuable insight that may be useful for identifying trends in the commercialization of nanotechnological products or for identifying new research areas. The results published to date confirm that the encapsulation promotes the protection of active compounds, enabling industrial applications of active packaging.     

Application of alginate and gelatin-based edible coating materials as alternatives to traditional coating for improving the quality of pastirma

This research was conducted to study the efficacy of sodium alginate and gelatin coating materials in improving the quality of pastirma. Pastirma was coated with traditional, alginate or gelatin coatings, stored at 4 °C for 4 weeks and examined weekly. Alginate and gelatin coated-pastirma revealed lower TBARS values which was within the acceptable limit (0.67 and 0.86 mg/kg) until the end of storage, however, the TBARS values of traditionally coated pastirma reached 1.33 by the end of storage. Edible coating delayed respiration rate with improvement of the color when compared with traditionally coated one. Oxygen concentration increased from 4.21 mg/kg/h in traditionally coated pastirma to 12.56 and 9.79 in alginate and gelatin coated ones, respectively. Meanwhile, CO₂ concentration decreased from 10.40 mg/kg/h in traditionally coated pastirma to 4.89 and 6.07 mg/kg/h in alginate and gelatin coated ones, respectively. Moreover, a distinct improvement in all sensory attributes has been observed.     

粗粉碎纺织品高粘度涂层组分涂层用内置挤压辊式轧液机

织物增强混凝材料的承载性能由织物的增强基质和混凝基质的复合性能所决定。涂层组分对纱线横截面的完全渗透是复合材料最佳承载强度的先决条件。     

无机助剂整理的棉织物防紫外性能分析

为探究无机助剂浓度与整理时间对棉织物防紫外性能的影响,使用不同质量分数的无机助剂TiO₂对棉织物进行浸渍整理,通过微观结构和紫外性能测试分析试样防紫外性能随浸泡液浓度的变化,探究最佳浓度和最优处理时间。结果表明,TiO₂颗粒物理黏附于棉纤维表面,当助剂质量分数在0～2%时,浓度越高,纤维表面附着的颗粒越密集,对应的紫外线透过率越低;当助剂质量分数超过2%时,纤维上的颗粒附着量达到饱和;TiO₂助剂对棉织物的质量分数为2%、处理时间为1 h时,棉织物具有最佳的防紫外性能。     

不同添加剂对防水透湿涂层整理的影响

 为了改善芳砜纶/棉混纺织物的涂层效果,水性聚氨酯涂层胶中加入添加剂羧甲基纤维（CMC）或海藻酸钠（ALG）;通过对比及分析涂层织物的透湿性、淋雨性和硬挺弯曲长度,添加剂CMC的综合效果优于ALG;在含有CMC涂层胶中加入聚乙二醇（PEG）能显著改善织物的透湿性能以及织物手感;当CMC添加量为0.25%,PEG添加量为10%时,涂层织物的透湿量达到6721.5g/m2.24h,淋雨性为5级,织物弯曲长度为5.51cm,具有较好的防水透湿性能以及织物手感。     

Benzoic acid and its derivatives as naturally occurring compounds in foods and as additives: Uses,exposure, and controversy

Benzoic acid is an aromatic carboxylic acid naturally present in plant and animal tissues, which can also be produced by microorganisms. Benzoic acid and a wide range of derivatives and related benzenic compounds, such as salts, alkyl esters, parabens, benzyl alcohol, benzaldehyde, and benzoyl peroxide, are commonly used as antibacterial and antifungal preservatives and as flavoring agents in food, cosmetic, hygiene, and pharmaceutical products. As a result of their widespread occurrence, production, and uses, these compounds are largely distributed in the environment and found in water, soil, and air. Consequently, human exposure to them can be high, common, and lengthy. This review is mainly focused on the presence and use of benzoic acid in foods but it also covers the occurrence, uses, human exposure, metabolism, toxicology, analytical methods for detection, and legal limits for benzoic acid and its derivatives. Their controversial effects and potential public health concerns are discussed.     

