FOODS ANIMAL PRODUCTION. 



377 



The variation in composition of different mushrooms is discussed. 

 Among the bases found in the ash were potassium, sodium, and some- 

 times calcium. Iron was always present. Sulphuric and phosphoric 

 acids predominated and chlorin was occasionally found. 



The dry material was first digested with pepsin and hydrochloric 

 acid and afterwards with a solution of dog pancreas, a little chloroform 

 being added to prevent fermentation and also thermolized extract of 

 dry pancreas powder. The undigested residue was eventually removed 

 and dried and the nitrogen in it determined. 



The total digestible nitrogen was determined by subtracting the 

 nitrogen in the undigested (insoluble) residue from the total nitrogen 

 of the original substance. 



The nitrogen in the undigested residue was also subtracted from 

 the total albuminoid nitrogen, the difference multiplied by 0.25, in 

 the author's opinion, representing the true digestible protein in the 

 mushrooms 



The results of the digestion experiments are summarized as follows: 



Coefficients of digestibility of various species of edible fungi. 



Total un- Kitrogen 



digesti- in unai- 



blemate- gestible 



rial. material. 



Proteid nitrogen. 



In origi- 

 nal sub- 



Per cent. Per cent. 



Shaggy mushroom 26.21 



Inky coprinus 28. 16 



Common morel 49. 42 



Oyster mushroom 59. 43 



Sulphury polyporus 55.00 



Clitocybe m uliiceps 37. 57 



Hypholoma eandolleanum 31. 98 



4.21 

 2.79 

 4. ID 

 1.39 

 i.05 

 1.96 

 3.63 



Per cent. 

 5.79 

 4.68 

 4.66 

 2. 40 

 3.29 

 5.36 

 4.28 



Indi- 

 gestible. 



Per cent. 

 1.10 



.78 

 2.05 

 .82 

 .58 

 .73 

 1.16 



Digesti- 

 ble. 



Albuminoid ni- 

 trogen. 



In origi- 

 nal sub- 

 stance. 



Percent. Percent 



4.69 

 3.911 

 2.61 

 1.58 

 2.71 

 4.63 

 3.12 



1.92 



3.49 

 1.13 

 2.23 

 1.98 

 2.49 



Digesti- 

 ble. 



True 

 digesti- 

 ble pro- 

 tein. 



Percent. Percent. 

 . 82 5. 12 



1.44 

 .31 

 1.65 

 1.25 

 1.33 



9.00 

 1.94 

 10.31 

 7.81 

 8.31 



The fact is pointed out that considering the high water content and 

 the comparatively small amount of digestible protein which they con- 

 tain, mushrooms do not have a high food value. In this respect they 

 resemble ordinary vegetables and the term "vegetable beefsteak" which 

 is often applied to them is very erroneous. 



"The carbohydrate content of the fungi is relatively high; but until 

 more is known regarding the nature and digestibility of the carbohy- 

 drate constituents of various vegetable foods, it will be useless to draw 

 comparisons. As dietetic accessories the edible fungi may play an 

 important part; but investigation has demonstrated that they can not 

 be ranked with the essential foods.' 1 



Chemical composition and digestibility of edible fungi, M. 

 STAHL-ScireoDER (SeUJe. Khoz. i Lyesov., 184 {1897), Feb., pp. 137- 

 446). — This investigation includes analyses of several varieties of edible 

 fungi, detailed analyses of the ash constituents, and digestion experi- 

 ments with rabbits and by artificial digestion. 



