公共營養(yǎng)師培訓(xùn)課件：營養(yǎng)與食品安全學(xué)

1、營養(yǎng)與食品安全學(xué),一、緒論,（一）定義 是（以營養(yǎng)與食品安全專業(yè)知識和技能為手段，以個體或人群為對象）從事營養(yǎng)咨詢、營養(yǎng)測評、營養(yǎng)指導(dǎo)、營養(yǎng)宣教、營養(yǎng)管理以及從事營養(yǎng)教學(xué)與科研工作、營養(yǎng)與食品安全知識傳播的特殊職業(yè)者，是促進(jìn)社會公眾健康工作的專業(yè)人員。 公共營養(yǎng)師是國家勞動部頒布的第4批新職業(yè)之一。是應(yīng)社會、市場的需要而產(chǎn)生的職業(yè)技能人才，指接受專業(yè)知識技能培訓(xùn)，通過國家職業(yè)資格考試認(rèn)證，取得從業(yè)資格（勞部發(fā)199498號文件第六條規(guī)定“勞動部負(fù)責(zé)以技能為主的職業(yè)資格鑒定和證書的核發(fā)與管理”），,（二） 需求,1.社會需求 （1）社會環(huán)境的變化，需要健康品的人數(shù)迅速增加。2006年中國衛(wèi)生部公

2、布了2005年城鄉(xiāng)居民主要死亡原因，慢性病惡性腫瘤、腦血管病和心臟病為城鄉(xiāng)居民前三位死因 日本東京，來去匆匆的“上班族”中，4個人有3個人都挺著“小肚子”；在臺灣，四分之一的學(xué)齡兒童被診斷為“過胖”；中國北京、上海、廣州各大醫(yī)院反映：心臟病、中風(fēng)、糖尿病、腫瘤等發(fā)病率呈大幅度上升趨勢；安徽省中醫(yī)學(xué)院對京、滬、深、港近2萬名25歲以上人士做的調(diào)查顯示，年紀(jì)越輕，體質(zhì)越差；一份長達(dá)10年的健康調(diào)查報告指出，我國中年知識分子的平均壽命僅有5334歲，比72歲的全國人口乎均壽命短了近20歲。,（2）現(xiàn)代醫(yī)學(xué)模式的轉(zhuǎn)變 ：世界衛(wèi)生組織明確提出：下世紀(jì)人類健康的65要靠自己。 合理的營養(yǎng)膳食、適當(dāng)?shù)伢w力活

3、動、 平和的心理心態(tài)、健康的生活方式。 2.職業(yè)需求 （1）醫(yī)院與社區(qū) （2）其它：學(xué)校、餐飲、美容、運(yùn)動、家庭、個人等。,FOODS食物,NUTRITION 營養(yǎng) Nutrients, Functional Factor,HEALTH健康,FOOD HYGIENE 食品衛(wèi)生 Harmful Factors,（It is a science involving natural and social sciences）,緒 論 （PREFACE）,一、 營 養(yǎng) 學(xué) Nutrition,It is a science of foods and the nutrients and other sub

4、stances they contain, and of their actions within the body (including, ingestion, digestion, absorption, metabolism, and excretion).,營養(yǎng)學(xué)是從社會、經(jīng)濟(jì)、文化、心理和食物成分等多方面研究膳食、食物和人體健康關(guān)系及改善措施的科學(xué)。,A broader definition includes the social,economic, cultural, and psychological implications of food and eating.,Delici

5、ous,DEFINITION,（一）定義：,1. CHINA (1) 世界歷史上種植業(yè)、養(yǎng)殖業(yè)最早和最發(fā)達(dá)的國家， 形成了以植物性為主的膳食結(jié)構(gòu) (2) 極為豐富的食品加工技術(shù)和加工食品種類 (3) 極早的食物和營養(yǎng)學(xué)理論：五谷為養(yǎng)、五果為助、 五畜為益、 五菜為充 (4) 系統(tǒng)的食物、營養(yǎng)與健康關(guān)系的認(rèn)識和理論： 藥食兩用、食補(bǔ)與食療 (5) 豐富的食品資源,2. Modern Nutrition (1) 19世紀(jì)：開始對各營養(yǎng)素的認(rèn)識和研究 (2) 20世紀(jì)：主要發(fā)現(xiàn)和研究了微量元素 (3) 近代：與其它科學(xué)相結(jié)合 營養(yǎng)學(xué)分支。,（三）歷史 HISTORY,1. 營養(yǎng)素 nutrients

