3.3. Refining and new technological processes
The main issues in grain refining appear to be the following: 1)
to determine how to maintain the protective compounds of whole
grains that are contained mainly in the germ and bran fractions
while avoiding the contaminants in the outermost layers of the
grain; 2) to reduce the levels of sugars, salts and fats; and 3) to
develop new cereal products that are accepted by the consumer.
A review of the literature suggests several questions to be
addressed in research, as follows:
3.3.1. First transformation
Can we preserve the germ fraction in flour without prior isolation,
stabilisation and reincorporation? Regarding the contamination
of the outer layers of the grain, is this currently a real risk to
health? Further studies should be conducted to definitively answer
this question. Regarding the aleurone layer, there are now welldeveloped
techniques for isolating it or maintaining it during
fractionation (while excluding the outermost layers, such as the
pericarp) (Barron et al., 2012), but can these be widely applied and
are they sustainable in the long term in terms of their energy cost?
In addition to offering complete or semi-complete flours, these
issues can be addressed by acting on the ‘formulation’ lever, i.e.,
how flour is refined and whether fibre and/or the previously isolated
aleurone layer are added, with the risk, however, of losing
some of the ‘physical structure effects’ of whole grain.
3.3.2. Second transformation
At the level of the second transformation, several issues should
also be addressed. Firstly, the use of softer technologies for shaping
grain products should be further studied (“minimal processing”).
The literature suggested the following areas of research: the effects
of cereal pre-fermentation/germination on the nutrient density of
cereal products and reconsidering the hydro-thermo-mechanical