1986R1764 — EN — 01.07.1989 — 001.001 — 1
This document is meant purely as a documentation tool and the institutions do not assume any liability for its contents
►B COMMISSION REGULATION (EEC) No 1764/86
of 27 May 1986
on minimum quality requirements for tomato-based products eligible for production aid
(OJ L 153, 7.6.1986, p. 1)
Amended by:
Official Journal
No page date
►M1Commission Regulation (EEC) No 2318/89 of 28 July 1989 L220 49 29.7.1989
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COMMISSION REGULATION (EEC) No 1764/86
of 27 May 1986
on minimum quality requirements for tomato-based products
eligible for production aid
THE COMMISSIONOF THE EUROPEANCOMMUN ITIES,
Having regard to the Treaty establishing the European EconomicCommunity,
HavingregardtoCouncilRegulation(EEC)No426/86of24February
1986 on the common organization of the market in products processedfrom fruit and vegetables(
1), and in particular Article 6 (4) thereof,
Whereas Article 2 (1) of Regulation (EEC) No 426/86 provides for a
systemofproductionaidforcertainproducts;whereasArticle6(1)(b)of the Regulation lays down that aid shall be paid only for productswhich meet minimum quality standards to be laid down;
Whereastheaimofsuchqualityrequirementsistoavoidproductionof
products for which no demand exists or products which would createdistortion of the market; whereas the requirements must be based ontraditional fair manufacturing procedures;
Whereas with a view to implementing the production aid system this
RegulationmustbeappliedinconjunctionwithCommissionRegulation(EEC) No 1599/84 of 5 June 1984 laying down detailed rules for theapplication of production aid for products processed from fruit andvegetables(
2),aslastamendedbyRegulation(EEC)No1155/86(3),in
particular as regards examination of the processed products;
Whereas the quality requirements laid down in this Regulation are
measures for implementing the production aid system; whereas qualityrequirements for the marketing of the products are not yet establishedby the Community; whereas national requirements to that end maycontinuetobeappliedbytheMemberStates,providedtheyarecompat-ible with the provisions of the Treaty on the free movement of goods;
WhereastheManagementCommitteeforProductsProcessedfromFruit
andVegetableshasnotdeliveredanopinionwithinthetimelimitsetbyits Chairman,
HAS ADOPTED THIS REGULATION:
Article 1
This Regulation lays down the minimum quality requirements which
tomato-basedproducts,asdefinedinArticle1(2)ofRegulation(EEC)No 1599/84, shall meet in order to benefit from the production aidprovided for in Article 2 (1) of Regulation (EEC) No 426/86.
Article 2
ForthemanufactureoftheproductsreferredtoinArticle1onlyfresh,
red, healthy, ripe, sound and clean tomatoes (fruit of Lycopersicum
esculentumP. Mill), suitable for processing, shall be used and, where
applicable,onlythevarietiesprovidedforinArticle1(2)ofRegulation(EEC) No 1599/84.
(1) OJ No L 49, 27. 2. 1986, p. 1.
(2) OJ No L 152, 8. 6. 1984, p. 16.
(3) OJ No L 105, 22. 4. 1986, p. 24.
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TITLE I
Requirements for peeled and unpeeled tomatoes
Article 3
For the purposes of this Title, ‘peeled tomatoes'means:
— peeled frozen tomatoes, whole or non-whole,
and
— peeled preserved tomatoes, whole or non-whole, as defined in
Article 1 of Regulation (EEC) No 1599/84;
‘unpeeled tomatoes'means:
unpeeledpreservedtomatoes,wholeornon-whole,asdefinedinArticle
1 of the abovementioned Regulation.
Article 4
1. Only the following ingredients may be added to peeled or
unpeeled tomatoes:
— water,
— tomato juice,— tomato concentrate,— common salt (sodium chloride),— naturalspices,aromaticherbsandtheirextracts,andnaturalaromas.
As additives in the manufacture of peeled or unpeeled tomatoes only
citric acid (E 330) and calcium chloride (509) may be used.
2. The quantity of added common salt must not exceed 3 % of the
net weight and when calcium chloride is added, total calcium-ioncontent must not exceed 0,045 % in whole style and 0,080 % innon-wholestyle.Whendeterminingthequantityofaddedcommonsalt,the natural content of chlorides shall be considered as equal t o2%o f
the dry weight content.
3. Added tomato juice and tomato concentrate shall meet the
minimum requirements laid down in Title II.
Article 5
1. Peeled and unpeeled tomatoes shall be free from flavours and
odoursforeigntotheproductandtheircolourshallbecharacteristicforthe variety used, properly processed.
2. Peeled tomatoes shall be virtually free from peel. The peel of
unpeeledtomatoesshallbevirtuallyintact.Wholepeeledandunpeeledtomatoes shall also be virtually free from blemished units.
3. The mould count of preserved tomatoes (the tomatoes and the
coveringliquid)shallnotexceed50%positivefieldsandthepHlevelshall not exceed 4,5.
Article 6
1. TheproductsshallbeconsideredascomplyingwithArticle5(2)
when the following tolerances for defects are not exceeded:
— blemishes: 35 cm
2aggregate area;
— presence of peel (peeled tomatoes):
— whole style: 300 cm2aggregate area,
— non-whole: 1250 cm2aggregate area;
— absence of peel (unpeeled tomatoes):
— whole style: 300 cm2aggregate area,
— non-whole: 1250 cm2aggregate area.
The tolerances fixed are per 10 kg net weight.2. For the purposes of paragraph 1:
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(a) ‘blemishes' means areas into which lesions on the surface have
penetrated and as a result thereof contrast strongly in colour ortexture with the normal tomato tissue and should normally havebeen removed during processing;
(b) ‘peel'meansbothpeeladheringornotadheringtothetomatoflesh
and peel found loose in the container.
