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Issue 4, Oct-Nov 1997

 

HARVESTING AND POST HARVEST

No. 2 in the series by Bradley Field, Bush Tucker Supply Australia Pty Ltd.

In Issue 3, we looked at Farming, Harvesting, Timing, Cleaning, Packing and Storage. In this second installment, we take the produce to market...

Transport

This is largely out of both our controls so the best solution is to take out the higher risk areas of timing, destination and temperature. Where possible, ship goods with an expected delivery to Sydney of Monday to Thursday to avoid the risk of goods being lost in a depot somewhere on Friday and thawing or composting over the weekend until pick up can be arranged. Mark all boxes clearly with a destination and phone number, sender's name and phone number, storage temperature and sequentially number boxes. Let us know when you intend sending your shipment and advise us of the consignment note number and expected delivery date.

Remember to send paperwork attached to the goods so we know who sent them (including address and phone number) and the shipment weight so we can arrange payment.

Receipt into BTSAust. store

We either receive the goods direct into store or in a lot of cases we collect them from BGF at the Sydney Fruit Market which is a 40 minute round trip, has no refrigeration and no access after 12.00 midday. We therefore need notification so that stocks do not deteriorate at the market.

When we receive the goods they are immediately inspected and weighed. We check this off against your invoice and the invoice is then passed on to our accounts person for processing. We pay our bills promptly on 30 days from end of month or sooner if we can, but this all relies on complete paperwork being included.

Our R&D then continues with respiration rates, specialist packaging, flavour extractions, microbiology analysis, flavour extensions, quality control improvements etc.

As we start to apply quality assurance guidelines, you as a grower will also need to start to supply more specific information eg. batch numbers and stock segregation, stock temperatures on departure, organic certification etc.

It would be worth you starting to compile accurate information now on your stock source, growing conditions, crop management techniques, harvest strategies, weather conditions, yields etc. This not only provides statistical information in the event of having to solve a problem but should also be an asset should you ever want to sell your business.

There are many dedicated growers committed to quality and improvement. This attitude is a necessary ingredient for future product and industry development.

Picking Process for FRUIT

Type of trees to pick from: Healthy, mature, clean trees away from vehicle exhaust, industrial fallout and agricultural overspray.

How to pick

Place a clean tarp under the tree. Depending upon the height/position of the tree, use either a clean ladder, cherry picker, scaffolding, vehicle or other platform.

Always use clean hands and or gloves (we suggest you carry clean water in your vehicle.)

Most fruits are picked once fully ripe. However pick only clean, best quality fruit and allow the fruit to drop onto the clean tarp. Once the tree is picked, gently pour the fruit into clean boxes/containers ready for sorting. Do not overfill boxes as ripe fruit may be squashed. Caution: many bush fruit trees have brittle branches and should not be climbed for safety reasons and to avoid damage to the trees. Minimal handling of fruits also helps maintain fruit quality.

Sorting

Clean,. best: quality fruit is preferred at peak ripeness and free of grubs, insects, drt etc. Sort the fruit from any leaves, small twigs or any foreign matter. If uncertain as to the ripeness please contact BTSAust. for clarification.

Bagging

BTSAust supplies food grade zip-lock bags for fruit to be bagged in minimum 1 kg weights. Please call BTSAust for supply of these bags.

Storage

Fruits must be kept frozen (-18 degrees C) prior to shipment. Immediately after picking and sorting place bagged fruit in a freezer for quick freezing. Once frozen solid (12-24 hours) the fruit can be packed in eskies for transport.

Tansport

Mark the outer iabel of the esky. We recommend that you call BTSAust. for the best means of transport for your consignment

Payment

Please discuss payment terms and conditions with BTSAust. It is imperative that an invoice or delivery docket accompany all shipments to advise our accounts department that payment is due. Issue 5 will have examples of invoice/delivery dockets.

Picking Process for LEAVES

Type of trees to pick from: Healthy, mature, clean trees away from vehicle exhaust, industrial fallout and agricultural overspray.

