文档介绍：Chapter 2. Nutritional Value of Foods 各类食品的营养价值
How to choose?
What do you eat and why?
So many foods
Delicious ?
Allaying hunger ?
Nutritional value ?
食品的营养价值(nutritional value)
是指某种食品所含营养素和热能满足人体需要的程度。取决于营养素的种类、数量、相互比例及消化吸收率。
Nutrition value is degree or percentage of nutrients and energy in food that can meet human requirement. It rests with the kinds, quantity, proportion and absorption rate of nutrients.
Assessment of food nutritional value:
The kind and quantity of nutrients :analysis, position
(化学分析、仪器分析、食物成分表)
The quality of Nutrients: the rate of absorption and availability
(吸收利用率: BV,NPU,PER)
Change during cooking and processing: loss
营养质量指数(index of nutrition quality, INQ)
某营养素密度某营养素含量/该营养素供给量
INQ=——————=————————————
热能密度所产生热能/热能供给量标准
食物的营养价值(成年男子轻体力劳动)
energy
(kJ)
protein
(g)
(µgRE)
(mg)
(mg)
RNI(A,M,L)
10878
800
100g egg
653
194
INQ
100g rice
1456
----
INQ
----
100g soybean
1502
INQ
Classification of food
Origin and Character:
⑴ animal food
⑵ plant food
⑶ food produces
nutritional character:
(1) cereal grain
(2) legumes and its produces
(3) vegetables and fruits
(4) meat, poultry and fish
(5) milk and its produces
(6) egg and its produces
CEREAL GRAINS
Cereal grains are seeds of the grass family.
Wheat , rice, corn, kaoliang are the most important cereals used for human food.
1、结构与营养成分 (structure position)
bran 纤维素和半纤维素
5% 蛋白质、脂肪、B族维生素
aleurone layer 蛋白质、磷、B族维生素
8%
endosperm 淀粉,蛋白质
83%
germ 蛋白质、脂肪、可
2-3% 溶性糖和B族维生素
(nutritional value )
They provide us with a majority of our food calories and about half of protein.
Protein
~15% EAA不平衡
BV偏低
Carbohydrates 淀粉 90%
>70% 单糖 10%
Fat 不饱和脂肪酸
1~4% lay in germ and bran mainly
Mineral (P,Ca),
~3% lay in bran and aleurone layer
Vitamins B vitamins
(thiamin,ribo