Many varieties of dried Shiitake mushroom (Lentinus edodes Sing.) are commercially marketed in Japan. They are graded according to size, thickness, color, shape of the caps and the degree of dryness.
We investigated the quantitative difference of 5^'-nucleotides and free amino acids, which are responsible for the taste, in various varieties of dried Shiitake mushroom. Eleven different varieties of dried mushroom under the name of Haruko, which is harvested exclusively in spring, were collected during 1970-1972 and 1974 from Ohita-Pref., Kyushu, Japan. The amount of 5^'-nucleotides in boiled water extracts and the amino acid composition in 70% ethanol extracts, were determined by ion exchange chromatographic methods and amino acid analyzer, respectively.
The amounts of 5^'-AMP, 5^'-UMP and 5^'-GMP were 63-116 mg%, 51-116 mg% and 33-128 mg% respectively. No quantitative differences of 5^'-GMP were seen among the mushrooms except Kuroko having significantly low content of 5^'-GMP. Glutamic acid 145-468 mg% was the highest amount attained among the eleven varieties examined, followed by threonine+serine (fraction containing glutamine and asparagine) 129-414 mg%, lysine (containing unknown ninhydrin positive fraction) 101-232 mg%, alanine 81-181 mg%, aspartic acid 46-103 mg% and arginine 55-87 mg%. The other amino acids were less than 50 mg%. There were no significant differences in the amount of glutamic acid among different varieties of the mushroom except Kuroko. The similarity index for amino acid pattern calculated by Tamura's methods showed close similarities among the ten varities of mushroom except Kuroko.

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In order to elucidate the reaction of autoxidizing fatty acid esters on proteins, the experiments were carried out by using various aliphatic amines, aromatic amines and other compounds.
In the cases of aliphatic or aromatic amines, the reaction proceeded rapidly from initial 0.5 to 2 hours.
As the time proceeded, the peroxide value of autoxidizing fatty acid esters gradually decreased. However, no particular change was noticed, when aliphatic hydrocarbons, aromatic hydrocarbons or aromatic nitro compounds were used, just like in the case of control experiment.
The above results substantially proved that the reaction of autoxidizing fatty acid esters on amine occured at the site where amino groups, imino groups or nitrogen molecule are present.

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Intrinsic viscosities of glutenins contained in various wheat flours were determined in 6.5 M guanidine hydrochloride to investigate the correlation between the property of flour and the size and shape of glutenin molecules. The ratios of the contents of gliadin and glutenin determined by gel filtration were slightly different among the flours examined and the mean ratio was 41 : 59. No correlation was observed between the ratios and the properties of the flours. The intrinsic viscosity of glutenin was obtained by calculation from the intrinsic viscosities of gluten and gliadin. The intrinsic viscosity of gluten was determined to be about 0.7 dl/g with some differences depending on the flours, but that of gliadin gave nearly the same value of 0.2 dl/g for all the flours used. The intrinsic viscosities of glutenin calculated were in the range of 0.95 to 1.14 dl/g and were somewhat different among the flours. However, the expected correlation between the intrinsic viscosity of glutenin and the property of flour was not found. Therefore, there must be other factors affecting the quality of protein more strongly than the size and shape of glutenin.

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Two natural pigments, orange and violet, produced by Monascus anka H-26 were extracted.
Structures of these materials were examined by the measurement of ultra violet, visible, infrared, nuclear magnetic resonance, and mass spectra along with elementary analysis and melting point.
From these results it was found that orange dye is monascorubrin and violet dye is monascorubramine.

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Quantitative analyses of eritadenine, a hypocholesterolemic principle of “shii-ta-ke” (Lentinus edodes), in several species of edible mushrooms were achievable by the following procedures. The methanolic extracts obtained from less than 10g of the mushroom were defatted and the residue was fractionated on a Dowex 50-X8 column (1.7 X 20 cm) with 1_N hydrochloric acid. The fraction containing eritadenine was then chromatographed on a Dowex 1-X8 column (0.8 X 35 cm) with 0.005_N formic acid and the eritadenine contents in the eluate were determined by measuring the UV absorption at 260 nm.
Species of mushrooms subjected to analyses are as follows; Lentinus edodes, Agaricus bisporus, Lyophyllum aggregatum, Auricularia auricula judae, Flammulina velutipes, and Pholiota nameko. The result indicated that only “shii-ta-ke” mush room contained eritadenine at relatively high levels : 60-70 mg% in the cap and 40mg% in the stem. No other species contained eritadenine in a detectable amount except A. bisporus in which a trace amount of eritadenine (0.7 mg%) was present.

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Rapid and accurate methods for measuring calcium in laying hen plasma and shell gland fluid by atomic absorption spectroscopy have been examined in the present work.
The established procedure was briefly given as follow : Into a 25ml volumetric flask were pipetted 0.5ml of plasma or 1ml of shell gland fluid, and 2.5ml of strontium chloride solution (40, 000 ppm Sr). The mixture was made up to 25ml with distilled water. Using the dilute fluid prepared as above, the calcium content of plasma or shell gland fluid was determined with a nitrogen oxide-acetylene flame by atomic absorption spectroscopy.
Thus, calcium in laying hen plasma and shell gland fluid could be determined on directly dilute samples without prior removal of any constituents. Recoveries of calcium added were satisfactory; values recovered were 100-107% for plasma and 97-100% for shell gland fluid.

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To promote the use of the spent hen meat as a cheeper meat source, the difference of the changes in the tenderness, water holding capacity and protein extractability between broiler and spent hen muscles during storage was investigated.
The pass of two stages, rigor mortis and thaw rigor as measured by penetrometer, was observed clearly in the broiler muscle compared with the spent hen muscle, and maximal rigor was observed within 2-4 hr after slaughter. The difference in the tenderness between broiler and spent hen muscles was also detected from the penetrometer readings.
The water holding capacity of the raw broiler and spent hen meats decreased rapidly after death, reached to minimum at about 6 hr after death and was recovered with the progress of the storage. The same tendency was observed in the cooked broiler meat, but the decrease in the water holding capacity with the progress of rigor mortis was not observed in the cooked spent hen meat. The degree of the changes in the water holding capacity of the spent hen meat was less than that of the broiler meat, irrespective of cooking or uncooking.
The amounts of extracted sarcoplasmic and myofibrillar proteins from the broiler muscle decreased till about 6 hr after death and after that, increased with the progress of the storage. On the other hand, the extractability of the sarcoplasmic and myofibrillar proteins from thespent hen muscle increased gradually after death, and the decrease in the extractability as observed in the broiler muscle was not observed.

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POV method was modified to the convenient way to determine the deterioration degree of lipids contained in oil processed foods. A piece of food is immersed into POV reagent solution and dried with a hair drier. Then it is put into water, and blue color appears.

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