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A preliminary report on the nutrient content of Coprinus comatus
S. Afr. J. Bot., 1983, 2(1)
A preliminary report on the nutrient content of Coprinus comatus Adriana Winterboer and A. Eicker• Department of Botany, University of Pretoria, Pretoria 0002, Republic of South Africa
A.S. Wehmeyer Division of Food Chemistry, National Food Research Institute, CSIR, P.O. Box 395, Pretoria 0001, Republic of South Africa •To whom correspondence should be addressed Accepted 6 September 1982
The nutrient content of Coprinus comatus (MOll. ex Fr.) S.F. Gray was determined and compared with that of Agaricus brunnescens Peck. It was found that the nutrient content of C. comatus is comparable with that of A. brunnescens. Die voedingstofinhoud van Coprinus comatus, (Mull. ex Fr.) S.F. Gray is bepaal en vergelyk met die van Agaricus brun· nescens Peck. Daar is gevind dat die voedingstofinhoud van C. comatus vergelykbaar is met die van A. brunnescens. Keywords: Agaricus brunnescens, Coprinus comatus, nutrient content
83 the National Food Research Institute of the C.S.I. R. in Pretoria (Bolz & Mellon 1947; Association of Vitamin Chemists 1966; A.O.A.C. 1975; Perkin-Elmer Corporation 1978). At the time when these analyses were done, a suitable dietary fibre method had not yet been standardized, and a crude fibre value is therefore given. In the EngUsh Food tables (Paul & Southgate 1978) a dietary fibre value of2,5% (fresh-mass basis) is given for mushrooms. Even this higher value, compared with the values we obtained, would make only a small difference in the calculated energy value of mushrooms. The amount of carbohydrate was calculated by difference [100 - (total moisture + fat + protein + crude fibre + ash)] (Triebold & Aurand 1963). Energy value was calculated in terms of kJ per 100 g (fresh-mass basis) by multiplying the percentage carbohydrate and protein by the factor 16,8 and percentage fat by the factor 37 ,8. It is assumed that all the carbohydrate calculated by difference is avaiJable as a source of energy (Triebold & Aurand 1963). The results of the analysis of the basidiocarps of the two fungal species are given in Table I. The total moisture content is high in both cases and there is little djfference between the nutrient coment of the two species. The vitamin C content of C. comatus appears to be higher than that of A. brunnescens. However, neither of the two species can be regarded as a good source of this vitamin. The vitamin Bt and In content of A. brunnescens
appears to be higher Lhan that of C. comarus. Both species can be regarded as a good source of nicotinic acid, provided it is not present in a bound form.
Coprinus comatus (MiiU. ex Fr.) S.F. Gray, also known as the shaggy ink cap, is a common mushroom in South Africa (Bottomley & Talbot 1953). It is an excellent edible species and has an agreeable flavour and aroma (Delmas 1978; Dickinson & Lucas 1979). These qualities partly inspired an investigation into methods of cultivation of the mushroom under controlled conditions (Winterboer 1981). In this note the nutrient content of C. comatus is given and is compared with that of the common cultivated mushroom Agaricus brunnescens Peck. Reports already published (Mcllvaine & Macadam 1973; Samajpati 1979) give data on the chemical composition of the mycelium and fruiting bodies, but the vitamin and mineral content and energy value of C. comatus have not yet been determined. Young, unexpanded basidiocarps of C. comatus which were cultivated at the University of Pretoria (Winterboer 1981), and a sample of A. brunnescens buttons (Strain: Sinden A6), supplied by Tongaat Mushrooms were used. Both species were cultivated under comparable conditions on similar substrates, consisting of standard mushroom compost prepared from horse manure and wheat straw (Vedder 1978). The mushrooms were freeze-dried and all determinations (except moisture content and vitamin C) were done on the dried, ground material. All results (the average of duplicate values) are expressed on a fresh-mass basis (Wehmeyer eta/. 1981). Vitamin C was determined on the fresh material. Nutrients were determined by the standardized methods used by the Division of Food Chemistry of
