Culinary bamboo shoots

Overview

Bamboo is found in a variety of climates, ranging from hot tropics to cold mountains in East Asia, Northern Australia, India and the Himalayas. Bamboo is broadly grouped into ‘clumping’ or ‘running’ species according to its growth habit. Clumping species have short rhizomes or underground stems (referred to botanically as sympodial); whereas running species have long rhizomes (referred to as monopodial).

The clumping types are more adapted to subtropical and tropical climates and produce tightly packed, compact and larger shoots, up to 5kg while the running types are more suited to cooler climates and produce smaller shoots, usually around 1.5kg. The clumping species suitably adapted for production in Australian include Bambusa oldhamii, Dendrocalamus asper and Dendrocalamus latiflorus. Phyllostachys pubescens is a running species suitable for edible shoot production in Australia. Many of the running varieties are regarded as a weed in Australia and are banned.

Bamboo is one of the fastest growing plants on earth, depending on soil, climate and species. Harvesting of bamboo for shoots can start 3–5 years after establishing a plantation. Bamboo is a shallow-rooted plant and has a high demand for water (greater than 2,000mm per year). Irrigation is necessary where this amount of natural rainfall is not available. The timing of irrigation is important, particularly during the formation of young shoots.

Diseases and pests are not a serious problem with bamboo. However protection of plants against leaf rolling caterpillars may be necessary in the hot, wet season under Australian conditions.

The shoots are harvested from the growing points when they are less than two weeks old. There are three types of shoots: spring or summer shoots, winter shoots and rhizome shoots. The shoots need to be processed by cutting, slicing, boiling and/or canning; and are used in numerous Asian dishes and broths.

Bamboo shoots are classified as an emerging industry in Australia and the industry is much smaller than it was a decade ago with culinary shoots being a niche market. Growers source and sell direct to consumers (primarily food outlets and restaurants) and these markets are quite small and generally well supplied.

The Bamboo Society of Australia promotes all aspects of bamboo interest in Australia. The Australian Commercial Bamboo Corporation represents all commercial bamboo businesses in Australia.

Facts and figures

Bamboo is one of the fastest growing plants in the world
Bamboo is propagated vegetatively in commercial enterprises
Bamboo shoots produced in Australia are consumed domestically
Markets for culinary bamboo shoots may be limited and growers will need to identify and cultivate markets
Bamboo shoots have a short shelf life as they develop bitterness once harvested
Production of bamboo for shoots requires large amounts of summer water – the edible shoots contain 90% water
Production of bamboo for shoots is labour intensive and can be more costly than production of bamboo as a plantation species
Low cost imported product presents the biggest challenge to Australian producers
Some varieties of running bamboo are banned in parts of Australia

Production status

There is small scale commercial production of bamboo shoots in Queensland and the Northern Territory.

The market for fresh bamboo shoots is believed to be very small with only a few growers sourcing and selling direct to buyers, which are primarily restaurants and food outlets.

Map of current and potential growing regions

Uses

Bamboo shoots are used for culinary purposes, as an ingredient in numerous Asian dishes and broths. They are sold fresh, dried and canned. Appropriate processing of bamboo shoots is critical to avoid toxicity (see harvesting and processing section/tab).

Production Requirements

Growing regions

Bamboo varieties grown for culinary shoots generally require tropical to subtropical climates and so are best suited to northern Australia and some parts of northern coastal New South Wales. Temperature, rainfall and water availability need to be carefully considered when selecting the appropriate bamboo species. Gentle slopes facing north east are favourable. Both clumping and running species require shelter from strong winds.

Soil type

Bamboos tolerate most soil types but prefer deep loose, fertile sandy loam with a pH close to neutral. They do not tolerate marshy or waterlogged environments, or very dry, rocky or sticky soil.

Climate

Due to its large number of genera and species, bamboo is adapted to a wide range of climates, however, culinary species (mostly of the clumping varieties) prefer warmer climates where the minimum summer temperatures do not fall below 15°C and with an annual rainfall in excess of 1,400mm.

