SIST ISO 6636-2:1995 PDF

Name: SIST ISO 6636-2:1995 — Fruits, vegetables and derived products -- Determination of zinc content -- Part 2: Atomic absorption spectrometric method
SKU: SIST ISO 6636-2:1995
Price: 43.71 EUR
Availability: InStock

Fruits, vegetables and derived products -- Determination of zinc content -- Part 2: Atomic absorption spectrometric method

Название (английский):

SIST ISO 6636-2:1995

Fruits, vegetables and derived products -- Determination of zinc content -- Part 2: Atomic absorption spectrometric method

Статус документа:: Действующий
Формат:: Электронный (PDF)
Количество страниц:: 6
Дата публикации:: 1 марта 1995 г.
ICS:: 67.080.01
Технический комитет:: KŽP - Agricultural food products

Тип поставки:

Full version90 €Read online 24h10 €Read online 72h15 €

Язык документа:

ruen

Срок поставки:1 раб. дн. (перевод)

Цена:90 €

Описание (английский):

The method consists is decomposing of organic matter by a dry or wet method and determing of the Zn + cation by a suitable spectrometer. For some liquid samples the determination may be carried out directly, without previous decomposition.

Abstract

Похожие стандарты

Стандарты, упомянутые в описании

Overview

ISO 6636-2:1981 - "Fruits, vegetables and derived products - Determination of zinc content - Part 2: Atomic absorption spectrometric method" specifies an atomic absorption spectrometry (AAS) procedure for measuring zinc (Zn2+) in fruits, vegetables and derived food products. The method covers sample preparation (dry ashing or wet digestion), instrument measurement (air–acetylene flame AAS at 213.8 nm) and reporting requirements. For some clear liquid samples (wines, clear juices) direct measurement without prior decomposition is permitted.

Key topics and technical requirements

Scope: Determination of zinc content in fruits, vegetables and derived products using AAS.

Sample preparation

Dry method: ashing (muffle furnace) followed by dissolution of ash in hydrochloric/nitric acid.
Wet method: acid digestion with nitric and sulfuric acids in Kjeldahl flasks; recommended sample masses: 5–10 g for pasty/solid products; 10 mL for liquid samples.
For viscous/heterogeneous samples, appropriate homogenization and representative test portions are specified.

Reagents and standards

All reagents must be of analytical purity and free of zinc; use double-distilled or equivalent water.
Zinc standard solution: a 1 g Zn per litre stock is prepared and used to make calibration standards.
Specific acid solutions (HNO3, H2SO4, HCl) and a dilute HCl solution for dilutions are detailed.

Apparatus

AAS with air–acetylene burner, set for optimum aspiration and wavelength 213.8 nm.
Muffle furnace controllable at 525 ± 25 °C; electrically heated oven; centrifuge; volumetric flasks (50 mL); platinum or quartz dishes or Kjeldahl flasks; analytical balance.

Calibration and measurement

Calibration curves produce standards in the range 0.25–1.5 mg Zn/L (prepared differently depending on decomposition method).
Blank test required; blank absorbance must be ≤ 0.002.
If sample absorbance exceeds the highest calibration point, dilute appropriately and apply dilution factor.

Performance

Repeatability: difference between two determinations by the same analyst on the same sample should not exceed 10% (relative).

Reporting

Report method used, result and expression (per litre, per kg, or dry basis), and any deviations or incidents.

Applications and users

Laboratories performing nutritional analysis, food safety testing, regulatory compliance and quality control for:

Fresh and processed fruits and vegetables
Fruit juices, wines and other derived products
Dried, pasty and viscous products

Stakeholders: food testing labs, producers, regulatory agencies, research institutions and accreditation bodies.

Related standards

ISO 5515 - Decomposition of organic matter prior to analysis - Wet method

ISO 5516 - Decomposition of organic matter prior to analysis - Ashing (dry) method

Keywords: ISO 6636-2:1981, zinc determination, atomic absorption spectrometric method, fruits and vegetables, AAS 213.8 nm, sample digestion, food analysis, calibration graph.

SIST ISO 6636-2:1995 PDF

Abstract

Похожие стандарты

Overview

Key topics and technical requirements

Applications and users

Related standards

Технические детали

ISO 6636-2:1981

Fruits, vegetables and derived products — Determination of zinc content — Part 2: Atomic absorption spectrome…

SIST ISO 5515:1995

Fruits, vegetables and derived products -- Decomposition of organic matter prior to analysis -- Wet method

ISO 5516:1978

Fruits, vegetables and derived products — Decomposition of organic matter prior to analysis — Ashing method