This document discusses the key characteristics of water that are important for pasta production. It covers both the microbiological and chemical parameters of water quality based on EU directives. Microbiologically, water must be free of pathogens and indicators of fecal contamination. Chemically, the document outlines limits for various metals, salts, hydrocarbons and parasiticides. It also discusses how water interacts with pasta ingredients like semolina during dough formation and gelatinization, and how its characteristics can positively or negatively impact the finished product. Water treatment methods are outlined to ensure water meets food safety and technological standards.

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One of the key prerequisites pasta
producers should always keep in
mind is the definition of quality
parameters for the ingredients
utilized. The desire to obtain a
product with the best quality char-
acteristics must meet the implicit
and explicit requisites the
consumer looks for at the time of
purchase.
The two “cornerstones” that
form the basis of improvement
in the production of pasta
goods (which during their
preparation and cooking
undergo various types of struc-
tural stress) are durum wheat
semolina and water.
In issues 16 and 17 of the Profes-
sional Pasta Newsletter we
dedicated ample attention to
the quality of durum wheat
semolina and in this article we
will be looking at the main
characteristics of water.
A number of the characteristics
specific to water are known.
From a chemical standpoint it is
a dipolar molecule, which
means that the imbalance of its
charges makes it an ideal
solvent for certain molecular
classes. In general, this impor-
tant property can be described
as the ability to solubilize
compounds containing polar
or ionic groups (given the abil-
ity to form hydrogen and ion
bonds with neutral organic
compounds and crystalline
solids).
For example, when we place a
crystalline solid (such as sodium
chloride) in water, its molecules
come into contact with the salt’s
rigid, well-organized structure,
given the strong attraction
between the individual ions
and the solvent, and are
“rapidly” hydrated. As a result,
each ion becomes completely
surrounded by water mole-
cules.
With semolina, and as with egg
and other ingredients normally
utilized to produce the various
types of pasta goods, organic
molecules (such as carbohy-
drates, alcohols, aldehydes and
ketones) are present that are
characterized by special molec-
ular groups (hydroxyls) that
render them easily-soluble in
water. When this occurs,
specific (hydrogen) bonds are
formed.
Another class of compounds
that may be found in dough or
fillings, even if in reduced
quantity, are composed of
“amphipatic” molecules that
are dispersed in water. These
tend to arrange themselves
creating micelles inside which
are areas with characteristics
the opposite of those found in
water. (For example, consider
what happens with soap. Any
fats or oils present are incorpo-
rated into the micelles, but the
latter remain in solution given
the hydrophilic nature of the
micelle’s external surface.)
We have mentioned some of
the characteristics of water in
order to underscore the influ-
ence and importance they have
in determining the quality of
the finished product. In fact, if
magnified, these characteristics
can have a negative or positive
impact on the product being
produced.
Fresh pasta has a water content
of approximately 25-30% of its
weight, but this content is not
entirely available to the micro-
organisms present and is
partially bound to the solutes
found in the dough and filling.
Knowing the chemical and
microbiological characteristics
of the ingredients used is
clearly important in order to
guarantee a high level produc-
tion standard from a microbio-
logical, bromatological (prod-
uct stability and safety), tech-
nological and nutritional stand-
point.
In the production of pasta
goods, water quality must be
established on the basis of two
different needs: potability (set
by legislated standards) and
technological quality.
In terms of the first parameter,
it is a good idea to refer to EEC
directive number 98/83
COMMENTS ON THE MAIN QUALITY CHARACTERISTICS OF
WATER
by Alessio Marchesani