Varieties

Bamboo is produced vegetatively rather than from seed, propagated from rhizomes and individual stems, which are hollow, emerge from the ground at their full diameter and grow to their full height in a single growing season of 3–4 months. Each new stem grows to its full height of 4.6–12 metres before any branching or leaf production occurs. The branches are produced from the nodes of the stem. As the rhizome matures, the taller stems will be produced.

A large number of bamboo species have been introduced to Australia with only a few suitable for commercial-scale production. Suitably adapted varieties can be purchased from specialist bamboo nurseries throughout Australia.

Clumping species suitable for culinary shoot production in Australia:

Bambusa oldhamii: small diameter shoots (approximately 10cm) weighing approximately 0.5kg, good eating quality and adapted to subtropical regions
Dendrocalamus asper: shoots can reach 30cm in diameter, 30cm in length and weighs 4–7kg; best suited to tropical climates.
Dendrocalamus latiflorus: mature plantations give shoots up to 60cm in length and weighing 3–5kg; adapted to tropical and subtropical environments.

Running species suitable for culinary shoot production in Australia:

Phyllostachys pubescens: shoots range 7.5–15cm in diameter, weighing on average 1.5kg; better suited to temperate regions but is highly invasive and requires careful management to contain.

Planting and crop management

Bamboo is propagated asexually or vegetatively due to the complications of its gregarious flowering nature. Cloned plants can be planted any time throughout the year but late winter or early spring sowing times are favourable. Commercial plantations are generally planted at spacings of between four and six metres depending on the species. Space should be allowed for efficient machinery access.

Adequate water, through irrigation, will be required during the establishment phase (one to two years) when clumps grow vigorously and continuously, producing new shoots during both the wet and dry season.

After this establishment phase, when the clump rhizome has sufficiently developed, shoot production stops during the dry season regardless of irrigation. The clump then commences a yearly growth pattern of extending its network of rhizome axes by producing shoots during favourable environmental conditions (high temperature, high rainfall and humidity) and entering a dormant phase each cool dry season.

Adequate water supply is essential for commercial production and around 2,000–2,500mm annual rainfall is recommended. A combination of rainfall and irrigation can be used. Drip irrigation is commonly used in young plantations moving to spray irrigation in established plantations.

Organic mulching and frequent applications of high nitrogen fertilizer are recommended.

Thinning of culms (individual bamboo stem) that have reached three years is generally done to maintain clump vigour and allow easy access for harvesting of shoots.

Clump thinning is vital to ensure new growth and access into the stands. As bamboo can be a nuisance species, it is important to keep growth under control, especially the running species.

Clumping species mature quicker than running species with the first harvest of clumping species occurring three to five years after planting compared with up to eight years for running species.

Weeds, pests and diseases

During establishment of bamboo it is important to manage any weeds as they will compete with the bamboo for nutrients and water. Mulching or a cover crop can be used for this purpose.

Australia is relatively free from a large number of bamboo pests and diseases. Bamboo mosaic virus is present and is spread by mechanical means. Infection causes hardening of shoots resulting in poor quality product.

Leaf rolling caterpillars have been reported to affect crops during the first rainy season after establishment in the Northern Territory but synthetic pyrethroids can effectively control them. Rats have also been recorded as causing problems in bamboo, nesting around the bases of plants and damaging the rhizomes.

Infrastructure Requirements

Infrastructure requirements for culinary bamboo shoots are similar to other horticulture crops and may include the following:

a tractor
a bed former
irrigation equipment
spray equipment for pesticide application
sharp narrow spades to manually harvest shoots
access to a rapid cooling facility and storage facilities after harvest.

Harvesting & Processing

Edible bamboo shoots need to be crunchy and non-fibrous, the amount of fibre is determined by shoot maturity so timing of harvest is important. Markets prefer shoots that are light in colour with creamy to white flesh as they tend to have lower amounts of bitter compounds and have a more delicate flavour.

Bamboo shoots must be harvested before they emerge from the ground. Shoots of clumping species are harvested by cutting the stems at the point where the softer shoot material joins the woodier rhizome, this point may be 100–200mm below the soil surface. Harvesting running species is similar but the whole shoot is dug from under the ground as the point to be cut may be 15–60cm under the surface. Harvest is carried out by hand using a sharp, narrow ended spade.