How to pick

Place a clean tarp under the tree. Depending upon the height/position of the tree, use either a clean ladder, cherry picker, scaffolding, vehicle or other platform. Always use clean hands and or gloves (we suggest you carry clean water in your vehicle.) Leaves should be picked from the stem and packed in polyboxes with a butcher paper lining. Refrigerate leaves or store in a cool place prior to transit. Do not overfill polyboxes to ensure the leaves to do not ferment or are stressed unnecessarily. (We recommend a maximum of approximately 3.5kg per standard broccoli box.)

Caution: Many trees have brittle branches and should not be climbed for safety reasons and to avoid damage to the trees.

Sorting

Clean, mature, best quality leaves are preferred being free of grubs, insects, dirt etc. Sort the leaves from small twigs or an}1 foreign matter. For information on best post-harvest techniques please call BTSAust.

Hygiene

Please maintain strict saniurv and personal hygiene standards when picking and packing leaves. Minimal handling of leaves maintains sanitarv standards and the quality of the produce. Please be aware that domestic animals can also contaminate produce which BTSAust. cannot accept.

Storage

Leaves must be kept cool (+ 2oC) prior to shipment. Immediately after picking and sorting, place leaves into a refrigerator for quick cooling. Once cool the leaves can be shipped for transport.

Transport

Mark the outer label of the esky. We recommend that you call BTSAust. for advice on the best means of transport for your consignment.

Payment

Please discuss payment terms and conditions with BTSAust. It is imperative that an invoice or delivery docket accompany all shipments to advise our accounts department that payment is due.

Suggestions on Hygienic handling of Bush Food fruits and herbs

Some human and animal bacteria are potentially hazardous to humans as we have seen with the recent Garabaldi Meats and Peanut Butter scares. E-coli bacteria is one of the main concerns and each bacteria can multiply 500 fold every 3 hours. E-coli is present on your skin, when sneezing and in higher more damaging numbers from faeces of humans and animals. Salmonella also multiplies at much the same rate.

Basic steps to reduce the risks of contamination are:

  • Cleanliness
  • Maintain clean handling procedures from growing to transporting:
  • use disposable gloves or regularly sterilised gloves for all handling
  • do not sneeze near or over the foods
  • always make sure hands are washed before handling any product, particular!) after a trip to the bathroom
  • keep work boots clean as they can be a source of contamination if you walk on manure and then onto a collection tarp or floor in a cleaning area - if in doubt, clean the surfaces you collect and clean on must be free from contamination (use residue free disinfectants like chlorine or dilute methylated spirits at 70% into water)
  • tarps and preparation floors must be regularly cleaned particularly if you have dogs or cats
  • eskies or boxes you use are also a possible source of contamination from animal urine or human sneezing. Store containers away from potential problem sources, if in doubt clean them or use plastic inners for cardboard boxes

Education

Make sure all handlers are aware of the health risks and that they abide by the ideas above.

Place signs up to remind staff and visitors to maintain the standards

Keep abreast of changes and the ingredients in fertilisers eg. some chicken manure products contain e-coli and sometimes salmonella which can be spread by wind or poor handling onto leaves.

Some TAFE courses offer basic courses for continuing education

Monitoring

Periodically check your site, equipment, handling methods and staff to keep the hygiene issue top of mind and effective

Maintain records of your shipments for future batch control standards.

Next issue -the paperwork.

The Southern Bushfood Association

Articles in the Australian Bushfoods Magazine have had a strong northern NSW and Queensland orientation to date. However, readers should be aware that there is considerable interest in bushfoods in Victoria, SA and Tasmania and a very strong association - Southern Bushfood Association (SBA) - of over 130 members, comprising growers, value adders, industry teachers and marketing and other food industry professionals.

The SBA is working with growers to develop a strong industry and tackling the following issues:

• The move away from wild harvesting towards plantation production (often in polycultural settings) to ensure best quality products, secure supply and make use of the best varieties and cultivars.

