CHILLED STORAGE OF BUTTER

Dominion, Volume 29, Issue 255, 24 July 1936, Page 7

CHILLED STORAGE OF BUTTER

Experimental Research EXPORT TRADE FOR TINNED LOTS A declaration that there did not seem to be insuperable difficulties in the way of developing an export trade in patted butter, while there was a possibility of exporting tinned butter in chilled storage, was made last night by Mr. C. R. Barmcoat, M.Sc., of the Dairy Research Institute, Palmerston North, when he discussed the results of experiments into butter storage and packing in a paper to the New Zealand Association of Refrigeration.

“The intelligent application of refrigeration processes to the storage of butter'must play an extremely important part in ensuring its arrival in a uniformly satisfactory condition on our overseas markets,” he said. He explained that for many years butter had been exported in the same holds as frozen meat, at a temperature of 14deg. F. This temperature had not been chosen because of its special suitability for the storage of butter, but rather because it happened to be a “working compromise” in temperatures suitable to the frozen meat trade. In a series of storage experiments only recently completed, samples of butter were kept for one, five and 16 days in a factory' cooler before placing them in frozen storage. After nearly eight months in cold storage, it was found that, in the case of sweet cream butter, the delay in the chiller had accounted for a loss of about half a grading point in the quality of the buttqr when finally examined. “It is considered that these conditions are not as poor as is sometimes the case in practice when the butter is railed or carted over long distances to x the freezing store, and under such conditions the deterioration, even over a shorter period of time, might be considerably' worse than in the example quoted,” he said. “The desirability of making the prefreezing period as short as possible is emphasised, and it would also be advantageous, it is considered, to employ ice-bunkered or refrigerated railway vans and lorries for the transport of butter over long distances, particularly during the hot weather

Export Trade in Patted Butter.

“There does not seem to be any insuperable difficulty’ in the way of developing an export trade in butter patted immediately after manufacture,” he said. “By using aluminium foil sandwiched between two thin layers of parchment (‘triple foil’) the extra cost, it is considered, would be not more than 40/- per ton of butter over and above the cost of packing it in 561 b. boxes in bulk form with parchment liners. The success of this trade would depend upon: Using only butter of the highest quality and keeping properties; ‘freezing down’ the butter as soon as possible after manufacture, storing it for not longer than about three months, and selling it as soon as possible after removal from cold storage; using larger wrappers than at present and packing the prints in special boxes, which would ensure a neat and compact pack. “Possibly a simple mechanical device could be employed for compressing the pats in the box before lidding. The box, when packed, would thereby be tightly filled, and the compressing effect, considered to be the main advantage obtained when butter is tinned under reduced air pressure, would thereby be reproduced. Chilling of Butter. Experiments to determine the possibility of chilling butter for export to the East in insulated vessels fitted with small refrigerators capable of maintaining only chilling temperatures had been made by the Dairy Research Institute. From these it could he concluded that there was a possibility of exporting tinned butter in chilled storage providing the period of storage was reasonably short (not exceeding about three months), and providing also that the discriminations m taste on the part of the buyers were not as critical as those of local or present overseas buyers. The chilling of butter tinned, m bulk (561 b. might be a better commercial practice than exporting patted butter in tins, from the following points of view :— (a) Reduction of surface area and defects to approximately one-fourth : and (b) reworking and patting the bulk butter at a factory situated near the place of sale would probably give a product of bettor flavour, and initially free from surface defects when presented for retail sate. Rapid Freezing. The rapid freezing of butter at verylow temperatures had been tested. Witli a high-acid type of butter, the experiment was unsuccessful, but in the United states and Canada, butter of the highly flavoured (“Danish”) type was kept for many months at Iwo temperatures from —5 to —2O deg. F. without excessive deterioration, suggesting that ti would be possible, with experience, to manufacture and store this type of butter in New Zealand. With sweet cream butters the experiment was quite successful. The buttersalted and unsalted—when placed on the day after manufacture in cold storage at 14 deg. F. lost two to two points and a half, while other samples of this butter placed at the same time un storage at —5 deg. F. had lost only one point and a half, <m examination when about eight months old. When tlie freezing was delayed for 10 days (during which the butter was kept in a chiller at about 40 deg. F.), the samples stored at 14 deg. F. had lost two points and a half, those at — 5 deg. F. two points. Butter (even the unsalted variety), when frozen soon after manufacture and kept for seven months and a half at —5 deg. r -. bad lost only about one point and a halt in grade, ns against two points and a halt for the butter treated in the normal manner. “This seems to be a fairly good indication of the advantages to be expected from the ‘rapid freezing’ of butter, he said. .