Citric acid is a weak
organic acid, and it is
a natural preservative
and is also used to add
an acidic, or sour,
taste to foods and soft
drinks. In
biochemistry, it is
important as an
intermediate in the
citric acid cycle and
therefore occurs in the
metabolism of virtually
all living things. It
can also be used as an
environmentally benign
cleaning agent.
Citric acid exists in
greater than trace
amounts in a variety of
fruits and vegetables,
most notably citrus
fruits. Lemons and limes
have particularly high
concentrations of the
acid; it can constitute
as much as 8% of the dry
weight of these fruits
(about 47 g/L in the
juices). The
concentrations of citric
acid in citrus fruits
range from 0.005 mol/L
for oranges and
grapefruits to 0.30
mol/L in lemons and
limes. Within species
these values vary
depending on the
cultivar and the
circumstances in which
the fruit was grow.
History
The discovery of citric
acid has been credited
to the 8th century
Persian alchemist Jabir
Ibn Hayyan (Geber).
Medieval scholars in
Europe were aware of the
acidic nature of lemon
and lime juices; such
knowledge is recorded in
the 13th century
encyclopedia Speculum
Majus (The Great
Mirror), compiled by
Vincent of
Beauvais.[citation
needed] Citric acid was
first isolated in 1784
by the Swedish chemist
Carl Wilhelm Scheele,
who crystallized it from
lemon juice.
Industrial-scale citric
acid production began in
1890 based on the
Italian citrus fruit
industry.
In 1893, C. Wehmer
discovered that
Penicillium mold could
produce citric acid from
sugar. However,
microbial production of
citric acid did not
become industrially
important until World
War I disrupted Italian
citrus exports. In 1917,
the American food
chemist James Currie
discovered that certain
strains of the mold
Aspergillus niger could
be efficient citric acid
producers, and Pfizer
began industrial-level
production using this
technique two years
later, followed by
Citrique Belge in 1929.
In this production
technique, which is
still the major
industrial route to
citric acid used today,
cultures of Aspergillus
niger are fed on a
sucrose or
glucose-containing
medium to produce citric
acid. The source of
sugar is corn steep
liquor, molasses,
hydrolyzed corn starch
or other inexpensive
sugary solutions. After
the mould is filtered
out of the resulting
solution, citric acid is
isolated by
precipitating it with
lime (calcium hydroxide)
to yield calcium citrate
salt, from which citric
acid is regenerated by
treatment with sulfuric
acid.
General Notices
C6H8O7,H2O 210.1
5949-29-1
Citric Acid Monohydrate
complies with the
requirements of the 3rd
edition of the European
Pharmacopoeia [0456].
These requirements are
reproduced after the
heading 'Definition'
below.
Ph Eur
Definition:
Citric acid monohydrate
contains not less than
99.5 per cent and not
more than the equivalent
of 101.0 per cent of
2-hydroxypropane-1,2,3-tricarboxylic
acid, calculated with
reference to the
anhydrous substance.
Characters:
A white, crystalline
powder, colourless
crystals or granules,
efflorescent, very
soluble in water, freely
soluble in alcohol,
sparingly soluble in
ether.
Identification:
First identification: B,
E.
Second identification:
A, C, D, E.
A. Dissolve 1 g in 10 ml
of water R. The solution
is strongly acidic
(2.2.4).
B. Examine by infrared
absorption
spectrophotometry
(2.2.24), comparing with
the spectrum obtained
with citric acid
monohydrate CRS after
drying both the
substance being examined
and the reference
substance at 100°C to
105°C for 24 h.
C. Add about 5 mg to a
mixture of 1 ml of
acetic anhydride R and 3
ml of pyridine R. A red
colour develops.
D. Dissolve 0.5 g in 5
ml of water R,
neutralise using 1M
sodium hydroxide (about
7 ml), add 10 ml of
calcium chloride
solution R and heat to
boiling. A white
precipitate is formed.
E. It complies with the
test for water (see
Tests).
Tests:
APPEARANCE OF SOLUTION:
Dissolve 2.0 g in water
R and dilute to 10 ml
with the same solvent.
The solution is clear
(2.2.1) and not more
intensely coloured than
reference solution Y7,
BY7 or GY7 (Method II,
2.2.2).
READILY CARBONISABLE
SUBSTANCES: To 1.0 g in
a cleaned test tube add
10 ml of sulphuric acid
R and immediately heat
the mixture in a
water-bath at 90±1°C for
60 min. Immediately cool
rapidly. The solution is
not more intensely
coloured than a mixture
of 1 ml of red primary
solution and 9 ml of
yellow primary solution
(Method I, 2.2.2). OXALIC ACID: Dissolve
0.80 g in 4 ml of water
R. Add 3 ml of
hydrochloric acid R and
1 g of zinc R in
granules. Boil for 1
min. Allow to stand for
2 min. Transfer the
supernatant liquid to a
test-tube containing
0.25 ml of a 10 g/l
solution of phenylhydrazine
hydrochloride R and heat
to boiling. Cool
rapidly, transfer to a
graduated cylinder and
add an equal volume of
hydrochloric acid R and
0.25 ml of a 50 g/l
solution of potassium
ferricyanide R. Shake
and allow to stand for
30 min. Any pink colour
in the solution is not
more intense than that
in a standard prepared
at the same time in the
same manner using 4 ml
of a 0.1 g/l solution of
oxalic acid R (350 ppm,
calculated as anhydrous
oxalic acid).
