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1、FOOD ANALYSISSong-LihuaInformation about the CourseCourse DescriptionI .Introduction to food analysis technologyII. Sampling, preparation and pretreatmentIII. Basic physical analysis methodsIV. Basic instrumental analysis technology (AAS, GC, HPLC)V. Analysis methods of water, carbohydrates, lipids,

2、 amino acids and proteins, vitamins, elements, part of food additives,etc GRADINGClass:10%(attendance and discussion)Homework:20%Final Exam:70%Aim and Student Learning es of this partTo provide an introduction to the significance of the course and the related methods used in food analysisThe student

3、s should know the application and methods of food analysis technology; familiar with the main content of food analysis technologyIntroductionFour things in life: Food is the first thing for people “FoodClothingHousingtransportationFoodie?IntroductionEight major cuisines of ChinaIntroductionSafety qu

4、alitySensory qualityNutrition qualityIntroductionCharacteristics of foods: chemical compositionphysical propertiessuch as viscosity, creaminess, and texture sensory propertiesQuestion:Do you know the goal of Food Science?To research foods to better understand their composition and properties so we c

5、an make them: Taste BetterLast LongerMore ConvenientSafer To EatMore NutritiousAvailableLess ExpensiveGoals of F.S.Determination of food composition and characteristics,Monitor food composition and to ensure the quality and safety of the food supply from farm to tableAnalytical Technique Main Conten

6、ts of the Food analysis technology Food categories:Main components: cereal, (soy)bean products, meat and seafood, poultry and egg, milk and dairy products, beverage and all types of seasonings Composition of food Natural Non-Natural water、minerals contaminated stuff protein、carbohydrate food additiv

7、es lipid、vitamin、pigment(curcumine) aromatic substances、toxinCanada,2003European Union,2008China/Hong Kong,2008India, 2008United States, 1995A UK nutrition information label, for low-fat yoghurt. A key difference from US labelling is that fibre is not considered a type of carbohydrateNutrition Label

8、/Nutrition information panelNutrition Label/Nutrition information panelAustralia and New ZealandNUTRITION INFORMATIONServings per package: xServing size: y g (or mL etc.)Quantity per ServingQuantity per 100 g (or 100 mL etc.)Energyn1 kJ (n1 Cal)m1 kJ (m1 Cal)Proteinn2 gn2 gFat, totaln3 gn3 g - satur

9、atedn4 gn4 gCarbohydraten5 gn5 g - sugarsn6 gn6 gSodiumn7 mgn7 mgWhat is the significance of Nutrition LabelNutrition composition analysisUpdating of Food Composition Table(Calculate the Nutrients content,Recipes preparation for diabetes patient)Author: Chinas Centers for Disease Control and Prevent

10、ion (China CDC) Other authorities databaseUSDA National Nutrient Database for Standard Reference- United States Department of Agriculture,USDAMcCance and Widdowsons the Composition of Foods- The British Food Standards Agency and Food Research InstitutePart of Food Composition TableContents of the ta

11、bleTable 1 General nutrient components in foods Table 2 Amino Acid Content in foods Table 3 Fatty Acid Fraction Table 4 Iodine content Table 5 Soybean isoflavone content in foodsSupplement : phytosterolAppendix: Glycemic index (GI)Tip: GI-Indicating the effects of various foods on blood sugar. Fast-

12、releasing foods that raise blood sugar levels quickly are high on the index, while slow-releasing foods, at the bottom of the index, give a slow but sustained release of sugar Improving condition of processing, storage and transportation (eg. )The processing of Functional Vegetable PowderExploration

13、 and exploitation of new food source (edible wild herbs or fruits,can you give me some e.g.?)Nutrition Composition AnalysisEdible CactusFreeze DryingCrystal sublimation Spray Drying Steam evaporationFood Safety Issue Safe food means that there will be no danger from pathogenic microorganisms, natura

