[How does yam stay black]_How to do_How to do

04/26/2020 0 Comment

[How does yam stay black]_How to do_How to do

Yam is a very popular food, and it is also a kind of food that promotes human health and has a better effect.

But the biggest problem when eating yam is that it will turn black.

This is mainly because yam contains polyphenols, polyphenol oxidase and other substances. If combined with oxygen, it will cause yam to turn black.

In fact, as long as you master a certain method, yam will not turn black.

First, why does the cut yam easily turn black?

The darkening of the cut yam is due to the browning of the enzyme resulting in a darker color.

There are three main conditions for browning: polyphenols, polyphenol oxidase and oxygen.

After the yam is peeled and exposed to the air, the polyphenols in it react with oxygen to generate a neighborhood, and then oxidative polymerization forms brown pigment and melanin.

This kind of situation is rare in real life. After peeling, apples, eggplants, lotus roots, etc. will be browned by enzymes, which will cause the color to become darker. Soak the peeled yam in cold water to replace it with oxygen in the air.It won’t change color.

If you eat, there is no problem, but the color is not good after cooking.

Second, how to prevent the cut yam from turning black?

1, cut yam is not to use metal props (stainless steel can be used) with wooden or expected knives.

2. Soak the sliced yam in cold water with salt water or oiled vinegar, or soak in lemonade. Wait until the yam is fried before leaching in water.

3. You can also fry yam first.

Third, how to preserve yam?

1. Short-term preservation method of yam If you don’t eat yam immediately after purchase, you should immediately handle it properly to ensure the quality and taste of yam.

The specific processing method is as follows: ① After the yam is peeled and cut into pieces, it is divided into plastic bags according to the amount of food consumed each time. After being packed, it should be put into the upper layer of the refrigerator for rapid freezing.

② Yam does not need to be thawed when consumed. It can be boiled when the water is boiled, which is convenient and can ensure the quality of yam.

2. Long-term preservation method of yam ① Room temperature ventilation method: If the ventilation facilities at home are good, it can be stored in room temperature ventilation. Using this method can generally be stored 3?
For 6 months, don’t pack yam in plastic bags and newspapers when storing, it is better to spread them out.

② The rice wine soaking method is not often used because it is not used well and will damage the taste and quality of yam.

The method is to break the yam, soak the upper part with rice wine, blow dry it with a hair dryer, gradually cut off the mouth to heal, and finally remove the tissue paper and wrap it, and store it in a cool place for several months.

③ According to the refrigerator-freezing method, yam is at 1?
It can be stored at a temperature of 4 ° C for about 3 years. Therefore, the yam bought in the summer can be immediately placed in a refrigerator to be refrigerated.

When yam is refrigerated, it should be separated from the fruit to prevent the yam from spoiling due to the ethylene released by the fruit.

④ Cold storage method This method is suitable for large-scale storage of yam planters or yam processing plants. When using this method, the temperature of the cold storage should be kept at 2 for many years?
6 ℃, so it can be stored for several months.