2. concerning the water quality
for human consumption, the
main provisions of which are
given in Tables (pages 14-15).
Microbiological quality at the
time of use for alimentary
production purposes must be
irreproachable and conform
with the standards given in
EEC directive no. 98/83, ref.
Table 1 (page 14).
There are three primary princi-
ples of reference on a microbio-
logical level: presence of patho-
genic microorganisms, indica-
tors of faecal contamination
and microorganisms that adul-
terate water.
Asamatteroffact,thereasonsthat
recommend against the use of
microbiologically-contaminate
water go beyond simple
conformity to legislated stan-
dards and professional ethics.
From a technological stand-
point, the presence of adulter-
ating bacteria or, even worse,
pathogens, creates serious
problems. If present, they affect
organoleptic properties (co-
lour, aroma, texture, etc.), but
also alimentary hygiene and
safety. The negative influence
encountered in fresh product
quality is also highly relevant to
dry pasta, especially in terms of
product colour.
Ultraviolet (UV) rays with a
wave length of between 0.1 and
0.4 micrometers are used espe-
cially in small- and medium-
sized production facilities.
These rays are generated by
mercury vapour lamps and the
water to be treated flows in
front of these lamps in shallow
streams approx. 25 cm deep.
Meticulous attention should be
given to the treatment used for
water disinfection. In addition,
if the technological circuit of
the water is complex, it is
important to guard against any
contact between clean water
and waste water, as well as
against any seeping in of
polluted water from the plumb-
ing system on the company
premises.
EEC directive no. 98/83 gives
the chemical reference limits
for heavy metals, salts, hydro-
carbons and parasiticides (see
Table 2 on page 14).
The most important chemical
parameters are: the ammonia
ion (NH4
+), that is an indicator
of the microbiological status of
the water table from which the
water is drawn; the nitrous ion
(NO2
-), another pollution indi-
cator; the nitric ion (NO3
-),
which must not exceed 50 mg/l;
chlorides (Cl-), the ferrous ion
(Fe2+), anionic surface-active
agents and parasiticides.
On a technological level, one of
the basic parameters is the over-
all mineral content (expressed
as dry residue at 180°C) and
given in Table 3 (page 15), which
should not exceed 500 mg/litre
for pasta goods.
In certain cases it may be neces-
sary to reduce the overall hard-
ness of the water to be used. In
essence, this means reducing
calcium and magnesium salt
content (primarily HCO3
-, Cl-,
SO4
2-, NO3
-) by “softening” the
water using ion-exchange
resins.
Treatments performed to
render water drinkable concern
its chemical, physical,
organoleptic (in this context, we
speak of “correction”) and
microbiological (here, on the
other hand, we speak of “purifi-
cation”) characteristics. The
main adjustments performed
concern unpleasant smell and
taste, lack of clarity or any
discolouration, concentration of
iron and manganese ions and
hardness.
There are various phases in a
purification system: pre-
cholorination, performed in
the past using sodium hypo-
chlorite and today using
gaseous chlorine or chlorine
dioxide that perform an oxidiz-
ing action on organic and inor-
ganic chemical compounds
and have a bactericidal effect
on microorganisms in the
water; flocculation and
decantation; filtration over
activated carbon; ozonization
in which the ozone, given its
highly oxidizing effect on
organic molecules, affects the
biological forms to reduce the
bacteriological and viral count
and kill the majority of the
compounds that generate bad
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3. odours; post-chlorination,
similartotheinitialtreatment.
Because chlorine in water used
for the dough creates a signifi-
cant decline in product colour,
attention should be paid to the
residue content. In addition,
high concentrations could
cause the formation of chloro-
phenol with its accompanying,
unpleasant odour.
In terms of the more-specifi-
cally technological aspect of
water, this can be very impor-
tant during dough formation
(and as a result the gluten
lattice structure). This is the
phase in which intra- and
inter-molecular reciprocal
interactions are created
between the various protein
fractions that give the product
its desired structure and
malleability.
In particular, the balance
between the gliadin and gluten
fractions has a significant influ-
ence on product structure.
Plus, the presence of salts in the
water could influence the
formation of ion bonds
between the protein fractions
of the gluten.
The polar amino acid groups
involved in the formation of
ion bonds are primarily -NH3
+
(lysine) and -COO- (gluta-
mate). The stabilization phase
of the gluten structure is attrib-
utable to the formation of
hydrogen bonds between the
chains of the protein fractions
of which the gluten is formed.
Water also acts as a solvent for
the starchy fractions. Although
amylose (linear fraction of
starch) is virtually insoluble in
water, becoming partially solu-
ble when warm, amylopectin
(branched fraction of starch) is
always insoluble in water. As a
result of the damage suffered
by the native starch granules
during flour milling, solubility
levels become high, just as
occurs with starch that
undergoes a pre-gelatinization
process. In this case, exact
knowledge of the level of
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TABLE 1 - MICROBIOLOGICAL PARAMETERS
Parameter Parameter value (number/100ml)
Escherichia coli (E. coli) 0
Enterococci 0
TABLE 2 - CHEMICAL PARAMETERS
Parameter
Parameter value
Units of measure (g/l)
Acrylamide 0.10
Antimonious 5.0
Arsenic 10
Benzene 1.0
Benzo(α)pyrene 0.010
Borous 1.0
Bromate 10
Cadmium 5.0
Chromo 50
Copper 1.0
Cyanide 50
1.2 Dichloroethane 3.0
Epichlorohyd 0.10
Fluorure 1.50
Lead 10
Mercury 1.0
Nickel 20
Nitrate (NO3
-) 50
Nitrite (NO2
-) 0.50
Antiparasites 0.10
Antiparasites -Total 0.50
Polycicle aromatics hydrocarbons 0.10
Selenium 10
Tetrachlorethylene - Trichloroethylene 10
Trihalomethane -Total 30
Vynil chloride 0.5
Chlorite 200
Vanadium 50

4. damage suffered by
the starch granules of
the semolina used in
pasta production be-
comes critical for opti-
mum dough prepara-
tion because it has a
direct bearing on how
muchwateristobeused
during the production
process.
Water interacts with
the starch and its
component fractions as
follow:
The gelatinization
phase can be a crucial
step in the preparation
of pre-cooked pasta in
which high produc-
tion temperatures and
water availability must
guarantee the desired
result (to gelatinize,
starch requires, simul-
taneously, a tempera-
ture of over 50°C and
water proportionate to
atleast0.4g/gofstarch).
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TABLE 3 - INDICATOR PARAMETERS
Parameter Parameter value Units of measure
Aluminium 200 g/l
Ammonium 0.50 mg/l
Chloride 250 mg/l
Colour
Reasonable values for the consumer
and without anomalous variations
Conductivity 2,500 Scm-1 at 20°C
Hydrogenion concentration >=6.5 e <=9.5 pH units
Iron 200 g/l
Manganese 50 g/l
Odour
Reasonable values for the consumer
and without anomalous variations
Oxidability 5.0 mg/l O2
Sulphate 250 mg/l
Sodium 200 mg/l
Flavour
Reasonable values for the consumer
and without anomalous variations
Colony count at 22 °C Without anomalous variations
Coliform bacteria at 37°C 0 Number/100 ml
Total organic carbon (TOC) Without anomalous variations
Torbidity
Reasonable values for the consumer
and without anomalous variations
Hardness*
Dry content at 180°C**
Disinfectant content***
Clostridium perfringens
(included spores)
0 Number/100 ml
* Recommended values: 15-50 °F ** Max. recommended values:1,500 ml/l *** Min. recommended values:0.2 ml/l (if utilized)