How does machine harvesting affect blueberry sorting?

When you switch to machine harvesting, you solve the biggest problem in the industry over recent years – the shortage of labour. A harvester picks as much as ten people, and doesn’t ask whether you’ll find workers in June. The trouble is, the fruit coming off the machine looks different from hand-picked berries. And if you don’t address that before packing, you’ve traded a labour problem for a complaints problem.

Product quality drops: fruit arrives more bruised

With hand harvesting, fruit goes straight into the punnet. With machine harvesting – it’s shaken off, drops, travels along a belt, waits for transport. Each of those moments is a micro-impact. Blueberries don’t show it straight away, but later, in the packaging on the supermarket shelf, they leak juice, soften, lose firmness faster. These are the fruit that trigger a call from the supermarket with a complaint.

Softer, bruised fruit is simply the reality of machine harvesting. What can you do about it? Two things. First, catch the ones that are already too soft before they reach the packaging. Second, avoid adding further damage during automated packing. A sorter that drops fruit from height and rotates it mid-air adds damage to a product that has already taken a beating in the field.

A harvester doesn’t pick and choose – it takes everything

A picker’s hand skips over green and undercoloured fruit. A harvester shakes the bush and takes whatever falls – ripe, red, green, all in one pass. The proportion of unripe fruit in machine-harvested crop can be several times higher than with hand picking. And every unripe berry in a punnet brings down the grade of the entire batch.

Batch quality swings from hour to hour

After the harvester, the incoming crop is not uniform. Different quality in the morning, different in the afternoon, different from a younger plantation, different from an older one. That means the sorting settings that worked at eight o’clock are either letting too much through or rejecting good fruit by three.

Where does the MXM BN.2 blueberry sorter fit in?

The MXM BN.2 is designed for one fruit – blueberry – and for exactly this situation: lower-quality, non-uniform crop after machine harvesting. Here is why our optical blueberry sorter is the right fit for machine-harvested fruit. MXM BN.2 blueberry sorter:

• sees the fruit from both sides, every time. Two cameras (RGB and NIR) – one from above, one from below – scan every berry regardless of how it has landed. We don’t assume the fruit will rotate and reveal a defect, because in practice it doesn’t. With machine-harvested fruit, where bruising can be on any side, visibility from both sides makes a real difference – one you will notice in your complaint rate.

• rejects unripe and overripe fruit. You set separately how aggressively the machine removes green fruit, how it handles red fruit, and separately – through near-infrared analysis – fruit that is too soft or bruised. These are the four sliders on the HMI screen that an operator learns in a single day.

• adapts automatically to variable batches. The Adaptive Soft Detection (ASD) function adjusts the softness threshold to match the current fruit, batch by batch. You don’t need to stand at the machine and change settings as incoming quality shifts. It also removes the problem of undertrained operators, because everything happens automatically.

• doesn’t bruise delicate fruit. One of the lowest drop heights on the market – around 160 mm – with no rotation. Instead, a channelled TPU soft-material belt. Fruit that has already taken a hit in the field doesn’t get hit again on your line.

• handles fruit without bloom. After machine harvesting and long transport, fruit often loses its natural waxy bloom – and that confuses standard cameras. The MXM BN.2 uses a polarisation filter that reduces reflections, so it sorts accurately even where the bloom has worn off.

• is quick to clean. The open construction means the machine can be thoroughly washed in around 20 minutes, instead of losing several hours to the process.

We have proof that the MXM BN.2 sorter works

In trials, with a very difficult incoming crop – one in four berries defective on entry – the machine eliminated 88-92% of defects. With better quality fruit, the results are higher. Customers already running the MXM BN.2 have seen its performance first-hand – including Berritum, a blueberry exporting company.

We believe in practice over promises. The best proof of how a blueberry sorting machine performs is not a brochure – it’s a trading company already running our sorter. If you’re planning to move to machine harvesting, or you’re already harvesting and seeing what arrives at the packhouse – fill in the form and we’ll connect you with someone sorting the same fruit as you.

FAQ — machine harvesting and blueberry sorting

Why does machine-harvested fruit need different sorting than hand-picked blueberries? Because what comes off the harvester is a different fruit. With hand picking, the picker skips the green and unripe berries, and the fruit goes straight into the crate. The harvester shakes the bush and takes everything that falls – ripe, red and green in one go – and along the way the fruit is shaken, drops and travels along the belt. The result is a more bruised, less uniform intake that has to be inspected more thoroughly at the sorting stage, so that a labour shortage doesn’t turn into a complaints problem.

Does machine harvesting lower blueberry quality? The harvesting itself doesn’t spoil the fruit straight away, but every shake, drop and pass along the belt is a micro-impact. The blueberry doesn’t show it immediately – only later, in the punnet on the shop shelf, does it release juice, soften and lose firmness faster. These are the berries that get the supermarket calling with a complaint. That’s why machine harvesting calls for two things: catching the berries that are already too soft before they reach the packaging, and not adding any damage during packing.

Why is there more unripe fruit in the intake after machine harvesting? Because the harvester doesn’t choose. The picker’s hand skips the green and unripe berries, while the machine shakes the bush in one motion and takes whatever falls. The share of unripe fruit in machine-harvested intake can be several times higher than with hand picking – and every unripe berry in the punnet lowers the grade of the whole batch. That’s why the sorter has to reliably tell apart and reject green and red fruit.

Why do sorter settings have to change during the day with machine harvesting? Because machine-harvested intake isn’t uniform – the quality is different in the morning, different in the afternoon, different from a younger plantation, different from an older one. A sorting setting that was right at eight o’clock is already letting too much through or throwing out good fruit by three. The answer is a sorter that adjusts the sorting threshold to the current batch by itself, instead of requiring the operator to stand by the machine and correct the settings manually.

Which sorter works best for machine-harvested blueberries? One that’s designed for a single fruit and for the poorer, non-uniform intake that comes off the harvester. In practice that means four things: seeing the fruit from two sides (because the bruises can be anywhere), adjusting automatically to a variable batch, handling already-bruised fruit gently, and coping with fruit that has lost its waxy bloom. The MXM BN.2 combines these: two cameras, RGB and NIR (one above, one below), the Adaptive Soft Detection function, a drop of around 160 mm with no turning of the fruit, and a polarisation system that reduces reflections.

How does the sorter avoid adding damage to already-bruised fruit? By minimising drops and not turning the berry. A sorter that throws the fruit from a height and spins it mid-air adds damage to a product already battered in the field. The MXM BN.2 has one of the lowest drops on the market – around 160 mm – and guides the fruit along a tunnelled belt made of gentle TPU material, without turning it. Fruit that suffered in the field doesn’t take a second hit on your line.

Can the sorter cope with blueberries that have lost their waxy bloom? Yes, provided it has the right optical setup. After harvesting and long transport, the fruit often loses its natural waxy bloom, which confuses ordinary cameras – a rubbed-off bloom produces reflections that distort the image. The MXM BN.2 has a polarisation system that reduces these reflections, so it sorts accurately even where the bloom is rubbed off.

How effective is the MXM BN.2 sorter on a difficult harvester intake? In trials on a very difficult intake – one in four berries defective at the input – the machine removed 88-92% of defects, and correspondingly more with better intake. Its effectiveness is confirmed by companies already running the MXM BN.2, including the blueberry exporter Berritum. The best proof isn’t a leaflet, but a trading company already sorting the same fruit – which is why we offer to put you in touch with a customer working on this sorter.