SIST EN ISO 11213:1998 PDF

Name: SIST EN ISO 11213:1998 — Modified starch - Determination of acetyl content - Enzymatic method (ISO 11213:1995)
SKU: SIST EN ISO 11213:1998
Price: 51.9 EUR
Availability: InStock

Modified starch - Determination of acetyl content - Enzymatic method (ISO 11213:1995)

Название (английский):

SIST EN ISO 11213:1998

Modified starch - Determination of acetyl content - Enzymatic method (ISO 11213:1995)

Статус документа:: Действующий
Формат:: Электронный (PDF)
Количество страниц:: 11
Дата публикации:: 1 ноября 1998 г.
ICS:: 67.180.20
Технический комитет:: KŽP - Agricultural food products

Тип поставки:

Full version165 €Read online 24h10 €Read online 72h15 €

Язык документа:

ruen

Срок поставки:2 раб. дн. (перевод)

Цена:165 €

Описание (английский):

Applies to modified starch, both granular and soluble in cold water. The methods specified enable to measure total and free acetyl contents; bound acetyl content is calculated as the difference of the two values. Total content is determined by heating the sample with dilute hydrochloric acid and converting the acetate with adenosine-5-triphosphate (ATP) and coenzyme A (CoA) to acetyl-CoA. The methods are suitable for determining acetyl contents up to 2 % (m/m).

Abstract

Похожие стандарты

Стандарты, упомянутые в описании

Overview

EN ISO 11213:1995 - "Modified starch - Determination of acetyl content - Enzymatic method" describes a validated laboratory procedure for quantifying acetyl content in modified starch (both granular and cold‑water soluble). The method measures total and free acetate; bound acetyl is obtained by subtraction. It is suitable for acetyl contents up to 2% (m/m) and uses enzymatic conversion to generate NADH, measured spectrophotometrically at 340 nm.

Key topics and technical requirements

Scope: Applies to modified starch and starch derivatives (granular or cold‑water soluble).

Principle: Hydrolyse acetyl groups with dilute HCl to release acetate; convert acetate to acetyl‑CoA using adenosine‑5'‑triphosphate (ATP) and coenzyme A (CoA) in the presence of acetyl‑CoA synthetase (ACS). Subsequent enzyme reactions (malate dehydrogenase, citrate synthase) produce NADH; increase in absorbance at 340 nm is proportional to acetate concentration.

Free vs. total acetyl: Free acetate is determined from an aqueous extract/filtrate of dispersed starch. Total acetyl requires acidic hydrolysis and solubilization prior to enzymatic assay. Bound acetyl = total − free.

Analytical conditions: Typical temperature control (20–25 °C), cuvette path length 10 mm, molar absorption coefficient of NADH at 340 nm (6.30 L·mmol−1·cm−1).

Sample prep: Sieve (800 µm), grind if necessary, homogenize; correct results for moisture.

Reagents and apparatus: Analytical‑grade reagents, MDH/CS and ACS enzyme preparations, ATP/CoA/NAD reagent mix, spectrophotometer at 340 nm, boiling water bath for hydrolysis.

Performance/precision: Method precision established by interlaboratory study; repeatability and reproducibility criteria are specified (repeatability: within 5% of higher result; reproducibility: within 8% of higher result). Refer to Annex B for statistical details.

Applications and users

Quality control in starch manufacturing and food ingredient production

Product specification testing for acetylated starches used in food, feed, paper, and pharmaceutical formulations

R&D and process validation where acetylation level affects functionality (e.g., thickening, stability, film properties)

Regulatory and certification laboratories validating conformity to product standards

Related standards

ISO 3696 - Water for analytical laboratory use

ISO 1666 - Starch - Determination of moisture content

ISO 5725 - Precision of measurement methods and results

Keywords: EN ISO 11213:1995, modified starch, acetyl content, enzymatic method, acetyl measurement, acetyl‑CoA synthetase, NADH 340 nm, bound acetyl, free acetate.

SIST EN ISO 11213:1998 PDF

Abstract

Похожие стандарты

Overview

Key topics and technical requirements

Applications and users

Related standards

Технические детали

ISO 11213:1995

Modified starch — Determination of acetyl content — Enzymatic method

SIST EN ISO 3696:1998

Water for analytical laboratory use - Specification and test methods (ISO 3696:1987)

SIST EN ISO 16664:2017

Gas analysis - Handling of calibration gases and gas mixtures - Guidelines (ISO 16664:2017)

ISO 5725-6:1994/Cor 1:2001

Accuracy (trueness and precision) of measurement methods and results — Part 6: Use in practice of accuracy va…