Article 7
1. Inrespectofpeeledorunpeeledpreservedtomatoes,thetomatoes
andcoveringliquidinacontainershalloccupynotlessthan90%ofthewater capacity of the container.
2. The drained net weight of whole peeled or unpeeled preserved
tomatoes shall on average be at least equal to 56 % of the watercapacity, expressed in grams, of the container.
3. When peeled or unpeeled preserved tomatoes are packed in glass
containers the water capacity shall be reduced by 20 ml before thepercentages referred to in paragraphs 1 and 2 are calculated.
▼
B
TITLE II
Requirements for tomato juice and tomato concentrate
Article 8
For the purposes of this Title ‘tomato juice'and ‘tomato concentrate'
mean the products defined in Article 1 (2) (n) and (o) of Regulation(EEC) No 1599/84.
Article 9
1. Only the following ingedients may be added to tomato juice and
tomato concentrate:
— common salt (sodium chloride),
— naturalspices,aromaticherbsandtheirextracts,andnaturalaromas.
2. As an additive in the manufacture of tomato juice and tomato
concentratecitricacid(E330)maybeused.Furthermore,inthemanu-facture of:
— tomato juice with a dry weight content of less than 7 %, ascorbic
acid(E300)maybeused.However,theascorbicacidcontentshallnot exceed 0,03 % by weight of the finished product,
— tomato concentrate in powder form, silicon dioxide (551) may be
used.However,thesilicondioxidecontentshallnotexceed1%byweight of the finished product.
3. The quantity of added common salt shall not exceed:
(a) 15 % by weight of the dry weight content for tomato concentrate
having a dry weight content exceeding 20 %; and
(b) 3%byweightofthenetweightforothertomatoconcentratesand
for tomato juice.
When determining the quantity of added common salt, the natural
content of chlorides shall be considered as equal t o2%o ft h ed r y
weight content.
Article 10
1. Tomato juice and tomato concentrate shall have:
(a) a characteristic red colour; and(b) a good flavour, characteristic of a properly processed product.
Theproductsshallbefreeofanyforeigntaste,inparticularthetasteof
burned or caramelized product.
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2. Tomato juice and tomato concentrate shall be:
(a) free of visible extraneous plant material, including skin, seeds and
other coarse parts of tomatoes;
(b) practically free of mineral impurities.
3. The requirements provided for in paragraph 2 are considered as
complied with when:
(a) anyextraneousplantmaterialscanbeestablishedonlybyintensive
examination by the naked eye; and
(b) the mineral impurities content does not exceed 0,1 % of the dry
weightcontent,reducedbyanyaddedcommonsaltand,inrespectof tomato concentrate in powder form, any added silicon dioxide.
4. Tomato juice and tomato concentrate shall have:
(a) an evenly divided texture and consistency indicating proper
processing practices;
(b) asugarcontentexpressedasinvertsugarofatleast42%byweight
of the dry weight content reduced by any added common salt;
(c) a total titratable acidity, expressed as crystallized monohydrate
citricacid,notexceeding10%byweightofthedryweightcontentreduced by any added common salt;
(d) a volatile acidity, expressed as acetic acid not exceeding 0,4 % by
weight of the dry weight content, reduced by any added commonsalt;
(e) a pH level not exceeding 4,5.
5. The mould count of tomato juice and tomato concentrate shall,
whendilutedwithwatertoreach8%dryweightcontent,notexceed70% positive fields. For tomato juice with a dry weight content of lessthan8%,thepercentageofpositivefieldsshallbereducedproportion-ally to the dry weight content.
TITLE III
Requirements for tomato flakes
Article 11
ForthepurposesofthisTitle‘tomatoflakes'meanstheproductdefined
in Article 1 (2) (m) of Regulation (EEC) No 1599/84.
Article 12
1. Tomato flakes shall have:
(a) a characteristic red colour; and(b) a good flavour, characteristic of a properly processed product; and(c) be free from flavours and odours foreign to the product.
2. The dry weight content of tomato flakes shall be at least 93 %.3. Thecontentofmineralandvegetableimpuritiestogethershallnot
exceed 1 % by weight of the product. For this purpose, ‘vegetableimpurities'means plant material visible by the naked eye which is notpartofthetomatoitselforwhichhasbeenattachedtothefreshtomatobut should have been removed during processing, in particular tomatoleaves, stalks, calyx bracts.
4. As an additive in the manufacture of tomato flakes only silicon
dioxide (551) may be used. However, the silicon dioxide content shallnot exceed 1 % by weight.
5. The mould count of tomato flakes shall, when homogenized in
watertoreach8%dryweightcontent,notexceed70%positivefields.
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TITLE IV
Requirements as to containers and verification
Article 13
1. Containers with preserved ►M1peeled and unpeeled toma-
toes◄,wholeornon-whole,andtomatojuiceshallbemarkedwitha
referenceidentifyingthedateandyearofproductionandtheprocessor.Incaseswheretomatojuiceprocessedondifferentdateshasbeenstoredtogetherbeforepacking,themarkingshallallowidentificationofalltheproduction dates.
2. The provisions of paragraph 1 shall also apply to other tomato-
based products when such products at the moment of processing arepackedinthecontainerinwhichtheyareintendedtoleavetheproces-sor’s premises. In cases where such products are stored in tanks orsimilar containers for subsequent packing or reprocessing, the date ordates of production shall be indicated on the containers. When suchproducts are packed in their ultimate containers, these containers shallbear a reference allowing identification of the production date or datesand the processor.
3. The marking referred to in this Article may be in code form and
shall be approved by the competent authorities in the Member Statewhere production takes place. These authorities may adopt additionalprovisions as to the marking itself.
Article 14
Theprocessorshalldailyandatregularintervalsduringtheprocessing
period verify that the products comply with the requirements for eligi-bility from aid. The result of the verifications shall be recorded.
