BS 5752-10:1986 Methods Of Test For Coffee And Coffee Products – Part10:Instant Coffee: Size Analysis.
1 Scope and field of application
BS 5752-10 specifies a method for the determination of the particle size (screen) analysis of instant coffee, by manual or mechanical sieving, using test sieves.
2 References
ISO 2591, Test sieving.
ISO 33 10-1, Test sieves — Technical requirements and testing — Part 1: Test sieves of metal wire cloth.
ISO 3509, Coffee and its products — Vocabulary.
ISO 6670, Instant coffee in cases with liners — Sampling.
3 Definitions
For the purpose of this International Standard, the
definitions of ISO 3509 apply.
4 Principle
Separation of a test portion into fractions according to particle size, by manual or mechanical sieving, and expression of results as percentages by mass.
5 Apparatus
Usual laboratory apparatus, and in particular
5.1 Nest of test sieves, of diameter 200 mm, conforming to ISO 2591 and ISO 3310-1, together with a cover lid and receptacle pan. These sieves should be taken from one of the two series shown in the Table, preferably the R 20/3 series.
7.1 Choice of sieves
In the case of spray-dried instant coffee, choose a nest of four or five sieves from those with smaller sizes of openings, preferably in the R 20/3 series or the selected sizes from the R 40/3 series (see the Table).
In the case of freeze-dried or agglomerated instant coffee, choose a nest of four or five sieves from those with larger sizes of openings, preferably in the R 20/3 series or the selected sizes from the R 40/3 series (see the Table).
Nest the sieves and place the receptacle pan under the sieve having the smallest size of openings.
7.2 Test portion
Weigh, to the nearest 0,1 g, approximately 100 g of the laboratory sample.
7.3 Sieving and weighing
Pour the test portion (7.2) uniformly on the top sieve, and place the cover lid in position.