6、 (1) 熱能與健康 (2) 營養(yǎng)素性質(zhì)與功能：脂肪酸、纖維素、微量營養(yǎng)素、多糖、寡 糖、 酞、氨基酸和核酸等 2. 非營養(yǎng)素 functional factors 酚類(polyphenol)、黃酮(flavone)、甙類(glucoside)等 3. RDA-DRIs 4. 公共營養(yǎng) Community Nutrition 膳食結(jié)構(gòu)（Dietary Pattern）、膳食指南( - Guide)、膳食心理 ( - Psychology)、營養(yǎng)政策(Nutritional Policy)等 5. 營養(yǎng)與慢性病的發(fā)生、發(fā)展和預(yù)防 (Nutrition and Chronic Disease)

7、6. 學(xué)科分類增多 （Branches of Learning）,膳食、營養(yǎng)平衡 (Dietary and Nutritional Balance),（四）進(jìn)展 PROGRESS,（五）核心 CORE,是研究食品中可能存在的有害人體健康的各類因素、危害性及危害機(jī)理和預(yù)防措施、管理辦法及相關(guān)法律、法規(guī)的科學(xué)。 It is a science about the harmful factories in the foods , and their harmfulness, mechanisms the preventive measures, management and the laws and

8、 regulations.,（一） DEFINITION,二、食品衛(wèi)生學(xué) Food Hygiene,（三） HISTORY,1. CHINA (1) 周朝：設(shè)“凌人”管理食品冷藏、防腐 (2)唐律：“ 脯肉有毒曾經(jīng)病人，有余者訴焚之，違者杖 九十；若故與人食，并出賣令人病者徒一年；以故致 死者，絞?！?(3)千金翼方： “食魚面腫煩亂，蘆根水解” (4) 科學(xué)而系統(tǒng)的食品加工與保藏工藝 2. Modern Food Hygiene (1) 細(xì)菌的發(fā)現(xiàn)與消毒方法的應(yīng)用 (2) 有害微生物和相關(guān)毒素的發(fā)現(xiàn) (3) 致癌污染物的發(fā)現(xiàn) (4) 相關(guān)檢測技術(shù)的發(fā)展和應(yīng)用 (5) 法制化：技術(shù)、管理與法律

9、,（四）PROGRESS,(1) 老問題不斷出現(xiàn)：口蹄疫，瘋牛病等 (2) 新的問題不斷發(fā)現(xiàn)：二惡英、雜環(huán)胺、O157、保健食品和 轉(zhuǎn)基因食品的安全性等 (3) 假冒偽劣食品的鑒別與打擊 (4) 環(huán)境污染物和非法使用飼料、食品添加劑等 (5) 法律的不斷完善 (6) 危險性分析、GMP、HACCP等 (7) 經(jīng)濟(jì)全球化，市場、貿(mào)易的國際化與貿(mào)易壁壘。,以科學(xué)為依據(jù)，以法律為準(zhǔn)繩，以提高食品衛(wèi)生質(zhì)量、防止污染和保護(hù)人民身體健康為最終目的。,（五） CORE,第一篇 營養(yǎng)學(xué)PART 1 NUTRITION,1.營養(yǎng)：是指人體攝取、消化吸收、利用食物中營養(yǎng)物質(zhì)和排除廢 物的生物學(xué)過程。 It is

10、a biological process which nutrients and functional compositions in the foods are ingested, digested, absorbed, transported ,utilized and the waste are excreted.,2.營養(yǎng)素： (1)定義：食物中可給人體提供能量、機(jī)體構(gòu)成成分和組織修復(fù)以及有生理調(diào)節(jié)功能的化學(xué)成分。 Chemical substances obtained from food and used in the body to provide energy,structur

