MUSHROOMS 5 



Hutchings and Peterson (9) was followed, using Lactobacillus arabinosus 17-5 

 as the test organism. The amino acid content of mushrooms on a fresh weight 

 basis as determined above was found to be as follows: 



Mg. per 100 grams 

 Amino acid fresh weight basis 



1-arginine - 203.17 



dl-isoleucine 458.85 



1-leucine 242.02 



dl-methionine 144.37 



1-tryptophane 5.07 



dl-valine _.. -... 326.02 



Although the results of the animal feeding tests indicate the presence of all of 

 the essential amino acids in mushroom protein, taken by themselves they may 

 be open to question. However, the chemical and microbiological tests bear out 

 the fact that these amino acids are present, even though in small amounts in 

 some cases. Positive chemical tests were not obtained for valine, isoleucine, and 

 methionine but their presence was demonstrated by the microbiological tests. 



It was concluded that fresh mushrooms {Agaricus campestris) contain approx- 

 imately 2.67 percent of protein. While they are not comparable with such foods 

 as meat and fish as a source of protein, they do compare favorably with many 

 fresh vegetables in this respect. 



Carbohydrate 



But little information has been found on the carbohydrate content of mush- 

 rooms {Agaricus campestris). Inagaki (10) found mannitol present in wild mush- 

 rooms {Agaricus campestris) in concentrations of 0.93 percent of the dry weight 

 of the cap and 0.17 percent of the stipe. Nickerson and Rettew (17) isolated 

 and identified mannitol from the same variety. They reported an average of 

 5.5 percent of the dry weight of the immature button stage and 9.9 percent of 

 the dry weight of the mature open stage recovered as mannitol. Other carbo- 

 hydrates and poly-alcohols such as trehalose, glucose, glycogen, sorbitol, pentoses, 

 and cellulose have been reported present in other varieties. 



McConnell and Esselen (13) have reported on the carbohydrate content of 

 mushrooms {Agaricus campestris) grown in Massachusetts by a commercial 

 grower. Good quality, large, fresh mushrooms in the closed stage were selected, 

 sliced into quarter-inch pieces, and dried. The dried product was ground in a 

 Wiley mill to pass through a 60-mesh screen. The A. O. A. C. (2) method tor 

 analysis of sugars in plants was followed. Qualitative tests were made for the 

 presence of the various carbohydrates. By means of these tests many carbo- 

 hydrates were found to be absent in the mushroom. Quantitative tests were 

 then made for those carbohydrates whose presence might have accounted for 

 the positive qualitative tests. The results are shown in table 1. 



The reported mannitol content is, in general, in agreement with the amount 

 found in this same variety by Nickerson and Rettew (17) but is much higher 

 than that reported by Inagaki (10) for wild mushrooms. The carbohydrates 

 present in greatest quantities were mannitol, hemicellulose, glycogen, and reduc- 

 ing sugars, which together accounted for 2.73 percent of the weight of the fresh 

 mushrooms. 



