Processing
Primary processing & transformation
Processing is where a commodity stops being itself. Milling does not give you better wheat grain — it gives you flour, bran, and germ, three different things with three different markets. This section documents those transformations: what goes in, what comes out, and on what physical or biochemical basis.
Conditioning versus transforming
AgricultureID draws a hard line between two kinds of operation, because they behave differently and are described by different evidence.
- Post-harvest operations
- Condition a lot without changing what it is. Dried wheat grain is still wheat grain; cooled apples are still apples. The entity that went in is the entity that comes out.
- Processing methods
- Change identity. A commodity goes in and distinct products come out — each with its own uses, quality attributes, and trade.
Every method here names its input commodities and its output products explicitly, and the chain is checked: a product’s own source commodity must actually be an input to the method that claims to make it. A transformation is never inferred because two things share a crop.
One process, several outputs
Almost no agricultural process yields one thing. Crushing soybeans gives meal and oil, inseparably. Milling cane gives raw sugar, molasses, and bagasse. The distinction between primary product, co-product, and by-product is economic and technical, and it is applied per process rather than assumed.
Residual streams are modelled as by-products, not waste: most have established feed, fuel, fibre, or soil-amendment uses. Where a stream genuinely has no recovered use in a given context, that is stated with its context rather than generalised.
What these pages are not
This is an educational reference description of what the process does and why, not an operating instruction. Industrial processing requires qualified engineering, commissioned safety systems, and compliance with local regulation and the facility’s own procedures. No temperatures, pressures, concentrations, or settings here are intended as plant instructions.
Processing methods A–Z
Each entry covers the objective, the operating principle, the inputs and outputs, quality effects, loss points, equipment, environmental context, and safety limitations.
30 entries
- Processing method
Beet Diffusion Extraction
Sugar beet is not squeezed — it is washed out. Sliced beet meets water travelling the other way, and sugar diffuses out of the tissue into the water. What remains is beet pulp, a co-product the feed industry buys in its own right.
- Processing method
Centrifugation
Crystallisation makes sugar crystals but leaves them suspended in the liquid they grew from. Centrifugation is what actually divides the two — spinning the mother liquor away through a screen the crystals cannot pass, and separating raw sugar from molasses.
- Processing method
Citrus Juice Extraction
Citrus juice extraction recovers juice from the fruit’s internal segments while keeping the peel intact enough to stay out of the juice. It is as much an avoidance problem as a recovery one: the peel carries bitter compounds and oil that the juice must not inherit.
- Processing method
Cocoa Bean Cleaning and Winnowing
Cleaning removes the foreign material that travels with a cocoa lot; winnowing then cracks the bean and uses an air stream to carry the light shell away from the dense nib. It is the step that turns a bean into two entities — nib and shell — each with its own market.
- Processing method
Decortication
Decortication breaks the brittle woody core of a bast stem and beats it away from the flexible fibre bundles wrapped around it. It exploits a difference in mechanical behaviour — the core shatters, the fibre does not — and it produces two streams: fibre, and the woody shive.
- Processing method
Degumming
Degumming removes phospholipids from crude oil — a dissolved fraction that clarification cannot touch. It is the first refining step that addresses what is in the oil rather than what is merely floating in it, and is described here at concept level.
- Processing method
Evaporation and Crystallisation
Boiling water off clarified cane juice concentrates the sugar until it can no longer stay dissolved and crystallises out. This is where sugar stops being a solution and becomes a solid — and where molasses, the liquid that will not give up any more, is defined.
- Processing method
Flaking
Flaking presses steamed oat groats between smooth rolls into flat flakes. The rolls are the easy part — what makes rolled oats possible is the heat treatment beforehand, without which the product would go rancid.
- Processing method
Fruit Drying
Fruit drying removes water until the fruit becomes a different product with its own name, market, and shelf life. Drying grapes does not give dry grapes — it gives raisins, which is precisely why this is a transformation rather than a conditioning step.
- Processing method
Hammer Milling
Hammer milling pulverises grain by impact and holds it in the chamber until it passes a screen. It makes no attempt to separate the kernel’s fractions — everything that went in leaves together as meal, which is exactly what feed and many food uses want.
- Processing method
Juice Concentration
Juice concentration removes water from single-strength juice, leaving the sugars, acids, and solids behind. Removing water is not a side effect of the process — it is the entire point, because water is what makes juice expensive to move and quick to spoil.
- Processing method
Juice Extraction by Milling
Milling squeezes sugar-bearing juice out of prepared cane, separating the crop into a liquid carrying the sugar and a fibrous residue carrying the plant. That residue, bagasse, is what fuels the mill that produced it.
