GUIDELINE FOR SAFETY & QUALITY OF EGGS FOR CONSUMERS AND TRADERS BY FSSAI & MYTH OF PLASTIC EGGS
Post no 1214 Dt 19/04 /2019
Compiled & shared by-DR. RAJESH KUMAR SINGH, (LIVESTOCK & POULTRY CONSULTANT), JAMSHEDPUR, JHARKHAND,INDIA 9431309542, rajeshsinghvet@gmail.com
In the past few months, many people have raised their concern over the issue of quality of the eggs in the market. Moreover, people have also shared concerns regarding the presence of fake or plastic eggs.
People from different parts of the country have written to the Food Safety and Standards Association of India (FSSAI) about the presence of plastic eggs in the market. The FSSAI has issued a guidance note recently, which dispels the myth about plastic eggs.
In the recently issued guidance note, the FSSAI mentions that ‘plastic eggs or artificial eggs are a myth mainly due to the fact that there is no technology available to produce plastic or artificial egg that would perfectly resemble a natural egg.’
It further mentions that ‘consumers need to remember that the quality and appearance of the egg mostly depend on the way they are stored and for how long they are stored. Egg quality is best maintained when they are stored in cold temperatures preferably inside refrigerators and consumed within a period of 2 to 3 days. When kept in room temperature, several changes take place in an egg that brings about differences in the smell, texture, and appearance of the egg.
The FSSI note explains that a retailer buys an egg for Rs 4 and sells it for Rs 5 thus makes a profit of Rs 1 per egg, he will purchase and sell artificial eggs only if it is available at a lower cost. Reports state that printing an egg using 3D printing technology coasts Rs 5000 per piece. Considering the encapsulation technology which is widely used for making eggs that mimics caviar (eggs of sturgeon fish) is also very expensive. It is simply to say that motivation to create a fake product is that, the cost of production of fake product must be very less than the original. In case of chicken egg it is totally unviable to produce an artificial egg. Further it is almost impossible to make an egg that smells and tastes like a fish or chicken egg.
Moreover eggs are always subjected to testing in accredited laboratories in case of import at the point of entry. Therefore, it is highly unlikely that fake eggs would find their way into our country and be available for sell at cheaper rates.
Why some people experience fake eggs————
In this regard the FSSAI guidance note explains that, while transportation and storage, eggs undergo different temperatures. Due to this the air cell in the egg increases in volume, loses water content from the yolk and albumin due to evaporation from the shell (egg shell has 20000 small pores). The chalaza which connects the yolk and albumin starts disappearing and finely the egg loses its weight. As a consequence of water loss, the egg white and yolk portions shrinks followed by mixing of these two portions. Both these portions dissolve into each other. When such an egg is broken it does not give a separate egg yolk or white giving the impression of a fake (plastic) egg. Moreover the egg membrane in a normal fresh egg is slimy and appears smooth. With the loss of moisture this membrane becomes dry and has a paper like appearance and texture. This again creates an impression that the egg could be fake or plastic egg.
FSSAI Publishes Guidance Document on Safety and Quality of Eggs———–
The quality and safety of eggs have been in the news in recent times and so the consumers and traders are both confused. Some consumers have also been concerned about the news on plastic eggs that have been spreading rapidly. The FSSAI has not only created this document to guide consumers and traders but has also dispelled the myth about plastic eggs. It has clarified that there is no technology that can manufacture plastic or artificial eggs that would resemble natural eggs so perfectly.
FSSAI has prepared this guidance document to also explain to various stakeholders what they must look out for when assessing the freshness of eggs and how best to maintain the quality and ensure safety. It is important to note that the quality and appearance of eggs depends mostly on storage and the length of the storage period. The quality of eggs remains maintained when they are stored in cool temperatures preferably in refrigerators and consumed within 2 to 3 days. When stored at room temperature several changes take place in eggs which are related to smell, texture and appearance of the eggs.