• A reasonable pricing structure which does not inflate prices and yet offers a reasonable return to growers.

• Development of strong links to Aboriginal groups with interests in the industry.

• Development of sound agronomic and other plant data for new growers looking to develop plants which are appropriate for their area. Southern plants are generally quite different from those portrayed in the Magazine.

• Development of quality production processes through safe, clean, consistent and sustainable production,

• Development of systems of support and promotion for all products of members - be they food production, education, training, value adding, tourism related and so on.

The SBA has established strong connections with training and research institutions and is establishing a training and research program with:

• The Victorian University Of Technology (Food Industry Departments)

• Melbourne University - Burnley Campus (Vic College of Agriculture and Horticulture)

• William Angliss Institute of TAFE.

The Association is working with the William Angliss Institute on a joint research submission to RIRDC to investigate southern markets for bushfood products. We are also in line for a National Heritage Trust grant to investigate plants with bushfood and other economic importance which have potential for use in saline affected soils in the north central regions of Victoria.

The SBA is linked to both ANB1C and CORBO (the newly formed Committee of Bushfood Organisations - see issue No 3) and sees both bodies as complementary and able to co-operate in the furtherance of the industry.

There need be no fragmentation and indeed the SBA is determined to maintain full links to all sectors and a co-operative and co-ordinating role for all elements of the industry in southern states. Associations such as ours are interconnected and share information via newsletters, exchange of technical information and some products.

We would be pleased to provide any further information readers may require. In further issues we may be able to elaborate more on some of the southern bushfood products and activities of our members and association.

Gil Freeman, President Southern Bushfood Association C/- 21 Smith Street Thombury 3071 Ph/Fax (03) 9416 7150 Email gil - AT - compost.apana.org.au

Acacia ~ research, field trials and databases

Brian King, Muntari Wild Foods

Belonging to the Family MIMOSACEAE, the Genus Acacia or 'wattle' as it is commonly known comprises somewhere in the order of 650- 700 different species, most endemic to Australia. Distribution is widespread through many plant communities, from coastal sands behind beaches can be found Acacia sophorae and in Eucalypt forests where it forms part of the understorey growth eg Acacia pycnantha, through to arid inland plains and low woodland communities where it can sometimes be the predominant shrub, eg; Acacia anuera (Mulga). Many species are fast growing small to medium shrubs up to 4m in height, however, there are a number of larger trees, including one that can grow to a height of 20m or more (A.silvestris or Red wattle).

acaciaCharacteristic features of this group are the golden, yellow or cream ball or rod shaped flowers, usually occurring in clusters. Flowering times vary from species to species but a large portion tend to flower through winter and early spring, however it is always possible to see some in flower throughout the year. The genus can be divided into two major groups, those that have phyllodes or modified stems like A. anuera (Mulga) or A. acinacea (Gold Dust wattle) and those that have fern-like or bipinnate leaves as in A. meamsii (Black wattle) and A. bailevana (Cootamundra wattle).

There is an amazing variety of phyllode shapes and sizes which can be anything from long and strap-like (linear) as in A. stenophylla (River cooba), broad and sickle shaped as in A. pycnantha (Golden wattle) or thorn-like (narrow) as in A. rupicola (Rock wattle).

It is thought that the phyllode evolved as a way for the plant to conserve moisture in hot dry climates. Perhap by having long and narrow phyllodes - or the phyllodes angled away from the horizontal, there was less exposure to direct sunlight which reduces loss or moisture due to evaporation.

Pod and seed size vary between species. The pods maybe restricted between each seed as in A. stenophylla or oblong and almost flat as in A. notabilis. Seed for many Acacias ripens through the summer months when the pod begins to turn brown and dry. The seeds of most species are not usually held in the pods for very long, a matter of weeks, sometimes less and this can vary depending on seasonal conditions. The pods when dry, split open and wind, parrots and gravity help dislodge the seeds. Ants are also known to remove seeds but it is usually for the protein rich aril and not the seed itself, which is discarded.

