Defect and tolerance
Sunburn on oranges, and the adjective that grades it
Sunburn destroys the oil glands of the outer rind on the face the fruit turned to the sun, and in stronger cases reaches the cells below. The citrus standard lists it in both graded classes, once as slight sunburn and once as sunburn, so a single adjective decides which class a lot belongs to.
The figures
| What it destroys | The oil glands of the flavedo, and in stronger cases the cells underneath |
|---|---|
| How it looks | From a light discolouring or yellowing through to patches of dead tissue |
| Where on the fruit | The exposed face, on fruit growing on the outside of the canopy |
| Class I wording | Slight defects in colouring, including slight sunburn |
| Class II wording | Defects in colouring, including sunburn |
| Extra class wording | Free from defects, with the exception of very slight superficial defects |
| Which family of defect | A colouring defect in the standard's own taxonomy, not a skin defect |
What it changes on an order
You bought Extra and the fruit is sunburned
Extra carries no clause for sunburn at all, so the route is the class tolerance rather than the class definition. That distinction changes which percentage in the table applies and how much fruit you can find before you have a case.
You grade on colour for a coloured-fruit market
The standard files sunburn with colour and not with scars, which puts it alongside the greening question rather than alongside rubbing. Specify it in the colour paragraph of your order and the packhouse reads you correctly.
You are buying fruit destined for juicing
The damage stops at the rind. Ask about juice content and the sugar to acid ratio, and decline to pay for an appearance nobody in your chain is ever going to look at.
What this note does not settle
- Nowhere does the standard attach a measurement to the word slight. Where two graders disagree, only a joint inspection resolves it.
- Sunburn taken on the tree and rind burn from heat in handling can look alike once fruit is in a box, and they are not the same defect.
- We hold no measured incidence and make no claim about how much sun exposure our plots carry.
Source: Commission Delegated Regulation (EU) 2023/2429, Annex I Part B Part 2 (specific marketing standard for citrus fruit), Ladaniya and others, Biotic and abiotic factors causing rind blemishes in citrus
Filed under colour, not under scarring
Where a defect sits in the taxonomy changes how you specify it. Sunburn appears in the colouring clause, in company with ordinary variation in how a fruit coloured up. It does not appear beside russets, silver scurfs or healed rubs, which live in a different bullet entirely. Buyers who write their requirements as one paragraph about blemishes are therefore missing the place where this one is actually decided.
Physically the damage runs deeper than a change of colour. The oil glands on the exposed face are destroyed, and where exposure was strong the cells beneath them go with them. A light yellowing and a patch of dead tissue are the same disorder at two distances along one scale, and the standard handles that whole range with a single adjective.
Paying for an appearance you have no use for
Fruit growing on the outside of the canopy takes the sun. That is also the fruit which sizes best and colours first, so a block cannot simply be steered away from the problem. What a supply chain can do instead is match the lot to the buyer, and sunburned fruit finds its price quickly in channels where a whole orange never reaches a customer's eye.
If you are buying for juice or for catering, say so in the first message. The conversation moves off appearance and onto juice content and the sugar to acid ratio, which are the properties you are actually paying for. Nobody in the chain benefits from selling you rind you will never look at.
Talk to the grower
Tell us the variety, the sizes and the delivery week you need. You get a delivered price and what we can commit to in writing, from the person who picks the fruit.
The grower handles enquiries. Response times are still to be confirmed.