Article 15
1. The methods of analysis for determining:
(a) dry weight content;(b) natural soluble solids;(c) salt content;(d) sugars content;(e) total acidity;(f) volatile acidity;(g) mineral impurities content;(h) pH level;(i) calcium ion content; and(j) silicon dioxide contentare laid down in the Annex.
2. Mould count shall be determined in accordance with the AOAC
(Association of Official Analytical Chemists) method (Howard mouldcount).
3. The methods referred to in paragraphs 1 and 2 shall be used for
definitive determination of the elegibility for production aid. Othermethods may be used for routine analysis.
Article 16
This Regulation shall enter into force on 1 July 1986.
ThisRegulationshallbebindinginitsentiretyanddirectlyapplicablein
all Member States.
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ANNEX
DRY WEIGHT CONTENT
1.Principle
The dry weight content means the total content of natural solids (NTS).The total content of natural solids, both soluble and insoluble, is deter-
mined by gravimetry after drying the product at 70 °C in a vacuum.
2.Apparatus
2.1. Goodqualityvacuumovenhavingauniformheatdistribution(70 °C±1
°C)andinwhichavacuumcanbemaintainedforseveralhoursafterthe
pump has stopped.
2.2. Laboratory vacuum pump capable of maintaining a pressure in the oper-
ating oven of less than 25 mm Hg if necessary.
2.3. Air-drying installation.
A gas purifier containing sulphuric acid must be connected to the air-
intake aperture of the oven.
2.4. Water bath.2.5. Flat-bottomed dishes with airtight lids, preferably 6 cm in diameter.2.6. Analytical balance accurate to 0,1 mg.2.7. Desiccator containing silica gel indicator.2.8. Kieselguhr washed with acid.2.9. Air-circulation oven operating at 110 °C.
3.Procedure
3.1. Placeabout15mgofkieselguhrpercm
2ineachdish(about0,4gineach
6-cm-diameter dish).
3.2. Drythedishes,withlidsremoved,inanair-circulationovenoperatingat
110 °C for at least 30 minutes.
3.3. Replace the dish lids, cool in a desiccator and weigh.3.4. Remove the dish lids and quickly place an appropriate quantity of well-
mixedsampleinthedishes.Replacelidsandweighasquicklyaspossible.Theweightofthesamplemustbebetween9and20mgoftotalsolidspercm
2of the surface area at the bottom of the capsule.
3.5. Remove the lid, stir the sample and the kieselguhr together using a glass
rod and add distilled water until a homogeneous sludge is uniformlyspread over the bottom of each dish. Wash the glass rod with distilledwater.
3.6. Bringthesampletoapparentdryness(residualmoisturecontentlessthan
50 % of dry weight content) using one of the following methods:
3.6.1. Placethedishesonawaterbothcontainingboilingwateruntiltheresidue
solidifies, turns a pinkish colour and begins to reach apparent dryness.
3.6.2. Place the dishes in a forced-airflow oven operating at 70 °C. The oven
must have a sufficiently rapid circulation of air inside it and sufficientexchange with the air outside it to achieve rapid evacuation of moisture.Examinethedishesatintervalsof30minutesorlessandremovethemassoon as they reach apparent dryness.
3.6.3. Placethedishesinavacuumdryingovenat70 °C,withtheregulatingtap
partlyopentoenableairtoflowquicklythroughtheovenatapressureofnotlessthan310mmHg.Examinethedishesat30-minuteintervalsandremove them as soon as they reach apparent dryness.
3.7. Placethepartiallydriedsamplesinavacuumdryingoven,withthedishes
resting directly on the shelf.
Allow dry air to enter the oven, passing through the H
2SO4purifier at a
rate of two to four bubbles per second.
Dry the samples for four hours at 70 °C and at a pressure not exceeding
50 mm Hg.
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The oven temperature may be as low as 65 °C when drying begins, but
must rise to between 69 and 71 °C within the first hour.
3.8. Remove dishes from oven, quickly replace lids and cool in a desiccator.3.9. Weigh capsules as soon as they have cooled to room temperature (after
about 20 minutes).
4.Expression of results
Percentage of natural total solids
% NTS =weight of residue
weight of sample× 100
5.Natural total solids
Thenaturaltotalsolidcontentisdeterminedafterthechloridecontenthas
been determined and added salt has been deducted. The pre-existingnatural salt content is fixed arbitrarily a t2%o ft h e total solid content.
NATURAL TOTAL SOLUBLE SOLIDS
1.Definition
Natural total soluble solids (NTSS) determined by the refractometric
method:thesucroseconcentrationofanaqueoussolutionhavingthesamerefractive index as the product analyzed, under specified conditions ofpreparationandtemperature.Theconcentrationisexpressedinpercentbymass.
2.Principle
Arefractometerisusedtomeasuretherefractiveindexofatestsolutionat
20°C and this refractive index is then converted, using tables, into the
natural soluble solids content (expressed as sucrose). Alternatively, thenatural soluble solids content may be read directly on the refractometer.
3.Apparatus
Standard laboratory equipment, including:
3.1. Refractometer,havingagraduatedscaleshowingtherefractiveindexand
accurate to 0,0005. The refractometer must be set to show a refractiveindexof1,3330fordistilledwaterat20 °C.Itmustalsobeset,forprisms
or standard solution, to show a refractive index of 1,3920,
alternatively
3.2. Refractometer,havingagraduatedscaleshowingthepercentagebymass
ofsucroseandaccurateto0,1%.Therefractometermustbesettoshowasolublesolid(sucrose)contentofzerofordistilledwaterat20 °C.Itmust
also be set, for prisms or standard solution, to show a soluble solid(expressed as sucrose) content of 36 %.
3.3. A water-circulation system, enabling the prisms of the refractometer (3.1
or3.2)tobekeptataconstanttemperature(varyingbynomorethan0,5°C) of about 20 °C, which is the reference temperature (see 5.1).
