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Cassava foam, another form in which cassava may potentially be used as food, was produced from the pulp of
yellow-flesh and white-flesh cassava varieties by whipping with foaming agent (20 %w/w glycerol monostearate
colloid, GMS) and stabilizer (sodium carboxymethyl cellulose, NaCMC). Cassava foaming was optimized for
concentration of foaming agent, stabilizer and whipping time. Using Box-Behnken experimental design, two
responses were measured: foam expansion (FE, %) and foam density (FD, g/mL). White-flesh cassava pulp required
14.97% GMS, 0.51% NaCMC and 2.07 min to give a foam of 52.63% expansion and density of 0.75 g/mL.
Yellow-flesh cassava pulp required 14.29% GMS, 0.6% NaCMC and 2 min to yield a foam of 48.25% expansion
and density of 0.76 g/mL. Predicted optimal FE and FD were 54.9% and 0.73 g/mL for white-flesh cassava foam,
and 49.86% and 0.73 g/mL for yellow-flesh cassava foam, respectively, and are close to validated values. The
optimal foams were quite stable after 4 h at 25 ± 2 °C, with low volume collapse of 1.79% and 1.26% for white
and yellow cassava foams, respectively. The optimal cassava foams were dried into foam powder. There was
significant difference in color values (L*, a*, b*, C*, E*, H*, % W, Eyellow white) and total carotenoids content of
pulp, optimal foam, and powder of both varieties. Microstructure analysis of the optimal foams revealed round
air bubbles and positive skewed distribution of bubble sizes. Foaming and drying significantly reduced total
cyanogenic potential in cassava, and may be considered as processing operations capable of reducing cyanogenic
potential in cassava considerably.

In recent times, the cultivation, processing and
consumption of biofortified yellow-flesh cassava is of
significant interest to breeders and food processors due to
its relatively high pro-vitamin-A content, compared to the
conventional white-flesh cassava. In light of this, osmotic
dehydration (OD) kinetics of a recently released biofortified
yellow-flesh cassava was compared to that of a whiteflesh
cassava, using salt, sugar, and salt–sugar solutions at
different temperatures (30, 45, 60 C) and fixed cube/solution-
ratio. Water loss (WL) and solids gain (SG) data
were fitted by non-linear regression using four models
(Page, Weibull, Azuara, and Peleg). Azuara model was
most appropriate in describing OD kinetics for both cultivars.
Azuara estimates for equilibrium WL and equilibrium
SG, respectively, ranged between 0.101–0.120 and
0.049–0.094 g/g for salt solution, 0.158–0.212 g/g and
0.107–0.268 g/g for sugar solution and 0.234–0.306 g/g
and 0.189–0.276 g/g for salt–sugar solution. The best
conditions for OD of both cultivars by salt solution and
sugar solution was at 60 C and 45 C, respectively, while
that for salt–sugar solution varied with cultivar. Increasing
temperature increased water loss and solids gain. Salt-OD
conformed to Arrhenius temperature dependence of diffusivity,
but sugar-OD and salt–sugar-OD did not. Micrographs
reveal biofortified yellow-flesh cassava was more susceptible to cell wall collapse than white-flesh cassava.
Extent of dehydration by OD agents ranked: salt–sugar[
sugar[salt. Osmotic dehydration may be useful as a
means of dehydration for cassava prior to drying, and is
especially relevant for the carotenoids-rich biofortified
yellow cassava.