Agriculture Reference
In-Depth Information
wifruit nectar from frozen kiwifruit concentrate (El-Zalaki
and Luh, 1981), and Kiwi Crush (Vital Food Processors
Ltd, Manukau City, Auckland, New Zealand), as shown in
Fig. 25.6.
Kiwifruits
(>80% ripeness, Brix >8%)
Cleaning
INDIGENOUS PROCESSED PRODUCTS AND
BY-PRODUCT UTILIZATION
Several products and food applications which are unique
to New Zealand and China are presented in Table 25.5
and Figs. 25.6, 25.7, and 25.8. Kiwifruit wastes (pomace
including skin) can account for up to 30% of the total
kiwifruit crop (Schieber et al., 2001) and are normally dis-
carded due to the unpleasant sensory attributes such as
intrinsic bitterness (Amos, 2007). However, several novel
uses for kiwifruit waste have been proposed, as shown in
Table 25.6.
Extraction
Filtration (sieve
diameter: 0.3 mm)
Sugar solution,
flavorings,
stabilizers
1 st Grinding
Heating 45-50 o C
Add pectinase
(15-20 mg/kg)
NUTRITIONAL PROFILE AND HEALTH
BENEFITS
Based on the USDA and NZ database, the nutrient values of
green and yellow-fleshed kiwifruits are quite similar, with
slight differences in the content of total sugar, vitamin C,
and selenium (Table 25.7). Kiwifruits are widely known
as healthy fruits due to their high content in antioxidants,
especially vitamin C. Compared to other horticultural prod-
ucts, kiwifruits have a very high dosage of vitamin C. One
kiwifruit (with total fresh weight of 100 g) contains ap-
proximately 60-100 mg of vitamin C, which almost fulfills
the recommended daily allowance (RDA) for adults and
more than the RDA for children and youth. Kiwifruits are
also rich in other antioxidants such as folates (Indrawati
et al., 2004; Lu et al., 2009), lutein, zeaxanthin, cryotoxan-
thin and
2 nd Grinding; particle
size <5um
Homogenization
Vacuum degassing
(90.6-93.3 kPa, 30 min.)
UHT (121 o C, 5-10s)
Sterilization of
bottles; 85-95 o C
for 35 min.
Bottling (>80 o C)
β
-carotene (Nishiyama et al., 2007), and pheno-
lic compounds (Dawes and Kenne, 1999). Therefore, the
consumption of these kiwifruits increases the antioxidative
status in humans, which provides some protection against
some diseases such as cardiovascular disease (Chang and
Liu, 2009). Using mice as animal model system, high con-
sumption of kiwifruits stimulated the immunity response
in the gut (Hunter et al., 2008). Kiwifruit has cytotoxic and
antibacterial activities (Kawase et al., 2001).
Consumption of kiwifruits provides health benefits to the
human guts. Kiwifruit pectin (Parkar et al., 2010) and zy-
actinase (complex compounds consisting of protease, fiber,
pectin, and fructo-oligosaccharides) (Weir et al., 2008)
shows probiotic effects. Furthermore, kiwifruits can relieve
the constipation problem (laxative effect) by increasing the
transit time (Rush et al., 2002; Chan et al., 2007).
Figure 25.5. Diagram depicts the processing steps
for the production of kiwifruit juice (sources:
Adapted from Huang et al., 2007; Pan, 1993).
1996) is as follows:
Kiwifruit
Hair removal
Wash-
ing
Soft pulping
Cooling of pulp
Addition of
sweetening/other agents
Juice extraction. The disad-
vantages of this type of processing are that kiwifruit juice
concentrates undergo rapid nonenzymic browning and haze
formation during storage (Ferguson and Stanley, 2003).
Fig. 25.5 shows a more representative kiwifruit juice pro-
duction flowchart, adapted from Pan (1993) and Huang
et al. (2007). Some examples of the juice-type kiwifruit
products are blended juices (Cassano et al., 2006), ki-
Search WWH ::




Custom Search