High- but not low-intensity light leads to oxidative stress and quality loss of cold-stored baby leaf spinach

• Published in: Journal of the science of food and agriculture 2015-07, Vol.95 (9), p.1821-1829
• Main Authors: Glowacz, Marcin, Mogren, Lars M, Reade, John PH, Cobb, Andrew H, Monaghan, James M
• Format: Article
• Language: English
• Subjects: ascorbic acid; Ascorbic Acid - analysis; Carotenoids - analysis; Cell Membrane - chemistry; Cell Membrane - radiation effects; Cell Membrane Permeability - radiation effects; Chemical Phenomena; Cold storage; colour evaluation; Damage; Dose-Response Relationship, Radiation; England; Experiments; Exposure; Flavonoids - isolation & purification; Food Packaging; Food Quality; Food Storage; Foods; Humans; Light - adverse effects; light intensity; Maintenance; membrane integrity; Nutritive Value; Oxidative stress; Oxidative Stress - radiation effects; Perishable goods; Pigments, Biological - analysis; Plant Leaves - chemistry; Plant Leaves - growth & development; Plant Leaves - radiation effects; Quality management; Refrigeration; shelf-life; Spinach; Spinacia oleracea; Spinacia oleracea - chemistry; Spinacia oleracea - growth & development; Spinacia oleracea - radiation effects; Stresses; Surface layer; Texture; Vegetables; Water - analysis
• ISSN: 0022-5142; 1097-0010
• DOI: 10.1002/jsfa.6880

BACKGROUND Quality management in the fresh produce industry is an important issue. Spinach is exposed to various adverse conditions (temperature, light, etc.) within the supply chain. The present experiments were conducted to investigate the effect of light conditions (dark, low‐intensity light (LL) and high‐intensity light (HL)) and photoperiod (6 h HL and 18 h dark) on the quality changes of cold‐stored spinach. RESULTS HL exposure resulted in oxidative stress, causing tissue damage and quality loss as evidenced by increased membrane damage and water loss. The content of total ascorbic acid was reduced under HL conditions. On the other hand, storage of spinach under LL conditions gave promising results, as nutritional quality was not reduced, while texture maintenance was improved. No significant differences, with the exception of nutritional quality, were found between spinach leaves stored under continuous (24 h) low‐intensity light (30–35 µmol m−2 s−1) and their counterparts stored under the same light integral over 6 h (130–140 µmol m−2 s−1). CONCLUSION LL extended the shelf‐life of spinach. The amount of light received by the leaves was the key factor affecting produce quality. Light intensity, however, has to be low enough not to cause excess oxidative stress and lead to accelerated senescence. © 2014 Society of Chemical Industry