Why does the milk powder I bought turn yellow after a long time?

Although milk looks white, there are many trace ingredients that are colored.

For example, lactoferrin.

It is one of the important active ingredients in milk, it is red when purified.

Of course, the main color components in milk are carotene and lutein.

such as vitamin B2

That is, riboflavin.

In the early days, this vitamin was extracted from milk or eggs until the method of artificial synthesis appeared.

Carotene and lutein come from pastures, so the milk is yellowish in summer and autumn when grazing, and white in winter when fed.

However, the content of these colored ingredients is very low and is not noticeable in liquid milk.

When the milk powder is concentrated from liquid milk into milk powder (the concentration ratio is about 7:1), the milky yellow color is revealed.

Maillard reaction].

Turning milk into milk powder is the removal of water, which needs to be treated at high temperatures.

At high temperatures, milk proteins.

Amino acids and sugars undergo a "Maillard reaction" that produces a browning effect.

The higher the heating temperature, the longer the time, and the greater the degree of browning.

Some imported milk at room temperature has obvious browning, which is due to the long time of high temperature sterilization.

But you don't have to worry too much, because the Maillard reaction is so common that it is used in home cooking.

The Maillard reaction in milk processing has a limited nutritional impact, and the Maillard reaction also produces many complex compounds, which are one of the main flavors of food.

Light scattering] In addition to the above two chemical factors, there is also a physical phenomenon that intensifies the white color of milk.

Milk fat is contained in milk, which is evenly suspended in the form of tiny droplets.

These small droplets act like lenses to refract, reflect, and scatter light, resulting in a whitish visual effect.

If you put a few drops of cooking oil in half a bottle of water.

Then shake vigorously for a minute, and you can also see the white emulsification.

With all that said, what do different colors mean for you to choose milk?

In fact, whether it is liquid milk or milk powder, whether pasteurized milk.

It is still room temperature milk, and the main factors affecting its nutritional value are milk protein, milk fat and milk calcium.

and not the color of the milk.

As long as you have a glass of milk (300 ml) a day, no matter what color it is, it will be good for your health.

Because of deterioration, this phenomenon will occur if the milk powder expires, and bacteria will begin to breed, so be sure to drink the milk powder within the specified time, and if it turns yellow, don't drink it, which is harmful to health.

If you haven't drunk milk powder for a long time, even if it hasn't expired, it will oxidize and turn yellow in color.

I think if the milk powder I bought turns yellow, it means that it has gone bad and there is no way to eat it.

In the process of milk powder transportation, the powder of milk powder will produce static electricity due to friction against each other, so the milk powder will form a clump, and after opening the can, you will find that the milk powder has formed a small clump, no need to worry, as long as you gently push it away with a spoon, the milk powder will immediately become a smooth powder, its nutrients and quality are not affected, it is not a quality problem, and you can eat it with peace of mind.

When the package is opened and not sealed in time, it absorbs the moisture in the air, resulting in clumps; Secondly, the spoon used to prepare the milk powder adheres to the water and comes into contact with the milk powder in the jar, which will also cause the milk powder to clump.

Alternatively, due to "brutal" loading and unloading during transport, the tank body is damaged, which can also cause the milk powder to deteriorate after entering the air.

Or if the can is opened for too long, the milk powder absorbs moisture in the air for a long time, resulting in the milk powder regaining moisture and deterioration.

Bao Ma. Say, every time I drink milk, there is always a dissolved milk powder in the bottle, and ask me if such milk powder is of bad quality?

Of course not! 1.Because the proteins and fats in the main ingredients of infant formula are insoluble or slightly soluble in water.

2.The preparation method also affects the solubility of the milk powder.

For example, too much milk powder is put into the milk powder at one time, and the speed is too fast, resulting in the powder particles of milk powder not being in full contact with water, which affects its dispersion in water. The milk powder blocks that are not dispersed are moist on the outside and form an impermeable "diaphragm", and water cannot enter the inside, so they become milk blocks that are difficult to tolerate "wet on the outside and dry on the inside".

Even if you shake the bottle vigorously, you won't be able to break it up.

Note: If the baby's milk powder dissolves very quickly, it will melt when it is added to the water, and it will automatically dissolve or precipitate without shaking. Or open the milk powder package, put it in the mouth to taste, the milk powder dissolves quickly, does not stick to the teeth, and has a strong sweetness, then most of such milk powder is fake milk powder, and it is not recommended to give it to the baby.