3.4. A beaker of suitable capacity.
4.Procedure
4.1.Preparation of the test solution (
1)
The laboratory sample must be well mixed. Press part of the sample
through a non-absorbent gauze (or similar material) folded in four.Discard the first few drops of liquid and use the rest for analysis.
4.2.Analysis
Adjust the water circulation system (3.3) to operate at the required
temperature (between 15 and 25 °C) and set it in operation so that the
(1) If the products are thick or highly concentrated, it may not be possible to extract the
drops of liquid required for refractometric analysis. Under these circumstances theanalysis should not be carried out. Under no circumstances should the sample bediluted with water.
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prismsoftherefractometer(3.1or3.2)reachthesametemperature,which
must be kept constant to within 0,5 °C during the analysis.
Bringthetestsolution(4.1)toatemperaturesimilartothattobeusedin
theanalysis.Placeasmallquantityofthetestsolution(twoorthreedropsare sufficient) on the fixed prism of the refractometer (3.1 or 3.2) andimmediately adjust the movable prism. The field of vision must be suit-ably illuminated. A sodium vapour lamp may be used to obtain moreprecise results (particularly if the products are coloured or dark).
Move the dividing-line between the light and dark areas of the field of
visionsothatitcoincideswiththeintersectionbetweenthecross-hairsonthescaleandreadoffthevalueoftherefractiveindexonthepercentageby mass of sucrose according to the type of apparatus used (3.1 or 3.2).
4.3.Number of determination
Two determinations should be carried out on each sample.
5.Expression of results
5.1.Corrections
Iftheanalysishasbeencarriedoutatatemperatureotherthan20 °C±0,5
°C, the following corrections must be made:
(a) where the scale shows the refractive index (3.1) use the following
formula:
n
20D=nt
D= 0,00013 (t − 20)
where t is the temperature used for the analysis, in degrees Celsius;
(b) where the scale shows the percentage by mass of sucrose (3.2), the
result should be corrected using Table 1.
5.2.Procedure for calculating the soluble solids content
The soluble solids content, expressed as a percentage by mass, is calcu-
lated as follows:
5.2.1.Refractometer having a graduated scale showing refractive
indices
ReadfromTable2thepercentagebymassofsucrosewhichcorresponds
to the value obtained from 4.2, corrected, if necessary, by 5.1 (a). Thesolublesolidscontentisequaltothenumberthusfound.Theresultshouldbetakentobethearithmeticalaverageofthetwodeterminationsprovidedtheconditionsforrepeatability(see5.3)aremet.Expresstheresulttoonedecimal place.
5.2.2.Refractometer having a graduated scale showing percent-
ages by mass of sucrose
Thesolublesolidscontentexpressedasapercentagebymassofsucroseis
equal to the number found at 4.2, corrected where necessary by 5.1 (b).The result should be taken to be the arithmetical average of the twodeterminationsprovidedtheconditionsforrepeatability(see5.3)aremet.Express the result to one decimal point.
5.3.Repeatability
The difference between the results of two determinations carried out in
rapid succession by the same analyst must not exceed 0,2 g of solublesolid per 100 g of product.
6.Natural soluble solids
The natural total soluble solid content is determined after the chloride
contenthasbeendeterminedandaddedsalthasbeendeducted.Forevery1 % chloride, 1,13 degrees Brix or 0,0157 refractive index must besubtracted (at 20 °C). These corrections take account of the pre-existing
natural salt content, which is fixed arbitrarily at 2 % of the total solidcontent.
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Solublesolidcontentshownonthescalein%(mm)
Temperature °C
5101520304050
Refractiveindex Solublesolids(expressedassucrose)
n20
D %(m/m)TABLE 1
Correction of readings to be made when using a refractometer having a
scale showing the sucrose content, for temperatures other than 20 °C ± 0,5
°C
Correctionstobesubtracted
150,250,270,310,310,340,350,36
160,210,230,270,270,290,310,31
170,160,180,200,200,220,230,23
180,110,120,140,150,160,160,15
190,060,070,080,080,080,090,09
Correctionstobeadded
210,060,070,070,070,070,070,07
220,120,140,140,140,140,140,14
230,180,200,200,210,210,210,21
240,240,260,260,270,280,280,28
250,300,320,320,340,360,360,36
TABLE 2
Percentagebymassofsolublesolids(expressedassucrose)inrelationtothe
refractive index
1,3330 0
1,3344 1
1,3359 2
1,3373 3
1,3388 4
1,3404 5
1,3418 6
1,3433 7
1,3448 8
1,3463 9
1,3478 10
1,3494 11
1,3509 12
1,3525 13
1,3541 14
1,3557 15
1,3573 16
1,3589 17
1,3605 18
1,3622 19
1,3638 20
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Refractiveindex Solublesolids(expressedassucrose)
n20
D %(m/m)
1,3655 21
1,3672 22
1,3689 23
1,3706 24
1,3723 25
1,3740 26
1,3758 27
1,3775 28
1,3793 29
1,3811 30
1,3829 31
1,3847 32
1,3865 33
1,3902 35
1,3920 36
1,3939 37
1,3958 38
1,3978 39
1,3997 40
1,4016 41
1,4036 42
1,4056 43
1,4076 44
1,4096 45
1,4117 46
1,4137 47
1,4158 48
1,4179 49
1,4201 50
CONTENT OF SALT
1.Principle
Atestsampleoftheproductisdiluted.Anexcessoftitratedsilvernitrate
solution is then added. The excess is then standardized with a titratedsolutionofpotassiumthiocyanateinthepresenceofferricammoniaalum.
2.Preparation of the sample
2.1. Weigh out300
Rg of the product, where R is the total soluble solids
content.
