Improving the shelf life of food with minimal chemical preservatives can be achieved through a variety of natural and technological methods. Here are several strategies:

Natural Preservatives
1. Antioxidants: Natural antioxidants such as vitamin E, vitamin C, and certain plant extracts (like rosemary) can help slow down oxidation, which is a major cause of food spoilage.
2. Antimicrobial Agents: Natural antimicrobials like garlic, ginger, clove, and oregano oils can inhibit the growth of bacteria, yeast, and mold.
3. Salt and Sugar: Both act as natural preservatives by drawing out moisture and creating an environment less favorable to microbial growth.
4. Fermentation: This process naturally produces beneficial bacteria that can outcompete harmful bacteria, thus preserving the food.
5. Vinegar: The acetic acid in vinegar has antimicrobial properties that help preserve foods.

Physical Methods
1. Refrigeration and Freezing: Lowering the temperature slows down the growth of microorganisms and the rate of spoilage.
2. Dehydration: Removing water from food (through drying or freeze-drying) inhibits microbial growth.
3. Vacuum Packing: Removing air from packaging reduces the oxygen available to spoilage organisms.
4. Modified Atmosphere Packaging (MAP): Altering the composition of the gas inside the packaging (often replacing oxygen with nitrogen or carbon dioxide) can extend shelf life.
5. High-Pressure Processing (HPP): This method uses high pressure to inactivate pathogens and spoilage organisms without the need for heat or chemicals.

Storage Conditions
1. Proper Storage: Ensuring food is stored at the appropriate temperature and humidity levels can significantly extend shelf life.
2. Clean Environment: Maintaining cleanliness and sanitation in storage areas reduces the risk of contamination.
3. Controlled Atmosphere Storage: Similar to MAP, this involves controlling the atmospheric conditions (like oxygen, carbon dioxide, and ethylene levels) in the storage environment.

Innovative Technologies
1. Edible Coatings: Applying thin, edible films made from natural substances like chitosan, alginate, or beeswax can protect food from oxygen and moisture.
2. Biopreservation: Using beneficial bacteria or their metabolites to inhibit the growth of spoilage organisms and pathogens.
3. Ultraviolet (UV) Light: UV-C light can be used to disinfect the surface of foods, reducing microbial load.
4. Pulse Electric Fields (PEF): This technology uses short bursts of high voltage to kill microorganisms without significant heating.

By combining these natural, physical, and technological methods, it is possible to extend the shelf life of food products with minimal reliance on chemical preservatives.