Table 1 The nutrient content of the basidiocarps of Coprinus comatus and Agaricus brunnescens Constituent (g/ IOOg Fresh mass) Moisture Fat Ash Crude protein (N x 4,38) Crude fibre Carbohydrate (By difference) (mg/ IOOg Fresh mass) Ca Mg Na K Cu Fe Zn
p Mn Vitamin 81 Vitamin 82 Nicotinic acid Vitamin C Energy value (kJ / IOOg Fresh mass)
C. comatus
A. brunnescens
90,8 0,1 0,8 2, 1 1,2 5,0
92,5 0,2 0,7 1.8 0,7 4,1
3,07 9,72 9,68 221,0 0,25 0,53 0,50 98,0 0,07 0,06 0,23
1,97 10,80 3,30 206,0 0,40 0,23 0,44 88,9 Not determined 0,11 0,38 3,80 3,0
3,55
6,8 123
107
84 The energy value and calcium, sodium, potassium, iron, phosphorus and fibre content of C. comatus is somewhat higher than that of A. brunnescens. The hjgher fibre content of C. comatus could be owing to the sturdy construction of its stem and shaggy, scaly cap as compared with the softer cap of A. brunnescens. These results indicate that C. comatus is nutritionally comparable with A. brunnescens. Although mushrooms are normally not regarded as an important source of any particular nutrient, they are a good source of minerals, comparable with most vegetables (Coetzee er a/. 1982). The promising figures of this preliminary investigation provide further motivation for continued research towards successful commercial cultivation of C. comatus.
Acknowledgements The helpful co-operation of Tongaat Mushrooms (Transvaal) Pty. Ltd. and financial support of the C.S.I. R. and the University of Pretoria are gratefully acknowledged. References A.O.A.C. 1975. Official Methods of Analysis. Association of Official Agricultural Chemists, Washington D.C. ASSOCIATION OF VITAM IN CHEM ISTS. 1966. Methods of Vitamin Assay. 3rd edn Wi ley, London. BOLZ. D.F. & MELLON, M.G. 1947. Determination of phosphorus, germanium, silicon and arsenic by the heteropoly blue method. Anal. Chem. 19: 873 - 877.
S.-Afr. Tydskr. Plamk., 1983, 2(1) BOTTOMLEY, A.M. & TALBOT. P.H.B. 1953. Algemeen eetbare en giftige sampioene in Suid-Afrika. Government Printer, Pretoria. COETZEE, J.C., EICKER, A. & WINTERBOER, A. 1982. The cu ltivation of South African edible fungi. Proceedings of the 6th Biennial SAFFOST congress, supplement to S.A. Food Review 9: 12-13. DELMAS, J. 1978. The potential cultivation of edible fungi. In: The biology and cultivation of edible mushrooms, eds Chang, S.T. & Hayes, W.A. p.699-724. Academic Press, New York. DICKINSON, C. & LUCAS, J. 1979. The Encyclopedia of Mushrooms. Oribis, London. MCILVAINE, C. & MACADAM, R.K. 1973. One Thousand American Fungi. Dover Publications, New York. PAUL, A.A. & SOUTHGATE, D.A.T. 1978. Melanee and Widdowson's The Composition of foods, 4th revised and extended edition of MRC special Report No. 297. Her Majesty's stationery office Elsevier/North Holland Biomedical Press, London. PERKIN-ELMER CORPORATION. 1978. Analytical methods for atomic absorption spectrophotometry, as supplied with the Perkin-Elmer instrument. model 30513. SAMAJPAT1, N. 1979. Nutritive value of some Indian edible mushrooms. Mush. Sci. 10 Part II: 695 - 703. TRIEBOLD, H.O. & AURAND, L.W. 1963. Food composition and analysis. D. V. Nostrand, New Jersey. VI:.DDER, P.J.C. 1978. Modern Mushroom Growing. Educabock, Culcmborg. WEHMEYER, A.S., COETZEE, J .C. & E1CKER, A. 1981. Nutrient content of Macrolepiota teyheri and Agaricus brunnescens. S. Afr. J. Sci. 77: 426 - 427. WJNTERBOER, A. 1981. 'n Studic van die wolhaarinkswam, Coprinus comarus (Miill. ex Fr.} S.P. Gray, in Suid-Afrika, M.Sc thesis. University of Pretoria.
