食品专业英语28 Food Analysis Technology电子课件.ppt

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1、食品专业英语28 Food Analysis Technology 电子课件Food Analysis Technology 食品专业英语Unit 28一.词汇讲解二.课文阅读三.课后小结 食品专业英语p spectroscopy 光谱学p components 组件p derivatization 衍生化p phenolic 酚类p flavonoid 类黄酮p anthocyanin 花青素p carotenoid 类胡萝卜素p fluorimetry 荧光测定法p emission 发射p excitation 激发p infrared spectroscopy 红外光谱法p quali

2、tative 定性一.词汇讲解p atomic absorption 原子吸收p trace 痕量p titration 滴定法p raman 拉曼p vibrational 振动p complementary 互补p bonding 成键p scattering 散射p fragments 片段p electrostatic 静电p hyphenated 连接p nuclear 原子核p magnetic 有磁性的p resonance 共振p resonance 共振p fluorescence 荧光p crystalline 水晶般的p amorphous 无定形的p phytochem

3、icals 植物化学物质p volatile 挥发性p homogenization 均质p headspace 顶部空间p fourier 傅里叶p automatable 自动化的一.词汇讲解二.课文阅读 In recent years,consumers have become increasingly concerned about the safety and quality of their food supply.To ensure that food supplies meet the highest standards of safety and nutritional qu

4、ality,robust and state-of-the-art analytical methods are essential for all food products.The rapid growth of novel raw materials and ingredients,and new processes in the food industry has also brought new challenges to food scientists.1 近年来，消费者越来越关注食品的质量与安全。为确保生产的食品符合最高安全和质量标准，稳定且先进的分析方法对所有食品都至关重要。新

5、食品原料和活性成分的快速增加以及新工艺都给食品科学家带来了新的挑战。译文二.课文阅读 The progresses in food science and technology have driven analytical methods toward those that heavily rely on instrumentation and biochemistry,which provide higher sensitivity and accuracy.This article attempts to cover the recently developed technologies

6、in food analysis.2 食品科技的进步推动了那些严重依赖仪器和生物化学的分析方法，这些方法具有更高的灵敏度和准确性。本文试图涵盖最近开发的食品分析技术。译文二.课文阅读1.Spectroscopy1.SpectroscopyFood Food Analysis Analysis Technology Technology 2.Chromatography3.Mass spectrometry4.Nuclear magnetic resonance5.X-ray method 1.Spectroscopy Ultraviolet and visible spectroscopy U

7、ltraviolet and visible spectroscopy(UVvis)is one of the most commonly encountered techniques in food analysis.The wavelength of UV light ranges from 200 to 350 nm,and that of Vis light ranges from 350 to 700 nm in the spectrum.Analyses of total phenolic,total flavonoid,total anthocyanin,and total ca

8、rotenoid contents in food are good examples.3 紫外和可见光谱法 紫外和可见光谱法（UV-vis）是食品分析中最常见的技术之一。紫外光的波长范围为200 至350nm，可见光的波长范围为350 至700nm。对食物中总酚、总黄酮、总花青素和总类胡萝卜素含量的分析就是很好的例子。译文 Infrared spectroscopy IR spectroscopy refers to the measurement of the absorption of different frequencies of IR radiation by any food c

9、omponent in a solid,liquid,or gaseous state.IR spectroscopy can be categorized into near-IR of which the wavelength is 0.82.5 mm;mid-IR of which the wavelength is 2.515 mm;and far-IR of which the wavelength is 15100 mm.The near-and mid-IR regions of the spectrum are both useful for qualitative and q

10、uantitative analysis of foods.4 红外光谱法 红外光谱法是指通过测定固态、液态或气态的任何食物成分吸收红外光区的电磁辐射的分析方法。红外光谱可以分为近红外（波长为0.8-2.5 毫米）；中红外（波长为2.5-15 毫米）；远红外（波长为15-100 毫米）。光谱的近红外和中红外区域都可用于食品的定性和定量分析。译文 For food industry,the most important is attenuated total reflectance in conjunction with Fourier transform IR(FTIR)technology.

