Yolk and albumen are the two parts of an egg. While yolk is the inner yellowish part of an egg, albumen is the external white part. An egg's nutritional value is due to the various proteins, minerals and vitamins that is present in the egg white part or the albumen. Albumen is made up of 99% water and constitutes nearly two-third of the entire egg's weight. The yolk of an egg also consists of proteins and minerals, however, it is found to have higher cholesterol levels.
Chicken eggs are a readily available with low price; why not throw a few on the breakfast table? Try incorporating eggs into sandwiches, salads, soups and snacks for a more balanced life and higher energy levels; because, Chicken eggs are a power-packed food with many health benefits. The egg is more than nature's most perfect food. The egg is also nature's most perfectly created most nutritious food items in our diet.
Eggs are a great source of protein. Numerous vitamins, including vitamin A and D, potassium and many B vitamins like folic acid, choline and biotin, are also packed into this oval-shaped staple. In fact, very few foods share the same diverse nutrient makeup available in a single egg. Many of these are specifically needed for the health of the nerves and the brain. Like the B vitamins, choline is a coenzyme needed for metabolism. Choline exists in all living cells, but is probably best known as a major part of lecithin - the emulsifier that keeps fats and cholesterol from clumping together in the blood. Through the years, all fats have become public enemies, often blamed for an increased risk of heart disease. Eggs fell out of favor and people gravitated toward egg whites as a substitute. In truth, the yolk is where many of the vitamins and nutrients are found. Eggs also contain carbohydrates and good source of essential minerals such as calcium, iron, phosphorus, zinc and iodine. How can eggs contain anything not wholesome and beneficial to humans?
Eggs have been condemned over the years, this nutrition powerhouse has acquired a bad reputation from reports they contribute to raised cholesterol. Their high lecithin and methionine content ignored, yet lecithin is an essential part of our diet. It emulsifies fat, breaking it down to smaller fat droplets. This action speeds up and improves the digestion of fats by enzymes because the surface area is increased. Lecithin aids liver function, keeps the arterial lining free from cholesterol and prevents gall and kidney stones from forming. Methionine is also essential in the formation of nucleic acid of the genetic material of every cell. It's a powerful antioxidant, assists in Gallbladder function and detoxifies heavy metals and excess histamine levels from the body. Like other pieces of information associated with cholesterol, avoiding eggs is off the mark.
Myths of Cholesterol in eggs
The topic of cholesterol has become very confusing. Dietary advice on the subject is often so far off that consumers actually hurt their health by trying to avoid cholesterol. The body needs to achieve a balance when it comes to cholesterol consumption. Fat from healthy sources is vital to the body, while fat from poor choices, such as margarine or foods fried in vegetable oil, are very dangerous. Eggs remain a beneficial source of healthy fat. Many nutrients, such as vitamin A, are better absorbed with fat, making eggs a very good source of vitamin A. Research has documented that eggs do not appear to promote heart disease risk.
Research also shows that humans do not increase blood cholesterol levels by eating cholesterol. Rather, we increase cholesterol by eating refined processed flour, sugars and fats. Based on these findings, we should eat eggs to help reduce cholesterol because of the lecithin content and avoid the processed and dead foods that are the real cause of cholesterol.
We all need protein, but it's not only the amount of protein that counts, it's the variety or number of different amino acids that can be found in the proteins. There are 20 amino acids with eight of them considered essential in the diet because our bodies cannot make them. Eggs are one of the few foods containing all the essential amino acids. With these, our bodies can make whatever non-essential proteins they need.
Diabetics (people suffering from the medical condition of Diabetes mellitus) may be one of the only groups that should avoid averaging more than one egg a day, as they might show some increases in cholesterol with higher egg consumption. But even in diabetics, eggs can be very helpful.
But every egg is not created equal. The contents in an egg depend on what was in the chicken that laid it! It's best to buy any source of protein from an environment that is as natural as possible, meaning the animal was able to feed on foods that its body could tolerate, in conditions that were not overly stressful. For egg-producing chickens, this environment is often called "cage-free." This means the chicken was allowed to roam, picking what it wanted to eat. Research has shown that cage-free hens have produced eggs higher in various vitamins. Chickens packaged tightly in cages undergo stress, lowering their immune systems and raising their likelihood of infection. Frequent infections are a common problem for animals raised in cramped quarters. Many times, chickens are given regular antibiotics to help keep down infection rates. These antibiotics may lead to stronger, more resistant bacteria in the feces of the chicken and even in that of the farmer who raises them. This presents two big potential problems for the consumer: (1) antibiotics like sulfa in the chicken that could aggravate drug allergies, and (2) super resistant bugs. Cage-free eggs actually show greater resistance to bugs like salmonella. When purchasing eggs, choose those that were grown in a cage-free environment, or better yet, purchase eggs directly from a farmer who focuses on growing eggs in a healthy environment. Eggs that say "organic" or "omega-3" have the right idea, but will still not be as good as cage-free.
