NUT PRODUCTION

Lesson Structure

There are 8 lessons in this course:

1. Introduction
   • What is a Nut
   • Identifying Plants Accurately
   • Classification of Nuts into their Plant Families
   • Juglanaceae,
   • Coylaceae,
   • Fagaceae,
   • Burseraceae,
   • Lecthidaceae
   • Sterculiaceae
   • Rosaceae
   • Pinaceae
   • Anacardiaceae, etc
   • Review of Botany of Nuts: flowers and fruit development
   • Resources
2. The Most Commonly Grown Varieties
   • Overview of Nut Culture
   • Comparing most common nuts
   • Terminology
   • Almond
   • American Hazlenut
   • Cashew
   • Peanut
   • Walnut
   • Macadamia
3. Culture of Nuts
   • Site Selection and Management
   • Soils
   • Soil Testing
   • Water Management
   • Nutrition and Feeding
   • Plant Health: pest and disease, protection from wind, salt, air, etc
   • Common problems with different types of nuts
   • Planting
   • Terminology
   • Weed Management
   • Pruning
4. Less Common Nuts
   • Pecan
   • Pistacio
   • Pine Nuts
   • Auraucaria
   • Chestnut
   • Filbert
   • Brazil Nut
   • Beech
   • Oak
   • Sunflower
   • Pili Nut
   • Cola Nut
   • Cocao
   • Hausa Groundnut
   • Acacia, and more
5. Propagation
   • Seed Propagation of Nuts
   • Cuttings
   • Layering
   • Grafting
   • Propagating Corylus
   • Propagating Pinus
   • Propagating aids and structures
6. Harvest and Post-harvest of Nuts.
   • Harvesting
   • Cleaning, Cracking and Shelling
   • Drying and Storage
   • Handling Almonds
   • Cashews
   • Chestnuts
   • Pine nuts
   • Walnuts
   • Hazlenuts
   • Pistacios
7. Marketing Nuts
   • Overview
   • Where to sell nuts
   • Marketing Processes
   • Market Research
   • Uses of Nuts: Food and other uses
8. Workplace Health, Safety and Risk Management
   • Duty of Care
   • Risk Assessment in a Horticultural Enterprise
   • Financial Risks
   • Keeping the Workplace Safe
   • Protective Clothing
   • Equipment Safety (Tools and Machinery)
   • Safety with Manual Handling and lifting

Aims

• Identify different nut crop varieties.
• Determine the cultivation practices appropriate to a range of different nut crops.
• Determine how to propagate a range of different nut plants.
• Determine appropriate techniques for harvesting a nut crop.
• Specify an appropriate post-harvest treatment for a nut crop.
• Develop marketing strategies for nuts.

What You Will Do

• Here are just some of the things you will be doing:
• Distinguish between common and scientific perceptions of the term nut.
• Compare the botanical characteristics of the fruits from different nut genera.
• Describe the botanical classification of different species of nut plants, including where appropriate, botanical interrelationships.
• Prepare a plant collection of different nut varieties, including the following details on each plant:
  • Plant names (Common and scientific)
  • A photo, illustration or pressed specimen
  • Cultural details
  • Harvest & Post-harvest
  • Uses (eg. valuable products).
• Develop a resource file of information relevant to the nut growing industry, including:
  • Suppliers of nut plants
  • Trade or grower associations
  • Publications
• Perform simple tests on three different soils to determine:
  • Soil type
  • pH
  • Drainage
  • Water holding capacity
• Test and evaluate different soils to determine nut varieties suitable for growing in each.
• Explain soil management requirements for at least ten different nut varieties, including:
  • Nutrition
  • Soil structure
  • Physical attributes
• Explain the control of different pests and diseases on different nut varieties.
• Develop guidelines for the culture of a specified variety of nut, in your locality, including:
  • Watering
  • Weed control
  • Soil management
  • Fertilising
  • Pest control
  • Disease control
• Prepare a twelve month plan for cultural practices on a specified nut plantation.
• Explain different methods of propagating different nut species, including:
  • Seed
  • Grafting
  • Layering
  • Cuttings
• Determine propagation methods for ifferent nut species, including where applicable, rootstock variety names.
• Demonstrate how to prepare cuttings for dfferent nut species.
• Demonstrate three different types of grafts, suitable for propagating nut varieties.
• Determine seed germination procedures for different nut genera.
• Prepare a production schedule, for nursery production of a specified type of nut.
• Propagate different nut plant varieties.
• Explain the operation of a mechanical harvester which can be used for nuts.
• Determine when to harvest different specified nut species.
• Compare the efficiency of four different techniques for harvesting nuts.
• Describe two different storage techniques for a specified nut variety.
• Determine the optimum environmental conditions for the storage of different nut species.
• Evaluate three different samples of nuts, which have been stored using different techniques.
• Determine the commercial processing techniques used for five specified nut species.
• Explain post-harvest handling of a specified nut species, by a commercial plantation in a specified locality.
• Determine different ways in which nuts can be consumed.
• Compare different ways nuts are packaged for retailing, with reference to different factors including:
  • Physiological impact on the nut
  • Cost of packaging
  • Presentation
• Explain the marketing of two different specified nut products, in a specified locality.
• Develop a marketing plan for one specified type of nut.
• Plus - Special Assignment - PBL Project Develop a plan for growing selected varieties of nuts in a specific location

Indehiscent simply means that the fruit does not break open readily and release the seed of its own accord.