2.2. Transferproducttoa200-mlvolumetricflask,usingdistilledwaterwhich
has been recently boiled and cooled.
Rinsetheweighingvesselwithdistilledwaterandtransfertherinsewater
to the volumetric flask. Make up to the mark with distilled water.
2.3. Shake well and filter the solution using a pleated filter.2.4. Transfer20mlofthefiltratetoa250-mlconicalflaskanddilutewith40
to 50 ml of distilled water
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3.The Charpentier-Volhard method
3.1.Reagents
3.1.1. Standard silver nitrate solution 0,1 N.3.1.2. Pure nitric aci d d = 1,4.
3.1.3. Saturated solution of ferric ammonium sulphate (NH
4Fe(SO4)2l2H2O).
3.1.4. Standard potassium thiocyanate solution 0,1 N.3.2.Apparatus
3.2.1. Analytical balance3.2.2. 200-ml conical flask3.2.3. Class ‘A'10-ml graduated pipette3.2.4. Class ‘A'20-ml graduated pipette3.2.5. 25-ml burette, Class ‘A' according to the ISO draft recommendation.3.3.Procedure
Add about 2 ml of reagent No 2 and 10 ml (measured with a graduated
pipette) of solution No 1.
Boil for five minutes, then cool.TitrateusingsolutionNo4untiltheliquidturnsapersistentpinkcolour,
after adding a few drops of solution No 3. An initial determination ismade using distilled water (white).
3.4.Expression of results
The difference between the used volumes of solutions No 1 and No 4
represents the volume of silver nitrate solution used to precipitate thechlorides present in the test sample, reduction made for white. 1 ml ofsilvernitratesolution0,1Ncorrespondsto0,00585gofsodiumchloride.Expresstheresultsingramsofsodiumchlorideper100goftheproduct.
Notethatthepre-existingnaturalsaltcontentisfixedarbitrarilya t2%of
the total solid content.
Natural chloride content (Cl
nat)=2( NT S—C l T)
100
where:
NTS=dry weight content,
ClT=total chlorides.
Added chlorides=ClT−C lnat.
CONTENT OF SUGARS
1.Principle
Usually between 40 and 60 % of the dry weight content in tomato
derivatives consists of reducing sugars, mostly glucose and fructose inroughly equal proportions. The natural sucrose content of tomatoes isnegligible.ThenaturalsugarcontentisdeterminedbytheLaneandEynonmethod without inversion. The Lane and Eynon method uses Fehling’ssolution.
2.Reagents
2.1.Copper sulphate solution
Dissolveindistilledwater34,639gofCuSO
4·5H2O,diluteto500mland
filter through glass wool or filter paper.
2.2.Alkaline solution of potassium sodium tartrate
Dissolve173gofpotassiumsodiumtartrate4H2O(Rochellesalt)with50
g of NaOH in water and dilute to 500 ml. Leave standing for two days,then filter through asbestos.
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2.3. Saturated solution of lead acetate.
2.4.Carrez solution
I. Aqueous solution of potassium ferrocyanide 15 %.
II. Aqueous solution of zinc acetate 30 %.
2.5. Aqueous solution o f 1 % methylene blue.
2.6. Saturated solution of Na2SO4(sodium sulphate) or sodium oxalate.
2.7. Solution o f 1 % phenolphthalein in alcohol.
2.8. Solution of NaOH 0,1 N (4 g NaOH in 1000 ml water).
3.Apparatus
3.1. Analytical balance.3.2. Filter paper for rapid filtration.3.3. 25-ml burette.3.4. Erlenmeyer conical flask.3.5. 10-ml pipette.3.6. Kohlrausch-type 200-ml volumetric flask.
4.Procedure
4.1. ForthedeterminationofsugarsintomatoderivativesusingtheLaneand
Eynon method, the quantity of the sample analyzed must be such that,afterclarificationanddilution,thesugarsolutionanalyzedmustcontainaquantity of sugar such that 10 ml of Fehling’s solution is completelyreduced by 25 to 50 ml of sugar solution. The sugar solution mustthereforecontainbetween105and205mgofinvertsugarper100mlofsolution, as shown in the Table.
Duringdetermination,themeasuredsugarsolutionisdilutedsothat32ml
arerequiredtoreduce10mlofFehling’ssolution:thisconcentrationfallsin the middle of the range given in the Table. The sugar solution thuscontains roughly 160 mg of invert sugar per 100 ml of solution.
4.2. Weighoutaquantityoftomatoderivativecorrespondingtoapproximately
150
Rg, where R is the NTSS (natural total soluble solids) content.
4.3. Transfer the test sample to a 200-ml round-bottom flask. Rinse the test
samplecontainerandtransfertherinsewatertotheflask:thenmakeuptothe mark using distilled water.
4.4. Remove 100 ml of this solution using a pipette and transfer to a 250-ml
volumetric flask.
4.5. Usingapipette,add4to5mlofsaturatedleadacetatesolution;continue
toaddthissolutioncarefully,twodropsatatime,untiltheliquidisclear.
4.6. Clarification should, however, preferably be obtained by adding 5 ml of
Carrez solution I and 5 ml of Carrez solution II.
4.7. After clarification, allow the liquid to stand for 15 minutes. Then add a
quantityofthesaturatedsolutionofsodiumsulphateorsodiumoxalateinorder to remove any excess lead acetate. If there is any excess leadacetate,theadditionofsodiumsulphateoroxalatesolutionwillproduceawhite precipitate.
4.8. Allow to stand for 15 minutes, then make up to the 250 ml mark with
distilled water. Shake well, then filter using folded filter paper. Transfersome of the clear filtrate to a 100-ml burette: this solution is now readyfor analysis.
