How do you know if fruit is fresh?

You can see the root, freshness of the fruit.

Watermelon is a good time to eat watermelon, but it is not easy to pick a good melon. Serkov, a Russian expert with 20 years of experience in melon crop cultivation, introduced the experience of picking melons here on the 17th. According to Sykov, there is some truth in the folk saying that watermelons are divided into "male and female" from his own experience.

On the other side of the melon skin opposite the guati, there is a round lumpy tissue, commonly known as the "navel", the "navel" of the "male" watermelon is smaller, while the "female" watermelon is larger, the size of a coin, and the "female" watermelon is sweeter than the "male" watermelon. Don't forget to pay attention to this feature when picking melons. In addition, you should choose the larger watermelon of the same type, which is more ripe and therefore sweeter.

At the same time, when picking watermelons, you should first pat them and listen to the sound they make, the sound of ripe watermelons is louder and more powerful. Some people think that the guati is dry and means that the watermelon is ripe, but this view is not comprehensive, and some watermelons will also dry up after being stored for a long time. In terms of the pattern of watermelon skin, the more obvious the distinction between dark and light stripes, the better, if the pattern is blurred, it is likely that too much nitrate fertilizer is applied when planting watermelon.

When the watermelon is ripe, the part of the watermelon that touches the ground should be yellow or orange, not white, if it is white, the watermelon is likely to be unripe. In addition, the skin of the melon should be hard and elastic, pinch the skin with your fingernails when picking the melon, and if it is soft, you can consider changing it. Do not pick watermelons that are placed directly on unclean ground, because watermelons will "breathe" after being picked, and the skin of the melon has a strong adsorption capacity.

The female watermelon is indeed sweeter than the male. Oranges are also male and female: those with prominent dots are female, and they are better to eat; Those who do not protrude from the dots are male, and they are relatively poorly eaten.

Dangshan pears are also male and female: those with pedicles at the bottom of the pear are male, and the flesh is relatively coarse; If you don't get it, it's a female, and the meat is relatively fine and sweet. Understanding that plants have sex is a great step forward for human beings.

In fact, not only are the plants themselves "male and female", but even their fruits have genders. Researchers say that not only are there differences between males and females, but that female fruits are much tastier than male fruits. The male and female of apples are mainly manifested on the fruit pedicles.

The larger fruit pedicle is the female fruit, which is sweet and refreshing, juicy and thin-skinned; The small fruit pedicle is the male fruit, which is both sour and astringent, with little juice and thick skin.

Wrap a layer of plastic cloth on the fruit so that their water should not evaporate, and then drop some water on the plastic cloth to cool down, which can also reduce their water evaporation, so as to keep them fresh!

Always get some water on it, as if it can keep it fresh.

Store at room temperature until the ripeness is enough, and then store it in the refrigerator, which can keep the fruit fresh.

It is recommended to put crusty fruits directly in the refrigerator, such as: watermelon, pineapple, cantaloupe and other fruits.

Thin-skinned and soft-skinned fruits are packed into plastic bags before being put in the refrigerator. Such as apples, pears, mangoes, etc.

If you put it in the refrigerator for a long time, the shell will become dry and black, and affect the flavor of the pulp, so it is recommended that you spray a little water on the fruit before putting it in a plastic bag to maintain the fresh taste of the pulp. Lychees can be cut one by one with scissors, immersed in salted water for a few minutes, then scooped up, and then put into a plastic bag and put in the refrigerator to retain their flavor for a long time.

Fruit preservation method Friends who often eat fruits know that eating more fruits can delay aging, regulate the stomach and prevent high blood pressure. Aunt Yan used this method to preserve apples for 2 months. Put a glass of water in the middle of the apple, it seems that Aunt Yan is using the principle of continuous evaporation of water in the water cup to replenish water to the fruit to keep the fruit fresh, let's take a closer look at how Aunt Yan does the long-term preservation of apples or pears!

First put the basket or basket of apples in a plastic bag, pour more than half a cup of water into the small cup, put the water cup into the basket, and then put the apples into the basket. Another layer of plastic bags, also tie the bag mouth, two layers of plastic bags can effectively reduce the evaporation of water from the bag, usually put the wrapped basket in a cool place, generally within 20 degrees Celsius environment, can keep the fruit fresh for more than 2 months, when you need to take the fruit as long as you open the lid can eat fresh fruit at any time.

It is best eaten in the stomach and absorbed most freshly.

Here's how to tell if a fruit is fresh or not:

1.Acidity is measured to determine the ripeness of fruits and vegetables.

For example, if malic acid is higher than tartaric acid in the organic acid contained in grapes, it means that the grapes are not ripe, because ripe grapes contain a lot of tartaric acid. The acid content of different kinds of fruits and vegetables varies according to the maturity and growing conditions, and generally the higher the ripeness, the lower the acid content.

For example, in the ripening process of tomatoes, the total acidity decreases from the green ripening stage to the full ripening stage, and the sugar content increases, the sugar-acid ratio increases, and it has a good taste, so the maturity of the raw materials can be judged by the measurement of acidity.

2.You can judge the freshness of the food.

For example, if the lactic acid content of fresh milk is too high, it means that the milk has spoiled; The presence of free galacturonic acid in fruit products indicates contamination by moldy fruits.

3.Acidity reflects the quality indicators of a food.

The amount of organic acids in food directly affects the flavor, color, stability and quality of food. The determination of acid has certain guiding significance for the microbial fermentation process. Such as:

In the production of wine and alcohol, there are certain requirements for the acidity of wort, fermentation broth, koji, etc. Acids in liquor, beer, soy sauce, vinegar, etc. in fermented products are also an important quality indicator. In addition, acids play a significant role in maintaining the acid-base balance of human body fluids.

Each of us also has certain requirements for the pH value of body fluids, the pH value of human body fluids is, if the pH value of human body fluids is too large, it will cramp, and if it is too small, acidosis will occur. Acidity in food is usually expressed in terms of total acidity (titrated acidity), effective acidity, volatile acidity. Total acidity refers to the total amount of all acids in a food, including the concentration of dissociated acids and the concentration of undissociated acids, which is titrated with a standard lye solution and expressed as the percentage of the main representative acid in the sample.

Effective acidity refers to the concentration of hydrogen ions in an ionic state in a sample (strictly speaking, activity) measured with a pH meter and expressed as a pH value. Volatile acidity refers to the volatile part of an organic acid in a food. Such as acetic acid, formic acid, etc., can be determined by direct or indirect methods.

Look at the color, smell the taste, and touch the texture.

The surface is bright, and there are no insect spots