Origin Fruit Group Grape Packing Protocol

PRODUCT & PREPARATION

Mould management

COOL CHAIN Table grapes need to be cooled as quickly as possible after harvest. One flow process must be used with a down ward trend of temperature, avoiding increasing the temperature at any stage. I.e. pick pack into final packaging, refrigerated then cold storage. Otherwise dehydration and mould development will occur. Product should be har vested and packed on the same day and not held over. Condensation at any stage must be avoided. The grape should be picked, packed within 6 hours of harvest. Packed boxes must be cooled to between 7/8 to 15/16 of the initial field heat. Modern forced air pre-coolers should achieve this within 6 to 10 hours.The grape should be further cooled to -0.5°C within a maximum of 48 hours after harvesting. Mature grape will not freeze at this temperature. The refrigerators should not set below -1°C, to avoid freezing occurring, notably on the pedicels. The pulp temperature must be measured from grape in the centre of the pallets as well as external temperatures, to ensure thorough cooling. The set temperature of the refrigerators must never be below -0.5°C, to avoid chill damage, especially to sensitive thin pedicels and laterals. The set temperatures and ambient air temperatures in all cooling rooms and pulp temperatures must be monitored and recorded and the instruments used must be checked and calibrated daily.

1. The grapes must be harvested in the cool of the morning, before the temperature exceeds +25°C. This is critical as later cooling with a high differential will lead to dehydration and deterioration. Avoid picking when there is high humidity that leads to condensation on berries. Free moisture encourages mould. 2. The grapes must be placed in a cooled environ ment in a maximum of 2 hours after harvest to be gin field heat removal, less than +25°C with high humidity, with a downward temperature trend. 3. The grapes should be processed in an air condi tioned / cooled packhouse. The packhouse tem perature should be cooler than the external tem perature, but not below the dew point, to avoid condensation. Typically the packhouse tempera ture would be +18 to 23°C. The relative humidity should be 85 to 95%, through fogging or wet wall coolers. 4. The packed grapes must be placed into rapid cool ing (forced air precooling) in a maximum of 4 hours from arriving in the packhouse (a maximum of 6 hours after harvest). 5. The rapid cooler (forced air precooler) must cool the grapes to between 7/8 and 15/16 of the field heat. The air delivery temperature of the rapid coolers must be managed to avoid condensation build up, noting that the relative humidity should be high at 90 to 95%.

6. After rapid cooling, the product should be trans ferred to a conventional coldstore and cooled to a uniform temperature of -0.5°C, in a maximum of 48 hours. The air delivery temperature of the refrig erators must not be set below -0.5°C. The Rela tive Humidity should be 90 to 95%. It is important that cooled product is not exposed to warm envi ronments as it will lead to condensation. Which increase the risk of mould development, splitting and sulphur damage. 7. The optimum pulp temperature of the Grapes must range from -0.5°C to +0.5°C when dis patched. 8. The ideal transport temperature is -0.5°C to +0.5°C. The lorry refrigerators must not be turned off at any point.

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Origin Fruit Group | Grape Packing Guide