Two-Step Insect Cooking for Spore Elimination and Color Preservation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for processing insects for food or feed production fail to effectively eliminate resistant pathogens like Bacillus cereus spores and often result in discoloration, which are critical for food safety and appearance.

Innovation Solution

A two-step heating process involving temperatures of 40°C to 105°C with specific durations for each step, combined with cooling and fluid handling, to activate and inactivate pathogens while minimizing discoloration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single high-temperature cooking step is used to kill pathogens, then pathogen elimination is effective, but resistant spores survive and product discoloration occurs

Engineering Contradiction:
Improvepathogen elimination effectivenessVSAvoidresistant spore survival and discoloration
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The cooking process is divided into two distinct steps: a first cooking step at a lower temperature (40-105°C) for a longer duration to activate spores without causing excessive discoloration, followed by a second cooking step at a higher temperature to eliminate both vegetative pathogens and activated spores. This segmentation allows each step to target specific aspects of pathogen destruction while minimizing negative effects on product appearance.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first cooking step performs a preliminary action by activating resistant spores into vegetative cells at a controlled lower temperature. This preliminary activation converts the highly resistant spore form into vulnerable vegetative cells, which are then easily eliminated in the second cooking step. This preliminary action makes the final pathogen elimination more effective while avoiding the need for prolonged high-temperature exposure that causes discoloration.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If heating temperature is increased to kill resistant spores, then pathogen elimination improves, but product quality and color are degraded

Engineering Contradiction:
Improveresistant spore eliminationVSAvoidproduct color and appearance quality
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The heating process is segmented into two temperature zones: a first zone (40-105°C) that preserves product color while activating spores, and a second zone (higher temperature) that eliminates activated spores. This segmentation allows the majority of the treatment time to occur at lower temperatures, preserving product appearance, while still achieving complete spore elimination in the final step.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The process utilizes parameter changes by varying both temperature and time across two distinct heating phases. The first phase uses lower temperature (40-105°C) with longer duration to activate spores without significant discoloration, while the second phase uses higher temperature with shorter duration to eliminate activated spores. This dynamic parameter adjustment optimizes both pathogen elimination and product quality preservation.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Effectively eliminates resistant pathogens and preserves the appearance of insects, ensuring a safer and more appealing food product.

Implementation Method 1

the first heating step is preferably performed at a temperature of 75°C to 105°C and preferably has a duration of 5 to 15 minutes, more preferably 8-12 minutes. In the first heating step - besides inactivation of vegetative microorganisms and the larvae itself (if provided alive) - the resistant forms of the pathogens, namely spores, are activated, so that they will germinate and become vegetative cells after cooling.

Methodology Applied
Scientific EffectSpore activation through heating: Heating

Implementation Method 2

The cooling step is preferably performed at a temperature of 10°C to 30°C, more preferably 20-25°C and preferably has a duration of 10 to 45 minutes, more preferably 25-35 minutes. After cooling activated spores to a certain temperature range, they germinate and become vegetative cells after a certain time.

Methodology Applied
Scientific EffectSpore germination through cooling: Cooling

Implementation Method 3

The second heating step is preferably performed at a temperature of 75°C to 105°C and has a duration of 10 seconds to 5 minutes, preferably, 10 seconds to 1.5 minutes. In the second heating step the vegetative cells of pathogens resulting from spore germination during cooling are inactivated.

Methodology Applied
Scientific EffectPathogen inactivation through heating: Heating

Data Source

PatentEP4218423B1Two-step cooking
Publication Date: 2025.09.17 BUHLER AG
  • EP4218423B1 patent drawingFigure 1
  • EP4218423B1 patent drawingFigure 2

AI summary

The present disclosure relates to a method and a system for processing insects or insect larvae. The method comprises a first heating step of heating the insects or insect larvae in a first fluid at a temperature of 40°C to 105°C, a cooling step of cooling the insects or insect larvae in a second fluid and a second heating step of heating the insects or insect larvae in a third fluid at a temperature of 40°C to 105°C, wherein the second heating step is performed after the cooling step.