Untersuchungen zur Wasseraufnahme brechender und nichtbrechender Kotyledonen von Bohnensamen (Phaseolus vulgaris L.) )

Abstract

Summary Theoretical considerations about the origin and the mechanism of the tensions causing cotyledonal cracking, and also the statements of M c C ollum and Y amoto seeing a relation between velocity of swelling and cracking of bean cotyledons were the inducement to many experiments on characterising the event of swelling in cracking and non-cracking bean cotyledons. 1. Having an initial water-content of 11 % the non-cracking cotyledons take up more water than the cracking ones. 2. The velocity of swelling of non-cracking and cracking cotyledons with a water-content of 11 % increases raising the water-content. The velocity of swelling reaches a maximum at various water-contents dependent on the kind of the two bean sorts. After a following increase of the water-Content the velocity of swelling decreases again. 3. Increasing the water-content the velocity of swelling of cracking cotyledons grows absolutely and relatively more than that of the non-cracking ones. 4. The occurrence of cracking decreases continually by increasing the initial water-content of the cotyledons. At an initial water-content of 21 % does not occur any cotyledonal cracking during the soaking process. 5. Increasing the water-content from 11 % to 21 % the humidity distributes completely in the cotyledons causing changes in the manner of cotyledonal cracking. 6. After damping them the cotyledons crack earlier in the beginning hours of a new soaking process than the non damped cotyledons. With longer periods of storage the distances of the cross ruptures become larger to the cotyledonal ends. After damping 10 hours cross ruptures occur only in the middle of the cotyledo. After moisturing 22 hours any ruptures do not occur during the soaking process.