11、al materials,and repair of the bodys tissues; Nutrients may also reduce the risk of some diseases.,(2) Classification,protein lipids macronutrients carbohydrate (dietary fiber) nutrients water vitamin micronutrients macroelements minerals microelements,3. 合理營養(yǎng)（Rational Diet） 通過合理的膳食和科學(xué)地烹調(diào)加工，能向機(jī)體提供足夠

12、數(shù)量的熱能和各種營養(yǎng)素，并保證各種營養(yǎng)素之間的數(shù)量平衡，以滿足人體的正常生理需要，并保持人體健康。 Nutrients intakes meet the requirements of the body,5.膳食營養(yǎng)供給量(Recommended Dietary Allowance，RDA) 是對各種人群提出的保證人體營養(yǎng)需要的膳食中應(yīng)含有的熱能和營養(yǎng)素的適宜量。 The average daily amount of a nutrient considered adequate to meet the known nutrient needs of practically all healt

13、hy people; a goal for dietary intake by individuals.,4. 營養(yǎng)生理需要量（Nutritional Requirement） 是指能保持人體健康，達(dá)到應(yīng)有發(fā)育水平和能充分有效地完成各項體力和腦力活動所需要的熱能和各種營養(yǎng)素的必需量。 The lowest continuing intake of energy and nutrients that maintain the specified criterion of adequacy (that will maintain the specific biochemical and physi

14、ological functions of the body).,Chapter 1 Basic Nutrition 第 一 章 營 養(yǎng) 學(xué) 基 礎(chǔ),含量-16%19%. 更新： 動態(tài)平衡，不斷更新，每天約3%，腸和骨髓最快。,Section 1 Protein ( 蛋白質(zhì) ),一、蛋白質(zhì),（一）人體中蛋白質(zhì)：,（二）功能：,1.機(jī)體構(gòu)成成分 2.構(gòu)成各種生理活性物質(zhì)和重要的生理功能 3.提供熱能,（三）The first structure,蛋白質(zhì) (protein),氨基酸 （Amino acid, AA）,非必需AA(nonessential-)：9種 半必需AA（條件必需AA）：2種

15、（semi-,or conditionally-） 必需AA（essentional-）：9種,多肽（poly-）10 AA以上 寡肽（oligo-）410 AA以下 3肽（tri-）3AA 2肽（di-）2AA,肽 (peptide),二、 氨基酸和必需AA( essential amino acid ,EAA),1. 種類：20種 (1) 必需AA（EAA） (2) 非必需氨基酸（NEAA） (3) 半必需氨基酸 ( semi-EAA or conditional EAA) 半胱酸（Cysteine）蛋氨酸（Methionine） 酪氨酸（Tyrosine）苯丙氨酸（Phenylalani

16、ne） 2. 必需氨基酸： 人體不能合成或合成速度不能滿足機(jī)體需要，必需從食物中直接獲得的AA。 Amino acids that the body cannot synthesize in amount sufficient to meet physiological needs and has to obtain them from foods.,表 1-1 人體內(nèi)的氨基酸,*組氨酸為嬰兒必需氨基酸，成人需要量可能較少。 摘自Modern Nutrition in Health and Disease,第9版,第14頁,1999。,(三) 氨基酸模式(AA Pattern)和限制氨基酸 (

17、limiting AA),1. 氨基酸模式 (AA Pattern) ： 蛋白質(zhì)中各種必需氨基酸的構(gòu)成比例。,表1-2 幾種食物和人體蛋白質(zhì)氨基酸模式,數(shù)據(jù)摘自營養(yǎng)與食品衛(wèi)生學(xué)，第3版，第9頁。,2.限制氨基酸 （limiting amino acid）：,與人體蛋白質(zhì)模式比較，食物蛋白質(zhì)中含量相對較 低的必需AA。 The essential amino acid found in the shortest supply relative to the amount needed for protein synthesis in the body. FourAA are mostlikely