You may find it difficult or costly to obtain farm fresh eggs, but when you compare the nutritional value of eggs to any other whole food, healthy eggs are your best buy. You pay now or pay later!
The nutritional content of eggs can vary considerably with the source and time spent in storage. Nutritional authors advise us to avoid the mass-produced industrial standard eggs from caged hens. These may contain unwanted antibiotics and growth stimulants and viral infections as well as chemical contaminants from their food. Find and eat only farm fresh free-range chicken eggs. But that is not always possible.
Like nearly all foods, eggs lose some nutritional value when cooked. Regular egg eaters should choose not to scramble their eggs every time. When the yolk of the egg is broken and exposed to high heat, the proteins and fat of the eggs are damaged. In this case, the fat does become unhealthy. Eating scrambled eggs occasionally is not a major problem; just don't make it your routine. Poached or soft-boiled eggs are best. Avoid hard-boiled eggs where the blue-green sulphur has separated from the yolk.
How to test if an egg is fresh or not?
High quality eggs have hard shells, a deep yellow-orange yolk that stands up in a round hemisphere and a white with a more viscous part surrounding the yolk and thinner area around the perimeter. Parasitic eggs come from parasitized chickens which have been fed with animal protein and fish scraps. The eggs will have flat, pale yellow yolks, thin shells and a bland taste.
Also, fill a deep bowl with water and carefully lower the egg into the water.
A very fresh egg will immediately sink to the bottom and lie flat on its side. This is because the air cell within the egg is very small. The egg should also feel quite heavy.
As the egg starts to lose its freshness and more air enters the egg, it will begin to float and stand upright. The smaller end will lie on the bottom of the bowl, whilst the broader end will point towards the surface. The egg will still be good enough to consume, however, if the egg fully floats in the water and does not touch the bottom of the bowl at all, it should be discarded, as it will most likely be bad.
Another method to test the eggs freshness is by breaking the egg onto a flat plate, not into a bowl.
The yolk of a very fresh egg will have a round and compact appearance and it will sit positioned quite high up in the middle of the egg. The white that surrounds it will be thick and stays close to the yolk.
A less fresh egg will contain a flatter yolk, that may break easily and a thinner white that spreads quite far over the plate.
To be on the safe side you must learn how to recognize the quality of eggs by their appearance after you break them. If making an omelette, break each egg into a saucer for inspection to avoid contaminating other eggs. If in doubt, discard eggs of doubtful quality or cook them hard enough to kill any parasites.
Nutritional Value of Eggs
Energy Value in Eggs: The energy value of a food is calculated from the knowledge of the macro-nutrient composition of the food. This energy value is expressed as calories or kilojoules. An average sized egg has an energy value of 78 kilocalories. We know that 4.2 kilojoules = 1 kilocalorie. Therefore, 78 kilocalories equal to 324 kilojoules. Consuming one egg per day, contributes to 3% of the average energy requirements for an adult.
Protein in Eggs: Eggs are one of the best sources of proteins. The biological value of proteins in eggs is very high, owing to the high contents of amino acids present in the eggs. It has been found that one egg consists of 6 grams of protein content and at least 9 amino acids. Proteins constitute nearly 13% of the weight of an egg. Proteins are found in both, the albumen and yolk, however, it is more prominent in the albumen part. Proteins increase the eggs nutritional value and so, diet containing high content of protein, that is preferred by people who want to increase weight and build strong muscles, always includes eggs.
Vitamin in Eggs: With the sole exception of vitamin C, eggs contain almost all vitamins. In particular, eggs are a rich source of vitamin B, especially B12 and B2 (called as riboflavin). Vitamins A, vitamin D and some amounts of vitamin E are also found in eggs.
Minerals in Eggs: For a healthy body, many important minerals are required. Eggs, in particular, are a rich source of iodine and phosphorus. Iodine as we all know, is very useful for regulating the thyroid hormone and phosphorus is equally essential for the bones.
Fat and Cholesterol in Eggs: Nearly 12% of the content of an egg is fat. Fat is found mostly in the yolk and very less percentage of the fat is contained in the albumen. The fatty acids contained in eggs are polyunsaturated (17%), monounsaturated (44%) and saturated (32%). The nutritional value of eggs in terms of cholesterol content is that, an egg contains 213 mg of cholesterol. Cholesterol content in eggs is considered to be a debating point in today's time. The cholesterol content in eggs is mainly contained in the yolk part, therefore, dietitians now a days suggest the inclusion of three white eggs in the diet, instead of two eggs with the yolk. The eggs nutritional value is considered to be lessened by the cholesterol levels, however, when we look at various other benefits, this issue is not a big factor.
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