1. Look at hardness: the hardness of new rice is greater than that of old rice-the greater the hardness of rice, the higher the protein content and transparency. You can tell whether it's new rice or old rice by biting it with your teeth.

2. Look at the belly white: The belly white of new rice should be milky white or light yellow, while the color of old rice will become darker and even brown.

3. Look at the yellow grains: The yellowing of rice grains is caused by the chemical reaction of some nutrients in rice under certain conditions or the proliferation of microorganisms in rice grains. Such yellow rice will affect the flavor and taste of rice. The new rice grains are even and shiny, and the surface of rice grains is gray powder or old rice with white furrows, and the more white furrows and gray powder, the older they are. It is obviously old rice who has a musty smell and is eaten by insects.

4. Insert your hand into a rice bag or barrel, and observe your hand surface after pulling it out: there is a little white flour, which can be easily blown off, which proves to be new rice, while those that can't be blown off lightly and have oily mud are old rice or inferior adulterated rice.

5. Moisture and aroma: The moisture in the new rice granules is more than that of the newly ground rice in Chengu, and it feels very sticky when it is squeezed by hand. The freshest rice can even be squeezed into a ball, but old rice can't pinch it like loose sand, which is stiff. New rice smells like rice, but old rice doesn't.

first, observe the germ (commonly known as "rice eyes") retained at the base of the abdomen of rice. The germ of new rice (its color is milky white or light yellow) is mostly retained at the base of the abdomen of rice. Of course, the number of germs retained is related to the mechanical strength and the length of rice milling, so it cannot be generalized. However, in any case, the germ of new rice can always be retained in part or most, which is very clear to the naked eye, and the immature rice can be seen as cyan (commonly known as green waist). Old rice germ (brown) basically does not exist, even if there are a few, it is almost difficult to find, leaving a white gap at the place where the germ falls off;

second, the new rice should be crystal white and have a strong fragrance, which is refreshing and is the "anti-counterfeiting trademark" of the new rice. Chen Gu's newly processed rice has little fragrance, while old rice, which has been stored for more than one year, has only the taste of rice sugar and no fragrance. If there are many yellow grains, musty smell, worms and lumps in old rice, it means that it has deteriorated and should not be bought and eaten;

thirdly, if you put your hand into the rice, white starch will get on your hand, which is not the case in old rice.

In addition, when judging whether rice is new or not, a reagent recently developed by Tianjin Academy of Agricultural Sciences-"Bumiling" can test the quality of rice. Just sample 2-3 grains of rice, and drop a few drops of "Mi Mi Ling Liquid". Within one minute, the rice freshness can be determined by the color change: the new rice is light green, the half-aged rice is light yellow, and the old old rice is red. Whether it is fashionable "cosmetic rice" (treated with mineral oil or polishing) and "green rice" (smoked with bamboo leaves or soaked with tender bamboo shoots, which is artificially dyed) or new rice mixed with old rice, it can be accurately detected.

In addition, when you go to supermarkets, farmers' markets or buy bagged rice from rice vendors who sell rice in the community, you should pay attention to whether the packaging bag is marked with information such as enterprise logo, production date and place of origin.