Food Microstructure and Starch Digestion - Advances in Food and Nutrition Research - page 151

appear intact and retained their normal morphology after cooking to the
optimum levels. Hydrolysis of the starch by SIF containing pancreatic amy-
lases led to the digestion of starch and its remnants progressively as evidenced
by the homogeneous background of empty cells ( Fig. 4.7 B). After 45 min of
simulated small intestinal digestion, most of the tuber cells showed an empty
cavity that is created due to the hydrolysis of starch by the digestive enzymes
( Fig. 4.7 C and D). The cell walls stayed intact during and after the digestion
which showed that SIF had no affect on the cooked potato tuber cell walls,
which are generally made up of cellulose and hemicellulose materials.
Figures 4.8 A-D and 4.9 A-D show scanning electron micrographs of
freeze-dried samples taken during in vitro small intestinal digestion of freshly

Parenchyma cells Intact cell walls

A

B

Cooked tuber parenchyma

C D

Figure 4.8 Scanning electron micrographs taken during in vitro small intestinal diges-
tion of starch in Agria cooked potatoes. (A) Sample taken after 0 min, (B) 5 min, and
(C and D) 30 min (at different magnifications). As artifacts produced by freeze drying
are present, these micrographs do not necessarily represent the structure prior to freeze
drying. Reproduced from Bordoloi, Singh, et al. (2012) with permission from Elsevier.