Meanwhile,
phosphate buffer acts as a buffering medium to help regulate catalytic
activity of enzymes (Good et al., 1966; Kuntz & Kauzmann, 1974). The
added phosphate buffer was then further used immediately as the extraction
buffer (refer Section 2.4) to extract enzymes from the carrot
mash or piece and to recuperate the endogenous enzymes being
released to the buffer during PEF processing. The weight of both carrots
(mash or piece) and phosphate buffer was recorded; with overall total
weight averaged between 320 to 350 g added for each PEF treatment
condition.The resulting total weight (not more than 350 g) filled up
the entire PEF chamber to allow uniform delivery of electric field
strength across two electrodes while avoiding the presence of air
space during PEF treatment. The effectiveness of PEF for enzyme inactivation
between carrot mash and carrot piece was compared through
standardising the ratio of carrot and phosphate buffer (with ratio of
1:2.5) added to the PEF chamber. Each PEF treatment condition was
independently conducted in triplicate.