Glucono Delta Lactone pH Control at Dual Water Activity Interfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Compositions with high and low water activity (Aw) portions in contact with each other risk microbial growth due to pH changes, leading to reduced shelf life unless maintained separately.
Innovation Solution
Incorporating glucono delta lactone (GDL) in the low Aw portion allows it to convert to gluconic acid at the interface with the high Aw portion, reducing the pH and inhibiting microbial growth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a high Aw composition with low pH is contacted with a low Aw composition with higher pH, then the low Aw portion provides structural support or flavor, but the pH at the interface increases causing microbial growth risk
Solution Approach 1:
GDL is pre-positioned in the low Aw portion before contact with the high Aw portion. Upon contact, GDL immediately begins converting to gluconic acid at the interface, proactively establishing a low pH environment before microbes can grow. This preliminary placement of the pH-control mechanism resolves the contradiction by ensuring pH stability is activated exactly when and where needed.
Solution Approach 2:
GDL acts as an intermediary substance that mediates the pH interaction at the interface. It converts to gluconic acid in response to water from the high Aw portion, creating a buffer zone that prevents direct pH destabilization. This intermediary conversion process maintains pH stability while allowing the two different compositions to remain in contact.
2Reliability
If GDL is added to the low Aw portion to reduce interface pH, then microbial growth is inhibited, but the low Aw portion's original pH and flavor profile may be affected
Solution Approach 1:
GDL is distributed throughout the low Aw portion at concentrations (0.1-7% by weight) sufficient to maintain pH control only at the interface where water contact occurs. The bulk of the low Aw portion maintains its original pH and flavor characteristics, while only the interface region experiences pH reduction. This localized pH control resolves the contradiction by restricting the harmful pH change to only where it is needed for microbial prevention.
Solution Approach 2:
The patent specifies precise GDL concentration ranges (0.1 to 7% by weight of the second portion) to optimize the balance between pH control effectiveness and flavor preservation. By controlling the parameter of GDL concentration, the system achieves sufficient interface pH reduction for microbial inhibition while minimizing impact on the overall flavor profile of the low Aw portion.
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
This approach extends the shelf life of the composition by maintaining a lower pH at the interface, thereby reducing the risk of microbial growth and improving the effectiveness of antimicrobial compounds.
Implementation Method 1
GDL included in the second portion in an amount sufficiently distributed throughout the second portion to provide an interface pH that is lower than the second pH
Data Source
AI summary
Compositions are described that use glucono delta lactone (GDL) in a portion of a composition containing two portions with differing water activities. GDL is included in a low water activity portion that is in contact with a high water activity portion, such that an interface formed between the two portions contains gluconic acid formed by contact of GDL with water from the high water activity portion. Methods of controlling pH in a composition containing two portions with differing water activities and methods of controlling microbial growth at an interface of two portions with differing water activities are also described.