14、lly occurring toxins and other potentially harmful chemicals which may be deliberately added to foods.hogwash oilSep. 04. 201423 million tons/yearDinner tableToxicity of gutter oil:trans fatty-acidsbenzopyrenelarge quantities of bacteriaaflatoxinother dirty elements that accumulate in sewageheavy me

15、tal contamination ( e.g. lead, arsenic)2010- green bean events HainanFood Quality Monitoring CenterThree kinds of forbidden pesticides Agricultural Technical Extension Station2008-melamine Kidney stoneKidney failureMalnutrition Syndrom2004Big-Head Baby incident in Fuyang Anhui Province Food safety i

16、ssue-AntibioticHigh density breedingContamination of waterLack of supervisionHarmful effects of misuse/overuse antibiotic1. Antibiotic resistance/ drug resistance2. Allergic reaction 3. Destroy the balance of intestinal floraMandarin FishFood AdditivesFood AdditivesFood AdditivesDo you know the food

17、 additives used in processed food?What is the purpose of food additives used in processed food? acidity regulator antitackiness agent antioxidant bleacher colorant color fixative defoamer emulsifier flavoring agent nutrient supplements preservative swelling agent sweetener spice stabilizer thickenin

18、g agent zymin 27 categories2000 kinds of food additivesPreservativesOthers: thickener, essence, emulsifier, Food and water conservation agent Except preservatives, there are other food additives used in moon cake: acidity regulator, swelling agentBulking Agent-used in bread or cookiePigment/coloring

19、e.g.Natural: Curcumin Artificial :Prussian Blue Hyperactivity diseaseCarcinogenAsthmaRhinitis?Food additives in ice creamIf you love her, take her to Haagen-Dazs 2001, band of GM(General Mill)4 natural ingredients: skim milk, fresh butter, fresh yolk, and sugarFood AdditiveWhat about your opinion on

20、 this?No Food Additives No Food IndustryFood additive issueExcessive use Abuse (gelatin)Some toxicity unknown E.g. saccharine bladder cancer? Mixture of many different food additivesFood safety issue in the worldTaiWan bottled beverages and dairy products: Industrial plasticizer DEHP Main Contents o

21、f the Food analysis technologyNutrition constituentWater, ash, fat, protein, carbonhydrate, protein and amino acid, vitamineFood safetyAntibiotic (fresh water fish , etc)Adulterated food (honey, etc)/ AuthenticityFreshness ( fresh food: meat, milk, fish, even water )Package (eg. Nestle)Food additive

22、Pesticide residuePathogenic bacteria and toxinHeavy metal residuesEdible quality (colour, fragrance, taste)-Food sensory evaluationRole of Food Analysis Technology in Food IndustryFood analysistechnologySafetyNutritionEdible qualityProduct developmentSignificance of the food analysisSocial benefitsN

23、utritional LabelingAuthenticity Food Safety Quality control Research and Development Food EnterprisesGovernment FDAWho analyzes foods?Why do they analyze foods?quality managementResearch instituteIMPORTANCE OF FOOD ANALYSISIt helps to determine or assess the nutritional content of food stuffs.Helps

24、to protect the consumers health. Detecting spoilage which may be chemical or biological such as rancidity, browning etc.Food analysis helps in standardization of products on the marketHelps in detecting naturally occurring components and their quantity in foodsIn quality control, analytical methods

25、are used on the critical points or at the end to asses if the product meets national or international standards.DefinitionFood analysis refers to the assessment of food composition using chemical biological or physical methods. It is a tool used to ascertain the quality of food.There are two major t

26、ypes of analysis conducted on food. These include:WHAT Qualitative analysisHOW MUCH Quantitative analysisFood Analytical Methods1、Sensory analysis2、Chemical and physical analysisTitrimetric analysis, Gravimetric analysis Polarimetry and RefractometryAutomatic kieldahl apparatus 3、Instrumental analys

27、is (trace and rapid) Emission spectroscopy Absorption spectroscopy4、Other methods (e.g. enzymology, immunology )UV-Vis (Absorption) Spectrometry Luminescence/fluorescence Spectroscopy Infrared Spectrometry Atomic Absorption SpectrometryGas ChromatographyLiquid ChromatographyElectrophoresisMass Spect

