Abstract
In order to examine the effects of pretreatments on the reaction between gelatin and κ-carrageenan, the gelatin samples (3%) treated in both acid and alkali conditions were mixed with κ-carrageenan of various concentratian of 0.25%-1.75% and the characteristic properties of resultant sol and gel solutions were examined.
The results obtained were as follows.
1) The pH of the mixed sol with κ-carrageenan were higher in alkali treated gelatin than the Ip of native gelatin but lower in acid treated one.
2) When 0.25%-0.75% of κ-arrageenan solution was added with the acid treated gelatin, precipitates resulted and gelatin with lower molecular weight were detected in supernatant.
3) The hardness of gels from the mixed solution of alkali treated gelatin with κ-carrageenan were higher than those from either alkali treated gelatin or κ-carrageenan itself.
4) The gel formation from the mixed solution of alkali treated gelatin and -carrageenan was observed in 1% of κ-carrageenan, and the hardness were almost the same to that from κ-carrageenan alone. The hardness of gels were remarkably increased in the concentrations of more than 1.25% of κ-carrageenan and the precipitates were also formed in these concentrations.
