First Generation of Controlled-Release Bacteriocins/Anti-Microbials

Combat ration Intermediate Moisture (IM) products use low pH and water content (aw) to discourage bacterial growth. The long-term goal of this proposal is to maintain the microbial stability of ration components over a two-year shelf life while increasing the pH and aw values for an improved organoleptic profile. The specific objective of this Phase I application is to develop microspheres for continuous, controlled-release of Nisaplin over a two-year period using Orbis"Precision Particle Fabrication (PPF) microsphere encapsulation technology. The incorporation of this time-released system in addition to a one-time injection during initial packaging would allow for higher pH and aw thresholds, providing a safe, high-quality ration platform with improved palatability. First, uniform, Nisaplin-loaded microspheres with three different diameters will be formulated to characterize in vitro release kinetics. Second, through in vitro release testing, the formulation of Nisaplin-loaded microspheres will be optimized to achieve sustained, two-year Nisaplin release. In the Phase I Option, the controlled-release system will be compared to single-dose delivery. The central hypothesis is that uniform, Nisaplin-loaded PPF microspheres will offer a cost- and dose-effective food preservation system with precisely tailored anti-microbial release characteristics to effectively inhibit gram-positive pathogens over the two year shelf-life of the food product.