28、rometryInstrumental AnalysisCurrent Status and future trends Current statusTime consuming (especially pretreatment/preparation)E.g. Organic damage method-Microwave assisted digestion Kjeldahl nitrogen determination method Further lower detection limit , high sensitivityFuture trendsRapid detection (

29、e.g. Fresh milk used in ice cream)Instrumental and automatic analysison line quality control and nondestructive analysisBio-detector/sensor Did you ever measure a smell? Can you tell whether one smell is just twice strong as another? Can you measure the difference between one kind of smell and anoth

30、er? It is very obvious that we have very many different kinds of smells, all the way from the odour of violets and roses up to asafetida. But until you can measure their likeness and differences, you can have no science of odour. If you are ambitious to find a new science, measure a smell. Alexander

31、 Graham Bell, 1914 Scientist Alexander Graham Bell popularized the notion that it was difficult to measure a smell, and in 1914 said the following:Interesting topic-Eg. E-nosehuman olfaction E-noseApplication: Identification (finger print)ComparisonQuantification Data storage and retrieval Interesti

32、ng topic-Biosensor/E-Sensing Technologies Composition of the device:sample delivery systema detection system(sensor set)a computing system In quality control laboratories for at line quality control Possible and future applications in the fields of health and security In process and production depar

33、tments Possible and future applications in the field of crime prevention and security In environmental monitoring Possible applications in the futureApplication of infrared technique in food analysisApplication of electronic nose in food analysis Other type of biosenser in food analysis mended Readi

34、ng MaterialsGeneral analytical procedureSelection of Method Standard MethodSamplingDetection Statistical analysisHow to select appropriate analytical techniquesAbout Standard MethodsClassification of Authority Methods International standard(arbitration method )National standardISOInternational Stand

35、ardization OrganizationCACCodex Alimentarius Commission CCPRCodex Committee On Pesticide ResiduesAOACAssociation of Official Analytical Chemists E.g.National Standards ChinaGB USAANS BritainBS GermanyDIN FranceNF ItalyUNI SpainUNEGB: GB5009.1GB5009.702003GB 49272001GB 49282001GB 181862000GB 18187200

36、0GB 5009.551996 2007, 600 items were revisedtechnical barrierE.G. 1. Chloramphenicol in aquatic products exported to the EU exceed the limitation standard (2000 times higher)E.G. 2. Detection of trimethylamineAccurate (error and bias, repeatability/reproducibility )Several conception: Precision; Acc

37、uracyAccuracy indicates proximity of measurement results to the true value, precision to the repeatability or reproducibility of the measurementError sources: random errors ? systematic errors? Selecting an Appropriate Technique Selecting an Appropriate Technique Accuracy: A measure of how close one

38、 can actually measure the true value of the parameter being measured (degree of closeness of measurements of a quantity to that quantitys actual (true) value)Precision/Repeatability: A measure of the ability to reproduce an answer between determinations performed by the same operator (or group of sc

39、ientists) using the same equipment and experimental approach during a short time period.Reproducibility/Ruggedness: A measure of the ability to reproduce an answer by operator using the same experimental approach but in different laboratories using different equipment over longer time periods. Sensi

40、tivity: Magnitude of change of a measuring device (instrument) with changes in compound concentration. Detection limit: A measure of the lowest concentration of a component that can be detected by a given procedure.Discussion topic :How to describe precision and accuracy?Precision:RSD (relative stan

41、dard deviation)CV (coefficient of variation )Accuracy:Relative errorRecovery rateThe accuracy and precision of a measurement process is usually established by repeatedly measuring some traceable reference standardn = total population of samplesCV5% acceptableSafe (e.g. potassium cyanide, isotope )Fast SimpleCheapDestructive/Nondestructive:On-line/Off-lineOfficial ApprovalNature of Food MatrixSelecting an Appropriate Technique Ma

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