SULPHATES (2.4.13):
Dissolve 1.0 g in
distilled water R and
dilute to 15 ml with the
same solvent. The
solution complies with
the limit test for
sulphates (150 ppm).
ALUMINIUM (2.4.17): If
intended for use in the
manufacture of dialysis
solutions, it complies
with the test for
aluminium. Dissolve 20 g
in 100 ml of water R and
add 10 ml of acetate
buffer solution pH 6.0
R. The solution complies
with the limit test for
aluminium (0.2 ppm). Use
as the reference
solution a mixture of 2
ml of aluminium standard
solution (2 ppm Al) R,
10 ml of acetate buffer
solution pH 6.0 R and 98
ml of water R. To
prepare the blank use a
mixture of 10 ml of
acetate buffer solution
pH 6.0 R and 100 ml of
water R. HEAVY METALS (2.4.8):
Dissolve 5.0 g in
several portions in 39
ml of dilute sodium
hydroxide solution R and
dilute to 50 ml with
distilled water R. 12 ml
complies with limit test
A for heavy metals (10 ppm). Prepare the
standard using lead
standard solution (1 ppm
Pb) R.
WATER (2.5.12): 7.5 per
cent to 9.0 per cent,
determined on 0.500 g by
the semi-micro
determination of water. SULPHATED ASH (2.4.14):
Not more than 0.1 per
cent, determined on 1.0
g.
BACTERIAL ENDOTOXINS
(2.6.14): If intended
for use in the
manufacture of
parenteral dosage forms
without a further
appropriate procedure
for the removal of
bacterial endotoxins,
not more than 0.5 I.U.
of endotoxin per
milligram.
Assay:
Dissolve 0.550 g in 50
ml of water R. Titrate
with 1M sodium
hydroxide, using 0.5 ml
of phenolphthalein
solution R as indicator.
1 ml of 1M sodium
hydroxide is equivalent
to 64.03 mg of C6H8O7.
Storage:
Store in an airtight
container.
Labelling:
The label states
- where applicable, that
the substance is free
from bacterial
endotoxins,
- where applicable, that
the substance is
intended for use in the
manufacture of dialysis
solutions.
Main Uses :
Imparts
fine tangy flavour and
sequesters heavy metal
ions in soft drinks.
Preserves flavour,
appearance and
consistency in canned
fruits and vegetables.
Enhances flavour of
fruits, promotes sucrose
inversion in candies.
Acts as a synergist to
antioxidants due to complexation of heavy
metal ions.
Helps to create the
bubbling and fizzing
effect in effervescent
tablets. Used in various
creams, ointments and
shampoos.
Packaging :
25 Kg
"Polyethylene-lined
multi-wall paper bags Note :- Rate of the
products Mention in the Website
will be verified by day to day
fluctuation in the Indian Agro
Market Actual Rate of the
Products will be provide at the
time of final Confirmation of
Order
CITRIC ACID ANHYDROUS
(FCC / USP)
Description : Citric
Acid Anhydrous is
available as free
flowing, translucent
white crystals/granules,
practically odourless
with slighty hygroscopic
and tart acidic taste.
Citric Acid is a widely
used and
environment-friendly
acidulant.
GENERAL CHARACTERISTICS
*Formula : C6 H8 O7
*Molecular weight :
192.13
*Appearance : White
Crystals
*Taste : Tart acid Taste
*Odour : Practically
Odourless
*CAS No :. 77 - 92 - 9
*Specific Gravity :
1.665
*Melting Point : 153o C
*PH of 0.1 N solution :
2.2
*Solubility @ 25oC in :
In water - 162 gm/100 ml
water
In alcohol - 59 gm/100ml
alcohol
In ether - 0.75 gm/100ml
ether
STANDARD SPECIFICATIONS
*Standards : BIS / USP
XXIII / BP 93 / DAB /
FCC / IP
*Identification :
Positive for Citrates
*Assay : 99.5 - 100.5 %
*Water ( Anhydrous basis
) : Max 0.5 %
*Residue on Ignition :
Max. 0.05 %
*Oxalate - Meets USP /
FCC Tests
*Sulfate - Meets USP
tests
*Arsenic ( as As ) - Max
1. ppm.
*Heavy metals ( As Pb )
- Max. 5 ppm.
*Readily Carbonizable
Substances - Meets USP /
FCC tests
*Lead - Max. 0.5 ppm
Main Uses :
*Imparts fine tangy
flavour and sequesters
heavy metal ions in soft
drinks.
*Preserves flavour,
appearance and
consistency in canned
fruits and vegetables.
*Enhances flavour of
fruits, promotes sucrose
inversion in candies.
*Acts as a synergist to
antioxidants due to
complexation of heavy
metal ions.
*Helps to create the
bubbling and fizzing
effect in effervescent
tablets. Used in various
creams, ointments and
shampoos.