Purple Colour
Purple Colour
Mechotech designs and manufactures turnkey natural colour extraction plants for the purple colour group. In the Mechotech catalogue this group lists one raw-material entry, Vegetables - Purple sweet Potato / Purple potato / Purple corn / Red Cabbage. The catalogue treats purple colour as a group page rather than a single plant: the member page describes the raw materials. According to Mechotech’s article on purple colour extraction from vegetables, these vegetables are coloured by anthocyanins, water-soluble flavonoid pigments that appear red in strong acid, purple to violet at mildly acidic to neutral pH and blue to blue-green under alkaline conditions.
Mechotech’s purple colour plant is configured around the raw material chosen from the group and the target colour extract. It is built in SS 316L with integrated solvent recovery, automation and full documentation, and is delivered as a commissioned turnkey system. Because anthocyanin colour depends on pH, the article describes extraction and stabilisation techniques that hold the purple hue; the raw material, solvent, pH and temperature are selected during process development and pilot validation.
Technical Specifications
| Product | Purple Colour Natural Colour Extraction Plant |
|---|---|
| Raw Material | Selected from the group: Vegetables - Purple sweet Potato / Purple potato / Purple corn / Red Cabbage |
| Plant Part / Feed Form | Varies by raw material; confirmed with the client for the chosen material |
| Colour Group | Purple Colour |
| Extract Type | Natural colour extract (liquid concentrate or dried powder, per specification) |
| Extraction Method | Closed jacketed SS 316L extraction at controlled temperature with water or food-grade alcohol / aqueous solvent, pH-controlled for anthocyanin stability; route confirmed during process development |
| Product-contact Material | SS 316L |
| Filtration System | Plate-and-frame filter press with cartridge polish filters |
| Concentration System | Falling-film / vacuum evaporator with solvent recovery where a solvent is used |
| Drying System | Spray or vacuum dryer, where a powder is required |
| Automation | PLC-based |
| Plant Capacity | Configured to requirement |
| Utility Requirements | Steam, chilled/cooling water, compressed air and power (project-specific) |
| Compliance | GMP hygienic design; full documentation for qualification |
| Final Product Form | Natural colour extract (purple colour group) |
Plant Capacities
| Plant Scale | Raw Material Throughput | Typical Use |
|---|---|---|
| Pilot | Configured to your feedstock and trial plan | Product development, parameter validation |
| Semi-Commercial | Configured between pilot and commercial scale | Scale-up trials, contract manufacturing |
| Commercial | Configured to raw-material supply and confirmed buyer volume | Commercial production |
Capacity is configured to raw-material supply, confirmed buyer volume and investment timeline; a pilot plant is recommended to validate parameters before scaling.
Manufacturing Process
Raw Material Preparation
The vegetable chosen from the group is authenticated, washed, tested for moisture and cut or milled to open the tissue; the feed form (fresh, dried, or pressed material) is confirmed with the client.
Extraction
The prepared material is extracted in closed jacketed SS 316L vessels at controlled temperature over several cycles. The article describes the anthocyanin route and notes that the pH is the dominant factor in hue, so the pH is controlled to hold the purple hue; the solvent and conditions are set during process development.
Filtration
The extract is separated from the spent material and clarified through a plate-and-frame filter press followed by cartridge polish filters.
Concentration & Solvent Recovery
The extract is concentrated in a falling-film / vacuum evaporator, with solvent recovered through the condenser return system where a solvent is used. Vacuum concentration at moderate temperature protects the heat-sensitive anthocyanins.
Standardisation
The concentrate is assayed and adjusted to the declared target colour specification, such as shade and colour strength, with the raw material and pH held consistent between batches.
Drying & Quality Control
The standardised extract is supplied as a liquid concentrate or spray- or vacuum-dried to a powder, per specification, then released after assay, residual-solvent (where a solvent is used), heavy-metal, microbial and moisture testing.
Major Plant Equipment
- Raw material cleaning, authentication and moisture testing
- Size-reduction system
- Closed jacketed SS 316L extraction vessels
- Solvent storage tanks
- Plate-and-frame filter press
- Cartridge polish filtration
- Falling-film / vacuum evaporator
- Solvent recovery unit and condensers
- Standardisation / blending vessel
- Spray or vacuum dryer
- CIP system
- Automation and instrumentation
Plant Output
Applications
- Natural purple colour and dye ingredient supply
- Food and beverage colour applications (subject to approval of the specific colour in each market)
- Cosmetic and personal-care colour applications
- Textile colouring (the article names textiles among the markets)
Key Features
SS 316L Construction
Electropolished SS 316L product-contact surfaces with CIP operation between batches.
pH-Controlled Hue
The article notes anthocyanins are red in strong acid, purple to violet at mildly acidic to neutral pH and blue under alkaline conditions, so pH is controlled through extraction and stabilisation.
Gentle Concentration
Vacuum concentration at moderate temperature protects the heat-sensitive anthocyanins.
Standardised to Specification
In-process and batch-release assay are used to check the finished extract against the agreed target specification, such as shade and colour strength.
Scalable Batch Capacity
Plants are configured to requirement from pilot scale upward, with modular expansion.
Frequently Asked Questions
Does Mechotech supply the complete machinery for Purple Colour?
What specification can the Purple Colour plant achieve?
What production capacities are available for the Purple Colour plant?
Which industries use the Purple Colour plant?
Which raw materials are in the Purple Colour group?
What gives these vegetables their purple colour?
Why does the purple shift with pH?
How is the raw material chosen?
Which related colour pages does Mechotech list?
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