Banana - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 139

air temperature, and velocity. No effect was observed on the
color of the dried banana, but some effects were observed
with respect to porosity and apparent volume.
Unripe banana is rich in starch, and that starch has a
great amount of resistant starch (Zhang et al., 2012), includ-
ing some resistant starch of type II (Faisant et al., 1995).
The effect of drying conditions was evaluated on the resis-
tant starch content in banana ( Musa acuminata subgroup
Cavendish). Unripe banana flour produced from fruits char-
acterized at first stage of ripening presented a high resistant
starch level, from 40.9 to 58.5 g/100 g on dry basis. Resis-
tant starch content was significantly influenced by air ve-
locity during the drying process. Unripe banana flour dried
at higher air velocities presented higher resistant starch
amounts, especially at air temperatures that were lower than
the starch gelatinization temperature (Tribess et al., 2009).
The effect of air temperature on texture (Boudhrioua
et al., 2002) and aromatic components (Boudhrioua et al.,
2003), the method of drying on color (Krokida et al.,
2001; Baini and Langrish, 2009), and changes in the physi-
cal properties due to applying high-temperature short-time
(HTST) pulse during air drying (Hofsetz et al., 2007) on
banana fruit have been studied previously.
A simple solar drying system suitable for different agri-
cultural fresh commodities was evaluated to dry banana
pulp. The drying system mechanism was flexible; it was
constructed from cheap and available materials (Hassanain,
2009). A hybrid solar dryer was designed and constructed
using direct solar energy and a heat exchanger for drying of
ripe banana slices. The dryer was operated during normal
sunny days as a solar dryer and during cloudy days as a
hybrid solar dryer. Recycling about 65% of the drying air
in the solar dryer and exhausting a small amount of it out-
side the dryer raised the efficiency of the solar dryer (Amer
et al., 2010).
Spray drying is one of the methods used to dehydrate
foods. Banana pulp was spray dried using maltodextrin
and rubber acacia to maximize solids ( ◦ Brix) and minimize
the viscosity. The maltodextrin has a significant effect for
both parameters. It is necessary to find a balance between
the maximum ◦ Brix and minimum viscosity for the drying
process. Low viscosity allows a better flow of the mixture
in the spray system (disk or diffusion), and a high concen-
tration of total solids increase the performance of the final
product (Lopez et al., 2009).

worked manually until the juice is released. This artisan
process was improved; by replacing grass with polyethy-
lene strips, the mixture pulp-polyethylene is worked into
a dough mixer until the juice appears. Juice yields from
54% to 80% (w/w of peeled fruit pulp) have been ob-
tained, depending on the banana variety (Kyamuhangire
et al., 2002). Another process to extract banana juice in-
cludes treatment with hot water. This method is often used
to maximize juice yield, color, and flavor (McLellan, 1996).
The fruit is peeled, sliced, and introduced into boiling wa-
ter. The heat breaks down the pulp for extraction of juice
and simultaneously inactivates enzymes in the pulp (Luh
and Woodroof, 1975). Thereafter the extraction method of
banana juice is optimized using response surface method-
ology. The authors concluded that the different conditions
(extraction time and temperature) for hot water extraction
of banana juice showed that all these variables markedly
affect the juice yield, total soluble solids, aroma, and taste
of the banana juice extract (Lee et al., 2007).
Raw banana juice is turbid, viscous, and gray in color.
The turbidity and viscosity of raw banana juice are caused
mainly by starch and nonstarch polysaccharides (pectin).
Enzymatic pretreatment that degrades the pectin has been
investigated to clarify banana juice (Kyamuhangire et al.,
2002; Lee et al., 2006a).
Development of new products is a priority area of the
food industry. The use of by-products and surplus of agri-
culture products can be feasible to obtain food products
at low cost. Koffi et al. (2005) evaluated the storage sta-
bility and sensorial characteristics of a beverage made by
blending whey and banana juice. The product was sour,
sweet, and smooth, and the classic banana flavor was not
detected. The development and shelf life of whey-based
banana herbal beverages were evaluated. With the different
components present in banana juice, whey can improve
nutritional and sensorial characteristics of the beverage
(Yadav et al., 2010).
The nutraceutical food is an important area of food in-
dustry. Recently, banana juice was fortified with inulin and
oligofructose. These carbohydrates did not significantly
affect the physicochemical, microbiological, and sensory
characteristics of the clarified banana juice over a period of
8 weeks (Yousaf et al., 2010).

Canning
Canning is typically not a method of choice for commer-
cial processing of bananas. Any canning of banana reported
in the literature has been for experimental purposes only.
Three banana ( Musa spp.) varieties, 'Poovan,' 'Rasthali,'
and 'Red Banana,' were peeled, sliced to 10 mm thickness,

Juice, concentrate, and juice blends
Traditionally, banana juice is extracted using a technology
based on physically working the pulp, and this process has
been mechanised. The banana pulp is mixed with grass and