Tendertips
Background
Chutes where spears leave the line
Spears tipping into chutes from the moving line
The project team in the laboratory (from left Ken Mercer, Margo Shaw, Ralph Ball and Colin Plaw)
Model of the line used to 'singularise' the asparagus before it passes under the camera (click to enlarge)
New Zealand products, especially fruit, flowers and vegetables, find a ready market in Japan, where their quality is recognized, and good prices are paid. However, to compete in this market, your products have to approach perfection. This is especially true of a speciality product like asparagus, which is regarded as a bit special, even in New Zealand where it is plentiful.
It has taken many years to develop Tendertips product to its present level of quality, and acceptability to all levels of the Japanese marketing and distribution chain, from the importer to the consumer. The process of growing, harvesting, transporting, storing, grading and packing asparagus is labour intensive at every stage. Being a natural product, every stage is difficult to mechanize, let alone automate, and the delicate nature of the asparagus ‘spears’ prevents “brute force” solutions which might work with less delicate products, such as potatoes or swedes.
All these factors have resulted in the traditional asparagus pack-house operation having a very high labour content, leading to difficulties recruiting suitably skilled staff in sufficient numbers to cope with the product flow at the peak of the harvesting season.
This situation, though less than ideal, was workable as long as the overseas market was steady, and customer was prepared to pay premium prices.
Nevertheless, the opportunity to make bigger margins and increase throughput rates, by automating selected stages of the manufacturing process (Conceptual statement), was recognized about 10 years ago, and resulted in a machine which could grade and sort the spears by size, and collect them into bundles of specified weight, the final stages of packing and presentation being left to skilled staff.This machine was well received in New Zealand, with all but a few small packhouses investing in the new technology. As a result, pack-out rates increased substantially and labour costs were reduced. However, the quality of the finished product was not as high as in pure manual systems. In particular, the control of bundle weights, and the control of the weight of individual spears within the bundle, left a lot to be desired. In the last ten years there has been enormous progress in computers, and in the control systems which they drive, and it was decided that a fresh look at the problem could yield benefits: lower costs, better quality, higher production rates.
