How to make insect meal more economically viable in agriculture?
Introduction
In the previous post, I briefly explained about the market prospects of insect meal, and why insect meal should be utilised to improve the productivity of our agriculture by being a key agriculture commodity in a circular economy. In this post, I will elaborate in more details the prospective steps that can be taken to increase its commercial viability. To make insect meal more economically attractive and scalable, it is imperative to improve on value chain management and to reduce post-harvest processing costs.
To be insect meal producer or animal feed producer?
While insect meal is integral to circular economy, it is also critical that insect meal producers understand their own role in the animal feed value chain. Animal feed producer is further down the value chain relative to insect meal producer. Insect meal producers have to work closely with animal feed producers to get the nutritional profile of animal feed right. Animal feed producers would already understand the nutritional profile needed for various kind of livestock, a knowledge set necessary to make compound feed that meets the dietary requirement of a target animal. Alternatively, insect meal producer can also become animal feed producer themselves, thus becoming slightly more vertically integrated in value chain. Marketing strategy would thus be different. Insect meal producers would have to market their product to animal feed producers; whereas if insect meal producers themselves also decide to be animal feed producers, their product would then be marketed to livestock farmers.
Homogenous waste or not?
While insects can feed on a wide variety of food and agricultural wastes, for optimisation of cost and value chain management however, it is usually better for meal producers to farm insects using homogenous waste (or similar type of substances). Homogenous waste reduces sorting costs and also for improved management of quality control. The reason is due to the following:
“Livestock farmers require insect meal with constant nutritional profile. Otherwise, livestock which depends on insect meal, can experience different maturation rate, growing rate, and under-nutrition. This will negatively impact economic livelihood of livestock farmers.”
Post-harvest value chain and processing
It is usually better for post-harvest processing to be as close to possible to insect farms. Water removal is integral in post-harvest operation. That is because water constitutes to more than 60% of its body weight in water. Without first removing the water, significant bulk of logistic would actually be moving water around.
Many current post-harvest processing methods (especially water removal) are making insect meal about USD$800–1000 per dry tonne more expensive that it can be. There are a couple of factors that resulted in the aforementioned circumstance. One of which is due to the inverse relationship between capital expenditure and operating cost; wherein, the general rule of thumb is that cheaper industrial technologies tend to have higher operating cost, while more expensive industrial technologies have lower operating cost. As insect meal is a relatively new market, many producers are still utilising post-harvest technologies that are low in capital expenditure to test the readiness of the feed market. However, these technologies tend to have higher operating cost.
How to make insect meal USD$800–1000 per tonne cheaper?
Many of the conventional post-harvest technologies (especially dryers) are using electricity. For drying purposes, every kwh (a unit for energy measurement) in electricity is at least 1.5 times more expensive than natural gas and diesel. To justify investment into technologies with lower operating cost but higher capital expenditure, economies of scale would be necessary and also for the post-harvest technologies to operate on more than just one 8-hour shift per day. (Note: Caution should be given to using diesel for direct heating and drying, as there could be smell of diesel in the final insect meal. This problem can be solved using indirect heat exchange, although may reduce energy efficiency slightly)
Drying time must also be very short. The longer the drying time (especially at lower temperature), the more energy inefficient the drying operation becomes, as a lot of waste heat is created. Waste heat is heat that can no longer be recovered for good use, like those coming out from exhaust of a car, or exhaust of cooking fume hood. For a typical conventional electric oven (status quo operation), drying time can be in excess of 5 hours. That is non-stop more than 5 hours of waste heat being generated. Also, longer drying time induces oxidation onto bioactive compounds which are not desirable for optimum product quality.
Drying time can be reduced by making meal particles small (higher surface area per unit volume) and/or increasing drying temperature. A general rule of thumb is that for every 10 degree Celsius rise in drying temperature, energy efficiency increases by about ~3–5%. (Note: For an analogy to higher surface area per unit volume, if you have one litre of water left inside a bottle with no cap on and a litre of water spilled on the floor, the one on the floor will dry out first if both are left unattended. The area of water on the floor left exposed to air is significantly bigger than in an open bottle).
Concluding remarks
This post is meant to give readers a better insight into a whole new market and value chain. For better insight into the sustainable role that insect meal plays in the fish feed industry, please do refer to “Can fish feed be environmentally sustainable?”.
“This article is co-written by Dr. Daniel Mahadzir”
