Food Value of Edible Mushrooms from Upper-Shaba Region

F o o d Value of E d i b l e M u s h r o o m s f r o m Upper-Shaba Region I G u Y PARENT 2 AND DANIEL T H O E N 3 During our stay of several years in the south of the Upper-Shaba region of Za~'re, we observed that the consumption of wild mushrooms constitutes an appreciable food supplement for the local populations. It seemed of interest to us to try to determine the species consumed as well as their food value--this type of systematic study having not yet been undertaken in Central Africa. Our preliminary data have already been published in 1973 (Thoen et al.). Universit6 Nationale du Za/re, Lubumbashi, BP 1825, R6publique du Zai're. a Fondation Universitaire Luxembourgeoise, rue des D6port6s, 140, 6700 Arlon, Belgium. of the group Russula annulata Heim, are rejected. Finally, a mushroom which is widely encountered and eaten in other tropical regions, the SchizophyUum commune Fr., is also appreciated by the inhabitants of Shaba if prepared in a special way (this is a rather tough mushroom of the Schizophyllaceae family). What is really remarkable is the innate knowledge, shown by the local inhabitants, of the edible species--not a single case of poisoning by mushrooms is known in the region. On the other hand, it is interesting to note that certain genera are avoided by the natives; we have particularly in mind the tube-bearing Boletaceae. It seems that not one species of Boletus is eaten in the south of High Shaba or in the other regions of Za'fre. It is possible that a taboo exists regarding these species, the flesh of which often changes color on exposure to air (presence of oxidases in the flesh of these mushrooms). Some Boletus are certainly toxic but this argument does not sufficiently explain the total rejection of all the Boletaceae. In fact, the natives eat, as we have seen above, several types of Amanites, amongst which are found the most dangerous species. Besides, some of the Amanites of Shaba are considered toxic by the natives of the region. It is curious to note that, in Madagascar, the natives eat the Boletus in great quantities and ignore the edible CanthareUus which are eaten by whites (Heim, 1936). This is quite the reverse of the natives of Shaba. Mushrooms of the genus Agaricus, many of which grow in the region, are likewise avoided. Coprinus comatus, of delicate taste, is disdained (doubtless because of the rapid liquefying of its carpophores). We could 436 ECONOMIC BOTANY 31:436-445. October-December, 1977 INTRODUCTION At present, it is difficult to ascertain the exact amount of mushrooms consumed, but we can affirm that during the season favorable for the harvest (the rainy season, i.e., about 5 months), the crops amount to at least 20 tons, considering only the surroundings of the large industrial centers (Lubumbashi, Likasi and Kolwezi; about 700,000 inhabitants). Harvesting is carried out invariably by the women, mainly in the open forest (miombo) and on the large conical termites' mounds in the same forest. While collecting our samples, we carefully noted the vernacular names in the dialects of those sites in which the mushrooms were gathered (Kibemba, Kilamba and Kisanga appearing in Table 1). SPECIES OF MUSHROOMS EATEN A m o n g the species eaten, the Cantharellus occupy first place regarding the number of species and quantity harvested; these are mushrooms of small to medium size. These are followed by the Amanita and Termitomyces (Amanitaceae), which are large mushrooms (up to 80-cm diameter), except Termitomyces microcarpus (Berk & Br.) Heim, an edible delicacy but much smaller (0.5-2 cm diameter). Some of the lactaries and certain russules (Russulaceae) are eaten whilst others, such as Lactariopsis pandani Heim and the russules i Submitted for publication January 16, 1977; accepted for publication February 17, 1977. Fig. 1. Women and children harvesting Termitomyces microcarpus on a typical termitaria (photo L. Lemaire). name many examples of edible species which are not consumed by the natives of Shaba. To summarize, one can say that the inhabitants of Shaba eat about 30 species of mushrooms which they have no difficulty in identifying. Organoleptically, as regards taste and aroma, these mushrooms are much appreciated, with the exception of Schizophyllum commune Ft., a tough and odorless species. The genera most often eaten are: Cantharellus, Amanita, Termitomyces, Lactarius, Russula and SchizophyUum. Fig. 2. Termitomyces microcarpus for sale. PARENT AND THOEN: EDIBLE MUSHROOMS 437 Fig. 3. Termitorayces letestui in its natural biotope near Aloe greatheadii Schonland (photo L. Lemalre). HARVESTING OF THE MUSHROOMS Collecting the edible mushrooms begins in October just after the first heavy rains and lasts until mid-March or even until April, depending on the year. The harvest is much reduced during the short "dry season" which may occur in January, and lasts, in some years, about 10 days. At the height of the rainy season (December to March), it is quite common to see women returning with large basins full of mushrooms on their heads, the result of two Fig. 4. Termitomyces letestui offered for sale (photo L. Lemaire). 