The researchers set four objectives.
Figure 2: Sensory properties of
pomegranate
S ensory properties of pomegranate ‘Acco’, ‘Herskowitz’
Figure 2: Sensory properties of pomegranate
and ‘Wonderful’ after six weeks of storage at 5°C and five
Sensory properties of pomegranate ‘Acco’, ‘Herskowitz’ and ‘Wonderful’
days after
of six
shelf
at 20°C.
The
shows
averaged
weeks life
of storage
at 5°C
and radar
five days plot
of shelf
life at 20°C.
The
sensory
scores
(scale
= 0–5;
n = scores
8). (scale = 0–5; n = 8).
radar
plot shows
averaged
sensory
n Harvest 1
n Harvest 2
n Harvest 3
n Harvest 4 n Harvest 5
ACCO
Sweet
Acceptability
Sour
Flavour
1
Appearance
2
3
4
5
Off-flavour
Astringency
Aril colour
Crispness
Hardness
Juiciness
Grittiness
HERSKOWITZ
Sweet
Acceptability
Sour
Flavour
1
Appearance
2
3
4
5
Off-flavour
Astringency
Aril colour
Crispness
Hardness
Juiciness
Grittiness
WONDERFUL
Sweet
Acceptability
Sour
Flavour
1
Appearance
Aril colour
2
3
4
5
Off-flavour
Astringency
Crispness
Hardness
Juiciness
Grittiness
Objective 1: Develop a predictive optimum
maturity index for commercially grown
pomegranate cultivars in South Africa.
Key results:
• All three pomegranate fruit cultivars
followed a linear growth pattern over
the study period and characteristic fruit
shapes developed around 110 DAFB for all
three cultivars.
• Fruit skin colour was not a good indicator
of aril colour during fruit growth and
maturation, and sugar concentration (TSS)
fluctuated, particularly for ‘Herskowitz’ and
‘Acco’.
• All cultivars were susceptible to a wide
range of pre-harvest fruit disorders
and defects, but cracking affected only
‘Herskowitz’. ‘Herskowitz’ was also the
most susceptible to crown rot, with higher
incidence occurring later during harvest.
• Based on the combination of data on
fruit physico-chemical properties,
sensory analysis and incidence of storage
disorders, the optimum harvest maturity
coincided with 123 to 132 DAFB for
‘Acco’, 133 to 137 DAFB for ‘Herskowitz’
and later than 134 DAFB for ‘Wonderful’
pomegranates.
Objective 2: Characterise storage potential
and shelf life for commercial pomegranate
cultivars in consideration of the long supply
chains.
The greatest determining factor of storage
practices is susceptibility to post-harvest
disorders. Fruit with retained flavour is of no
use if it exhibits disorders such as crown rot,
given the risk that such disorders may spread
easily from infected to uninfected fruit.
Key results:
• Based on observations of post-harvest
disorder development, the first three
harvests of ‘Acco’ and the first two
harvests of ‘Herskowitz’ would be ideal,
as no crown rot incidence was observed.
• The first four harvests of ‘Wonderful’
exhibited mild crown rot in the sixth
week of storage although the incidence
was lower than in ‘Acco’ or ‘Herskowitz’.
• ‘Herskowitz’ was most susceptible to
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