Sortex cleaning
— definition for Pakistani agri exporters.

Definition

Sortex cleaning — also known as colour sorting or optical sorting — is an automated process in which a stream of granular material (whole spices, seeds, grains, pulses) flows past a high-speed camera array. The camera analyses each particle's colour, shape and structural signature in real time; off-spec particles (discoloured grains, foreign matter, husk, immature seeds, stones, glass, plastic) are identified and ejected from the stream by precision air-jet nozzles. The accepted product continues to the bagging line.

The name "Sortex" derives from Bühler Sortex, the UK-based equipment manufacturer (now part of Bühler Group) that pioneered the technology. The term has become a generic industry shorthand in South Asia for any optical-colour-sorting line, regardless of equipment brand (Tomra, Anysort, Daewon, Buhler, etc. all build comparable machines).

Why it matters for Pakistani exporters

For Pakistani spice and seed exporters, Sortex cleaning is the difference between commodity-tier and premium-tier product. After conventional cleaning (gravity, sieve, destoner, magnet, metal detector), residual defects — discoloured fenugreek seeds, broken or off-colour cumin, immature coriander, foreign weed seeds — typically make up 1-3% of the lot. Sortex passes reduce this to 0.1-0.3%.

Premium-grade specifications for export — to EU, USA, Japan, GCC retail private-label, pharma/nutraceutical raw material — almost always require Sortex-cleaned product. The visible quality difference also commands a 5-15% price premium over machine-cleaned-only product, and reduces buyer-side rejection rate.

Practical guidance

Typical Sortex spec for Pakistani spice and seed exports:

• Fenugreek seeds — Sortex purity ≥ 99.7%, foreign matter < 0.3%, discoloured seeds < 0.5%.
• Cumin seeds — Sortex purity ≥ 99.5%, foreign matter < 0.5%, immature seeds < 0.5%.
• Coriander seeds — Sortex purity ≥ 99.5%, husk and broken < 0.5%.
• Sesame seeds (white/black) — Sortex purity ≥ 99.95%, foreign matter < 0.05% (extremely tight for confectionery and bakery applications).
• Whole dried chillies — Sortex less common (size sorting more typical); some processors use Sortex on stem-removed crushed chilli.

Sortex passes: single-pass for commodity grade, double-pass for premium, triple-pass for Japanese/EU pharma grade. Each pass adds processing cost (~USD 30-80/MT).

Source & standards reference

Reference: equipment standard from Bühler Sortex / Bühler Group, buhlergroup.com, and competing optical sorters from Tomra Food, Daewon GSI, Anysort. Pakistani industrial implementation typically follows FSSAI / Codex Alimentarius spice-purity specifications.

Related glossary entries