4.9. Two determinations of the sugar content must be carried out:
(a)Test determination
Transfer10mlofamixtureofequalpartsofFehling’ssolutionsinto
a 200-ml to 250-ml Erlenmeyer flask placed on a wire mesh. (EqualquantitiesofFehling’ssolutionsAandBshouldbemixedtogetherafew minutes before the determination.) Using the burette, add about25 ml of the sugar solution. Boil for 15 seconds.
Addfurtherquantitiesofthesolutionevery10seconds,untiltheblue
colour becomes pale.
1986R1764 — EN — 01.07.1989 — 001.001 — 14
▼B
A
mlofsugarsolutionusedupB
InvertsugarfactorsC
mginvertsugarin100ml
solutionAddoneortwodropsofthemethyleneblueindicatorandcontinueto
add sugar solution until the indicator changes colour completely.
The boiling liquid turns reddish brown.
(b)Final determination
Place10mlofamixtureofequalpartsoftheFehling’ssolutionsina
200- to 250-ml Erlenmeyer flask, then add directly the quantity ofsugarsolutionwhichwasusedupduringthetesttitration,less0,5ml.Bring the mixture to the boil and simmer for exactly two minutes.Add one or two drops of methylene blue, then add the remainingsugarsolution,twoorthreedropsatatime,at10-secondintervalsforaboutoneminute,untilthebluecolouroftheindicatorturnsreddishbrown.
LetAbethequantityofsugarsolutionusedup,expressedin0,1ml.Asthisisanempiricalmethod,alltheinstructionsgivenabovemust
be followed rigorously.
5.Expression of results
The following Table should be used to calculate, from the number of ml
of sugar solution used up, the invert sugar content of the sugar solutionandofthequantityoftomatoderivativecontainedinthetestsample.Theformula for the calculation is as follows:
Total sugars in g per 100g of product =C×0.5
weight of sample
where C (column 3 of the Table) corresponds to the volume A of sugar
solution used up (column 1 of the Table).
If the invert sugar content (expressed as percentage by weight of tomato
derivative) is divided by the natural total soluble solids content (NTSS),the result is the invert sugar content per 100 g of soluble solids.
TABLE
mg of invert sugar per 10 ml Fehling’s solution
25,0 51,2 204,8
2 203,4
4 201,9
6 200,4
8 198,9
26,0 51,3 197,4
2 196,0
4 194,6
6 193,2
8 191,8
27,0 51,4 190,4
2 189,1
4 187,7
6 186,4
8 185,0
28,0 51,4 183,7
2 182,5
4 181,2
6 180,0
8 178,7
29,0 51,5 177,5
1986R1764 — EN — 01.07.1989 — 001.001 — 15
▼B
A
mlofsugarsolutionusedupB
InvertsugarfactorsC
mginvertsugarin100ml
solution
2 176,3
4 175,2
6 174,0
8 172,9
30,0 51,5 171,7
2 170,6
4 169,5
6 168,5
8 167,4
31,0 51,6 166,3
2 165,3
4 164,3
6 163,2
8 162,2
32,0 51,6 161,2
2 160,3
4 159,4
6 158,4
8 157,5
33,0 51,7 156,6
2 155,7
4 154,8
6 154,0
8 153,1
34,0 51,7 152,2
2 151,3
4 150,5
6 149,6
8 148,8
35,0 51,8 147,9
2 147,1
4 146,3
6 145,5
8 144,7
36,0 51,8 143,9
2 143,2
4 142,4
6 141,7
8 140,9
37,0 51,9 140,2
2 139,5
4 138,8
6 138,0
8 137,3
38,0 51,9 136,6
2 135,9
4 135,3
1986R1764 — EN — 01.07.1989 — 001.001 — 16
▼B
A
mlofsugarsolutionusedupB
InvertsugarfactorsC
mginvertsugarin100ml
solution
6 134,6
8 134,0
39,0 52,0 133,3
2 132,7
4 132,0
6 131,4
8 130,7
40,0 52,0 130,1
2 129,5
4 128,9
6 128,3
8 127,7
41,0 52,1 127,1
2 126,5
4 125,9
6 125,4
8 124,8
42,0 52,1 124,2
2 123,6
4 123,1
6 122,5
8 122,0
43,0 52,2 121,4
2 120,9
4 120,3
6 119,8
8 119,2
44,0 52,2 118,7
2 118,2
4 117,7
6 117,1
8 116,6
45,0 52,3 116,1
2 115,6
4 115,1
6 114,7
8 114,2
46,0 52,3 113,7
2 113,2
4 112,8
6 112,3
8 111,9
47,0 52,4 111,4
2 111,0
4 110,5
6 110,5
8 109,6
1986R1764 — EN — 01.07.1989 — 001.001 — 17
▼B
A
mlofsugarsolutionusedupB
InvertsugarfactorsC
mginvertsugarin100ml
solution
48,0 52,4 109,2
2 108,8
4 108,4
6 107,9
8 147,5
49,0 52,5 107,1
2 106,7
4 106,3
6 105,9
8 105,5
50,0 52,5 105,1
2
4
6
8
TOTAL TITRATABLE ACIDITY
1.Principle
Thetotalnaturalacidscontentoftheproductismeasuredbytitrationwith
a solution of sodium hydroxide and using potentiometry.
2.Reagents
2.1. Titrated sodium hydroxide solution 0,1 N, free from carbon dioxide.2.2. Buffer solutions with known pH values of about 8,0.2.3. Solution o f 1 % phenolphthalein in alcohol.
3.Apparatus
Standard laboratory equipment, including:
— potentiometer with glass electrode,
— mechanical or electromagnetic agitator,— analytical balance,— 50-ml beaker,— 200-ml graduated pipette,— 50-ml graduated pipette,— 25-ml burette — Class ‘A'according to the ISO draft recommenda-
tion.
4.Procedure
Weigh into a 50-ml beaker a quantity of product corresponding to
300
R
g, ± 0,01 g where R represents the NTSS (natural total soluble solids)
content.
