Fraunhofer Institute for Process Engineering and Packaging IVV
Food storage conditions
Impact on the best-by-date
How storage conditions impact food shelf life
Storage conditions directly dictate the shelf life of food products. Oxygen levels, ambient humidity, and light exposure play a particularly decisive role in determining product stability.
We run controlled storage tests and deliver reliable shelf life predictions across custom scenarios to help you maximize product quality and shelf life. By analyzing this data, we pinpoint the ideal storage environments and packaging solutions tailored to your specific product. Leveraging our deep materials expertise, we also project shelf life outcomes for innovative packaging concepts.
Oxygen – Nutrient degradation and off-flavor formation
During storage, oxygen reacts with unsaturated fatty acids, triggering radical autoxidation. This process initially generates lipid hydroperoxides, which break down into volatile organic compounds like hexanal, propanal, and butanal – the key culprits behind rancid odors and off-flavors. Concurrently, sensitive compounds such as vitamins and pigments can undergo oxidative degradation. Light and trace metal ions like iron or copper act as catalysts, significantly accelerating this reaction cascade. Antioxidants – including natural polyphenols, tocopherols, and carotenoids – scavenge free radicals and neutralize reactive oxygen species, noticeably slowing or delaying oxidation.
Oxygen protection – Actionable steps
In practice, strict protection against oxygen and light, avoiding metal food-contact surfaces, and preserving or intentionally adding suitable antioxidants all help retain flavor and valuable nutrients.
Humidity: A key factor in shelf life
As relative humidity rises, food quality declines and spoilage accelerates. While many products remain stable below 50% relative humidity, stability drops significantly above this threshold. Higher moisture levels trigger texture changes, accelerate chemical reactions (such as Maillard browning and lipid oxidation), boost enzymatic activity, and promote microbial growth.
Humidity protection – Actionable steps
Dry storage conditions and high water-vapor barrier packaging significantly extend food shelf life.
Light – A driver of color and flavor degradation
Both UV and visible light supply activation energy for chemical reactions. The results include accelerated lipid oxidation, discoloration, nutrient loss, and off-flavor formation during food storage. In fact, just a few minutes of light exposure can cause noticeable shifts in color and taste. The reaction of riboflavin (vitamin B2) is a prime example: yellow riboflavin absorbs blue light and transfers this energy to oxygen molecules, dramatically speeding up lipid oxidation. In the absence of oxygen, the absorbed energy splits the riboflavin molecule itself, leading to discoloration and a distinct cardboard-like off-flavor.
Light protection – actionable steps
Lightproof packaging provides complete protection against light-induced degradation. Amber packaging (such as amber glass bottles) also offers high-level protection by absorbing sensitive blue wavelengths and shielding the product effectively.
FAQ – Food storage conditions
Why don't UV filters in packaging always provide enough protection against food spoilage?
While UV filters block high-energy radiation, they cannot prevent all light-induced quality loss. Visible light can also degrade food products. Natural photosensitizers (such as chlorophyll or riboflavin) absorb visible light and transfer that energy to available oxygen, creating highly reactive singlet oxygen that turns fats rancid.
Even in the absence of oxygen, light-driven reactions still occur. Without oxygen present, the photosensitizers themselves break down, leading to noticeable color and flavor changes.
Why is precise determination of food light sensitivity essential for packaging development?
Knowing product light sensitivity is critical because even tinted packaging materials or sleeves can remain permeable to harmful wavelengths. Fraunhofer IVV evaluates this sensitivity on a product-specific basis under realistic lighting conditions (such as retail point-of-sale lighting). This analysis enables tailored packaging design that maximizes shelf life while avoiding the costs of over- or under-packaging.
Why is determining oxygen sensitivity decisive for food shelf life?
Understanding oxygen sensitivity forms the foundation for exact barrier requirements. Using specialized testing methods, Fraunhofer IVV measures product-specific oxygen uptake under relevant storage conditions. From this data, we derive critical oxygen limits and predict total shelf life – delivering optimal protection against rancidity while eliminating unnecessary over-packaging.
How do accelerated storage tests work for shelf life determination?
Accelerated shelf-life testing relies on the Q10 rule (Reaction Rate-Temperature Rule): a 10 °C (18 °F) increase in temperature roughly doubles the rate of chemical reactions. This allows long-term degradation processes to be simulated in fast-forward, significantly shortening testing timelines and providing early, reliable insights into product stability and shelf life.