Chestnut Varieties Research Articles

Changes in the free and total amino acid composition of ripening chestnut seeds

The distribution of free and protein amino acids during seed development is described for three chestnut varieties. Asparagine accumulation was shown to correlate with protein biosynthesis. Accumulation of free amino acids takes place before that of proteins in ripening seeds. A temporary decrease was generally accompanied by protein biosynthesis and followed by final accumulation of both protein and free amino acids.

Comparison between the chestnut gall wasp (Dryocosmus kuriphilus YASUMATSU) on the susceptible chestnut variety and those on the resistant variety

Comparison between the chestnut gall wasp (<i>Dryocosmus kuriphilus</i> YASUMATSU) on the susceptible chestnut variety and those on the resistant variety

Studies on chestnut varieties suitable for making marrons glacés (glace chestnuts)

1. For the purpose of selecting suitable varieties for marrons glacés, twenty five varieties were tested in laboratory and cannery during the three years from 1947 to 1949. 2. The ratio of outer skin and inside peel to the whole weight of nuts showed considerable difference among these varieties, and consequently there were much variations in the percentage of edible portion, ‘Rihei’ was the highest in edible portion (80%), while ‘Konishiki’ the lowest (64.9%). 3. The results of analytical investigations sho-wed that moisture content of chestnut flesh was very different between each varieties but it was about 60% in most cases. Contents of crude starch in nut flesh ranged from 27 to 40%. As to sugar contents, there was more cane-sugar content than reducing sugar in most varieties, lexcepting ‘Chuwase’ and ‘Nakate Tamba’ 4. Large nut varieties tested were not available for marrons glacés; while among middle nut varieties ‘Chuwase’, Akachu' and ‘Obuse No. 2’ were suitable for this purpose. 5. Products made of Chinese varieties (Castanets mollissima BLUME) were somewhat harder in texture and smaller in size than those of Ja-panese varieties (C. crenata SIEB. et ZUCC.). Accordingly the latter seems to be more suitable for marrons glacés than the former. 6. For making marrons glacés of high quality it is primarily important to use perfectly mature nuts and to cook them as soon as possible after harvesting. Immature nuts are not suitable for this purpose and long stored nuts give dark color on products. 7. Winding threads around the peeled nuts is remarkably effective in preventing the cracking that occurs in the proceessing, and it may be commercially advisable method in large nut varieties in spite of troublesome work.