OptiCor achieves a yield of 95% or higher in iceberg lettuce through precision coring

Efficient use of raw materials is a key consideration in iceberg lettuce processing. To reduce the amount of product discarded when the core is removed, Sormac developed the OptiCor OC-60, a machine that combines camera-assisted positioning with a conical coring system and depth control.

OptiCor processes lettuces measuring between 90 and 220 mm in diameter and can reach a maximum capacity of 2,100 pieces per hour. After coring, the machine can also be fitted with an optional unit that divides each lettuce into two or four pieces without reducing processing capacity.

Coring adapted to each lettuce

The lettuces are placed manually in the machine’s pockets or fed by the optional OCS automatic feeding system. Using the image provided by the camera, the operator positions each lettuce with the core facing downwards.

The system identifies the position of the core and checks whether it is within the set tolerance. It also measures its dimensions and calculates the appropriate cutting depth. Based on this information, the conical blades adapt the coring process to the characteristics of each lettuce.

This configuration achieves positioning accuracy of 99.9% and a product yield of 95% or higher. Because coring is carried out from below, the extracted core remains separate from the product intended for consumption.

The pockets are made of stainless steel, so no plastic is introduced into the product flow. The machine also features a digital control panel and has been designed to facilitate access for cleaning and maintenance. The coring blades and those in the optional cutting unit can be replaced within a few minutes.

From eight to two operators per line at Nature's Way Foods

Natures Way Foods has installed OptiCor at its facility in Runcton, Chichester, United Kingdom. The site specialises in fresh prepared foods and processes several million iceberg lettuces each week, a volume that almost doubles during peak periods.

Before the machine was introduced, eight people were responsible for removing the outer leaves, cutting out the core manually according to a set pattern and inspecting each lettuce. In addition to the cost of this operation, the company found it difficult to recruit and retain the required workforce.

Natures Way Foods was able to test OptiCor before purchasing it and share its observations with Sormac’s engineering team. This process led to adjustments aimed at enhancing reliability and performance and achieving optimum throughput. After evaluating the first machine in production, the company purchased three additional units.

With the semi-automated system, the facility now requires two people per line instead of eight. Brett Beveridge, Engineering Director at Natures Way Foods, also highlights the machine’s compact footprint, ease of operation and cleaning, and the uniformity and precision provided by the vision technology.

OptiCor therefore focuses waste reduction on a specific operation: adapting the coring process to each lettuce so that the core is removed without discarding more product than necessary.