If the milk powder is left for a long time, the color is yellow and cannot be eaten. Generally, the shelf life of bagged milk powder is one week, and the shelf life of canned milk powder is one month after opening. If you leave it for too long after opening, it will be contaminated by bacteria, and the bacteria will secrete a lot of toxins, which will harm the human body.

Milk powder has the inherent flavor of sterilized milk, which is dry and powdery and has no agglomeration. Usually the color is pale yellow and white, but if the color of the milk powder turns yellow and cloudy over time, it can no longer be eaten. <

If the milk powder is left for a long time, the color is yellow and cannot be eaten. Generally, the shelf life of bagged milk powder is one week, and the shelf life of canned milk powder is one month after opening. After the milk powder is opened, it will be contaminated by bacteria for too long, and the bacteria will secrete a lot of toxins, which will harm the human body.

Milk powder has the inherent flavor of sterilized milk, which is dry and powdery and has no agglomeration. Usually the color is pale yellow and white, but if the color of the milk powder turns yellow and cloudy over time, it can no longer be eaten.

Under normal circumstances, the color of milk powder is natural light yellow, if the yellow of milk powder is too dark or burnt yellow, and the color is different from the color when opened, then it is most likely bad and should not continue to eat. In addition to the darkening of the color of the milk powder, it is best to throw it away, so it is best to throw it away.

When buying milk powder, pay attention to check whether the packaging of milk powder is qualified, whether the manufacturer is regular, the length of the shelf life and other information, and choose fresh qualified Peilun milk powder is more guaranteed.

Good milk powder smells with a milky fragrance, tastes slightly sweet, the powder is dry, loose, and no lumps.

It is best to ensure that your hands are dry when scooping up milk powder, so as not to get damp with the milk powder, seal and cover tightly with a lid after each take, and place it in a cool, ventilated and dry place.

Question 1: What should I do if my baby drinks spoiled milk powder The impact of spoiled milk powder on babies is different for each baby. Some may have diarrhea, some may vomit and diarrhea, etc.

Because of deterioration, it will be toxic and will cause some damage to the baby's stomach. But don't worry too much. Because the spoiled milk powder must be judged by us.

You have to see how your baby reacts. In the future, remember that the prepared milk powder should be drunk by the baby immediately, and if the baby does not drink it, you will drink it, and do not let the baby drink the remaining milk powder. The water temperature of the milk powder must be controlled at 40 degrees.

In this way, the baby can drink it. Once in winter, I gave the baby apples, afraid of the cold, I soaked in hot water, but the result was soaked for a long time, and the baby had diarrhea after eating. In the past, I soaked it and ate it, but I didn't have anything at all.

So be sure not to let the baby eat leftovers, things that take a long time. Newborns should not drink milk powder that has been left for a long time.

Question 2: What happens if you drink expired milk powder Eat expired things will be easy to have diarrhea Question 3: What will happen if you drink expired milk powder At most, the shelf life is not written on the outer packaging, and the dumex drunk at home is available on the packaging, and the shelf life is one and a half years.

Question 4: What will happen if a one-and-a-half-month-old baby drinks spoiled milk powder It is possible to have diarrhea or get sick.

Summary. You can drink it. The yellowing of milk powder is mainly due to the color change caused by oxidation or other reasons, and it does not have much impact on health.

However, in order to ensure quality and taste, it is best to use fresh milk powder as soon as possible. If the milk powder has a peculiar smell or has changed significantly, it is better not to eat it. Remember to follow the storage method of milk powder, store it in a dry, dark and ventilated place, and prepare it according to the instructions for use.

You can drink it. The yellowing of milk powder is mainly due to the color change caused by oxidation or other reasons, and it does not have much impact on health. However, in order to ensure quality and taste, it is best to use fresh milk powder as soon as possible.

If the milk powder has a peculiar smell or has changed significantly, it is better not to eat it quietly. Remember to follow the storage method of milk powder, store it in a dry, dark, and ventilated place, and at the same time follow the instructions for use to prepare it in several rows.

Can you add, I don't quite understand it.

The yellowing of the milk powder is a color change caused by oxidation or other reasons, and has little impact on health. It is recommended to use fresh milk powder as soon as possible to avoid odors and obvious changes. The storage of milk powder should follow the preservation method, put it in a dry and dark and ventilated place, mold it and prepare it according to the instructions for use.