After having been doing a lot better thanks to finding delicious waxy potatoes I feel like serotonin symptoms are back to square one, I had to change potatoes variety and the difference is (unfortunately) remarkable. A couple of other things could be blamed though, but since most potatoes give me instant stomach pain I decided to start this thread so people can share their experience with potatoes varieties, how to identify waxy ones etc..
Here is a paper on the matter:
https://www.google.co.uk/url?sa=t&r...sg=AFQjCNGCA2E8WEzGVucibi53_LWDs8lV8A&cad=rja
Wikipedia entry: Waxy potato starch - Wikipedia
Here is a paper on the matter:
https://www.google.co.uk/url?sa=t&r...sg=AFQjCNGCA2E8WEzGVucibi53_LWDs8lV8A&cad=rja
Let’s start by defining what we mean by waxy and mealy potatoes. According to
Professor Diane McComber (Iowa State University, retired; J. Food Sci. 1988,
53: 1423-1426) sensory panelists describe cooked waxy potatoes as moist,
mushy, and smooth, while cooked mealy potatoes are harder, drier, and produce
a sensation of particulate matter in the mouth. Waxy potatoes tend to have a thin
skin, are less dense, and contain lower levels of starch (about 16% on a wet
weight basis) and higher moisture. Mealy potatoes tend to have thicker skins, are
denser, and contain more starch (about 22% on a wet weight basis) and less
moisture. On a molecular level, the starch in waxy potatoes is composed almost
entirely of the large branched molecule called amylopectin, while the starch in
mealy potatoes is composed of a mixture of amylopectin (about 74%), and the
much smaller linear amylose molecule (about 26%). Both amylopectin and
amylose are polysaccharides, which function as storage forms of glucose.
Further research by Professor McComber (J. Agric. Food Chem. 1994, 42: 2433-
2439) showed that when high-starch Russet Burbank potatoes were cooked
(steamed) the potato cells became “completely engorged with gelatinized starch”,
in contrast to two varieties of low-starch waxy potatoes (Pontiac and LaSoda),
which appeared to be “only 30-50% filled” with swollen starch granules. Using
nuclear magnetic resonance spectroscopy (NMR) the higher level of starch
granules in Russet Burbank potatoes were observed to absorb more moisture
while less of the moisture in the lower-starch waxy potatoes was absorbed by the
swollen starch granules leaving more free moisture. This explains why mealy
potatoes are perceived as dry while waxy potatoes are characterized as moist.
On eating, the waxy potatoes release the loosely held water that is not bound up
by the lower level of gelatinized starch.
Interestingly, Professor McComber’s research showed in both the waxy and
mealy varieties the cells of steamed potatoes were intact and not collapsed when
visualized by scanning electron microscopy (SEM). Her research also showed
that calcium and magnesium ion concentrations were higher in Russet Burbank
potatoes than they were in the Pontiac variety of waxy potatoes. Calcium and
magnesium ions are known to strengthen pectin, the polysaccharide that is part
of the cell wall structure, and more importantly, acts as a glue to hold the cells
together. These observations led Professor McComber to agree with earlier
research (Am. Potato J. 1980 57: 141-149), which concluded that the cells of
steamed mealy potatoes resist separation into individual cells, but break “into
particulate masses” producing a texture that is less smooth than waxy potatoes.
[...]
These researchers found that more pectin was released when
mealy potatoes were boiled compared with waxy potatoes. Furthermore, these
researchers concluded from transmission electron microscopy (TEM) the release
of more pectin from the cooked mealy variety of potatoes resulted in cell wall
loosening and increased cell sloughing (most likely clumps of cells as suggested
by McComber) compared with waxy potatoes.
Wikipedia entry: Waxy potato starch - Wikipedia
Through traditional breeding techniques an amylose-free mutant was obtained without genetic manipulation. Since 2005 the first natural potato variety Eliane is being cultivated and marketed by the starch company AVEBE.