Conductive Food Package Rethermalization for Uniform Dual-Sided Heating

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing food rethermalization techniques face challenges such as inability to impart unique thermal treatment to separate food bags, uneven or uniform thermal treatment throughout the food thickness, and inefficiencies in maintaining food quality due to contamination and energy consumption.

Innovation Solution

A method and apparatus using opposing heating mechanisms in conductive heat transfer contact with food packages to rethermalize and hold at selected temperatures, allowing for precise control of temperature and time profiles to ensure uniform heating and extended food quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If water bath heating is used, then food packages can be heated, but water supply lines, drain lines, steam venting, and regular cleaning are required

Engineering Contradiction:

Improvefood heating capabilityVSAvoidwater supply lines, drain lines, steam venting, cleaning requirements

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The patent removes the water bath medium entirely from the heating system. Instead of heating food in water, the invention uses direct electrical heating elements that contact the food package directly, eliminating the need for water supply lines, drain lines, steam venting, and cleaning requirements while maintaining the food heating capability

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the thermal convection mechanism of water bath heating with direct electrical conduction heating. Electrical heating elements directly contact the food package and transfer heat through conduction, substituting the complex water circulation and steam generation system with a simpler electrical heating system

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Productivity

If common chamber heating is used, then multiple food bags can be heated simultaneously, but unique thermal treatment cannot be imparted to separate bags

Engineering Contradiction:

Improvesimultaneous heating capabilityVSAvoidunique thermal treatment for separate bags

Core Design Contradiction:

ProductivityVSAdaptability or versatility

Solution Approach 1:

The patent divides the heating system into separate independent heating chambers or zones, each capable of heating individual food packages. This segmentation allows each bag to receive unique thermal treatment through independent temperature and time control while still enabling simultaneous heating of multiple packages in different chambers

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent implements local quality control by providing independent temperature and heating parameter control for each heating zone or chamber. Each food package can be subjected to customized thermal treatment conditions (different temperatures, times, or heating rates) tailored to its specific requirements, while maintaining the ability to heat multiple packages simultaneously in separate zones

Inventive Principle:

Principle #3Local quality

3Speed

If infrared or microwave heating is used, then heating speed is improved, but uniform thermal treatment throughout food thickness cannot be achieved

Engineering Contradiction:

Improveheating speedVSAvoiduniform thermal treatment throughout food thickness

Core Design Contradiction:

SpeedVSManufacturing precision

Solution Approach 1:

The patent combines multiple heating elements positioned on opposite sides of the food package, applying heat simultaneously from both surfaces. This dual-sided heating approach maintains high heating speed while ensuring uniform thermal treatment throughout the food thickness by eliminating the temperature gradient that occurs with single-sided heating methods like infrared or microwave

Inventive Principle:

Principle #5Merging (Combining)

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

The solution achieves efficient and uniform rethermalization with improved energy usage, maintaining food quality by preventing contamination and oxidation, and allowing for flexible temperature control in each compartment.

Implementation Method 1

moving the first heating mechanism toward the second heating mechanism to bring the heating mechanisms into conductive heat transfer contact with respective first and second surfaces of the package

Methodology Applied

Scientific EffectConductive heat transfer: Conduction (thermal)

Data Source

PatentUSRE45789E1Rethermalizing apparatus

Publication Date: 2015.11.03 DUKE MANUFACTURING CO

AI summary

Apparatus for and methods of rethermalizing a package of refrigerated or frozen food are disclosed. In general, heating mechanisms are brought into conductive heat transfer contact with the package of food and operated for a duration of rethermalization time to rethermalize the package of food by heating the food to a rethermalized temperature, and then, if desired, to hold the rethermalized package of food at a desired holding temperature for a duration of holding time. The rethermalization time can be relatively short (e.g., thirty minutes or less), and the holding time can range from a very short period of time to a very long period of time (e.g., four, six, eight or more hours) without significant loss of food quality. Other features of the apparatus and methods are disclosed.