11、It is available for the analyses of fats and oils,meats,butter,milk,even sweetened condensed milk,and juices.FTIR(Figure 6.2)is convenient,rapid and automatable,and has dramatically simplied sample handling.5 对于食品工业，最重要的是将衰减全反射与傅里叶变换红外（FTIR）技术相结合。它可用于分析脂肪和油、肉类、黄油、牛奶甚至加糖炼乳和果汁。FTIR（图6.2）方便，快速且可自动化，并且明

12、显简化了样品处理。译文FTIR spectroscopy Nicolet iS10.Atomic absorption and emission spectroscopy Atomic spectroscopy is widely used for accurately measuring the trace amounts of minerals in food.Although traditional chemistry titration methods for mineral analysis,such as iron,chloride,calcium,and phosphorus,r

13、emain in use today,it has been largely replaced by atomic spectroscopy.In theory,virtually all of the elements in food can be measured by atomic spectroscopy.原子吸收和发射光谱法 原子光谱法广泛用于精确测量食品中痕量矿物元素。虽然传统的矿物质元素分析法-滴定法，如对铁、氯、钙和磷元素测定，如今仍在使用，但它已经在很大程度上被原子光谱法所取代。理论上，食物中的几乎所有元素都可以通过原子光谱法测量。译文6 There are two type

14、s of atomic spectroscopy,namely atomic absorption spectroscopy(AAS)and atomic emission spectroscopy(AES).AAS is based on the absorption of ultraviolet or visible radiation by free atoms in the gaseous state.Figure 6.3 is the photograph of AAS.原子光谱法有两种类型，即原子吸收光谱法（AAS）和原子发射光谱法（AES）。AAS 基于气态自由原子对特定紫外或可

15、见辐射的吸收。图6.3 是AAS 的照片。译文7 Figure 6.3 Atomic absorption spectroscopy spectra 240FS AA.2.Chromatography High performance liquid chromatography Chromatography has found its use in nearly all areas of food analysis.High-or ultrahigh performance liquid chromatography Compared with conventional column chro

16、matography,HPLC is much faster.It is a convenient and widely used technology for sugar content,pesticide residues,amino acids,toxins,organic acids,lipids,vitamins,and various phytochemicals in foods.色谱法 高效液相色谱法 色谱法几乎已应用于所有食品分析领域中。高效或超高效液相色谱与传统柱色谱相比，液相色谱更快。它是一种方便且广泛使用的技术，用于食品中的糖含量、农药残留、氨基酸、毒素、有机酸、脂类、

17、维生素和各种植物化学物质分析。译文8 Gas chromatography GC is a separation method used to analyze thermally stable volatile substances.For example,GC has been used for the determination of fatty acids,triglycerides,avor compounds,and many other food components,as well as pesticides,aroma compounds,and other volatile

18、contaminants.气相色谱法 GC 是一种用于分析易挥发性物质的分离方法。例如，GC已用于测定脂肪酸、甘油三酯、风味物质和其他许多食品成分，以及农药、芳香化合物和其他挥发性污染物。译文9 Sample preparation is a critical step in GC analysis.It generally involves grinding,homogenization,and isolation of analytes from food samples,which may be achieved by headspace analysis,distillation,pr

19、eparative chromatography,or solvent extraction.样品制备是GC 分析中的关键步骤。它通常涉及从食品样品中研磨，均质和分离分析物，这可以通过顶空分析、蒸馏、制备色谱或溶剂萃取来实现。译文10 3.Mass spectrometry Mass spectrometry(MS),different from the above discussed spectroscopic techniques,is based on the detection of charged molecules or fragments of a molecule.The ge

20、nerated ions are separated in the electrostatic field and then nally detected according to their mass-to-charge ratio(m/z).The results from ion generation,separation,fragmentation,and detection are manifested as a mass spectrum that can be interpreted to yield molecular weight or structural informat

21、ion of a compound.质谱 质谱（MS）与上述光谱技术不同，它是基于带电分子或分子片段的检测。产生的离子在静电场中分离，然后根据它们的质荷比（m/z）最终检测。离子产生、分离、碎裂和检测的图谱可以解释为产生化合物的分子量或结构信息的质谱。译文11 MS is now interfaced with GC and HPLC,and the hyphenated analytical methods are powerful tools and now widely used for analyzing various food components in a mixture.MS现在与GC和HPLC 联合使用，气相-质谱和液相-质谱联用是强大的分析工具，现在广泛用于分析混合物中的各种食品成分。译文12Belive yourself!You will succeed!