The pH effects on cleaning of coconut milk deposits from batch pasteurizing process

Abstract

In this paper, the effects of pH on the cleaning of a model coconut milk foulant found in batchpasteurization process were studied. The model coconut milk foulants were soaked in NaOH solution at pHrange of 7-12. Swelling rate and swelling ratio increase slightly with pH at pH < 10 and increasing pH beyondpH 10 resulted in a significant rise of both swelling rate and swelling ratio. The pH effects observed here havebeen reported by literature in the case of milk foulants. Strength studies were performed on coconut milkfoulants under 3 conditions: (i) no soaking, (ii) soaking in distilled water (pH 7) and soaking in NaOH solution(pH 12) where maximum swelling ratio was observed. It was found that soaking had weakened the strength offoulants but the effect was not significant. The shear stress observed to remove the foulants under the 3conditions were in the range of 345-472 Pa.