18、tobe limiting: Lysine，Methionine，Threonine，Tryptophan .,3.參考蛋白、完全蛋白和蛋白質(zhì)的互補(bǔ)作用,參 考 蛋 白,用于測定食物蛋白質(zhì)質(zhì)量的標(biāo)準(zhǔn)蛋白。 Reference Protein: A standard against which to measure the quality of other proteins.,完 全 蛋 白,必需氨基酸模式與人體蛋白質(zhì)相對一致，能滿足機(jī)體蛋白質(zhì)合成需要的食物蛋白質(zhì)。 Complete Protein: A dietary protein containing all the essential

19、amino acids in relatively the same amounts that human being required. (including animal protein and soy protein ) Incomplete protein,蛋 白 質(zhì) 互 補(bǔ),將兩種或兩種以上的食物蛋白質(zhì)混合事用，使不同食物中必需氨基酸以多補(bǔ)少，從而提高膳食蛋白質(zhì)的營養(yǎng)價值。 Complementary Protein: Two or more proteins whose amino acids assortments complement each other in such a

20、way that the essential amino acids missing from one are supplied by the other.,幾種食物混合后蛋白質(zhì)的生物價,三、蛋白質(zhì)的消化、吸收和代謝,（一）消化和吸收 （digestion and absorption）,Gastric Juice : 1. Acid denaturation 2. Pepsin- not highly specific but preferential attack on bonds adjacent to aromatic AA and leucine. 3.Carboxypeptidas

21、e-terminal aromatic or branch-chained; arginine or lysine; neutral-,dietary Protein,Panc- elastase(彈性蛋白酶)- arometic AA reatic trypsin(胰蛋白酶)- NH2- juice chymotrypsine(糜蛋白酶) - lysine, arginine,dipeptide , tripeptide and free AA,absorbed through the mucosal cells of small intestine peptidase,through th

22、ree active free AA transport systems neutral-,basic- and acidic-.,Liver and other organs,（二） 代謝與氮平衡(metabolism and nitrogen balance),1.代謝,攝入蛋白質(zhì)90克,消 化 道,(30%)肌肉,(50%)器官,體液,其它,機(jī)體蛋白質(zhì),氨基酸池,糞便10g(1.6gN),尿75g(12gN),其它5g(0.8gN),(20%),腸道內(nèi)源性蛋白質(zhì)70g,消化、吸收蛋白質(zhì)150g,圖1-1 蛋白質(zhì)代謝及氮平衡,2.氮平衡（Nitrogen balance）,必要的氮損失（o

23、bligatory nitrogen losses） (2) 氮平衡： BI（UFS）,Positive nitrogen balance,N in N out,N in = N out,Nitrogen equillibrium,Negativenitrogen balance,N in N out,四、食物蛋白質(zhì)營養(yǎng)學(xué)評價,(1)真消化率（true -）,(一)蛋白質(zhì)含量 (content）,(2)表觀消化率（apparent -）:,(二)蛋白質(zhì)消化率(digestibility),(三)蛋白質(zhì)利用率（utilization）,1.Biological value, BV:生物價,The

24、 amount of protein nitrogen that is retained for growth and maintenance,expressed as a percentage of the protein nitrogen that has been digested and absorbed. To determine the actual value of an absorbed protein as it is used by the body.,2.Net Protein Utilization,NPU蛋白質(zhì)凈利用率,The amount of protein ni

25、trogen that is retained from a given amount of protein nitrogen eaten. To determine the amino acid composition and digestibility of a test protein.,3.Protein Efficiency Ratio, PER: 蛋白質(zhì)功效比值,A measure of protein quality assessed by determining how well a given protein supports weight gain in growing r

26、ats. Used to establish the protein quality for infant formulas and baby foods.,4.Amino Acid Score,AAS氨基酸評分,The lowest score is the score of limiting AA which is the AAS of the protein. A method of evaluating protein quality by comparing a test proteins amino acid pattern with that of a reference pro