Bushfood species

The Acacias of particular interest to us are those that produce edible seed. Of the large number of species found in Australia only a small number are known to be safe for human consumption and of these, perhaps even fewer could currently be classified as useful to the bushfood industry, although this may change as research continues into this interesting group of plants.

Table (1) lists a number of Acacia species which produce edible seed. Of the listed wattles, it remains to be seen how many species will be commercially viable in plantation situations, which I suggest is the only way the industry will be able to supply predicted markets while still maintaining consistent quality/quantity. Also, given that there are a number of unknowns involved in the cultivation/maintenance/harvesting of the species, it may be a number of years before enough data is disseminated and experience/confidence gained by industry participants to enable truly sustainable farming of Acacia crops that can also meet market requirements.

MWFPA Field Trials

When first researching the possibilities of plantation grown bushfoods, some 10 years ago, it was recognized that a large commitment to trialing both plants and production methods would be required if we were going to be successful as there was little information available on bushfood farming at that time. Since establishing Muntari Wild Food Plants three years ago we have made that commitment and are at present conducting field trials on a number of different species. There are a total of 32,000 plants involved in three separate stages of development.The main aims are to establish:

  • a selection of suitable genotypes from different species and provenance's
  • water and nutrient regimes
  • crop maintenance routines
  • polyculture techniques
  • Large scale harvesting/storage production methods
  • long term crop viability

The Starting Point

Of the species selected for the trial, we have collected seed from as many different provenances for each species as was practical. We did not collect as much as we had first hoped -in some areas pests, stock grazing, bushfires and land clearing restricted collection of good quality seed. In future it is hoped most of the uncollected sites can regenerate to a point where some seed can be collected and used in our research. Although seed was only collected from healthy specimens, no attempt was made to collect from any specific form, on the contrary, we were looking to include as much diversity as possible. This has given a reasonable selection of genotypes from which to work. All specimens were labeled for future reference and a percentage of each set aside for content analysis (vitamin, mineral, protein, toxin).

The required number of seedlings are propagated in the nursery and planted out into prepared one hectare trial plots located in different areas across South Australia which provide good diversity of rainlall and soil types. Rainfall areas range from less than 250 to more than 650mm per year and soil pH ranges from 4.5 (very acidic) to 8.5 (alkaline). Soils structures range from sandy to heavy clay-loams. Planting out started during late Autumn 1996. Each trial plot on completion, will contain a minimum number of each of the species but vary on row spacing and the distance between each plant. A number of plots will contain all Acacias, while the remainder will have different bush food species dispersed throughout. This has the benefits of allowing data collection on other plants of interest while at the same time assessing the viability of polyculture versus monoculture type systems.

Each site has a number of trials running concurrently to obtain as much information as possible on irrigation regimes, fertilizer application rates, pruning and pest control methods, etc. From these trials, plant maintenance programs can be developed and suitable genotypes selected and used for future plantations. The produce collected from all trial plots will be used in a range of value added products, the sale of which helps fund our ongoing research. It is hoped plantation grown produce will eventually replace what we currently buy in from wild harvest sources.

A Little Assistance

As the trials and maintenance projects accumulate vast amounts of information which must be recorded and retrieved easily, we have installed a computer system with custom database software which allows us to store many different types of information, including images. Such information can be any thing from growth rate of individual plants, when it was last pruned or watered, fertilizer application rales and times, etc. This data can then be used in graphs and tables to show such things as real plant growth versus amount of water or fertilizer applied or what the average rate of growth was since the last pruning, etc. Trends in plant performance can then be identified with minimal effort. It certainly helps to have a little assistance at times! Of course, the result from the software is only as good as the data entered into it and that's where all the repetitive work and accuracy is required, gathering the information. Again, to streamline costs and time, we have chosen to use small handheld computers with specific software which allows each site to enter the required information. Each site also has a compact monitoring station which is capable of logging weather, soil moisture and other site information. Samples are automatically recorded by each station once an hour, however, some data is recorded every 6 minutes. The information from this station can be downloaded to the handheld computer periodically (usually once a week) where it is then only a matter of connecting to a phone to zap the data up to our main computer, or alternately, the unit can be brought in to download its information into the main computer's database. While it all sounds a bit high tech and expensive, it is surprising how cost effective this type of system really is. Resources are actually saved using this method, resources that can be used productively elsewhere, like feeding, fencing, weeding, watering, pruning, planting.

