Checking grapes and blueberries on arrival
A container is accepted or claimed on what the first hour of inspection finds. Here is how the standards say to sample, what to count, and how much is allowed.
Take the pulp temperature first, then sample at random across the lot, open the punnets, and count defects by type. Compare each count with the tolerance for the class in the contract. For Class I grapes that is 10% of bunches below class, of which at most 1% decayed. For Class I blueberries it is 10% below class, of which at most 2% decayed or below the minimum requirements.
Start with temperature
Read the pulp temperature before anything else, on fruit from the door end and the deep end of the container. Table grapes should be held with the pulp at −0.5 to 0 °C, and South Africa’s export rules hold grapes at a pulp temperature of −0.5 °C. Blueberries belong at −0.5 to 0 °C. A warm reading changes how you read everything else: decay that is slight at arrival will grow on a warm shelf.
How many boxes to open
The OECD rules for conformity checks set the minimum sample needed to declare that a lot does not conform:
| Packages in the lot | Packages to sample |
|---|---|
| Up to 100 | 5 |
| 101–300 | 7 |
| 301–500 | 9 |
| 501–1,000 | 10 |
| Over 1,000 | At least 15 |
From each package, take 15 units but at least 3 kg. Punnets and other sales packages of 3 kg or less must be opened and the fruit taken out before it is checked. Peru’s grape standard uses a different rule, the cube root of the number of boxes, drawn at random from 20% of the pallets. Whichever method you use, write it in the report.
Table grapes: what to count
- Decay. Soft rot from fungi or bacteria, above all grey mould (Botrytis), which develops even at −0.5 °C and spreads from berry to berry. It is the most destructive postharvest disease of table grapes.
- Shatter. Berries that have fallen off the bunch. It rises with maturity, is worse in seedless varieties and mostly comes from rough handling at packing.
- Stems. Stems that are brown, dry and brittle point to water loss after harvest.
- SO2 damage. Bleached, sunken or discoloured areas from sulphur pads, counted in US grading as “sulphur burn”.
- Split, crushed, wet or shrivelled berries, and weak, translucent “waterberries”.
- Colour and size. Red and black grapes against the colour required by the class, and bunch weight against the minimum (75 g for Extra and Class I in the EU standard).
- Sugar. °Brix, and the sugar:acid ratio where the contract uses one, on the least ripe bunches. How sweetness is specified.
Table grapes: how much is allowed
| Standard | Tolerance |
|---|---|
| EU, Extra Class | 5% of bunches by weight may meet only Class I, at most 0.5% Class II |
| EU, Class I | 10% may meet only Class II, of which at most 1% below Class II or decayed; plus up to 10% loose berries |
| EU, Class II | 10% may meet neither class nor the minimum requirements, of which at most 2% decayed; plus up to 10% loose berries |
| US, at destination | 12% defects in total, of which 8% permanent defects, 4% serious damage and 1% decay; 10% for colour |
Regulation 543/2011 was replaced by Regulation (EU) 2023/2429 from 1 January 2025. The Brix and 75 g bunch minimums are unchanged, but the 75 g minimum now applies to Extra and Class I only. The tolerances above are from the 543/2011 text.
Blueberries: what to count
- Decay and mould: grey mould, ripe rot, and Rhizopus above 10 °C.
- Soft, leaking or split berries, and overripe fruit whose flesh is soft and mushy.
- Shrivel from water loss.
- Bloom. Extra Class and Class I berries must be practically covered with bloom.
- Clusters of berries stuck together, attached stems, and red or green berries: fruit must be fully blue, with little or no red at the stem end.
- Firmness, if the contract sets it. There is no standard method; compression testers are most common.
Blueberries: how much is allowed
| Standard | Tolerance |
|---|---|
| UNECE FFV-57, Extra Class | 5% may meet only Class I, at most 0.5% Class II |
| UNECE FFV-57, Class I | 10% may meet only Class II, of which at most 2% below minimum requirements or decayed |
| UNECE FFV-57, Class II | 10%, of which at most 4% decayed |
| US No. 1, at destination | 10% attached stems, plus 12% other defects, of which 2% mould or decay |
What the report should contain
- Container, lot and package identification, and the arrival date and time.
- Pulp temperatures and where they were taken.
- The sampling method and how many packages and units were inspected.
- Brix (and acidity and ratio where the contract uses them), measured on the least ripe fruit.
- Colour, bunch weight and berry size for grapes; size or count for blueberries.
- Defects counted by category (permanent defects, serious damage, decay), each compared with the class tolerance.
- Photographs of the packages, the fruit and the temperature readings.
- OECD, Scheme for the Application of International Standards for Fruit and Vegetables (OECD/LEGAL/0346), 2006.
- EU Regulation 543/2011, table grapes, UK Government copy.
- USDA AMS, US Standards for Grades of Table Grapes, 1999; US Standards for Grades of Blueberries, 1995.
- OECD, Berry Fruits (UNECE FFV-57), 2024.
- Peru, INDECOPI NTP 011.012, 2005.
- USDA, Agriculture Handbook 66, grape and blueberry chapters, 2016; Chaves Junior et al., SO2 pads and liners on table grapes, Pathogens, 2019.
- South Africa, Regulations relating to the Export of Perishable Products, 2025, section 51 (table grapes); Rivera et al., blueberry firmness, Postharvest Biology and Technology, 2022.