Key takeaways for consumers————-
There are no techniques that can make an artificial egg
Eggs can lose as much quality in one day at room temperature as compared to 4 to 5 days in the refrigerator
Eggs at room temperature maintain their freshness for about 10 to 12 days after being laid and with the increase in the storage temperature their shelf life can increase
It is important to store eggs in refrigerators in designated shelves or in egg crates
Eggs that are clean, free of visible defects or cracks and which are maintained in cooler temperatures will remain fresh for 4 to 5 weeks from the time they are laid
Retailers and traders must source eggs from credible sources and store them in refrigerators
Do not use dirty or cracked eggs as cracked shells are the perfect foil for bacterial infections and dirty eggs could contaminate other food stuff.
Appropriate temperature and relative humidity (RH) need to be maintained for storing eggs in the cold store, the lack of which can result in mixing up of the yolk and albumin.
Consumers can make use of the guidance document to check the freshness and quality of eggs easily at home with the help of simple tests
Maintaining the freshness of eggs—————-
1. Eggs maintain their freshness for upto 10 to 12 days after they have been laid, at room temperature of 280 plus or minus 20, but the shelf life shortens with higher temperatures. While temperature plays a role in maintaining egg freshness but humidity is another crucial factor. The best way to maintain the shelf life of eggs is to store them in refrigerators in the designated shelves.
2. Consumers must buy eggs from stores that store eggs at cooler temperatures, that is from air-conditioned stores and supermarkets or from well ventilated covered stores that maintain ambient temperature.
3. In most cases, eggs that are clean, free of visible defects or cracks and bought from a place that stores eggs under cooler temperatures will remain fresh for 4 to 5 weeks from the time they were laid, provided that the eggs are stored in their cartons in refrigerators. Beyond this period the eggs begin to deteriorate.
4. Consumers must handle the eggs with care so they don’t crack and they must not be left in vehicles or in places where they can be affected by the hot weather. Refrigerate eggs on reaching home.
5. Do not use cracked or dirty eggs as cracked eggs can be contaminated with bacteria and dirty eggs can contaminate other foods. Dirty eggs may be contaminated even if they don’t’ smell bad. Avoid washing dirty eggs as they can become more porous when wet and this can pave the way for bacteria to enter the egg.
6. Dispose of cracked and dirty eggs immediately.
7. Always wash your hands with soap and water after handling eggs.
8. The quality of feed given to egg-laying hens is also an important factor that affects the overall quality of the egg. Eggs produced by farmers that used castor seed cakes as a source of protein were reported to have rubbery textures. Therefore, poultry feed used in poultry farms should be approved by concerned regulatory bodies like BIS, etc.
Testing Eggs for Freshness——————–
Fresh eggs when held against a very bright light in a dark room, will display a small air gap usually at the broader (blunt) end of the egg. As the egg ages, the air cells expand in volume. Upon hard boiling a fresh egg, you can clearly see the indentation left behind at the top of the egg once the shell is pealed.
In the case of fresh eggs, the yolk normally stays in the centre and is not very mobile because of the chalaza (the strings in the tissue), that hold it in place. These strings break down as the egg ages during storage or transportation. When old hard boiled eggs are cut lengthwise, one can see that the yolk has moved off centre.
A quick test to check the freshness of an egg is to immerse it in a mug or basin of water. Fresh eggs would remain at the bottom width wise, older eggs would remain at the bottom on one end while the stale or rotten ones would float because of the larger air cell. It is to be noted that sometimes weak shell and fine cracks can also cause the egg to float.
When broken out of the shell, good quality, fresh eggs display certain characteristics as mentioned below:
1. The yolk would be rounded, small and stand high in a thick gel-like egg white. The gel-like mass of egg white does not spread over a wide area but tends to stay compact.
2. As the egg ages, the egg white becomes thin and runny and finally egg yolk and white dissolve into each other in older or rotten eggs. The older eggs may also develop rotten odour and would have lost the typical egg odour.
3. With the aging of egg and the white becoming thinner, one can clearly notice that it will take longer to whip into foam, and when whipped the foam is less stable or collapses faster.
4. However, it is also important to note that very fresh eggs also do not foam well and take longer time; but, once beaten the foam is very stable as compared to older eggs.
5. The maximum and better foam volume/ stability can be obtained from three or four day old eggs.
If not stored properly, eggs become plastic-like——————–
The way eggs are stored is as important as for how long they are stored. Eggs can lose as much quality in one day at outside high temperature, as they would lose if kept 4 to 5 days in the refrigerator. Eggs kept at the room temperature can maintain their freshness for up to 10 -12 days after being laid, but the shelf-life reduces with increase in storage temperatures.