438 ECONOMIC BOTANY Fig. 5. CanthareUus div. sp. (left) and Amanita aff. aurea for sale. or three hours gathering in the course of a morning. Such harvesting is done by women working in groups. T H E SALE A N D M E T H O D S OF PRESERVING THE MUSHROOMS The mushrooms gathered are sold at the roadside, displayed on little stalls in basins or even on the ground, as well as in the markets of urban centers or important villages. The unit at the time of selling is a "kipimo" (measure) consisting of either a small receptacle filled with carpophores or else a little heap of mushrooms. The large mushrooms of the genus Termitomyces are often sold singly or even in quarters. The price of a measure is variable according to the place of purchase (town, village or roadside) and the month. Bargaining is common practice and no price is fixed. Different kinds of mushrooms are sold separately or mixed. In the case of "Ntelia" (Amanita cf. robusta Beeli), the carpophore continues opening after being picked. As this mushroom is preferred when its carpophores are still closed, the sellers offset this inconvenience by tying the cap of the mushroom with vegetable fibers, thus preventing it from opening. Many mushrooms are dried and stored for PARENT AND THOEN: EDIBLE MUSHROOMS use during the cold dry season. To do this, the larger mushrooms are cut into small pieces, then sun-dried and/or smoked over a wood fire until they become brittle. Sometimes they are slightly cooked in salted water before being dried in the sun. The large Termitomyces are directly dried on screens placed over a wood fire. T H E P R E P A R A T I O N A N D COOKING OF MUSHROOMS The methods of preparation given are those practiced in the region of Lubumbashi. The general method comprises the following steps: 1) washing the mushrooms in cold water, 2) soaking them for 15 minutes in tepid water (this step being optional), 3) cooking in boiling water for one hour, then draining off the water, and 4) cooking the mushrooms in hot palm or peanut oil, mixed with vegetables, meat or fish, and seasoned with salt and "pili-pili" (chillies). The "Ntelia" (Amanita cf. robusta Beeli) is cooked as follows: the mushrooms which are still closed (v.s.) are blanched, strangely, in boiling water, and then the caps may be peeled. The mushrooms, cut in pieces are then sauteed in oil together with thinly sliced onions and seasoned with salt and chillies. The "sepa" (Schizophyllum commune Fr.) 439 Fig. 6. Dried mushrooms for sale at the market of Lubumbashi. is a naturally tough species and requires special preparation. The natives boil the mushrooms for a long time in water to which a vegetable salt, rich in potassium, has been added; this has an effect of tenderizing. After one or two hours cooking, the drained mushrooms are mixed with sifted peanuts, seasoned with a little salt and a final addition of oil. Prepared in this way, the mushrooms are eaten with "bukari" (principal starchy dish). Table 1. List of common names. Species Amanita aff. aurea Beeli Amanita loosii Beeli Amanita cf. robusta Beeli Cantharellus cibarius Fr. var. latifolius Heinemann CanthareUus congolensis Beeli CanthareUus luteopunctatus (Beeli) Heinemann CanthareUus platyphyUus Heinemann Cantharellus cf. tuber Heinemann CanthareUus sp. Russula sp. Lactarius latifolius Goos. et Heim Lactarius cf. latifolius Goos. et Heim Lactarius cf. inversus Goos. et Heim Lactarius sp. Schizophyllum commune Fr. Termitomyces letestui (Pat.) Heim Termitomyces microcarpus (Berk. et Br.) Heim Termitomyces sp. Termitomyces schimperi (Pat.) Heim Termitomyces striatus (Beeli) Heim f. aurantiacus Heim 440 Herbarium no. Dialect Kilamba Kibemba Kisanga T.5714 T.5760 T.5694 -Mpumfia Ntelia Kiloma T.5721 T.6198 T.5697 T.5705 T.5696 T.5685 T.5579 T.5741 T.5698 T.5742 T.5545 T.4680 T.5544 T.5541 T.5578 T.5598 Bumpukutu Fumbo Kasununu Bwitondwe Kaleleka -Munia -Kisukubia Numbululu Kabansa Busepa Katoto Tande -Kinkungwa Bumpukutu Bumpukutu Kasununu Kapofu Katiletile Bwitondwe Kabansa -Katoto Musangwa -Kinkungwa T.5543 Kamenankela Kamenamakanka Furl -- Musefwe Busepa Katoto Musangwa Kakonso Kinkungwa ECONOMIC BOTANY Fig. 7. Termitomycesletestui and heaps of the little Termitomyces microcarpus offered for sale. When it comes to preparing dried mushrooms, these are simply soaked in water several hours before being cooked. FOOD V A L U E OF E D I B L E MUSHROOMS Experimental Methods Preparation of samples. The mushrooms were collected either in the field, or bought at different sale points surrounding Lubumbashi. The earth clinging to them is