Tobacco Growing In Victoria
Up to seven sales take place from May through to September, each sale being four days in duration. The week before each sale, tobacco is brought to the TCV selling floor in hessian bales. Bale presentation is a very important part of
marketing, bales weigh approximately 100-110kg. Each bale has a bar coded sticker attached to it, which has the growers identification number on it as well as the bale number of that particular bale.
On the day of each sale eight bales of tobacco at a time are loaded onto a conveyor belt. The bar code from each bale is scanned and the bales are weighed and assigned a lot number and randomly allocated to a buyer. Another sticker with all of this information on it is placed on the top of the bale. After each bale is weighed it travels along a conveyor to where a sample is pulled out and placed on top of the bale. The bale then moves into the selling room.
During the sale, two appraisers put a starter grade on each bale. The General Manager of the TCV and the various company buyers then view the bale and agree on a final grade. There were three major cigarette companies which buy tobacco in Australia: Rothmans; Philip Morris; and W.D. & H.O. Wills. These buyers purchased leaf from all plant positions, this is known as the 'run of crop'. After bales are bought they are assigned an internal factory grade by each company. As from September 1999 two companies exist, namely British American Tobacco Australia and Philip Morris Ltd.
The price of tobacco is based on a grade and price schedule which is negotiated with manufacturers at the start of each season. Each grade is defined according to the plant position, colour and quality. In 2001 there were 62 different prices and approximately 85 grades ranging from $7.35 to
$1.80 per kilogram of tobacco.
All of the details for each bale are then recorded on computer. The bales then travel down the conveyor where the samples are replaced and the bales resealed. The sticker with the lot number, grade, factory grade, weight, grower number and bale number is affixed to the bale for later identification. The bales are then placed in storage according to the purchasing company and the factory grade, before threshing or dispatch to manufacturers.
Threshing is the next stage of processing prior to cigarette manufacture. The function of the threshing plant is to separate tobacco lamina from its stem and to dry it to an even moisture content which provides optimum ageing conditions during storage.
Tobacco leaf is delivered from the sales centre in hessian bales. Processing begins with the selection of a particular grade blend. This leaf is taken out of storage and sent in batches to the threshing floor.
Each batch of bales is loaded onto 'carriages'. A carriage holding approximately 22 bales is moved into a vacuum chamber called the 'guardite', where a vacuum is drawn and the leaf is injected with steam and atomised hot water. This process makes the dry, brittle leaf soft and pliable. This reduces damage to leaf during threshing. Tobacco moisture content after this process is in the range of 14-17% with a temperature of 58-62C.
Blending, tipping and butting
The bales are placed on individual trolleys and presented to the 'blending line' where the leaf is manually placed on a conveyor belt. The leaf then proceeds to a cutting device which removes the tip and butt of the leaf. The tip contains minimal stem, while the butt is solely stem, so neither of these require threshing. The amount of tips/butts which is directly removed depends on the leaf position which being processed at the time.
The leaf with the tip and butt removed is transferred to a rotating cylinder for further conditioning. The tumbling action separates any hard packed pads of leaf whilst it is injected with steam and an atomised hot water spray. Moisture levels and temperature at this point are between 18-21% and 55-60C. The leaf is then transferred to a weigh band which ensures that a constant amount of leaf proceeds through the plant each hour.
Threshing is effected by mechanically hurling the leaf through a sharp toothed metal basket. As the leaf passes through the basket the teeth strip off the leaf blade from the stem. A carefully regulated draught of air then picks up the lighter pieces of stripped leaf leaving the heavier stems to fall away. This threshing action is repeated several times until the stems are stripped clean of all leaf. The leaf and stem then take separate routes, with the leaf being re-joined en-route by the tips that were previously removed at the blending/tipping line.
At this stage the moisture content of the leaf is quite high and inconsistent. Before the leaf can be packed, it is put through a steam heated drier that will dry it to a final moisture content of between 12-14%. At this moisture content the leaf can be stored for long periods without degrading.
After proceeding through threshing the stem is joined by the butts which were removed at the tipping line and dried to a moisture content of 10.5%. Before being packed the stem is mechanically brushed and vibrated across a perforated screen. This action causes any dust and fine particles to be sieved out, and also removes any small pieces of lamina still attached to the stem.
After the stem and leaf has been redried it is delivered by conveyors to the packing press, where it is packed separately into 200kg cases. Before the lid is put on these cases, each case is reweighed and all the relevant information such as grade, date, time, weight, and case number are recorded and printed onto tickets which are fixed on the cases. All cases are then moved to the packing storage area where they are despatched to manufacturers following cooling time and the next stage of cigarette manufacture.
Throughout each stage of the threshing process, samples are regularly taken and measured for moisture content, particle size, objectionable stem content, and leaf, stem and tip ratio.
Waste generated from threshing is approximately 1.5-2% of total tobacco leaf processed. It consists of collected dust, spoiled/mouldy and floor contaminated tobacco and wet tobacco as a result of equipment cleaning.
Further information on tobacco can be sourced from:
Please note: This publication is intended as general information only. The growing of tobacco in Australia is now regulated by the Australian Taxation Office (ATO). Permission for commercial or private cultivation or manufacture of tobacco should be sourced from Bob Harkins, Compliance Team Manager, (02) 9374 8501.
The advice provided is intended as a source of information only. The TCV and its officers do not guarantee that the advice is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence, which may arise from you relying on this advice.