华中农业大学：《食品化学与分析》精品课程PPT教学课件（讲稿）第6章 维生素与矿物质

第6章维生素与矿物质 制作人:李春

第6章 维生素与矿物质 (Vitamin and Minerals) 制作人： 李春美

6.1 Introduction of vitamins 辅酶或辅酶前体:如烟酸叶酸等 维生素的功能抗氧化剂VEVc 遗传调节因子vAVb 某些特殊功能VA-视觉功能 V血管脆性

6.1 Introduction of Vitamins 辅酶或辅酶前体:如烟酸,叶酸等 维生素的功能 抗氧化剂:VE ,VC 遗传调节因子:VA ,VD 某些特殊功能:VA -视觉功能 VC -血管脆性

Learning objectives-Vitamins Describe the structure and stability of vitamins a Describe the functions of vitamins Identify food and nonfood sources of vitamins Describe the signs and symptoms of vitamin deficiencies and toxicities

Learning Objectives –Vitamins ◼ Describe the structure and stability of vitamins. ◼ Describe the functions of vitamins. ◼ Identify food and nonfood sources of vitamins. ◼ Describe the signs and symptoms of vitamin deficiencies and toxicities

Learning objectives-cont Identify the population group or groups at risk for vitamin and mineral deficiencies Compare your own intake of vitamins to the ideal and identify any potential heal Ith risks associated with your intake

Learning Objectives – cont. ◼ Identify the population group or groups at risk for vitamin and mineral deficiencies. ◼ Compare your own intake of vitamins to the ideal and identify any potential health risks associated with your intake

Classification of vit B1/VB2/VPP TB族{V B5/VB6/ VH Water-soluble vit B11/VB12 Vit A fat-souble vit E

VB1,VB2,VPP B族 VB5,VB6,VH water-soluble Vit VB11,VB12 Vit VC VA fat-souble Vit VD VE VK Classification of Vit

6.2 The Water-solubke vitamin

6.2 The Water-solubke vitamin

Overview of Water-Soluble vitamins a Dissolve in water Generally readily excreted Subject to cooking losses function as a coenzyme Participate in energy metabolism 50-90% of b vitamins are absorbed a Marginal deficiency more common

Overview of Water-Soluble Vitamins ◼ Dissolve in water ◼ Generally readily excreted ◼ Subject to cooking losses ◼ Function as a coenzyme ◼ Participate in energy metabolism ◼ 50-90% of B vitamins are absorbed ◼ Marginal deficiency more common

BVit- VB1(thiamin) + CH2—N CH2—CH20H NH 硫胺素的化学结构 Contains sulfur and nitrogen group Destroyed by alkaline and heat o Coenzyme: Thiamin pyrophosphate(TPp)

一 BVit- VB1 (thiamin) •Contains sulfur and nitrogen group •Destroyed by alkaline and heat •Coenzyme: Thiamin pyrophosphate (TPP)

Stability and Properties ①具有酸碱性质 ②对热非常敏感,在碱性介质中加热易分解. ③能被vB1酶降解,同时,血红蛋白和肌红蛋白可作 为降解的非酶催化剂 ④对光不敏感,在酸性条件下稳定,在碱性及中型 介质中不稳定 ⑤其降解受A影响极大,般在A为050.65范 围降解最快

① 具有酸-碱性质 ② 对热非常敏感,在碱性介质中加热易分解. ③ 能被VB1酶降解,同时,血红蛋白和肌红蛋白可作 为降解的非酶催化剂. ④ 对光不敏感,在酸性条件下稳定,在碱性及中型 介质中不稳定. ⑤ 其降解受AW影响极大,一般在AW为0.5-0.65范 围降解最快. Stability and Properties

谷粉屮的羰基髯 2c ∧级液 的咳系 谷粉、小去粉中 CH 硫胺素和脱羧辅酶降解速率与ρH的关系

硫胺素和脱羧辅酶降解速率与pH的关系