A preliminary report on the nutrient content of Coprinus comatus Adriana Winterboer and A. Eicker• Department of Botany, University of Pretoria, Pretoria 0002, Republic of South Africa
A.S. Wehmeyer Division of Food Chemistry, National Food Research Institute, CSIR, P.O. Box 395, Pretoria 0001, Republic of South Africa •To whom correspondence should be addressed Accepted 6 September 1982
The nutrient content of Coprinus comatus (MOll. ex Fr.) S.F. Gray was determined and compared with that of Agaricus brunnescens Peck. It was found that the nutrient content of C. comatus is comparable with that of A. brunnescens. Die voedingstofinhoud van Coprinus comatus, (Mull. ex Fr.) S.F. Gray is bepaal en vergelyk met die van Agaricus brun· nescens Peck. Daar is gevind dat die voedingstofinhoud van C. comatus vergelykbaar is met die van A. brunnescens. Keywords: Agaricus brunnescens, Coprinus comatus, nutrient content
83 the National Food Research Institute of the C.S.I. R. in Pretoria (Bolz & Mellon 1947; Association of Vitamin Chemists 1966; A.O.A.C. 1975; Perkin-Elmer Corporation 1978). At the time when these analyses were done, a suitable dietary fibre method had not yet been standardized, and a crude fibre value is therefore given. In the EngUsh Food tables (Paul & Southgate 1978) a dietary fibre value of2,5% (fresh-mass basis) is given for mushrooms. Even this higher value, compared with the values we obtained, would make only a small difference in the calculated energy value of mushrooms. The amount of carbohydrate was calculated by difference [100 - (total moisture + fat + protein + crude fibre + ash)] (Triebold & Aurand 1963). Energy value was calculated in terms of kJ per 100 g (fresh-mass basis) by multiplying the percentage carbohydrate and protein by the factor 16,8 and percentage fat by the factor 37 ,8. It is assumed that all the carbohydrate calculated by difference is avaiJable as a source of energy (Triebold & Aurand 1963). The results of the analysis of the basidiocarps of the two fungal species are given in Table I. The total moisture content is high in both cases and there is little djfference between the nutrient coment of the two species. The vitamin C content of C. comatus appears to be higher than that of A. brunnescens. However, neither of the two species can be regarded as a good source of this vitamin. The vitamin Bt and In content of A. brunnescens
appears to be higher Lhan that of C. comarus. Both species can be regarded as a good source of nicotinic acid, provided it is not present in a bound form.
Coprinus comatus (MiiU. ex Fr.) S.F. Gray, also known as the shaggy ink cap, is a common mushroom in South Africa (Bottomley & Talbot 1953). It is an excellent edible species and has an agreeable flavour and aroma (Delmas 1978; Dickinson & Lucas 1979). These qualities partly inspired an investigation into methods of cultivation of the mushroom under controlled conditions (Winterboer 1981). In this note the nutrient content of C. comatus is given and is compared with that of the common cultivated mushroom Agaricus brunnescens Peck. Reports already published (Mcllvaine & Macadam 1973; Samajpati 1979) give data on the chemical composition of the mycelium and fruiting bodies, but the vitamin and mineral content and energy value of C. comatus have not yet been determined. Young, unexpanded basidiocarps of C. comatus which were cultivated at the University of Pretoria (Winterboer 1981), and a sample of A. brunnescens buttons (Strain: Sinden A6), supplied by Tongaat Mushrooms were used. Both species were cultivated under comparable conditions on similar substrates, consisting of standard mushroom compost prepared from horse manure and wheat straw (Vedder 1978). The mushrooms were freeze-dried and all determinations (except moisture content and vitamin C) were done on the dried, ground material. All results (the average of duplicate values) are expressed on a fresh-mass basis (Wehmeyer eta/. 1981). Vitamin C was determined on the fresh material. Nutrients were determined by the standardized methods used by the Division of Food Chemistry of