The seed and the fruit of a nut is one and the same ie. one cannot be removed from the other. True nuts are produced by – the oak (Quercus), chestnut, filbert, hickory, macadamia, hazelnut and others.
Whereas the seeds of some plants we think of as nuts (such as almonds, walnuts and coconuts), are actually the seeds of ‘drupe’ fruits ie. contained within the fruit of the plant (and therefore not ‘true’ nuts). Cashews are actually the seed of the plant, and the peanut (to complicate matters), is not actually a nut but a legume (like peas and beans).

(Note: legumes such as wattles or peas in contrast to indehiscent fruit are dehiscent fruits ie. they dry, and then drop seeds while the dry fruits are still attached to the plant).

Horticulturists and nut growers be less rigid in the way they define a nut. Generally speaking nuts are edible fruits or parts of fruits which are hard, relatively dry (unlike fleshy fruits), and are able to be roasted for eating, or in many cases, may be eaten fresh. In some cases, the roasting may destroy undesirable chemicals in the nut, or may enhance the flavour.

In the strict botanical sense, a peanut would not be a nut, because there can be more than one seed inside a fruit; however peanuts are perhaps the most widely grown commercial nut in the world.

Nuts (above all) have a distinct advantage over other fruits in their keeping quality. Being a dry product, they are less susceptible to spoilage, and will generally store well without any sophisticated or expensive storage treatments. This characteristic alone extends their marketing life, and can eliminate many problems associated with other types of crops. (Note: they may need protection from pests though (eg. rodents and other vermin).

These and other reasons impact upon the ways in which different nut species are harvested.

Examples

Drying and Storage
Many nuts can lose their taste, become contaminated by disease (e.g. fungal rots) or deteriorate in other ways if they are not dried and stored properly. Nuts with higher oil content can deteriorate faster than those with less oil. Walnuts and chestnuts deteriorate faster than almonds and pistachios.

Nuts that are stored in the shell need to be stored at low temperatures. Storing nuts in the shell can help protect them from contamination and deterioration. A hard shell can keep out contaminating aromas (such as paint, petrol or even other foods). Hard shells also deter attack by insects or other pests.
Storing nuts in a refrigerator may extend their life; as does storing them in an air tight container.  This may be more important in a warm or humid climate.

De-husking (i.e. removing kernels from the husk or shell) is largely carried out using machines or specialised equipment for commercial nut production. Hand processing may be used for smaller scale operations.  Many nut species have a fleshy fruit (dried or otherwise) that adheres to the outside of the nut. In some species (e.g. almonds), this tissue tends to split and come away from the hard nut easily. This material needs to be removed from the nut either by hand or machine.
For some nuts (including walnuts), delaying de-husking can result in a deterioration of nut quality; but for others the quality is unaffected.

Nuts have traditionally been sun dried after harvesting and removing any remaining tissue clinging to the husk.  Some nuts may be dried while still in the shell, others are removed from the shell and dried. Drying in the sun has risks: rain or high humidity can be a problem. If the weather is hot and dry though, nuts may only need 2 to 3 days to dry in the sun. If weather is overcast, wet and not so hot, it may take up to 3 weeks or more for nuts to sun dry.

Large scale commercial operations now tend to dry nuts using artificial fan forced heat in specially built driers; which can process nuts on multi layered drying racks with a drying time of between 12 and 24 hours. In Europe chestnuts are dried using a wood fired kiln.

Some nuts are bleached to improve their appearance before marketing. Bleaching, may for instance, involve dipping nuts for 4 minutes in a sodium hypochlorite solution (2% active chlorine). Sulphur dioxide has also been used to treat nuts (more in the past than now though).

Toxins
Many nuts will contain unpalatable or even toxic chemicals when they are first harvested; and these chemicals need to be removed before they are eaten.
Two common ways of removing these chemicals are washing or soaking the nuts, or by cooking the nuts; cooking nuts reduces any terebinthine or turpentine taste; which can be a problem in some raw nuts. For example cashew nuts have a caustic sap in the fruit that can sometimes find its way onto the nut; but with cooking, that caustic material is removed.