微波浸染染色技术及性能研究

以微波加热,采用浸染方法,研究了活性染料对棉纤维的染色,探讨了元明粉(Na2SO4]、纯碱(Na2CO3)、浴比对微波染色的影响.结果表明:在微波促进下,采用浸染染色时,活性染料可顺利地对棉织物进行染色,元明粉、纯碱、浴比等工艺条件对固色率和上染率都有影响,织物各项色牢度优良.还研究了微波染色后纤维的物理性能.结果表明:织物的撕破强力和拉伸强力都有不同程度的提高,对弹性的影响很小.     

Boron fixation in wood: studies of fixation mechanisms using model compounds and maritime pine

The purpose of the research work reported in this paper was to study the kinetics and thermodynamics of reactions of some boron compounds with some simple wood model compounds and with maritime pine (Pinus pinaster Ait.). The wood model compounds were selected in order to reproduce in a simple way the possible reactions boron may undergo with wood. Two boron compounds were tested with the wood: sodium tetraborate decahydrate (borax) and boric acid. Boron containing solutions applied to wood and model compounds were tested in such a way that they could lead to the insolubilization of boron or to its chemical fixation. Thermodynamics of boric acid fixation on the wood surface was studied. Results suggest that, even though boron reacts faster with polysaccharides than with lignin, all reactions are very slow at 20 °C. Adsorption should be the preferential mechanism for the bonding of boric acid to wood. This weak bond explains why boron tends to leach out from wood in wet conditions after conventional preservative treatments.     

Fate of sulphur compounds released from cellulose xanthate during its action as a soil conditioner

The distribution of the sulphur-containing compounds released from cellulose xanthate after its application to soil has been investigated by laboratory experiments using ³⁵S-labelled cellulose xanthate. It was shown that more than half of the sulphur contained in cellulose xanthate applied to soil was dispersed into the atmosphere, presumably as carbon disulphide. This release occurred rapidly during the first few hours and was virtually complete within 48 h. About 25% of the sulphur added was water soluble, and was leached through the soil by simulated rain. About 20% of the sulphur added remained attached to the soil in an insoluble form, some of it acid resistant. Ageing the cellulose xanthate for up to 14 days at 20°C before application had only minor effects on this fractionation. It is unlikely that the use of cellulose xanthate as a soil conditioner would have any appreciably harmful or unpleasant side effects, or cause damage to the environment.     

The application of additives and compounds to meat products

From the economic and perspective point of view the application of compounds and extenders in meat products represents an unavoidable world-wide development. The present study reviews additives and compounds for sausages and other comminuted meat products which have an influence on water binding and fat emulsifying. In the paper details and results of the patent publications published since 1960 are presented and discussed.     

Determination of isothiocyanates and related compounds in mustard extract and horseradish extract used as natural food additives

Amounts of isothiocyanates and related compounds in a mustard extract and a horseradish extract for food additive use were determined by GC, after confirmation of the identity of GC peaks by GC/MS. Amounts of allyl isothiocyanate, which included that of allyl thiocyanate, because most of the allyl thiocyanate detected in the sample was assumed to have been formed from allyl isothiocyanate during GC analysis, were 97.6% and 85.4%, in the mustard extract and the horseradish extract, respectively. Total amounts of the identified isothiocyanates in the mustard extract and the horseradish extract were 98.5% and 95.4%, respectively. Allyl cyanide, a degradation product of allyl isothiocyanate, was found in the mustard extract and the horseradish extract at the levels of 0.57% and 1.73%, respectively. beta-Phenylethyl cyanide, a possible degradation product of beta-phenylethyl isothiocyanate, and allyl sulfides were found in the horseradish extract, at the levels of 0.13% and 0.46%, respectively. Allylamine, which is another degradation product of allyl isothiocyanate, was determined after acetylation, and was found in the mustard extract and the horseradish extract at the levels of 8 micrograms/g and 67 micrograms/g, respectively.     

浅谈常用食品添加剂的性能特点及应用

介绍了食品添加剂的定义、发展趋势;重点介绍了食品防腐剂、食品乳化剂、增稠剂、食品调味剂以及食用色素等的性能特点及应用;强调食品添加剂的使用安全。     

细菌纤维素纤维对纸张增强作用的研究

介绍了细茵纤维素的合成机理,相关特性以及对纸张的增强机理.研究了细菌纤维素湿膜经机械匀浆处理所得的细菌纤维与植物纤维混合抄片的纸页性能.研究发现:细菌纤维配抄植物纤维,当细菌纤维素的用量为5%时,纸张耐折度提高44.7%,耐破指数提高17.9%,抗张指数提高22.4%,撕裂指数提高16.1%.     

优化陈米糖化液提高细菌纤维素产量的研究

以木醋杆菌（Acetobacter xylinum）为发酵菌种,通过Plackett-Burman试验设计确定了陈米糖化液培养基中酵母膏、KH2PO4、FeSO4、乙醇对木醋杆菌发酵产细菌纤维素具有显著影响,并采用Box-Behnken试验设计对各显著影响因子进行优化,获得最优的陈米糖化液发酵培养基配方为：在陈米糖化液培养基基料中加入酵母膏13.1 g/L、蛋白胨10 g/L、KH2PO4 5.7 g/L、MgSO4 3.1 g/L、FeSO4 0.3 g/L、柠檬酸0.3 g/L、无水乙醇4.0%。在此优化条件下,细菌纤维素的产量为7.08 g/L,是陈米糖化液培养基基料发酵产细菌纤维素（0.38 g/L）的18.6倍,比基础发酵培养基细菌纤维素产量（4.80 g/L）提高了47.5%。     

丙烯酸酯黏合剂对夜光涂层的影响

以丙烯酸酯为黏合剂对织物进行夜光涂层,讨论了黏合剂质量分数及焙烘条件对织物耐磨性能、柔软性及发光性能的影响.结果显示:丙烯酸酯黏合剂质量分数增大,织物的耐磨性能随之提高,但悬垂系数变大,织物明显变硬,同时涂层发光性能变差;焙烘条件的差异对涂层的手感及耐磨性能影响较明显,但对发光性能影响较小.当丙烯酸酯黏合剂为50％,130℃焙烘3 min,涂层各方面性能相对比较理想.     

助剂对漆酶脱色性能的影响

漆酶是一种多酚氧化酶，研究了漆酶LAC—H对活性艳蓝K-3R和直接大红4BS溶液的脱色性能，确定其最佳应用条件，结果表明，在40℃、pH4.0时，漆酶LAC—H有最佳的综合应用性能；通过添加不同物质（如赫类、醇类、表面活性剂等），研究印染行业常见助剂对其脱色能力的影响．研究了递质低分子质量有机物对漆酶脱色的影响，结果发现：在添加了1-经基苯并三唑后，漆酶的脱色能力获得明显提高．     

水性聚氨酯发泡涂层的成膜性能

以甲苯二异氰酸酯（TDI）、聚丙二醇醚（PPG）、聚己二酸丁二醇酯（PBA）和起泡剂为主要原料合成了水性聚氨酯（WPU）,并通过复配稳泡剂、填料、增稠剂、匀泡剂等助剂得到水性发泡WPU浆料。研究了WPU亲水基团含量,以及WPU发泡浆料助剂的种类与用量、起泡条件、发泡比对泡沫稳定性以及成膜物性能的影响,并通过扫描电镜（SEM）表征了成膜物干态泡沫形态。研究表明,WPU亲水基团含量在2%,起泡剂采用0.5%的K 12或1.0%的AES、稳泡剂采用10%硬脂酸钾,浆料黏度在1 000～1 500 mPa·s时,起泡速度快,泡沫稳定性最好。亲水嵌段硅油匀泡剂对泡沫微观形态,以及泡沫成膜物的透气性和低温耐曲挠性能均有重要影响。     

汤料中添加剂对改善非油炸方便面品质的研究

非油炸方便面采用热风对蒸煮后的面块进行脱水干燥,其产品结构细密,复水性差,且复水后面条的口感略涩.通过各种乳化剂、增稠剂在方便面汤料中的使用.对其提高非油炸方便面品质的作用进行了研究,并通过正交试验优选出汤料用品质改良剂复配配方.通过汤料中复配改良剂的使用,能显著缩短面块复水时间,增浓汤汁,改善面条品质.