dusted off and they are dried whole. A representative sample (Thoen's collection) destined to be preserved and deposited in the Department of Plant Biology at the State Faculty of Agronomy at Gembloux, Belgium, is kept aside in polyethylene bags under vacuum in a desiccator. The chemical analysis will be performed on these powder samples, a part being retained for reference in the laboratory. Methods. The methods of analysis used are recognized and accepted by the A.O.A.C. (1960) and will be only summarized. We carried out each analysis in triplicate and the results in Table 1 represent the average of these determinations. Dry weight: expressed in grams per hundred grams fresh weight. The whole PARENT AND THOEN: EDIBLE MUSHROOMS mushrooms are dried by infra-red light or else lyophilized in a "Christ" (Karl Kolbe) apparatus. Results were comparable for the two methods. Proteins: expressed in grams per hundred grams dry weight. The determination of total nitrogen enabling one to obtain protein content by calculation, is performed by Kjeldhal method using 0.2 g of sample. The conversion factor from nitrogen to protein used is 6.25. Fats: expressed in grams per hundred grams dry weight. Roughly 2.0 g of sample are extracted with petrol ether (60-80~ in Soxhlet apparatus for eight hours. Crude fiber: expressed in grams per hundred grams dry weight. The method of Kursher and Hanah as modified by Ladd (in Winton, 1958) on 0.2 g of sample was used. Ash: expressed in grams per hundred grams dry weight. Ten g of sample are ashed in porcelain crucible at 600~ until a white ash is obtained. Carbohydrates: expressed in grams per hundred grams dry weight. The result is obtained by the following calculation: 100(proteins + fats + crude fiber + ash). This component comprises starch and derivatives, sugars, organic acids etc. 441 Fig. 8. "Ntelia," Amanita cf. robusta, young carpophores on open caps near maize; village in the neighborhood of Lubumbashi. Calorific value: expressed in calories per cial method by spectrophotometry: intensity hundred grams dry weight. The factors of of coloration obtained with ammonium specific energy used for proteins, fats, and molydate reagent is measured. carbohydrates are those proposed by Merrill and Watt (1955); these factors are respec- Results tively: 8.37-2.44 and 3.57. Calorific values and mineral content of Iron: expressed in milligrams per hundred edible mushrooms of High Shaba appear in grams dry weight. A.O.A.C. official method Table 2. by spectrophotometry: intensity of coloration Discussion o f Results with o-phenantroline reagent is measured. Calcium: expressed in milligrams per The average value of the dry weight is hundred grams dry weight. A.O.A.C. offi- 13.6%, with a maximum of 65% for cial method: titration of calcium oxalate dis- Schizophyllum commune. This average is solved in sulphuric acid by a standard solu- comparable to results obtained by two other tion of potassium permanganate. authors: 11.8% and 12.6% (Table 3). Phosphorus: expressed in milligrams per The average protein content is found to be hundred grams dry weight. A.O.A.C. offi- 22.7%; however distinctly higher values are 442 ECONOMIC BOTANY ,5 .-& i: b s > e-t 0 0 O3 e~ r 8 OCDO e~ .. 8 > .~ ~a0 O O3 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ 0 ~ 0 0 0 ~ 0 0 > o3 ~ I r ~d '~o3 ,.-1 ,-r ~'~ ~ ~ 9~ ~.~ ~ ~.~ ~ ~ ~ ' ~~ ,~ ~ ~ .~ .~-~.r~ .it0 .~ o . ~ ~ _~'~'~'~'~ ~ ~ ~ ~ ~ ~.~ - PARENT AND THOEN: EDIBLE MUSHROOMS -d 443 -~ .~ 9o Y~ ~ ~ ~ ~. ~ ,41 7 ~ 4 oo r c~ o ~ ~ I I d ~ dd o ~ ~o~ ~ ~'o6 o ~ _~ ~ ~. ~ -a e .~ ~ d. ~ ~" ~ .~ ~ ,~ w ~e ~ o ~ ~. s a ~ O0 t~,-~ r r~ 0 II I 0 .o 0 0 o o ~ observed for four species of Termitomyces. Our average is in agreement with the results of four other research workers (Adriano, 1933; Chinn, 1945; Adriaens, 1953; Kiger, 1959). The average fat content is 5.9%, the amanites having however an average value of 8.8%, this representing roughly 30% higher than the general average. Other authors, apart from Kiger (1959), find comparable values. The average ash content is found to be 9.0%, the average of the Cantharellus being undoubtedly higher (11.7%). Other workers have obtained comparable results to ours. The values for fiber determinations are very close to the general average of 6.8%, except for six species of CanthareUus whose fiber contents are less. The average results obtained from other authors are quite obviously higher. Although obtained by difference, the average carbohydrate content compares favorably with those shown by other authors. The average calorific value was calculated to be 301; Kiger has found higher values by applying the following factors for specific energy, namely 8.5-3.7 and 3.9 respectively for proteins, fats and carbohydrates, while the factors we used are based on those proposed by Merrill and Watt: 8.37-2.44 and 3.57. We cannot easily explain the very low average value proposed by Adriano (1933), since his methods of calculations are not readily available to us. His results have been reproduced from the paper of Gilbert and Robinson (1957). 