27、tein; sometimes called chemical scoring.,表1-4 幾種食物和不同人群需要的氨基酸評分模式,摘自WTO Technical Report Series 724,第12頁,1985年。,表1-5 常見幾種食物蛋白質(zhì)質(zhì)量,摘自“營養(yǎng)與食品衛(wèi)生學(xué)”，第3版，第11頁。,5.Protein Digestibility corrected AAS, PDCAAS:（經(jīng)消化率校正的氨基酸評分）,A measure of protein quality assessed bycomparing the amino acid score of a food protei

28、nWith the amino acid requirements of preschool-ageChildren and then correcting for the truedigestibility of the protein; Recommended by the FAO/WHO and used toestablish protein quality of foods for daily valuepercentage on food labels.,表1-6 幾種食物蛋白質(zhì)的PDCAAS,摘自Understanding Nutrition, 第7版，第215頁，1996年。,

29、五、蛋白質(zhì)營養(yǎng)不良（protein-energy malnutrition,PEM）,Kwishiorkor: A Ghanaian word meaning “the evil spirit that infects the first child when the second child is born”. The second child suddenly switched from nutrient dense, protein-rich breast milk to a starchy, protein-poor cereal, soon begins to sicken and

30、die.,Marasmus: A severe deprivation of food over a long time (chronic PEM) and therefore is caused by an inadequate energy and protein intake ( and by inadequate essential fatty acids,vitamins, and minerals as well).,蛋白質(zhì)營養(yǎng)不良,Kwashiorkor,Marasmus,Marasmus,Kwashiorkor,Infancy(less than 2 yr),older inf

31、ants and young children(1-3 yr),Develops slowly;chronic PEM,rapid onset; acute PEM,Severe weight loss,some weight loss,Severe muscle wasting, with fat,Some muscle wasting,with retention of some body fat,Growth:60% weight-for-age,growth:60%-80% weight-for-age,No detectable edema,edema,No fatty liver,

32、enlarged fatty liver,Anxiety焦急, apathy淡漠,apathy, misery痛苦, irritability易怒, sadness,Good appetite possible,loss of appetite,Hair is sparse,thin and dry; Easily pulled out,hair is dry and brittle; easily pull out; changes color; becomes straight,Skin is dry, thin, and easily wrinkles,skin develops les

33、ion,3. 高蛋白質(zhì)膳食過多的危害 （problems of excess protein）,Adult Bone Loss (Osteoporosis骨質(zhì)疏松): Calcium excretion rises as protein intake increases. Recommen-dation of calcium-to-protein is more than 20(mg) to 1(g).,Cancer: population studies suggest a correlation between high intakes of animal protein and some

34、 type cancer ( cancer of colon, breast,kidneys, pancreas, and prostate),Gain Weight: Protein-rich foods are often fat-rich foods. Others.,Heart Disease: Foods rich in animal protein tend tobe rich in saturated fats and cholesterol; homocystei（高半胱氨酸）may be an independent risk factor for heart disease

35、.,六、蛋白質(zhì)供給量和食物來源 （DRIs and Food source）,RNI: 1) 數(shù)量 2）質(zhì)量 (優(yōu)質(zhì)蛋白質(zhì)) Assessment of protein nutrition in human body (1) Serum albumin: 35-50g/L (2) Serum transferritin: 2.2-4g/L (3) Retinol-binding protein: 26-76mg/L (4) Thyroxine-binding-albumin:280-350mg/L 3. Food Source: animal and plant foods. Milk and

36、 Soy been,中國居民膳食蛋白質(zhì)的推薦攝入量: RNI與RDA,RNI與RDA：續(xù)表,Section 2 Lipids ( 脂類 ),固醇類,sterols：,脂類,甘油三脂, triglycerides：,磷脂, phospholipids,99% in body, 95% in food,99% in body, 95% in food,一、脂類的分類 Classification,一、脂類的功能 (function),Structure：1 glycerol 3 fatty acids Function,（一） triglycerides, 甘油三脂(TG),(1) triglyc

