A new trucking method of liquids, called the Softtank system, has recently been developed and given attentions to improve conventional trucking method. The system is equipped with a size-free flexible bag with a pressure-resistant watertight zipper. It could be instaued on common trucks with metal frames to prevent agitation of the liquid. Unique characteristics of this system are as follows:1) Load volume of liquid is free.2) Consolidated service is available.3) The
system can be folded into smaller size, so that other goods can be loaded on the return trip.4) Attached zipper makes
cleaning of the inside of the bags easy and the sanitation task become independent from the drivers' responsibility.5) It is recyclable for several hulldred times.
By using raw cow milks, the Softtank system was compared with a conventional trucking method on the quality control including sanitation, temperature, and bacteria counts. In the summer of 2001, test trials were performed five times. The average of the transportation distance and duration were about 600 km and 19 hours, and provided the following results:
1) Just before loading the milk, the cleanness of the containers was tested with a commercial ATP detection kit. The Softtank containers were sufficiently clean at each trial, but the test detected microorganisms of contamination in some parts of the container of the tanktrucks. The contamination diminished by the fifth trial. The cause of the contamination of the tanktruck appeared to be a lack of explicit sanitation specifications to the sanitation operators.
2)Increased temperature of the milk during trucking was observed at the upper part of the container of tanktrucks.Since the increase was not depended on the outdoor temperature, it might be caused by the increased temperature of head space(upper part) of container, which is caused by the direct rays of the sun.
3) No increase of microorganisms was found throughout the trucking trials.
4) Fat content of the milk transported by the tanktrucks was increased about 0.1%. This was thought that some of fat
globules were disrupted by churning and large sized fat globules (cream)were produced during the trucking by the
tanktrucks. This phenomenon was not observed in the Softtank system.
These results indicate that the Softtank system is a superior trucking method to achieve better sanitation of the containers and maintain higher quality of raw cow milk.
生乳輸送における衛生管理と品質変化-タンクローリーとソフトタンクシステムとの比較検討-
ms-v52n3ｐ127-136.pdf
(785.5KB)
