About Frying colour
The colour of fried products is determined by the reducing
sugar content in the potatoes. This makes reducing sugar
(glucose, fructose) an important parameter in the quality
control of potatoes for processing. Different potato
products have a different tolerance for reducing sugars.
Here is some guidance:
Reducing Sugar Content
Methods for testing potatoes on frying quality
There are different methods to measure the sugars. Some methods rely on a
direct measurement of the sugars, other methods involve the standard preparation
of a product, e.g. frying a number of strips from the core of a potato tubers.
Benefit of frying the product is that any variation of reducing sugars between
and even within tubers (sugar ends) becomes visible.
For this method, we offer you a catering style fryer with
precise temperature and timer control, a strip cutter set
and the USDA French fry color card. Suggested measurement
method is included.
Details on fryer, strip cutter and USDA french fry color
When recommended: recommended method,
provided a good quality fryer is used and temperature of the
fryer is verified. Training is recommended.
In association with Martin Lishman, we offer you this
Glucolis do it yourself field kit, that allows you to
test for glucose in potato tubers.
This kit is no longer in production
- Easy-to-use kit, requires no special training to
Glucolis Product Details...
When recommended: everywhere no fryer
can be used
Tips on measuring frying colour
A sample size of twenty tubers is generally considered
sufficient to assess frying colour of a potato lot.
Localized dark spots can be an indication of low dry matter potato tissue,
resulting in poor texture (secondary growth).
Tips on how to improve the quality of potatoes for frying