Bulletin Winter 1975

Q. Chinese mushroom is an inexpensive food with high protein content. What in fact is the nutrient value of this kind of mushroom? Is it even higher than that of white mushroom? A. Chinese mushroom, like all other mushrooms, has a higher mineral salt content than meat or fish, and almost twice as much as any other vegetable. Their protein value, though much less than meat and fish, is double that of asparagus, cabbage and potatoes, four times that of tomatoes and carrots, and six times that of oranges. Fresh Chinese mushroom has also a certain quantity of vitamin C. Studies have shown that Chinese mushroom surpasses the white mushroom in nutritional value. Q. It is said that edible mushrooms have medicinal properties and can even cure cancer. Is it true? A. Devoid of starch, it is an ideal food for diabetics, and although no experiment has yet been done to demonstrate its value for hypertension, it is known to help reduce excessive, cholesterol. As for the cure of cancer, experiments have been carried out in many parts of the world to extract anti-cancer components from edible mushrooms and reports have been published. A detailed exposition is given by Prof. K.W. Cochran of Michigan University in his paper on the Medical Effects of Edible Mushrooms. [This paper will be included in The Biology and Cultivation of Edible Mushrooms edited by Dr. Chang and Dr. W.A. Hayes of The University of Aston in Birmin g ham.] Q. Did you undertake research on the cultivation method of Chinese mushroom because of the world-wide food crisis? A. Literature on the study of Chinese mushroom being scarce, I have, since 1962, been interested in the study of its nutrients, physiology, cytology, ultrastructure, genetics, morphogenesis as well as its cultivation. The way in which mushrooms can be grown from a great variety of cheap (some almost worthless) materials such as agricultural and industrial wastes greatly enhances their importance as food. Besides, the fruiting bodies of Chinese mushroom appear in the beds within 8—14 days, no other cultivated mushroom produces a crop in such a short time. Although Chinese mushroom cannot help to alleviate the world-wide food shortage as staple food, it may constitute a valuable source of supplementary food through mass production, and help to produce a more diversified diet and better quality foods. Q. You suggested using cotton waste beds to cultivate Chinese mushroom instead of the conventional straw beds. What are the advantages of this new method? A. In Hong Kong, the price of cotton waste is only one-third that of dry straw. Moreover, local supply of rice straw is scarce. The small amount available is mostly consumed by the Royal Hong Kong Jockey Club and import of this material has proved to be very expensive. On the other hand, cotton waste, being a by-product of local textile industries, is easily obtainable and inexpensive. The yields for cotton waste beds is three to four times that of rice straw bed, their average yields are 35 kg per 100 kg cotton waste and 10 kg per 100 kg straw. In 1970 we started experimenting by using cotton waste as heating material and straw as composting material to cultivate mushroom, later only cotton waste was used and the result turned out to be very satisfactory. I believe the mushroom cultivating industries in Hong Kong will soon be depending solely on cotton waste as cultivation material. Q. Mushroom cultivating industries? Are there any such industries in Hong Kong? A. Yes, at Lau Fau Shan, but their yield is far from satisfactory. In the summer months of April to October, Hong Kong people consume nine tons of Chinese mushroom a day, only 7% of which is produced locally. I feel that there is yet much room for development. Q. I heard that you have rented a piece of farmland in the vicinity to experiment on mushroom culture. This must have helped you a lot in your research. A. Yes, but mushroom culture experiments are carried out on the University campus now. 12