Harvesting & storage

One of the problems faced in harvesting the seed of Acacia is the uneven ripening of the fruit, which is often over a few days or weeks. If one were to wait for all pods to ripen before picking, around 8-10 7r loss of seed must be accepted. This percentage would have fallen to the ground, be destroyed by weevils or be taken by birds, (personally noted). It is possible to reduce the losses but the costs involved when dealing with large plantations may be prohibitive. Our trials include methods to reduce these losses economically.

When harvesting from a small number of Acacias, hand picking would perhaps be the most efficient way but on a large scale this is not practical. In the last two years we have placed a great deal of effort into different methods of mechanically harvesting wattleseed. Some prototypes have been complete failures, others look very promising but all still need refining to minimise post harvest cleaning and handling.

Storage

Before seed is stored it must be clean, dry and free of insects. It must be stored in a cool, dry, dark place where it may be kept for long periods, reportedly years. We are still testing the storage life of raw Acacia seed (as food) so we do not have the answer for that just yet but it's coming. A number of small scale storage bins are being trialed. Each one is capable of holding 500kg of wattleseed and can be sealed airtight if required.

Propagation

Propagation of Acacia seed requires some pre-germination treatment to hasten or improve germination. Three ways are shown below, none are difficult and all can be useful.

Hand scarification involves scraping away a small section of the outer seed coat with a sharp blade or by rubbing with fine grade sandpaper to thin a section of the seed coat. Both of these methods are time consuming but occasionally useful when dealing with a small number of large seeds. Using a gemstone tumbler with coarse damp river sand. Seed is placed in the tumbler with a volume ratio of sand to seed approximately 10:1 respectively. The tumbler is left running for between 3-12 hrs depending on the thickness of seed coating and size of seed. This method relies on the abrasive tumbling action of sand against the seed to wear down and hence soften the outer seed coating. It is very useful for seeds that would otherwise be too small to apply the hand method and/or for seed that can have the embryo destroyed by the hot water method. Hot water treatment. The easiest method for the majority of Acacia seed. Is used to soften the outer seed coating with hot but not boiling water.

Put the seeds to be treated into a container. Boil some water, remove from heat and let cool for 2-3 minutes. This is sufficient to lower the temperature to around 70-80" C in that time.

Exact temperature is not critical, just not boiling! Next pour the water over seeds and allow to stand at least overnight.Any seed that has floated to the surface after this time can be considered useless and removed.

We have found that germination reliability can be increased by leaving the seeds immersed in this water for up to a maximum of 3 days depending on the species. By this time most will have become swollen. As could be expected, those with soft outer seed coats require much less time than those that are harder.

Experiment to get best results. The seeds may then be placed into a growing medium for germination (7-10 days average).

Table 1

Botanical Name - Common Name - Size(m) - Distrib - Seed Size

Acacia aneura Mulga 5-8 Arid Med

Acacia argyophylla Silver mulga 2-3 Semi-arid Lge

Acacia coriaciae Dogwood 3-5 Arid Lge

Acacia kempeana Witchety bush 2-4 Arid Sm

Acacia murrayana Colony wattle 2-3 Semi-arid Med

Acacia notabilis Notable wattle 2-3 W/spread Med

Acacia pycnantha Golden wattle 3-4 W/spread Sm

Acacia retinodes Wirilda 3-4 W/spread Sm

Acacia sophorae Coastal wattle 4-5 Coastal Sm

Acacia stenophylla River cooba 4-7 Semi-arid Lge

Acacia tetragonophyla Curara 2-5 Arid Sm

Acacia victoriae Elegant wattle 2-3 W/spread Med

The plant and seed size table has been formulated by personal observation from more than 200 locations over a 5 year period. The data has been averaged and therefore some individual sites may produce marked variances from that average.