0 r~ 0 e,I ~.~ o 444 aO ~ g.~ ~9 ACKNOWLEDGMENTS ~ 5 The authors are grateful to Professor P. Heinemann for help in the determination of some species. "~ LITERATURE CITED ~ Adriaens, E . L . 1953. Note sur la composition ,~'~ chimique de quelques aliments mineurs indig~nes du -- ~ Kwango. Ann. Soc. Belg. Med. Trop. 33(6):531-544. ~ Adriano, F. J. et al. 1933. Philippine Jour. Agr. 4:1. ~ Chinn, M. 1945. Ann. Soc. Belg. Med. Trop. 25:91. ~ ~ Franck, A. Gilbert, and F. Robinson Radcliffe. 1957. "~ Food from fungi. Econ. Bot. 11(2):126-145. Heim, R. 1936. Apergu sur les champignons toxiques ~ et comestibles des colonies frangaises. In Pathologie exotique v6t6dnaire et compar6e 3:1-31. Kiger, Cdt. J. 1959. Etude de la composition chimique et de la valeur alimentaire de 57 esp~ces de champignons sup6rieurs. Rev. de Mycol. 24:161-170, 4 tab. ECONOMIC BOTANY Merrill, A. L., and B. K. Watt. 1955. Energy value of foods. U.S. Department of Agriculture, Handbook no. 74. Thoen, D., G. Parent, and Lukengu Tshiteya. 1973. L'usage des champignons dans le Haut-Shaba. Bull. du CEPSE, 100-101:69-85. Winton, A. L., and K. B. Wiflton. 1958. The analysis of foods. John Wiley and Sons, N.Y. 470 pp. B o o k Reviews (continuedfiom page 431) Recommendations," and by a botanical subject index. The book, clothbound, is of fine physical quality for the moderate price. J.F.M. Mycology. An Outline for Science and Medical Students. Emil Mfiller and Wolfgang Loeffler; translated by Bryce Kendrick and Felix B~rlocher. 306 pp. illus. Georg Thieme Publishers~ Stuttgart, 1976. $10.50. Writing a successful textbook, besides being an exercise in patience and grim determination, requires that the author select, organize, present, and transform a corpus of heterogeneous information into a knowledgeable, coherent, attractive, and preferably readable account of his subject. Although there have been many failures, it is surprising how often the attempt has succeeded to some degree in various fields of specialization. Occasionally, a textbook earns such wide repute among students that the venture of translation has seemed justified in order to make it available to a larger audience. This is the case regarding the book under consideration, which since its publication in 1968 gained such popularity in Switzerland and Germany that a second German edition was produced in 197 i, together with a first Polish edition. Now the work has been expertly translated by Bryce Kendrick and Felix B~rlocher for use by English readers. The translators have done so well that their toil is nowhere evident, for the language flows as though the book had originally been written in English, and written with style. Slightly less than half the text is devoted to a lucid exposition of morphology, ultrastructure, metabolism, genetics, and applied mycology, the remainder being a systematic treatment of the major fungus groups. The result is a well-balanced, carefully written treatise that touches succinctly on most of the topics of mycological importance. The authors' choice of figures--whether borrowed from classical or contemporary sources--is felicitous, for they have taken care to include only material which illustrates precisely and supplements amply the subjects under discussion. No attempt is made to treat any topic in depth, nor should this be expected, since the work makes no pretention of being anything other than an "outline" for "science and medical students." Students with more than ordinary zeal, may satisfy their curiosity, at least in part, by referring to the titles in the bibliographies, which, though greatly restricted, should nonetheless be sufficient for most purposes. However, for the graduate student or even for the advanced undergraduate, the list is not adequate and should be expanded to include many more monographs as well as pertinent shorter papers. The book, of convenient small size (ca. 12 x 19 cm), has a strong flexible cover. The authors have used the inside of both front and back covers to alert the reader to the dangers of mushroom poisoning. The prominence given to this advice is in rude contrast to the sobriety of the book's contents and it would seem more discrete and no less effective if these admonitions were included in their appropriate place in the text. However, this does not detract from the overall excellence of the book. I am inclined to agree with the translators, who declare that never in a mycological textbook "has so much information on so many topics been made available for such a low cost." BERNARD LOWY Louisiana State University Baton Rouge, Louisiana B o o k Reviews (continued on page 470) PARENT AND THOEN: EDIBLE MUSHROOMS 445