37、erides in the body:,A: Storing and providing the body with energy: 1g 9.46kcal (兩個特點(diǎn)） B: The layer of fat beneath the skin helps keep the body warm ( insulating the body) C: Protecting and propping up the organs in the body D: Helping the body use its two other energy nutrients carbohydrate and prot

38、ein ( sparing protein ) E: The very important composition of the body F: Incretion: leptin, TNF-, IL-6, IL-8, adiponectin, resistin, estrogen, Insulin-like growth factor (IGF), angiotensinogen (血 管緊張素), IGF binding protein 3, plasminogen activator inhibitor (PAI, 纖維蛋白溶酶原激活因子抑制物),(2). Triglycerides i

39、n the foods:,A: Providing body with energy and essential fatty acid. B: Improving the color, flavor, taste and shape of foods. C: Because dietary fat causes the stomach to empty more slowly than either carbohydrate or protein, it imparts satiety and satisfaction. D: To supply body with fat-soluble v

40、itamins and aid intestinal absorption of them.,(3). risk of high-fat diet,Heart disease: Food saturated fat (especially 12, 14, 16 carbons) raises blood cholesterol dramatically, which causes heart attack or stroke. Obesity 肥胖: High-fat diet tend to store body fat efficiently. (3) Cancer: Prostate c

41、ancer is a strong association with fat; Breast cancer is a little or no association with diet fat. (4) Risk from trans-fatty acids: They raise LDL and lower HDL.,(二) fatty acids , 脂肪酸 (FA),chain length: long-chain (1014 carbons or more) medium-chain (6 or 8 -) short-chain ( 24 or 26) Saturation（飽和度）

42、: saturated FA (SFA) monounsaturated FA (MUFA) polyunsaturated FA (PUFA) position of double bond: “n” or “” “n-3”: the initial double bond situated between the third and 4th carbon atoms from the methyl end. “n-6”: the initial double bond is between the 6 and 7 isomeric forms 異構(gòu)體: cis 順式 ； trans 反式,

43、(1) Classification,(2). Essential fatty acid, 必需脂肪酸 (EFA),Definition:,Classification:,(1) linoleic acid (亞油酸). C 18:2, n-6 (2)- linolenic acid（ 亞麻酸）. C 18:3, n-3,Fatty acids needed by the body , but not made by it to meet physiological needs.,Synthesize of MUFA in body,linoleic acid (C18:2,n-6) -lin

44、olenic acid (C18:3,n-3) 6去飽和酶 -linolenic acid (C18:3,n-6) 十八碳四烯酸 (C18:4,n-3) 碳鏈延長酶 bi-homotype -linolenic 二十碳四烯酸 (C20:4,n-3) acid (C18:3,n-6) 5去飽和酶 arachidic acid (AA) timnodonic acid (EPA) (C20:4,n-6) (C20:5,n-3) 碳鏈延長酶 二十二碳四烯酸 (C22:4,n-6) clupanodonic acid (C22:5,n-3) 4去飽和酶 二十二碳五烯酸 (C22:5,n-6) doco

45、sahexenoic acid (DHA) (C22:5,n-3),Function of EFA,To maintain the structural parts of cell membranes. (it is a part of phospholipids),Used to synthesize many hormone like substances- eicosanoids（二十烷） : prostaglandins (PG,前列腺 素)，Thromboxane(TXA,凝血惡烷)，leukotrienes (LT, 白三烯 ),hydroxy fatty acids, and l

46、ipoxins(脂素).,(3) Lower blood cholesterol and risk of heart attack or stroke, especially EPA (eicosapentaenoic acid) and DHA (docosahaxaenoic acid).,They modulate cardiovascular, pulmonary, immune, reproductive, and secretory functions in many cells.,Deficiency of EFA,Affect development, production,

47、liver, kidney, nerve, vision, and skin.,(三) 磷脂 (phospholipid),1. Structure：,It consist of a glycerol backbone with one or two attached fatty acids, plus a different structure that includes a phosphate group attached to the other hydroxyl group(s).The most important member is lecithins（卵磷脂）.,2. Funct

