Novel Processing Technologies for Fruits - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 70

Table 5.2. Effect of high pressure on tropical fruit products.

Fruit Products Process Condition Major Observation Reference

100-400 MPa, 20 ◦ C,
15 and 30 min

Mango puree No change in color, sugar profile; change

in rheological properties after HP
treatment

Ahmed et al. (2005)

200 MPa, -20 ◦ C Mango and peach This method maintained the original

tissue structure to a great extent

Otero et al. (2000)

Orange juice

500 MPa, 35 ◦ C, 5 min Lower loss of ascorbic acid compared to

conventional pasteurization (80 ◦ Cfor
30 sec)

Polydera et al. (2003)

400 MPa, 40 ◦ C, 1 min

A decrease in ascorbic acid and total
vitamin C just after HP treatment
compared with fresh juices

Sanchez-Moreno et al.
(2003)

600 MPa, 20 ◦ C, 1 min HPP of the juices reduced the microbial

load to nondetectable levels
immediately after processing

Bull et al. (2004)

600 MPa, 25 ◦ C, 15 min Guava puree No change in color, pectin cloud, and

ascorbic acid; no change in
water-soluble, oxalate-soluble, and
alkali-soluble pectin with original
flavor distribution and viscosity during
40 days' storage at 4 ◦ C

Yen and Lin (1996, 1999)

Kiwifruit 200-600 MPa,

10 ◦ -50 ◦ C

Pressures 400 MPa and temperature

50 ◦ C to accelerate POD enzyme
inactivation

> Fang et al. (2008)

Lychee 200-600 MPa,

20 ◦ -60 ◦ C, 10
or 20 min

HP treatment at 200 MPa caused a marked
increase in POD activity; the combined
effect of P/T on PPO activity was more
significant at longer treatment time

Phunchaisri and
Apichartsrangkoon
(2005)

300 MPa, 25 ◦ C, 5 min Yellow passion

fruit juice

HP treatment caused no significant
modifications in compounds
responsible for the yellow passion fruit
juice aroma, flavor, and consistency

Laboissiere et al. (2007)

50-700 MPa, 25 ◦ C,
10 min

Pineapple slice HPP reduced the sample hardness,

springiness, and chewiness, while it
had no significant effect on
cohesiveness of pineapple

Kingsly et al. (2009)

been properly exploited for tropical fruits since the process
is expensive and not available in the tropics. Selected stud-
ies on tropical fruits are in Table 5.2. Effects of HPP on
major quality parameters are discussed below.

specificity. Like temperature, enzymes could be affected
by pressure in different ways that can change their confor-
mity (Cheftel, 1992). Effects of high-pressure treatments
on enzymes can be either reversible or irreversible, and in-
activation relates to conformational changes in the protein
structure. Enzymatic reactions may be enhanced or inhib-
ited by pressure, depending on whether the volume change
associated with the reaction is positive or negative.

Enzymes
Enzymes are a special group of protein molecules and
are characterized by their tremendous catalytic power and