Survey Of Damage To Potatoes In Shipping

Press, Volume XCVIII, Issue 28887, 6 May 1959, Page 17

Survey Of Damage To Potatoes In Shipping

Noting that there is a conflict of views between South Island shippers and North Island distributors on the question of damage to potatoes as a result of sea transport. Dr. I. D. Blair, head of the microbiology department at Canterbury Agricultural College, says in a college technical publication that measurable damage inevitably occurs within a system where perishable potatoes continue to be shipped in sacks and are subjected to excessive pressure. At present, however, he adds that there seems to be no alternative to this system.

Loading of filled sacks by hoist from the field on to motor transport generally involved lifting the sacks well clear of truck platform and then dropping them from a height of 12 to 18 inches, and often these sacks were bumped against the sides or dragged over the metal-lined edges of platforms. Where it was possible to examine the contents of sacks subjected to this treatment a high proportion of split or cracked potatoes occurred, particularly towards the bottom of the sacks. •

Where railway waggons were overloaded —loadings amounting to 140 to 150 sacks a waggon—severe crushing was caused, and this also led to handling problems at the ship’s side, for there appeared to be only one way for waterside workers to unload layers above waggon doors, and that was to drop these sacks off on to the wharf from this height. Under Railways Department control, Dr. Blair says, mixed cargoes are often assembled for shipment, and difficulties arose when potato cargoes, which should receive preferential treatment, were followed into the hold by case or metal cargo. Use As Stack

For storing in the hold the procedure was to make a stack beneath the hatch on which slings could be unloaded for wheeling or carrying cargo to distant parts of the hold. Watersiders looked for wheat, barley, or ground meal for these stacks, but if these were not available the only alternative was to use part of the potato consignment, with these sacks being severely crushed. Hooks were inevitably used in the handling of this cargo, and in at least one instance at Lyttelton sacks of potatoes received on an average eight blows each with loading hooks from the time railway trucks were unloaded until the potatoes were finally stowed in the hold. Presumably there was similar treatment at the port of unloading. It seemed to be agreed that vessels of small hold capacity I Kere preferable for potato cargoes. This was because small holds could generally be filled with potato cargo without the fcrtvessity to complete the filling

with goods of a kind harmful to the potatoes.

Dr. Blair also noted the poor quality of many sacks, which became severely torn during handling on the wharf or in the store. There also appeared to be good support for the contention that considerable pressure cracking resulted from the use of rope slings in hoisting sacks of potatoes in and out of holds, but in spite of this there was no inclination among those concerned to use wooden carrying trays on which sacks could be built up for hoisting. “In Wellington two separate inspections were made of South Island potatoes on the floors of the main produce firms,” said Dr. Blair. “On an average, secured by tipping out a selection of sacks and weighing cracked and severely damaged tubers, it was concluded that, at least among consignments examined. 10 per cent, was a fair figure to record for potatoes severely damaged by pressure cracking through the effects of transportation injury.”