48、ion,(1) Important constituents of cell membranes. They thus allow fat-soluble substances, including vitamins and hormones, to pass easily in or out of cells. (3) As emulsifiers （乳化劑）in the body or food manufacturers. (4) To supply body with 9 kcalories per gram. (5) Health function: different points

49、.,(四) 固醇 (Sterols),1. Structure:,A same multiple ring with different side groups attached. Cholesterol is the most important.,2. Function:,Essential to the structure and function of cells, especially the cell membrane (about 90% of total body cholesterol ). Cholesterol is the original material for s

50、ynthesis of many vitally important body compounds such as bile, sex hormones, adrenal hormone, and vitamin D.,3. Harmful effects:,It forms deposits (沉積物) in the artery walls which lead to atherosclerosis (動脈粥樣硬化)- a disease that causes heart attacks and strokes.,二、脂類代謝（metabolism）,mouth,salivary gla

51、nd（唾液腺）-lipase（脂肪酶）: It plays a small role in digestion in adults, but efficiently digests the short- and medium-chain fatty acids of milk in infants.,Stomach,Stomachs churning 攪拌 action mixes fat with water and acid . A gastric lipase hydrolyzes a very small amount of fat.,Small intestine,emulsific

52、ation of fat by bile,Pancreatic lipase Intestinal lipase,bile,trapped by dietary fibers and carried out of the body with the feces,Reabsorbed into the blood liver Gallbladder(膽囊),Monoglyceride, fatty acids and glycerol,Long-chain fatty acids Monoglycerides,Glycerol, short- and medium-chain Fatty aci

53、ds absorbed directly into blood,Merge （結(jié)合）into micelles (微膠粒),Merge （結(jié)合）into micelles (微膠粒),Easily diffuse (擴(kuò)散) into the intestinal cells and reassembled (重新合成) into new triglycerides.,With cholesterol and phospholipids,Chylomicrons within the intestinal cells,Absorbed into lymph,then into blood Cel

54、ls all over the body remove lipids from the chylomicrons（乳糜微粒） as they pass by, and make them smaller and smaller.,protein,Liver cells collect the chylomicron remnants（殘體）, and pack them with lipids , cholesterol and proteins as VLDL which will travel through the body in the blood.,HDL made in the l

55、iver carry cholesterols and phospholipids from the cells back to the liver.,They lose triglycerides and gather cholesterol from Other lipoproteins circulating through the bloodstream And become LDL,Metabolism of cholesterol,三、 Food source and RDA 脂類的食物來源及供給量,1. Food source:,1). Animal fat: plenty of

56、 SFA,2). Vegetable oil: plenty of MUFA,Linoleic Acid (n-6),leafy vegetables, seeds, nuts, grains, vegetable oil(corn, safflower 紅花, soybean, cottonseed, sesame芝麻, sunflower),Arachidonic Acid (n-6),meats, can be synthesized from linoleic acid,linolenic acid（n-3）,fats and oil ( soybean, walnut胡桃, whea

57、t germ),EPA and DHA (n-3),Human milk, shellfish and fish (mackerel 鮐魚, tuna 金槍魚, salmon大麻哈魚, sturgeon鱘魚, herring鯡魚, trout鱒魚, sardines沙丁魚), can be made from linolenic acid.,2. DRIs: basic principle,percentage of total dietary energy ：20%-30% SFA / total dietary energy 10% n-6 / total dietary energy 3

58、%, n-6n-341 Cholesterol 300mg/d,3. Substitute of fat,蔗糖聚酯 sucrose polyester, Olestra 燕麥素 Ostrim,AIs of dietary fat (percentage of total dietary energy ),注1：SFA為飽和脂肪酸；MUFA為單不飽和脂肪酸；PUFA為多不飽和脂肪酸 注2：n-6/n-3表示n-6系列不飽和脂肪酸與n-3系列不飽和脂肪酸的比例,Section 3. carbohydrate 碳水化合物,一、分類與食物來源 Classification and food source,單糖(monosaccharide) 雙糖(disaccharide) 寡糖(oligosaccharide) 多糖（polysaccharide）,（一）單糖 (monosaccharide),1.Glucose: