食品中着色剂的检测方法研究进展

着色剂是食品添加剂中的一大类分支,在食品加工和生产中有着广泛的应用。由于食品的基质类型复杂多样,着色剂的种类也非常多、性质差异大,给分析检测工作带来挑战。本文对近年来的食品中着色剂的检测方法进行综述,包括样品前处理和分析检测技术,并根据应用方法和适用的食品基质及检测目标物进行分类总结,为进一步开展食品中着色剂的检测方法的研究工作提供参考。     

食品多元素检测质控图及国际比对结果在 质量控制中的应用

摘要：目的 通过分析本实验室根据标准参考物测定结果绘制的质控图和2013年10月参加食品中多种微量元素含量测定的国际实验室间比对考核结果,探讨质控图及国际比对考核在实验室质量控制中的应用。方法 以Z比分数法评价由国际原子能机构组织的食品中多种微量元素含量测定的国际比对结果,分析食品样品中多种微量元素的测定情况。结果 绝大多数元素的考核结果 <1,结果优秀。结论 质控图和国际比对实验研究是分析实验室质量控制的有效方法,应鼓励有条件的实验室更多地参与国际比对考核,提高检测能力及测定结果的可靠性。     

高效液相色谱—串联质谱法快速测定胶原蛋白粉中呋喃类代谢物

目的简化测定胶原蛋白粉中呋喃类代谢物残留的实验过程,缩短实验的检测时间。方法在GB/T21311-2007的基础上,对其进行方法改进,建立高效液相色谱-串联质谱法(HPLC-MS/MS)测定胶原蛋白粉中呋喃西林(SEM)、呋喃妥因(AHD)、呋喃唑酮(AOZ)、呋喃它酮(AMOZ)等4种呋喃代谢物的快速检测方法。采用55℃衍生化,对衍生品按照离心、调p H值、离心的步骤进行处理,使得调节p H值更容易,同时避免传统试验方法中使用分液漏斗时样品乳化成胶状体而不能达到液液分离的目的的现象。结果实验结果表明,本方法与《GB/T21311-2007动物源性食品中硝基呋喃类药物代谢物残留量检测方法高效液相色谱串联质谱法》相比,结果并无很大的差异,但是大大缩短了实验的检测时间、简化了实验过程。结论本实验方法更加适合大批量样品的试验检测。     

坚果品质检测方法研究进展

坚果含有优质蛋白质、脂肪等丰富的营养物质,深受消费者喜爱。由于富含不饱和脂肪酸及油脂,坚果的品质易受贮藏条件、加工方式及包装方式等外部因素的影响而发生变化,不当的处理会加速其氧化哈败,甚至产生对人体有害的毒素。另一方面,坚果品质受产地、品种、土壤环境及遗传因素等方面的影响表现出不同的外观性状及理化特征。随着科学技术的发展,坚果品质的检测趋向于无损、快速,电子鼻在这方面有着突出的优势,因此电子鼻对坚果品质的无损检测成为研究的新热点。本文从口感、色泽、风味、外观性状等感官检测,营养品质（蛋白质、脂肪等）、油脂品质（酸价、过氧化值等）等理化检测,光谱分析技术（近红外光谱、高光谱等）、电子鼻技术等快速检测方法综述了坚果品质检测方法的研究现状,为坚果品质的监控和检测提供技术参考。     

一种判定RDX热分解机理函数与热安全性的方法

将DSC、TG数据与Malek法相结合研究了RDX的热分解,得到外延起始温度Le0、拐点温度T、峰顶温度Tp、分解终止温度Tf、分解焓变ΔH、表观活化能E、指前因子A、反应级数n、热爆炸临界温度Tb和自加速分解温度TSADT;利用TG热分析得到RDX热分解的起始分解温度T0、质量损失Δm%、最大质量损失速率及对应的温度...     

我国食品检测行业质量管理的现状及其展望

为了应对日益突出的食品安全问题,食品检测机构不断增多,整个行业也在不断地积极加强自身检测体系的建设,以提高检测能力。本文总结了近年来食品检测行业在实验室质量管理方面的经验,阐述了检测机构在综合化的网络服务能力、主流仪器设备的充实,以及实验室资质认可和提高等方面的质量管理现状,着重分析了在样品采集、检测技术开发、专业人才培养,以及信息化建设等方面存在的问题,并提出了相应的改进措施和建议,以推动食品检测行业的发展,更好地为社会服务。     

Does the common criteria paradigm have a future? [security and privacy]

In IEEE Security & Privacy's July/August 2003 issue, the author discussed the then upcoming 4th International Common Criteria Conference, which was held in Stockholm in September. Reviewing the CD of the presentations, however, he is left with the strong impression that, while a good idea when promulgated five years ago (after five years' effort by the six founding nations), the CC enterprise might have run out of gas. The proceedings' record and the author's own sampling of discussions on the CC Forum suggest the management structure and process need considerable revamping if the CC is to have a future.     

Adsorption behavior of multicomponent protein mixtures containing alpha 1-proteinase inhibitor with the anion exchanger, 2-(diethylamino)ethyl-Spherodex

Vegetable milks were developed from fermented and unfermented African yam bean (AYB) flours and their maize blends. AYB was cleaned, dehulled, milled and fermented for 24 hours by the natural microflora present in the legume flour. Maize was fermented for 48 hours. A ratio of 70:30 (protein basis) of AYB: maize was used to formulate the blends. Vegetable milks were prepared from the AYB flours and their maize blends. Standard assay techniques were used to evaluate the milks for proximate, mineral, ascorbate and antinutrient composition. The protein contents of the milks (1.47-2.06 percent) was comparable to soymilk (2.04 percent) and bambara groundnut milk (2.00 percent). The milks contained appreciable quantities of carbohydrate and minerals tested. The milk blends had traces of ascorbate and contained higher phosphorus than the milks from the AYB flours. The fermented milk blend had higher protein, ash and sugar levels and lower phytate and stachyose levels compared to non-fermented blend. Raffinose was reduced to trace levels in the fermented milks. The milks were appetizing. The fermented milk blend was more acceptable than others and was preferred in terms of flavor and color. It had greater advantages over the other vegetable milks evaluated in terms of zinc, phosphorus and stachyose levels.     

Precise and traceable (13)C/(12)C isotope amount ratios by multicollector ICPMS

A new method for the measurement of SI traceable carbon isotope amount ratios using a multicollector inductively coupled mass spectrometer (MC-ICPMS) is reported for the first time. Carbon (13)C/(12)C isotope amount ratios have been measured for four reference materials with carbon isotope amount ratios ranging from 0.010659 (delta(13)C(VPDB) = -46.6 per thousand) to 0.011601 (delta(13)C(VPDB) = +37 per thousand). Internal normalization by measuring boron (11)B/(10)B isotope amount ratios has been used to correct for the effects of instrumental mass bias. Absolute (13)C/(12)C ratios have been measured and corrected for instrumental mass bias and full uncertainty budgets have been calculated using the Kragten approach. Corrected (13)C/(12)C ratios for NIST RM8545 (Lithium Carbonate LSVEC), NIST RM8573 (L-Glutamic Acid USGS40), NIST RM8542 (IAEA-CH6 Sucrose) and NIST RM8574 (L-Glutamic Acid USGS41) differed from reference values by 0.06-0.20%. Excellent linear correlation (R = 0.9997) was obtained between corrected carbon isotope amount ratios and expected carbon isotope amount ratios of the four chosen NIST RMs. The method has proved to be linear within this range (from (13)C/(12)C = 0.010659 to (13)C/(12)C =0.011601), and therefore, it is suitable for the measurement of carbon isotope amount ratios within the natural range of variation of organic carbon compounds, carbonates, elemental carbon, carbon monoxide, and carbon dioxide. In addition, a CO2 gas sample previously characterized in-house by conventional dual inlet isotope ratio mass spectrometry has been analyzed and excellent agreement has been found between the carbon isotope amount ratio value measured by MC-ICPMS and the IRMS measurements. Absolute values for carbon isotope amount ratios traceable to the SI are given for each NIST RM, and the combined uncertainty budget (including instrumental error and each parameter contributing to Russell expression for mass bias correction) has been found to be < 0.1% for the four materials. The advantage of the method versus conventional gas source isotope ratio mass spectrometry measurements is that carbon isotope amount ratios are measured as C(+) instead of CO2(+), and therefore, an oxygen (17)O correction due to the presence of (12)C(17)O(16)O(+) is not required. Organic compounds in solution can be measured without previous derivatization, combustion steps, or both, thus making the process simple. The novel methodology opens new avenues for the measurement of absolute carbon isotope amount ratios in a wide range of samples.