The changes that happen in an egg as a function of storage can be slowed down if fresh eggs are placed in cooler storage. Also, shells can be covered with a thin layer of approved oil, particularly over air cells.
While transporting and storing, eggs undergo different temperatures. Due to this, the air cell in the egg increases in volume loses water content (through more than 20000 pores in the eggshell) from the yolk and albumen due to the evaporation through the shell. The chalaza, a funnel-shaped protein matter that connects yolk and albumen starts disappearing and finally the egg loses its weight. A normal fresh egg weighs around 50-65g while older or rotting eggs would lose about 15-20 g of weight. The increase in air cell volume can be easily detected by piercing the broader end of the egg with a pin. A normal fresh egg does not give away easily while an older egg simply gives in due to increased air cell.
As a consequence of water loss in eggs, the egg white and yolk portions shrink followed by the mixing of these two portions. Both these portions dissolve into each other, and when such an egg is broken it does not give a separate egg yolk or white giving the impression of a fake or plastic egg. Moreover, the shell membrane in a normal fresh egg is slimy in appearance and texture. This again creates the impression that the egg could be plastic or fake. One should note that the membrane of a fresh egg would take time to burn when held against a flame, while the membrane of the older (fake or plastic) egg would burn quickly due to its dryness, but both would produce the same kind of ash without a hint of smell that is normally associated with burning plastic.
Consumers can find out if the egg is genuine by simply dipping the shell pieces of suspected fake or plastic egg in string acids like 2N hydrochloric acid. Calcium carbonate, being the major component of eggshells, will dissolve the shells in the acid. Alternatively, egg or eggshells when placed in vinegar will dissolve the shells slowly but will start giving out bubbles and even sometimes makes the eggshells float, in case of pieces. The membrane of such acid treated shells will have no adhesion to the shells but will almost have the texture of paper or thin plastic.
Plastic eggs- a myth——————–
There is no technology that can make perfect artificial eggs though eggs can be made by combining several ingredients like calcium chloride, alginate, and dyes or encapsulating fish eggs. However, all these processes are labour intensive and expensive and so there is little chance that a trader would purchase “artificial” eggs that are not going to give them good returns. The production of eggs in our country in 2016-2017 was 88.1 billion, which means that they sell at very thin margins so why would a trader buy the more expensive artificial eggs and get almost no profit. Moreover, making an artificial egg would require professional skills to encapsulate fish eggs and so the motivation to create fake eggs is very low. Also, add the fact that eggs can be tested in accredited food testing laboratories anytime as they are a risk product and they can also be subjected to testing in the case of imports. It is quite difficult to imagine that the expensive fake eggs would be able to come into the country and be available for sale at rates which are economically viable and cheaper than the present rate of eggs.
For traders and retailers—————–
Source eggs from credible sources only
Traders and retailers can minimise the decline in egg quality by observing the following basic guidelines
1. Have adequate and cool holding places to store eggs preferably refrigerated
2. Avoid storing eggs close to strong smelling food or food products
3. Store and display eggs away from sunlight
4. Strictly rotate the eggs on FIFO (First in First out) basis. Keep the older stock in front of fresh stocks so that all eggs sold are as fresh as possible
5. Avoid transporting eggs in hot vehicles or hot temperatures
6. Advice the consumers to store the eggs in a cool temperature or in refrigerators
7. Immediately discard any cracked or dirty eggs
8. Do not sell dirty eggs to consumers
For regulatory staff and laboratories——————–
Sample condition:
eggs samples collected for analysis should preferably be transported under cool temperatures without subjecting them to higher temperatures. It is advisable to transport eggs in cartons or egg cases when they are being sent for analysis.
Screening and confirmation:
screen any suspect fake egg sample for true protein by Biuret’s/Lowry’s as well as Kjeldahl methods. Natural chicken eggs(whole) would generally have a protein content between 11.5 to 12.5 percent, lipid content of 11.5 – 12 percent and almost no carbohydrates (<0.5 percent if any). Since the egg is known to have the most desirable amino acid composition, next only to milk, the amino acid composition will also help to distinguish the normal eggs from allegedly fake eggs.