- Processing method
Juice Pressing
Juice pressing applies mechanical force to milled fruit to separate the liquid phase from the solids. It splits one commodity into two things with separate markets: juice, and the pressed solids known as pomace.
- Processing method
Maize Dry Milling
Maize dry milling separates the kernel into endosperm, germ, and bran before reducing anything. Taking the germ out whole is what makes the rest of the process possible — a crushed germ would put its oil through everything.
- Processing method
Malting
Malting persuades barley to begin germinating, then stops it. The grain is made to build the enzymes it would use to consume its own starch — and is dried before it can spend them.
- Processing method
Meal Desolventising and Toasting
Extracted solids are not meal yet. Desolventising removes the residual solvent that would otherwise make them unusable; toasting adjusts protein quality so that the meal feeds well. Two jobs, one operation, and neither is optional.
- Processing method
Mechanical Pressing
Mechanical pressing squeezes oil out of prepared oilseed by force alone, splitting one commodity into two co-products: oil and a protein-rich cake. It never recovers all the oil — the cake it leaves behind is why solvent extraction exists.
- Processing method
Nut Shelling
Nut shelling removes the hull and shell that protect a nut and recovers the kernel intact. It is a separation problem governed by a single tension: the force that breaks the shell is close to the force that breaks the kernel inside it.
- Processing method
Oil Clarification
Clarification removes the suspended solids that crude oil carries out of a press or extractor. It does not change what the oil is — it removes what should never have been in it, so that everything downstream works on oil rather than on a suspension.
- Processing method
Oilseed Dehulling
Dehulling separates the fibrous seed coat from the oil-bearing kernel before crushing. It carries almost no oil out with it, which is precisely the point: removing hull before extraction concentrates protein in the meal rather than diluting it with fibre.
- Processing method
Pearling
Pearling abrades barley’s hull and bran away layer by layer until a rounded kernel remains. Barley’s hull is fused to the grain and cannot be peeled off — so it has to be worn away, and there is no natural stopping point.
- Processing method
Rice Dehulling
Dehulling strips the inedible husk from paddy to yield brown rice. It is the first irreversible step in rice milling: paddy can be stored, but once the husk is off, the grain’s protective layer is gone for good.
- Processing method
Rice Grading and Brokens Separation
Grading sorts milled rice by kernel length, separating whole grain from brokens. It creates no breakage and repairs none — it decides which market each kernel already destined for a grade actually reaches.
- Processing method
Rice Whitening and Polishing
Whitening abrades the bran and germ off brown rice to produce milled rice; polishing burnishes what remains. It is the step that trades nutrition and shelf life against appearance, and the trade is deliberate.
- Processing method
Roller Milling
Roller milling separates the wheat kernel into its anatomical fractions and progressively reduces the endosperm to flour. It is a separation process before it is a grinding process — which is what distinguishes it from simply pulverising grain.
- Processing method
Semolina Production
Semolina milling breaks durum wheat into coarse endosperm particles and then purifies them. The mill’s object is to stop reduction while the endosperm is still granular — semolina is coarse endosperm, and turning it into flour would defeat the purpose.
- Processing method
Solvent Extraction
Solvent extraction dissolves oil out of prepared seed rather than squeezing it out, recovering the oil that pressure cannot reach. It exists because mechanical pressing is inherently incomplete — and it is described here at concept level only.
- Processing method
Stone Milling
Stone milling grinds the whole wheat kernel between two stones in a single action. Because bran, germ, and endosperm are crushed together rather than parted, what leaves the stones is wholemeal — one stream, not several.
- Processing method
Tomato Paste Production
Tomato paste production breaks tomatoes down, separates skins and seeds from the pulp, and evaporates water until a stable concentrate remains. It runs on processing tomatoes — a distinct commercial channel from the fresh-market fruit sold whole.
- Processing method
Vegetable Dehydration
Vegetable dehydration removes water from prepared vegetable tissue until it becomes a stable ingredient. Dehydrated onion is not a stored onion: it is a distinct ingredient product that rehydrates into food, and it is made from cultivars chosen for the purpose.
Sources
This article draws on the following authoritative sources. See our sources & methodology for how they are selected.
- [1]FAO — Food and Agriculture Organization (opens in a new tab)Authoritative
Food and Agriculture Organization of the United Nations (FAO)
Cited for: Agricultural processing and product definitions
- Type:
- Intergovernmental organization
- Jurisdiction:
- Global
- Accessed:
- 2026-07-12
- [2]USDA ARS — Agricultural Research Service (opens in a new tab)Authoritative
USDA Agricultural Research Service (ARS)
Cited for: Processing and product research
- Type:
- Government agency
- Jurisdiction:
- United States
- Accessed:
- 2026-07-12