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Spice cleaning, sterilising and grinding
Cleaned whole spice, steam-sterilised spice, ground powder, blends, oleoresin feedstock
Spice cleaning, sterilising and grinding line by GEM Foodtech, Kolkata, India — capacity 500 kg to 10 tonnes per hour, final yield 90.5% of raw intake, delivered as a turnkey plant with installation and commissioning worldwide.
The commercial reality
The export market does not buy spice on flavour alone; it buys on microbial count, pesticide residue and foreign matter. Steam sterilisation and cooled grinding are the two pieces of equipment that move a commodity into a specification product, and the price gap between the two is where the project pays for itself.
Process flow diagram
Generated for the standard configuration. Yours is redrawn to your product mix, capacity and site.
Process chart
Every stage with the equipment that performs it, the operating parameter and the control point that decides quality.
| # | Stage | Equipment | Parameter | Control point |
|---|---|---|---|---|
| 01 | Pre-cleaning | Grader and size sorter | Destoner, aspirator, magnet | Stone, dust and metal removed |
| 02 | Washing and drying, where applicable | Fruit and vegetable washer | Wash then belt dryer to 9–10% | Surface load and safe moisture |
| 03 | Steam sterilisation | Steam cooker and conditioner | Saturated steam, controlled hold and vacuum | Microbial reduction of 3–5 log |
| 04 | Conditioning | Fluid bed dryer and cooler | Cooling and moisture equalisation | Grinding moisture achieved |
| 05 | Grinding | Grinder and pulveriser | Cooled pin mill or cryogenic mill | Volatile oil retained |
| 06 | Sieving and classification | Vibro sifter and grader | 30–100 mesh | Particle size distribution |
| 07 | Blending | Tanks, kettles and blenders | Ribbon or plough blender | Blend uniformity |
| 08 | Packing | Filling, sealing and packing line | Metal detection, nitrogen flush | Shelf life and traceability |
Mass balance
Basis of 1,000 kg of raw material. Change the tonnage below and the whole table rescales.
| Stage | Output, kg/h | Yield | Loss, kg/h | Where the loss goes |
|---|---|---|---|---|
| Raw spice received | 1,000 | 100% | 0 | — |
| After pre-cleaning | 940 | 94% | 60 | Stone, dust and light trash |
| After sterilisation and conditioning | 930 | 93% | 10 | Moisture adjustment |
| Ground and sieved | 910 | 91% | 20 | Mill losses and oversize |
| Packed product | 905 | 90.5% | 5 | Packing losses |
By-products: Screenings and mill fines routed to oleoresin extraction rather than sold as sweepings.
Equipment schedule
Core machines for this line. Conveying, tanks, CIP and utilities are added to suit the layout.
| Equipment | Capacity range | Function |
|---|---|---|
| Grader and size sorter | Separation | Separates by size or specific gravity before or after processing. |
| Fruit and vegetable washer | Preparation | Removes field soil, latex and surface load with recirculated, filtered water. |
| Steam cooker and conditioner | Thermal | Steam conditioning ahead of shelling, flaking or drying. |
| Fluid bed dryer and cooler | Drying | Finishing and cooling of granular product to bagging temperature. |
| Grinder and pulveriser | Size reduction | Hammer, pin or cryogenic milling to a controlled mesh. |
| Vibro sifter and grader | Separation | Mesh separation into grades; oversize returns to the mill. |
| Tanks, kettles and blenders | Utility | Jacketed mixing, cooking, holding and batching in SS 304 or 316. |
| Filling, sealing and packing line | Packing | Weighing, filling, sealing, metal detection and case packing. |
Questions we get on this line
Why cryogenic grinding?
Volatile oils boil off in a normal mill because grinding generates heat. Liquid nitrogen keeps the product cold and holds the oil, which is what the buyer is paying for in pepper and cardamom.
Does steam sterilisation affect flavour?
Correctly controlled, minimally. It is now a standard requirement for EU and US buyers, and irradiation is rejected by many of them.
What capacity range does the spices line cover?
Standard GEM Foodtech builds cover 500 kg to 10 tonnes per hour. Larger duties are engineered to order — the right size is set by the raw material supply through the season, not the nameplate figure.
Is this supplied as a complete turnkey plant?
Yes. The Spice cleaning, sterilising and grinding line is delivered end to end — feasibility, pilot trial on your own material, engineering, manufacture in Kolkata, installation, commissioning and operator training — or as individual machines to fit an existing plant.
Want this line costed for your tonnage?
Send the raw material specification and the capacity you are targeting. You get a flow diagram, an equipment schedule and a budget number.