Transferthesampletoa200-mlvolumetricflask.Makeupto200mlwith
boiled distilled water. Shake well. Filter. Remove 50 ml of filtrate andtransfertoasquatbeaker(400-mlminimumcapacity).Addbetween150and 200 ml of boiled distilled water.
Using buffer solutions with pH values of about 8,0, check that the
potentiometerisfunctioningcorrectly.Usingtheburette,addthesodiumhydroxidesolution(2.1)fairlyquickly,whileshaking,untilthepHvalueis about 6,0. Add further solution slowly until the pH reaches 7,0. Thenadd further solution drop by drop, noting after each addition the volumeofsodiumhydroxidesolution(2.1)andthepHvalueuntilapHof8,1±
1986R1764 — EN — 01.07.1989 — 001.001 — 18
▼B
0,2 is reached. Deduce, by interpolation, the exact volume of sodium
hydroxide solution which corresponds to a pH value of 8,1.
At least two determinations must be carried out on the same prepared
sample.
5.Expression of results
The titratable acidity is expressed as monohydrated citric acid as
percentage of the dry weight content. 1 ml of sodium hydroxide solution(2.1) corresponds to 0,007 g of hydrated citric acid.
VOLATILE ACIDITY
1.Principle
Volatileacidsareremovedinastreamofwatervapourandtitratedinthe
distillate in the presence of phenolphthalein or by using a pH meter.
2.Reagents
2.1. Titrated solution of sodium hydroxide N/50 (0,02 N) freshly prepared
from a N/10 solution.
2.2. Solution of 0,05 % phenolphthalein in alcohol.2.3. Crystallized tartaric acid.2.4. Titrated solution of hydrochloric acid 0,1 N.
3.Apparatus
3.1. Special apparatus for removing acids in a stream of water vapour.3.2. Analytical balance.3.3. 10-ml burette graduated in twentieths of a millilitre.3.4. 200-ml conical flask.
4.Procedure
Fill the flask of the apparatus with about 1,5 litres of freshly boiled
distilled water. Add a few pieces of pumice stone. Weigh accurately, to
within 0,01 g, a quantity of product corresponding to
600
Rg,whereR
represents the NTSS (natural total soluble solids) content. After dilution
asnecessary,pourintotheinnertubeoftheapparatus.Addabout100mgofreagent2.3.Connecttheflasktothecondenser.Distil150mlinabout30minutes,collectingthedistillateina200mlconicalflask,withthetipof the condenser immersed in a small quantity of freshly boiled distilledwater.Stoptheprocedure.Pourafewdropsofphenolphthalein(2.2)intotheflaskandtitratetheacidityusingtheN/50sodiumhydroxidesolution(2.1)untiltheindicatorturnsapersistentpinkcolour.SinceN/50sodiumhydroxide solution is unstable, check the titre before use with an N/10solutionofhydrochloricacid(2.4).TitrationmayalsobemadebyusingapH meter.
5.Expression of results
Volatile acidity is expressed as acetic acid percentage of dry weight
content. One ml of N/50 sodium hydroxide solution (2.1) corresponds to0,0012 g of acetic acid.
MINERAL IMPURITIES
1.Principle
Heavyimpurities,generallyfromsoil(e.g.sand)butpossiblyalsopieces
of metal or high-density minerals, are separated on the basis of theirdensity. Organic matter is destroyed by burning at 500 to 600 °C. The
resulting residue is weighed.
1986R1764 — EN — 01.07.1989 — 001.001 — 19
▼B
2.Apparatus
Standard laboratory equipment, including:
2.1. Beaker, capacity 250 ml to 1000 ml.2.2. Dishes made of silica, porcelain or platinum.2.3. Ashless filters.2.4. Pear-shapedseparatingfunnel,2-litrecapacitywithwide-diametertap(see
figure).
2.5. Muffle furnace set at 500 to 600 °C.
2.6. Dryer.2.7. Analytical balance.
3.Procedure
Weigh into a beaker a quantity of product corresponding to
300
Rg, ±
0,01gwhereRrepresentstheNTSS(naturaltotalsolublesolids)content.
Add between 100 and 150 ml water. Mix well. Pour into the 2-litreseparating funnel, which should be partly filled with water, and set theadjustable tube so that its lower end is at least half-way down the bulb.Allow water to flow into the funnel at a rate that causes sufficientturbulencetoseparatethemineralsubstancesfromthepulp.Removethepulp in suspension without removing the sand; for this purpose theadjustable tube should be lowered towards the bottom of the separatingfunnel.
Continue the operation until only the mineral impurities remain at the
bottom of the funnel. Note that the residue may sometimes also containheavy organic waste such as tomato seeds.
Place the separating funnel over a funnel having an ashless filter and
strain all the residue through the filter opening the separating funnel tapand flushing out as necessary with water. Rinse the filter with distilledwater,thenplacethefilterpaperandresidueintheincineratingdish.Drythe dish, residue and filter, then char over a low flame and finallyincinerate in the muffle furnace at 500 to 600 °C for 30 minutes.
Allow to cool in the dryer and weigh accurately to within 0,0002 g.At least two determinations must be carried out on the sample. The
percentage by mass of mineral impurities is given by
(M
1—Mo)×100
E,,
where:
M0is the mass of the dish in grams,
M1is the mass of the dish and ash in grams,
E represents the dry weight content of the sample.
1986R1764 — EN — 01.07.1989 — 001.001 — 20
▼B
Diagram of apparatus used for continuous separation of water-insoluble
mineral impurities
pH
1.Principle
The pH of tomato derivatives is determined electrometrically using a pH
meter.
2.Apparatus
2.1. pH meter.
2.2. Reference and pH electrodes or combined electrode.2.3. Buffer solutions pH = 4,0 and pH = 7,0.
3.Procedure
3.1. Calibrate the pH meter using the buffer solutions.
3.2. Measure the temperature of the product using a thermometer and set the
instrument to that temperature.
