Macadamia Post-Harvest Systems Expert at Adam Smith International

Cost effective, low maintenance post-harvest systems for macadamia Mid-Sized Farms (Malawi)

Project Background

Malawi Value Chains (MVC), implemented by Adam Smith International (ASI), is one of three components of the Malawi Trade and Investment Programme (MTIP), a five-year FCDO-funded initiative which aims to break Malawi’s cycle of low growth through driving exports. The overall objective for MVC is to implement the value chain component of MTIP with the goal to increase the productivity, quality production and export performance of the macadamia and mango value chains, as well as support increased mining investment and ultimately exports. Other complementary MTIP components are focused on increasing access to patient capital and cutting the time and costs of trade and logistics (the latter implemented by TradeMark Africa [TMA]).

Assignment

A review of the macadamia production system has identified drying and post-harvest handling as having a substantial influence on quality and market access. Many of the macadamia farmer co-operatives organisations (FOs) and mid-size farms (MSFs) are unable to store and dry nut in the optimal manner to preserve quality, which in turn leads to sub optimal returns. The inability to effectively store and dry nut results in higher risk of rejection and increases cost of processing which erodes margins at farm level. Large farms have installed Nut in Shell (NiS) handling lines that require significant power and skill to operate. These systems are unlikely to be success in the majority or MSF farms and FOs, so alternatives are required.

Macadamia is aggregated into factory consignments of more than 4MT and requires 2-4 weeks to dry (ambiently). This can take several weeks for an MSF or FO to reach the minimum volume for a consignment to factory particularly in early stages of the season. This makes investment in some form of infrastructure to store and dry nut essential to quality, pricing and marketing. The more successful MSFs conduct the initial processes in simple drying sheds, usually equipped with drying racks made from chicken wire and an elevated ‘bed frame’ structure.

Macadamia drying is an important phase for quality. It takes fresh nut from 20% moisture to 10% or less. This stabilises the nut so that impact during transport does not damage the kernels. It also minimises rancidity and germination that occurs if fresh nut is poorly stored.

There are a significant number of MSFs coming into production, typically in the 5-8 ha range, but many have not fully considered post-harvest handling and there are no standard designs available. MVC is engaging with around 50 macadamia MSFs ranging from 3 – 40ha to provide farm planning and training to take the right strategic decisions when investing in or expanding a farm. Through these conversations and farm visits many MSFs recognise the value of investing in post-harvest infrastructure that enable larger and more consistent factory consignments of higher quality, but these need to be cost effective and appropriate to their operations.

This assignment would review the drying racks and systems currently used by MSFs, as well as research online for appropriate systems and design a cost-effective off-grid drying and storage system that can dry and store nut in larger quantities, ideally made from locally sourced lower cost materials. MVC seeks the skills of an experienced engineer to develop a design for a modular / scalable drier capable of storing from 4 to 50 mT of nut.

Initial work has identified technical gaps where greater understanding is sought and specific designs are required:

i. Designs for macadamia driers using local available, lower cost materials. The building should be free standing and not situated inside a dedicated shed/ warehouse and require the following elements.

• Intake/ dehusking area
• NIS storage (racks/ bins)
• Drying system (energy source)
• Quality testing area
• Power (generator set to power husking, solar to power lights/sockets), which needs to be off-grid

ii. Review of existing small-scale designs in use in Malawi to recommend design improvements

iii. Recommended standardised designs for cost effective drying solutions for macadamia

The assignment will be delivered in close collaboration with the MVC agribusiness team and network of MSF.

Assignment Objectives

 

• Develop a standardised design(s) for development of post-harvest infrastructure capable of handling 4-50Mt of NIS for MSFs and FOs.
• Design to have four (modular) components – post harvest handling centre, drying system, NIS storage system and supporting systems. The design needs to be cost effective and largely constructed from locally available materials
• Activities and Deliverables

The consultant will contribute to the following activities and deliver following outcomes:

Activity Responsibility Action points Deliverable

 

• Develop macadamia post-harvest centre design specification Consultant, MVC
• Capture specifics of the required design in discussion with MVC
• Consult MSF and be aware of context Design specification detailing (building needs, power options, drying options)
• Design drying system Consultant
• Develop a design for a simple cost-effective drying system that can meet the specification in 1. above
• Identify materials,
• Determine energy needs/ source options and best choices
• Identify suppliers of specialist materials Design & BoQ for drying system
• Design NIS Storage System Consultant
• Develop design for a scalable NIS storage system
• Identify materials,
• Identify suppliers of specialist materials Design & BoQ for storage system
• Design of supporting systems & capabilities Consultant
• Power needs/ source
• Intake and dehusking area layout
• Recommendation for dehusking equipment (to gauge power demand)
• Building/ structural/ layout recommendations Building design including the identified aspects
• Test design through application at minimum of 2 MSF Consultant/MVC
• MVC approves selection of farmers and consultant/MVC negotiate with the farmers on their contribution
• Adapt the standardised designs as appropriate
• Hand over to the farmers
• Review process and set programme for determining performance Set of 2 designs instructions on how to adapt the design for other farms

Timing and Duration

The assignment should commence on the 14th April to be completed by 9th May 2025 with an estimated LOE of up to 16 working days

Activity Responsibility Timeframe LOE (Days)

Develop macadamia post-harvest centre design specification, short report Consultant 16th April 1

Drying system design Consultant 25th April 3

NIS storage system design Consultant 25th April 3

Supporting systems & capabilities Consultant 25th April 3

Test design through application at two MSFs Consultant 9th May 6

Total Up to 16

Qualifications

The selected consultant will require the following expertise:

• Over 10 years’ civil engineering experience in the design of agri processing buildings including farms in the target range
• Demonstratable knowledge of macadamia NIS handling through the design of structures and the stages required to maintain quality.
• Understanding of the Malawian agricultural context and the needs of MSFs and FOs.
• Familiar with materials are readily available in Malawi to inform design considerations

Payment Terms & Schedule

Payment will be upon approval of all deliverables for actual days worked – up to 16 days at the agreed daily rate. Time entries detailing work completed per day will be submitted through the ASI OS.