Kangaroo Meat

A great product getting even better

Kangaroo meat has been around a long time, it's been a highly thought of gourmet meat for human consumption for at least 100,000 years (there is no doubt that kangaroo was a fairly rare and very prized treat in Aboriginal diets).

Only recently has white Australia started to recognise this remarkable meat for what it is, a wonderfully tasty, tender and healthy product.

The good news is that recent developments mean kangaroo is getting even better

Over the last two years new standards of meat hygiene control for kangaroo meat production have been developed in a joint industry/ government initiative under the auspices of the ARMCANZ Meat Standards Committee.

These lay down detailed and strict controls for every step of kangaroo production, from the initial harvest process right through to packaging and labelling. And thankfully they are uniform throughout Australia, so kangaroo produced in any State can now be freely traded throughout the country.

All human-consumption kangaroo producers now must abide by these standards.

The ARMCANZ standards require (for example) detailed monitoring of meat contact surfaces for micro-biological contamination, they require similar monitoring of finished product for contamination and quality faults, all animals must be inspected by suitably qualified inspectors and strict inspection regimes must be complied with.

On the harvest side all kangaroo harvesters must be assessed and accredited by the relevant state Meat Hygiene Authority to ensure they are both trained and competent in the meat hygiene aspects of their job. They are also required to pass marksmanship assessment. So all professional harvesters are now guaranteed to be fully competent at their job. In addition, their harvesting vehicle and equipment is assessed to ensure it complies with meat hygiene requirements and most have gone through significant upgrades to achieve this.

All of this serves to enhance the qualities of what is already a naturally healthy meat. Kangaroo can claim to be a uniquely healthy meat both in terms of its disease free status and its healthy dietary status.

Disease rates for kangaroos are much less than those of domestic livestock. This makes good common sense when you think about it- if a wild animal gets sick it generally dies, if a domestic animal gets sick we treat it and hence foster the retention of diseases in the population.

Some of the facts - rates of toxoplasmosis infection in kangaroo and wallaby are less than 4%, toxo infection levels in lambs are typically over 15% and in older sheep over 60%. Similarly rejection rates for disease conditions at post mortem inspection in kangaroo have been shown to be only 0.7%. compared to typical rejections rates of over 2% for domestic animals.

Kangaroo can also be a valuable contributor to a healthy diet. We all know it has very little fat (less than 2% I - red meat doesn't come any lower than this. The recent good news is that a large proportion of the fats present are polyun-saturated and that these actually help clear blood vessels of blockages and restrictions. So kangaroo can activeK help prevent strokes. It's also very high in protein and iron, particularly importantly for females

So the net picture is that if you really enjoy eating meat, kangaroo is the meat you can eat as much of as you like. It's a great product that's getting even better.

From the Editor

Choosing Acacia Species for Bushtucker

Harvest and Post Harvest

A walk In the Park

The Southern Bushfoods Association

Acacia ~ research, field trials and databases

Kangaroo Meat

Extracts from 'The Bushfoods Handbook' - Vic Cherikoff

Bush Foods in History Series 3 - honey from native bees

Notes: Acacia - John Mason

Wattles and Marathons

Tucker & Timber: Integrating Bushfoods

Bush food plants of western Queensland

Bunyas and the whole farm plan - John King

Products & People: Basically Wild Edible Art

Protecting New Bushfood Varieties

Profile: Oliver Carter: Mr Lilly Pilly

Book Reviews

DOOR Marketing

Tasting Australia

News

Resources

Groups

Recipes

Indigenious Roasts

From the Bookshop

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