Removal of the bitterness in Natsudaidai fruits can be achieved to some extent by means of enzymatic hydrolysis of naringin which is principal ingredient of bitterness. At present, this method is appreciated as to be most effective for debittering but it leaves something to be studied still more and the bitterness of canned fruits has not been removed sufficiently as yet. According to pre-experiment, this defect of enzymatic debittering seemed to be caused by imperfection of contact between enzym and substrate. So in this experiment, in order to promote the permeation of naringinase into fruits texture, surface active agent (Tween 80) was added in naringinase solution and the effect of it for debittering was studied. The results obtained are summarized as follows :
1. So far as the concentratron of Tween 80 was more than 0.03%, a good effect of surface active agent was recognized for debittering but when fruits were dipped in enzym solution contained Tween 80 before packing it was observed that fruits shape had tendency to be broken even if the concentration of Tween 80 was lower limit of availability such as 0.03%.
2. When surface active agent was added in syrup together with thermostable naringinase on canning process broken fruits was scarcely recognized only but debittering effect.
From mentioned above, most effective employment of surface active agent for debittering of canned Natsudaidai fruits seemed that it had to be added in syrup together with thermostable naringinase and the optimum concentration of it was 0.03-0.05%.