With the approaching of Tung Ng Festival (aka Dragon Boat Festival), eating zongzi (aka glutinous rice dumplings) is traditionally for celebration. A huge variety of zongzi are being sold on a local market, in which are largely made of glutinous rice stuffed with different fillings, like salted egg yolk, pork and mung beans. Over recent years, many people prefer to produce homemade zongzi for the reasons of health or sheer fun.

The leaves for wrapping zongzi are requisite aside from other ingredients, such as glutinous rice and stuffing. These are direct contact with the food, but the quality is often overlooked. Here are four essential skills needed in selecting and handling of the leafwraps, namely ‘Visual Observation, Smell, Enquiry and Wash Thoroughly’.

First of all, what kinds of leaves are used for wrapping Zongzi?

Among the plant diversity of leaves, reed and large-leaved bamboo are the ones commonly used as leaf wrappers for zongzi. The bamboo leaf of the species Indocalamus tessellatus is the usual choice in southern China, and reed leaf is mainly used in northern China. Other kinds include lotus leaf, banana leaf and daimyo oak leaf (i.e., a species of Quercus dentata).

Four Basic Skills, 'Visual Observation, Smell, Enquiry and Wash Thoroughly ', For Buying and Preparing the Leafwraps of Zongzi

• Observe the colour of leafwraps. If the leaves are inordinately green or greenish bright, these possibly have been treated with‘Dyes’. There had been incidents in China that some immoral merchants adulterated the industrial-grade copper sulphate or copper (II) chloride into water for soaking the leafwraps. This intended to restore the discoloured leaves into a bright green appearance, making them look more appealing to customers. Nevertheless, these chemicals have never been passed the food safety assessment and the usage approval, also dissatisfied the food safety and hygiene requirements.
• Smell the leaves to check whether impart an unpleasant scent of chemical. Generally, sulphites are utilized in the dehydration process of fruits and vegetables. In this case, the leafwraps treated with sulphite solution aim to preserve their colour, prevent from yellowing and look more attraction. The sulphites work as a preservative by releasing sulphur dioxide gas, which may remain as residues in the leaves. Intake of residual sulphur dioxide in excess amount may result in vomiting and other bodily discomfort.
• Enquire about the source, quality and relevant information of the leaves. Always buy them from reputable shops.
• Wash the leaves thoroughly with clean water to remove foreign matters and residual substances. Since sulphur dioxide is water-soluble, the leafwraps that are washed, soaked and cooked with water can reduce the amount of residual sulphur dioxide. 

Finally, the public should maintain a balanced diet, and do not eat too many zongzi because of containing high calories and fat.