iltning

Iltning is the process in which a substance reacts with oxygen from the air, resulting in chemical changes that can alter color, texture, flavor, or structural integrity. The term is used in several Scandinavian languages to describe oxidation in contexts such as foods, metals, and polymers.

There are different pathways for iltning. Autoxidation occurs when reactive radicals are formed from the substance itself and propagate chain reactions with oxygen. Enzymatic iltning involves enzymes that catalyze oxidation, such as polyphenol oxidase in fruits and vegetables. In metals, iltning refers to corrosion processes where metal surfaces react with oxygen and moisture to form oxide layers, which can either protect or weaken the material depending on conditions.

Common examples illustrate its impact. In food, iltning can lead to rancidity of fats and oils, browning of cut fruits, or spoilage of fats through lipid oxidation. In metals, iron can rust when exposed to oxygen and water, changing mechanical properties and appearance. In polymers, oxidation can cause discoloration, embrittlement, and loss of elasticity over time.

Prevention and control focus on reducing oxygen exposure, limiting light and heat, and slowing catalytic reactions. Strategies include using antioxidants, proper packaging (airtight, low-oxygen environments, or inert atmospheres), storing at cool temperatures, and protecting materials with coatings or stabilizers. In foods, handling practices and packaging design aim to maintain quality and extend shelf life; in metals and polymers, stabilizers and protective layers can delay deterioration.

Measurement and monitoring of iltning rely on sensory analysis (appearance and odor) and chemical tests that quantify oxidation products, such as peroxide values or other indicators of oxidative stress. These tools help assess shelf life, safety, and material performance in industrial and consumer contexts.