Shoots can easily absorb oil so care must be taken around machinery to avoid any contact.

After harvest, shoots need to be pre-cooled using ice baths or evaporative sprays and forced air cooling. The pre-cooled shoots are then washed or brushed to remove any dirt and the base is trimmed and any leaf material removed. Shoots are then packed in 10kg polystyrene boxes and dispatched to market. The cold chain must be maintained at around 2°C from grower to end consumer to ensure a high quality, fresh product. Fresh bamboo must be consumed soon after harvest to prevent a bitter taste developing in the product. Shoots can be canned within 18 hours after harvest to maintain freshness, however the canned product loses its aroma and crunchiness.

Bamboo shoots grown primarily in the tropics contain potentially toxic compounds called cyanogenic glycosides, linamarin and taxiphillin, which break down upon disruption of the plant cells to form hydrogen cyanide. The toxicity of cyanogenic glycosides can be reduced by appropriate preparation of the plant material prior to consumption as food. If bamboo shoots are eaten either raw or after inadequate processing, evidence of toxicity may be observed. For bamboo shoots, slicing into thin strips liberates hydrogen cyanide, which is removed by boiling. The process of canning bamboo shoots liberates and adequately removes hydrogen cyanide.

Markets & Marketing

All bamboo shoots produced in Australia are consumed on the domestic market; the major markets are based in Sydney and Melbourne close to large Asian populations, where there is the largest demand for bamboo shoots. Marketing is usually done through individual contracts between the grower and the wholesaler/retailer.

Growers can also source and sell direct to the restaurant trade.

Risks & Regulations

Risks/challenges

The risks of growing bamboo shoots are the same that a grower of any new crop faces, such as variety selection, production issues and identifying a market. However, the markets for culinary bamboo shoots is very small in Australia and growers are encouraged to thoroughly research the value chain before commencing any production. Extensive effort may be required to secure buyers/markets.

The competition from low cost imported product presents the greatest challenge and risk to commercial bamboo shoot production in Australia. Due to the cost of production, growers may find it difficult to market fresh product against cheaper processed product imported from overseas.

As bamboo shoots are harvested by hand, a significant challenge for Australian producers is competing for international markets with producers who have much lower labour costs.

Regulatory considerations

The standard regulatory considerations that apply to all Australian farms, including laws applying to chemical use and management, occupational health and safety and transport (including machinery movements and the loading/unloading of harvested product), apply to bamboo operations.

As bamboo shoots are marketed with cut surfaces there is a significant risk of pathogen infection and an appropriate quality assurance program should be followed. Some producers of bamboo shoots may choose to participate in Freshcare, which is currently the largest Australian on-farm assurance program for fresh produce for on-farm food safety and quality and environmental certification services. Further information can be found at the websites HACCP and Food Standards Australia New Zealand.

Some varieties of running bamboo are considered a pest and may be banned in some parts of Australia.

Publications

Publications/information

The Australian Bamboo shoot industry: a supply chain approach. RIRDC publication (2005)

New Crop Industries Handbook RIRDC Publication (2004)

Other resources

Freshcare is an industry owned, not-for-profit on-farm assurance program, established and maintained to service the Australian fresh produce industry.

HACCP Australia is a leading food science organisation specialising in the HACCP Food Safety Methodology and its applications within the food and related non-food industries.

Food Standards Australia New Zealand is a bi-national Government agency. They develop and administer the Australia New Zealand Food Standards Code, which lists requirements for foods such as additives, food safety, labelling and GM foods. Enforcement and interpretation of the Code is the responsibility of state and territory departments and food agencies within Australia and New Zealand.

Industry Bodies

Bamboo Society of Australia

Australian Commercial Bamboo Corporation

AusVeg is the national peak industry body representing the interests of Australian vegetable and potato growers and is committed to securing the industry’s future.

Northern Territory Farmers Association is the peak body for the Plant Industry in the Northern Territory and is an amalgam of the former Northern Territory Agricultural and Horticultural Associations.