1984 Volume 53 Issue 2 Pages 194-201
In order to establish a long-term storage procedure for chestnuts, both precooling, by room cooling, pressure cooling and vacuum cooling, and cold-storage with polyethylene pouches were investigated. Results obtained were as follows:
1. Vacuum cooling gave the fastest cooling rate, followed by pressure cooling and by room cooling. Vacuum cooling, however, gave rise to white spots on the shell of chestnuts which was considered to be an undesirable selling factor. Of the three precooling treatments mentioned above, pressure cooling was thought to be the best.
2. The weight losses during cooling were 1.6% for pressure cooling and 2.8% for vacuum cooling. In the latter case, the loss was approximately equal to the result calculated from the temperature reduction, assuming that almost all of the latent heat of vaporization came from the product.
3. The extent of mold growing on the shell or scar of the stored chestnuts increased with increasing storage temperature and storage period. Almost all of the chestnuts which were stored at 10°C for 4 months or at 5°C for 6 months were spoiled.
4. To evaluate an elastic modulus of chestnut flesh, cylindrical specimens were cut out from chestnuts along with long and short axis parallel to the seed scar. In chestnuts stored at 1°C, elastic modulus of the long axis flesh changed with the storage period.
5. The sucrose content of the chestnuts stored at 1, 5 and 10°C increased rapidly during the first month, particularly at 1°C. Conversely, the starch content of the chestnuts decreased during the above period.
6. The LL size chestnuts were more suitable for storage than L size ones. Since both the respiration rate and the weight loss of these chestnuts were lower than in L size.
7. The shelf life of the LL size chestnuts was 3 months at 1°C, 2 months at 5°C and 1 month at 10°C.
