NEW OLIVE GROWING
AND PRESSING PROCESSES
The most important aspect of olive growing for the future
involves the perfecting of basic systems and techniques: pruning, fertilization,
phytohealth defences, mechanisation, and above all the creating of new
systems according to more modern and rational agronomic criteria.
This is the phase that will meet with the greatest number of problems
over the next few years due to high costs and the growing scarcity of
skilled labour capable of carrying out this important and equally delicate
operation. Modern-day criteria suggest the pruning of olive trees in
a less aggressive manner than in the past. Excessive pruning in fact
causes the plant to shift its own biological equilibrium towards the
differentiation between "leaf" buds and "flower"
buds, thus contributing towards the so-called "alternation"
in production that represents one of the main drawbacks in modern and
profitable olive growing.
With the developing of several "clonal selections" of specific
varieties, still in the experimental phase, we will eventually finish
upwith mechanical and inline pruning, and even non-pruning.
Less pruning is therefore the answer to keeping growing costs down and
achieving a superior "olive yield", if combined however, with
a suitable and above all "targeted" fertilization. Leaf-fertilization
is subsequently taking on a more important role, and while it must not
replace in-depth fertilization (or composting), it can often be integrated
at extremely low costs compared to the results obtained. With targeted
leaf-fertilization based on specific products consisting of active,
organic biostimulators (vitamins, enzymes, humic and fulvic acids)
as well as macro and micro elements indispensable for the physiological
processes of the tree, surprising results can be obtained at more than
acceptable costs, with production increases of up to 100%.
This however, requires intervention during the fundamental phases of
the biological phases, and consequently the productive life of the olive
tree: vegetative recovery, pre-flowering, setting, hardening of the
stone and oil enrichment.
For the complete mechanisation of the olive grove the system must be
pre-arranged right from the beginning, with regard to both the choice
of cultivars and/or clonal varieties, and the form of plant breeding
and arrangement of the installations. With traditional olive growing,
(meaning trees already in existence), partial forms of mechanisation
can be introduced, with mechanical aids like the vibrating combs which
stand out thanks to their ability to double and even triple the quantity
of oil produced per-capita per day, with considerable cuts in labour
costs as well.
In designing a new plantation it is essential to consider the precocity
of entering in production, the high and above all constant productivity,
the rationality depending on the ecosystem, and the farm's requirements.
After a correct mechanical preparation of the land and an adequate composting
of the soil for re-establishing fertility, the choice of the most appropriate
varieties and clonal selections according to the environment and climate
is without doubt the aspect requiring the greatest care. In fact each
variety possesses specific intrinsic, morphological and functional characteristics.
For example, every Tuscan olive grower knows that the Leccino
variety has a greater resistance to low temperatures than the Frantoio
variety, however within the range of certain varieties there are already
genetic selections (clones) available on the market that are particularly
resistant to certain adverse conditions and phytpathologies, and numerous
other varieties are in the process of being studied and/or patented.
At this stage it is important to point out that each variety produces
a "monocultivar" oil generally characterised by a marked organoleptic
typicality, in other words by its own specific taste, also influenced
by the pressing and extraction systems utilised.
While still in Tuscany, we should also point out for example, that the
oil of the Leccino variety tends to be "sweeter" in
comparison to that of the Frantoio variety, which is instead
more "fruity", and also more "pungent" and "bitter".
Fruitiness, bitterness, pungency, sweetness represent the most important
sensory attributes of olive oil and may vary considerably depending
on the cultivars (in Tuscany alone approximately 80 have been identified
up to date).
Moreover, these varieties often present very marked differences, also
deriving from their ripening periods.
The Leccino for example, is a precocious variety while the Moraiolo,
another classic Tuscan cultivar, is a late ripener. In a modern and
rational olive growing business it is most important to divide the various
cultivars into sectors in order to be able carry out a differentiated
picking in line with the ripening, and thus obtain perfect mono-variety
oils with different characteristics, after which it will be the olive
oil producer's responsibility to formulate the most appropriate mixtures
according to the company's requirements.
Consequently, you must also keep these organoleptic diversities in mind
when planning a new system, as well as evaluate the markets demands
and trends, in striving for a product "typicality", increasingly
more important for leaving the masses behind and creating your own commercial
strategy. For this purpose it is essential for only olive saplings of
certain origin to be purchased, even better if certified
and guaranteed both from a genetic and phyopathological point of view.
Despite their higher unitary costs, the precocious entering into production,
constant productivity, and specific genetic characteristics like higher
resistance to natural adversities of certain "clones", will
more than repay the careful olive grower.
The final organoleptic characteristics of olive oil (in other words,
the flavour), are the result of various factors:
the production ecosystem (soil, altitude, climate), the olive
varieties (and their degree of ripening), and lastly, the pressing
and extracting techniques. Likewise with the ecosystem and variety,
by intervening on the pressing and extracting techniques, the
organoleptic profile of a product can be radically altered.
The main olive transforming phases are as follows:
- Washing and ventilating: to remove leaves and impurities.
- Pressing: mechanical pressing of the olives.
- Kneading: homogenisation of the paste obtained.
- Extraction: of the liquid part (mixture of water and oil)
from the solid part (olive residues).
- Separation: of the oil from the vegetation water.
The pressing system in particular (meaning the different
mechanical pressing methods), that the olive skin, pulp and stone are
subjected to has the greatest effect on the organoleptic profile of
- Stone Muller and Rollers: exalt the Sweetness
and the Yellow-gold
- Hammer press:
exalt the Bitterness and the Green-gold
- Cogged disc press:
exalt the Pungency and the Brilliant
The Extraction phase is also a determining factor
with regard to the organoleptic profile and may be of the following
- Traditional: or by pressure with a fiscoli press.
- Modern: or centrifuge
- Sinolea: or by
percolation and double extraction.
Very different results are obtained from each of these
systems, with respect to both the chemical and organoleptic characteristics
and also the density and appearance of the product. With the modern
kneading-decanter systems we can also intervene with other parameters
like kneading times, temperature of the paste, and percentage of water
added in the decanter, all relevant in our quest for the highest quality.
On summing up this brief description about how transformation techniques
can greatly influence the final "flavour" of the product,
and on the basis of my experience and experimentation with almost every
type of mono-variety oil system in existence for the major Tuscan cultivars,
I wish to point out how even the different oil-producing machinery manufacturers
contribute towards the characterisation to the product. To be more precise,
if we use the same crop of olives and the same type of machinery, produced
however by different manufacturers, we often obtain completely different
The technical themes described above are of quite recent acquisition
and still in the process of being studied and analysed by the most important
researchers and experts in this sector, however, from all this it appears
clear that the variables regarding the differentiation and research
for the highest product quality are many and varied.
The careful producer, by starting out with a specific ecosystem, can
intervene on the varieties, targeting the ones that are most suited
to his own type of product. Lastly, by choosing the most appropriate
transformation system (and most suitable manufacturer), he will be able
to exalt certain characteristics and tone down others, for the purpose
of highlighting the aftertastes and hidden aromas, and thus be able
to perfect his own product in his quest for the best possible commercial