Dumpling leaves are green and will gradually turn yellowish green or yellowish brown after being placed for some time. Experienced seniors will soak the leaves in water to preserve them, or hang them to dry, and then put them in water to soak and recover when they are ready to eat.

Some manufacturers of rice dumplings in order to ensure that the rice dumplings "look good", in the soaking of rice dumplings to add industrial copper sulfate and industrial copper chloride to the water, so that the rice dumplings will be able to achieve the "green" effect.

The market dumplings with reed leaves, Ruo bamboo leaves. Dumpling leaf color green, does not mean that the dumplings fresh, but may hide hidden safety hazards. He pointed out that the green zongzhi leaves mainly from chlorophyll, but chlorophyll is a very unstable pigment, zongzhi leaves by high temperature, the influence of oxygen, the color will become yellow and brown.

The dumplings are transported and stored, and consumers meet with the dumpling leaves is difficult to maintain a fresh green; steaming and cooking, the dumpling leaves will be more difficult to maintain the green.

Extended information:

Guangdong selection of zongzhong leaves and zongzhong ropes small tips:

1, Western Guangdong - dumplings leaves reed effect:

Western Guangdong people used to use dumplings leaves reed (also known as mangrove) to wrap dumplings. Dumpling leaf reed mainly grows in Guangdong, Guangxi and other places in the mountain slopes, valleys or under the trees, easy for villagers to pick and sell, is said to have a cough and asthma, clearing heat and dampness and other effects.

There is also a kind of rope with dumplings in western Guangdong, called fake pineapple dumplings vine, its toughness is very good, not easy to break. This pair of "best partner" package out of the zongzi especially strong. There are many years of experience in wrapping rice dumplings, said Aunt Leung, wrapped rice dumplings before the first rice dumplings and false pineapple rice dumplings vine thoroughly cooked, and then soaked for a night, and then use a brush to brush the leaves one by one, or else wrapped rice dumplings will be bitter and yellow.

2, Dongguan - banana leaves emit a wisp of fragrance:

Dongguan Ma Chung abounds in bananas, large banana leaves can be found everywhere. Therefore, the villagers on the ground, with banana leaves wrapped zongzi, made banana leaf zongzi and wearing reed leaves or Ruo leaf zongzi flavor is different.

The eve of the Dragon Boat Festival, a lot of Ma Chung people to go around the banana plantation to pick the right banana leaves, soaked in warm water and washed, cut the size of the leaves used as dumplings. Wrapped banana leaf rice dumplings need to be cooked on an open fire for about 5 hours, and the dumplings should be completely immersed in water, so that banana leaf rice dumplings will not hide "folder raw rice".

3, chao shan - "gardenia rice dumplings" also need to be salty grass with:

"gardenia blossom, so lovely." Little-known is, in the Chaoshan area, people like to use gardenia to the glutinous rice for coloring and seasoning, and then use the salty grass to wrap, make the festival characteristic snack "gardenia rice dumplings".

Gardenia's branches and leaves never wither in all seasons, the fragrance is attractive, gardenia fruit has been used as dye since ancient times. In shantou senior technical school teacher ChenWenXiu view, use gardenia to food for coloring and flavoring, is a great creation of the Chaoshan people.

4, heyuan - rice stalks for rope is very environmental protection:

Heyuan Hakka people package zongzi generally use the countryside common Ruo leaves, banana leaves and other materials, bundled zongzi rope to rice stalks, bamboo gimlets, wick grass or cattail grass mostly, the use of these natural materials are both environmentally friendly and practical.

People dry the straws in the sun during the summer or fall harvest each year, and then use them to wrap zongzi during the Dragon Boat Festival.

Baidu Encyclopedia - Rice Dumpling Leaves

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People's Daily Online - Rice Dumplings "is the leaf floating incense Guangdong selection of rice dumplings leaves and rice dumplings rope have these small tips