Tiêu chuẩn iso 01575 1987 scan

INTERNATIONAL STANDARD INTERNATIONAL ORGANKATION FOR STANDARDIZATIOM ORGANISATION INTERNATIONALE DE NORMALISATION lvlEX)JYHAPO~HAR OPTAHM3A~Mfl l l0 CTAHflAPTL1 3A~MM Tea Determination of total ash TM[.]

INTERNATIONAL STANDARD

INT R A T IONA L ORGA NK A TION FOR STA NDA RDIZA TIO

ORGA IS T ION INT R A TION L DE NORMA LIS T ION

lvlEX)JY HA O~H R OPTA M3A~Mfl l-l0 CTA flA PT 13A ~M

T M -

Determin tio d s ce dres totales

T hir d edition

19 7-10-01

Refere ce numb r

ISO (h Intern tio al Org nizatio for Sta d rdizatio ) is a worldwid fe eratio of

n tio al Sta d rds b dies (ISO memb r b dies) Th work of pre arin Intern tio al

Sta d rds is n rmaly carie out throug ISO tech ical com ite s Es h memb r

b dy intereste in a s bject for which a tech ical commite h s b e esta lsh d h s

th rig t to b re rese te o th t commite Intern tio al org nizatio s, g v rn-

me tala d n n-g v rnme tal in laiso with ISO, also tak e p rt in th work

Draf Intern tio al Sta d rds a o te by th tech ical commite s are circ late to

th memb r b dies for a pro al b fore th ir ac e ta ce as Intern tio al Sta d rds by

th ISO Counci Th y are a pro e in ac ord nce with ISO proce ures re uirin at

le st 7 % a pro al by th memb r b dies v tin

Intern tio al Sta d rd ISO 15 5 was pre are by Tech ical Com ite ISO/TC 3 ,

Agric ltural fo d pro u ts

This third e itio ca cels a d re laces th seco d e itio (ISO 15 5 : 19 01, of which it

co stitutes a min r re isio

Users sh uld n te th t al Intern tio al Sta d rds un erg re isio from time to time

a d th t a y refere ce ma e h rein to a y oth r Intern tio al Sta d rd imples its

latest e itio , unles oth rwise state

0

Inter natio al Or gan atio f or Stan ar dkatio , 19 7

Tea - Deter mination of total ash

This Intern tio al Sta d rd sp cifies a meth d for th d termi-

n tio of th total ash from te

2 Refer en es

ISO 15 2, Te -

Pre aratio of groun Sample of k nown dry

mater co te t

ISO 15 6, Te -

Determin tio of water-soluble asb a d

wa ter-insoluble ash

ISO 15 7, Te - Determin tio of acid-insoluble ash

3 Def i ition

For th purp ses of this Intern tio al Sta d rd, th folowin

d finitio a ples

total ash

5 5 + 2 O un er th co ditio s sp cifie in this Inter-

n tio al Sta d rd

4 Pr i ciple

Destru tio of org nic mater by h atin at 5 5 + 2 O to

co sta t mas

5 A pp r atu

Us al la oratory a p ratu , a d th folowin items :

5.1 Dish, of ca acity 5 to 10 ml ma e of platinum, p rce-

lain or oth r material un fecte by th co ditio s of th test

NOT - It is c n id r ed t h sica dis e ar e u s ita le f or u e w ith

this te t

5.2 Furn ce, ca a le of b in co trole at 5 5 + 2 O

5.3 Ste m b th

5.4 Hotplate

5.5 Desic ator, co tainin a ef icie t d sic a t

5.6 An lytical b la ce

Use a groun Sample of k nown dry mater co te t, pre are as

sp cifie in ISO 15 2

7 Pr oced r e

He t th dish (5.1) for 1 h in th furn ce (5.2) at 5 5 + 2 O

Co l in th d sic ator (5.5) Afer co ln , weig to th n arest

0,0 1 g

7.2 Test Portio

Weig , to th n arest 0,0 1 g, a out 5 g of th groun Sample

into th pre are dish (7.1) (Se ISO 15 2.)

7.3 Determin tio

7.3.1 He t th test Portio in th dish, at a temp rature n ar

10 O unti th moisture is exp le Tra sfer th dish to th

furn ce (5.2) a d h at at 5 5 rt 2 O unti th ash is visibly

fre from carb n p rticles (at le st 2 h is u ualy re uire )

Alow to co l th n moiste th ash with disti e water, dry it

o th ste m b th (5.3) a d th n o th h tplate (5.4) Return

th dish to th furn ce for 6 min, co l in th d sic ator a d

weig He t a ain in th furn ce for 3 min, co l a d weig

Re e t th se o eratio s,

if n ces ary, unti th difere te

b twe n two s c es iv weig in s d es n t ex e d 0,0 1 g

7.3.2 Reserv th total ash for d termin tio of water-soluble

asb a d water-insoluble ash (se ISO 15 6), or of acid-insoluble

ash (se ISO 15 71, if re uire

7.4 Numb r of d termin tio s

Cary out two se arate d termin tio s o th same groun

Sample (clau e 6)

8 Expr es ion of r es lts

Th total ash yield d by th groun Sample, expres e as a p r-

ce ta e by mas o th dry b sis, is giv n by th formula

rnl x - x -

wh re

m is th mas , in grams, of th test Portio ;

ml is th mas , in grams, of th total ash;

RS is th dry mater co te t, as a p rce ta e by mas , of

d termin d in ac ord nce with

ISO 15 2

Tak e as th res lt th arithmetic me n of th two d termin -

tio s, pro id d th t th re uireme t for re e ta i ty (se 8.2) is

satisf ie

8.2 Re e ta i ty

Th difere te b twe n th res lts of two d termin tio s, car-

rie out simulta e u ly or in ra id s c es io by th same

a aly t, sh l n t ex e d 0,2 g of total ash p r 10 g of groun

Sample

9 T est r ep r t

Th test re ort sh l sh w th meth d u e a d th res lt

o tain d lt sh l also me tio a y o eratin d tais n t sp ci-

fie in this Intern tio al Sta d rd, or re ard d as o tio al as

w el as a y circ msta ces th t may h v influe ce th res lt

T he re ort sh l includ al d tais re uire for complete id ntifi-

catio of th Sample

De c ptors :

agric ltur al pr od cts, tea, te ts, as d ter minatio

Pric b s d o 2 pg s