Table 1 The nutrient content of the basidiocarps of Coprinus comatus and Agaricus brunnescens Constituent (g/ IOOg Fresh mass) Moisture Fat Ash Crude protein (N x 4,38) Crude fibre Carbohydrate (By difference) (mg/ IOOg Fresh mass) Ca Mg Na K Cu Fe Zn
p Mn Vitamin 81 Vitamin 82 Nicotinic acid Vitamin C Energy value (kJ / IOOg Fresh mass)
C. comatus
A. brunnescens
90,8 0,1 0,8 2, 1 1,2 5,0
92,5 0,2 0,7 1.8 0,7 4,1
3,07 9,72 9,68 221,0 0,25 0,53 0,50 98,0 0,07 0,06 0,23
1,97 10,80 3,30 206,0 0,40 0,23 0,44 88,9 Not determined 0,11 0,38 3,80 3,0
3,55
6,8 123
107
84 The energy value and calcium, sodium, potassium, iron, phosphorus and fibre content of C. comatus is somewhat higher than that of A. brunnescens. The hjgher fibre content of C. comatus could be owing to the sturdy construction of its stem and shaggy, scaly cap as compared with the softer cap of A. brunnescens. These results indicate that C. comatus is nutritionally comparable with A. brunnescens. Although mushrooms are normally not regarded as an important source of any particular nutrient, they are a good source of minerals, comparable with most vegetables (Coetzee er a/. 1982). The promising figures of this preliminary investigation provide further motivation for continued research towards successful commercial cultivation of C. comatus.
Acknowledgements The helpful co-operation of Tongaat Mushrooms (Transvaal) Pty. Ltd. and financial support of the C.S.I. R. and the University of Pretoria are gratefully acknowledged. References A.O.A.C. 1975. Official Methods of Analysis. Association of Official Agricultural Chemists, Washington D.C. ASSOCIATION OF VITAM IN CHEM ISTS. 1966. Methods of Vitamin Assay. 3rd edn Wi ley, London. BOLZ. D.F. & MELLON, M.G. 1947. Determination of phosphorus, germanium, silicon and arsenic by the heteropoly blue method. Anal. Chem. 19: 873 - 877.
S.-Afr. Tydskr. Plamk., 1983, 2(1) BOTTOMLEY, A.M. & TALBOT. P.H.B. 1953. Algemeen eetbare en giftige sampioene in Suid-Afrika. Government Printer, Pretoria. COETZEE, J.C., EICKER, A. & WINTERBOER, A. 1982. The cu ltivation of South African edible fungi. Proceedings of the 6th Biennial SAFFOST congress, supplement to S.A. Food Review 9: 12-13. DELMAS, J. 1978. The potential cultivation of edible fungi. In: The biology and cultivation of edible mushrooms, eds Chang, S.T. & Hayes, W.A. p.699-724. Academic Press, New York. DICKINSON, C. & LUCAS, J. 1979. The Encyclopedia of Mushrooms. Oribis, London. MCILVAINE, C. & MACADAM, R.K. 1973. One Thousand American Fungi. Dover Publications, New York. PAUL, A.A. & SOUTHGATE, D.A.T. 1978. Melanee and Widdowson's The Composition of foods, 4th revised and extended edition of MRC special Report No. 297. Her Majesty's stationery office Elsevier/North Holland Biomedical Press, London. PERKIN-ELMER CORPORATION. 1978. Analytical methods for atomic absorption spectrophotometry, as supplied with the Perkin-Elmer instrument. model 30513. SAMAJPAT1, N. 1979. Nutritive value of some Indian edible mushrooms. Mush. Sci. 10 Part II: 695 - 703. TRIEBOLD, H.O. & AURAND, L.W. 1963. Food composition and analysis. D. V. Nostrand, New Jersey. VI:.DDER, P.J.C. 1978. Modern Mushroom Growing. Educabock, Culcmborg. WEHMEYER, A.S., COETZEE, J .C. & E1CKER, A. 1981. Nutrient content of Macrolepiota teyheri and Agaricus brunnescens. S. Afr. J. Sci. 77: 426 - 427. WJNTERBOER, A. 1981. 'n Studic van die wolhaarinkswam, Coprinus comarus (Miill. ex Fr.} S.P. Gray, in Suid-Afrika, M.Sc thesis. University of Pretoria.