topic11 eggs Flashcards
free run vs free range
free fun: They are not confined to cages, but they may not have access to the outdoors. Instead, they have space to roam and exhibit natural behaviors within a sheltered environment.它们不会被关在笼子里，但它们可能无法进入户外。相反，他们有空间漫游，在一个庇护的环境中表现出自然的行为
Free range:While they may spend part of their time indoors, they are granted outdoor access, and the idea is to provide a more natural environment for the chickens to express their natural behaviors.它们可能会在室内度过一部分时间，但它们被允许到室外活动，这样做的目的是为鸡提供一个更自然的环境来表达它们的自然行为。
nutrition value of eggs
1.Eggs have highest PER (protein efficiency ratio: measure of protein quality)
2.13 essential vitamins and minerals E.gRiboflavin, selenium
3.Fat (yolk)
in yolk: iron, vitamin A, cholesterol, choline, lutein叶黄素, zeaxanthin玉米黄质
Egg formation
26 hours —> 1 egg
brown or white egg?
same in nutritional value
egg composition for different nutritional values
75% water
12% protein
10% fat
1% carbohydrate
1% minerals
egg weight
~57g with shell, ~50g without shell, 2/3 albumen, 1/3 yolk
different proteins in albumen
- ovalbumin
2.ovomucin
3.lysozyme
pH of albumen
fresh pH of 7-8.5, increase due to loss of CO2 during storage
characters of ovalbumin
- contributes to foaming
2.denatured by heat
characteristics of ovomucin
viscous(粘稠的) gel properties
2. contributes to foam stability
properties of lysoenzyme
Antimicrobial enzyme; part of the innate immune system
Thermally stable (up to 72°C)
Large pH range of 6-9
protein in egg yolk
lipoproteins: emulsifying proterties
lipids in egg
Triglycerides
Phospholipids
Cholesterol
1/3rd of the weight of the yolk
Taste
Question: eggs and heart health?
omega-3 fatty acids lower risk of CVD, normal people do not need to limit egg yolk consumption
what is vitelline
yolk
