Toggle Main Menu Toggle Search

Open Access padlockePrints

Milk: Light Exposure and Depletion of Key Nutrients

Lookup NU author(s): Dr Cath BirchORCiD, Professor Graham BonwickORCiD

Downloads


Licence

This is the final published version of a report published in its final definitive form in 2019. For re-use rights please refer to the publishers terms and conditions.


Abstract

The most recent scientific evidence supports the consumption of cow’s milk across the age spectrum as part of a healthy diet. Fresh milk contributes essential macro- and micronutrients including protein, calcium and vitamins A, B and D to the diet, that aids growth during rapid development in early childhood. Scientific studies have demonstrated extensively that exposure of milk to light from any source has negative effects, such as loss of vitamins and protein degradation. In dairy products, especially milk, compelling evidence has been presented that exposure to light of a range of wavelengths is responsible for a significant loss of essential micronutrients required for human development and health. Recent studies have shown that exposure of milk to light from any source causes a loss of vitamins such as riboflavin (vitamin B2). Other effects on the nutritional properties of milk have included changes in levels of retinol (vitamin A); ergocalciferol (vitamin D2); cholecalciferol (vitamin D3); cobalamin (vitamin B12); pyridoxine (vitamin B6); ascorbic acid (vitamin C) and protein. Consumer studies consistently show that purchasers of milk can detect off-flavours within a short period of time. This effect has been linked to exposure of light at visible wavelengths under λ500nm, which induces the strongest formation of the negative ‘sunlight flavour’ in milk. However, blocking these wavelengths of light does not always reduce the detrimental off-flavours. It is recommended that retailers of milk should take measures that minimise the detrimental effects of light. The high-intensity light sources currently used in retail milk displays that includes fluorescence and LED lighting systems utilise wavelengths that are detrimental to nutrients in fluid milk. Use of packaging material with light-barrier capability is one of the best solutions to protect milk from damaging photooxidation processes. However, manufacturers of packaging should use materials that are certified for light protection to ensure that consumers are receiving the full nutritional value of milk.


Publication metadata

Author(s): Birch CS, Bonwick GA

Publication type: Report

Publication status: Published

Series Title:

Year: 2019

Online publication date: 23/05/2019

Acceptance date: 10/05/2019

URL: https://www.lightdamageisreal.co.uk/wp-content/uploads/2019/05/milk-light-exposure-and-depletion-of-key-nutrients.pdf


Share