3.3. Insert the electrodes or combined electrode into the undiluted tomato
product.
1986R1764 — EN — 01.07.1989 — 001.001 — 21
▼B
4.Expression of results
The pH is shown directly by the apparatus.
CALCIUM-ION CONTENT
1.Principle
The calcium content is determined by atomic absorption spectrophoto-
metry on a sample prepared beforehand.
Topreventpartialionizationoftheelementsintheflame,addlanthanum
for the quantity analysis of the calcium.
2.Reagents
2.1. Extra-pure 65 % nitric acid.2.2. Reference solution containing 1 mg/ml calcium.2.3. 5 % lanthanum solution.
Dissolve134glanthanumchloride(LaCl
3·7H2O)indouble-distilledwater
and bring volume to 1000 ml.
2.4. Extra-pure concentrated sulphuric acid (D = 1,84).
3.Apparatus
3.1. Atomic absorption spectrophotometer.3.2. Platinum dishes, diameter 10 cm, height 3 cm, flat-bottomed.3.3. Muffle furnace and hot plate.3.4. Infra-red lamp.3.5. Decontaminated glassware (calcium-free).
4.Procedure
4.1.Introductory remarks
Special care must be taken to ensure cleanliness of the vessels used.
Glassware must be rinsed beforehand with double-distilled water.
All solutions and all dilutions must be prepared with double-distilled
water.
For dilution, samples must be at least 1 ml.In each series of measurements, establish the calibration values with
appropriate solutions.
For quantity determination by absorption spectrometry, carefully adjust
the apparatus to the optimum wavelength.
If the various stages of the procedure to be followed are carried out in
differentlaboratories(e.g.preparationlaboratoryandmeasurementlabora-tory), it is vital that the same batch of double-distilled water is used todilute the solutions for analysis and standard solutions.
4.2.Mineralization of the sample
4.2.1.Digestion in the wet stage
Weigh out 1 t o2go ft h e homogenized sample, according to presumed
quantity of calcium, into a Kjeldahl flask.
Inthecaseofliquidproducts,weighout10gandconcentratedowntoa
reduced volume (2 to 3 ml).
Add 10 ml concentrated nitric acid (2.1) and 2,5 ml sulphuric acid (2.4).Start heating very gently until white fumes appear.At that point the solution should be clear and colourless.Ifthisisnotso,carefullyaddafewdropsofnitricacid(2.1)andcontinue
heating until white fumes appear.
Oncedestructioniscomplete,decantthesolutionwhichshouldbereduced
to 2 to 3 ml into a 25 ml volumetric flask and make up to volume withdouble-distilled water.
1986R1764 — EN — 01.07.1989 — 001.001 — 22
▼B
Samplespreparedinthisfashionareanalyzedandcomparedwithstandard
10 % sulphuric acid solutions (2.4).
4.2.2. Dryashing
Weighout5to10gofsample,accordingtoassumedquantityofcalcium,
into a platinum dish (3.2).
Dryinmufflefurnaceoronhotplaceorunderinfra-redlamp,onagentle,
slow heat to avoid losing matter through boiling over. Place residue inmuffle furnace preheated to 400 °C and incinerate for at least six hours.
Ifcadmiumispresent,afewdropsofphosporicorsulphuricacidshould
be added.
Iftheashisnotcompletelywhite,itshouldbewettedwithafewdropsof
nitric acid, the product should be dried completely under the infra-redlamp until there are no more white fumes, and treatment in the mufflefurnace should be repeated for at least four hours.
Mix the ash with 1 ml nitric acid, transfer to the 50 ml volumetric flask
and make up to the mark with water.
4.3.Direct determination
Quantities may be measured directly without mineralizing the sample in
the case of liquid products (juice or diluted concentrate).
Determinethequantityofthecalciuminthepresenceof0,5%lanthanum
by diluting the original solution (2.3).
4.4.Determination
Dilute sample solutions so that the concentration of the calcium to be
analyzed falls within the concentration range of the calibration curve.
Calcium: λ= 422,7 mm
Flame: air/acetyleneCorrective coefficient for background noise
4.5.Preparation of calibration curve
Takefour10-mlvolumetricflasksandpour1mlconcentratednitricacid
and 1 ml 5 % lanthanum solution (2.3) into each.
Pour0,1,3and5mlrespectivelyofa10-ppmcalcliumsolutionintothe
flasks and make up to the mark with double-distilled water.
Determine the absorbance of each solution and plot the calibration curve
after subtracting the blank value from the standards.
5.Calculations
The calcium content is calculated from the corresponding calibration
values determined during each series of measurements, taking dilutionfactors into account.
6.Precision of the Method
Repeatability (r):Calcium: r = 1,1 + 0,029 x
img/l.
Reproducibility (R):Calcium: R = 2,2 + 0,116 x
img/l.
xi= measured concentration.
SILICONE OXIDE CONTENT
1.Procedure
Weigh out 10 g tomato powder or flakes to within 0,01 g into a 300-ml
beaker. Add 200 ml water. Mix well. Leave to settle for 10 minutes.Carefully pour off supernatant. Repeat the operation a second time.Collect solid residue on an ashless ultra-fast filter. Roast in a porcelainincinerationdish.Ifnecessary,mixwithalittledistilledwaterandreturnto furnace until the ash is white.
1986R1764 — EN — 01.07.1989 — 001.001 — 23
▼B
Mixwith10cm3nitricacid(d=1,4)dilutedtohalf.Heatverygentlyand
collect precipitate on an ashless pleated filter, dry and roast in a taredcrucible (m °). If necessary mix as before with a little distilled water and
roast once more if ash is not white. Weigh crucible (m).
2.Calculations
(m − m °) × 10 = percentage of silicon oxide in the powder.