Texture, composition and anatomy of spinach leaves in relation to nitrogen fertilization.
J Sci Food Agric
; 93(2): 227-37, 2013 Jan.
Article
em En
| MEDLINE
| ID: mdl-22806403
ABSTRACT
BACKGROUND:
The postharvest quality and shelf life of spinach are greatly influenced by cultural practices. Reduced spinach shelf life is a common quandary in the Salinas Valley, California, where current agronomic practices depend on high nitrogen (N) rates. This study aimed to describe the postharvest fracture properties of spinach leaves in relation to N fertilization, leaf age and spinach cultivar.RESULTS:
Force-displacement curves, generated by a puncture test, showed a negative correlation between N fertilization and the toughness, stiffness and strength of spinach leaves (P > 0.05). Younger leaves (leaves 12 and 16) from all N treatments were tougher than older leaves (leaves 6 and 8) (P > 0.05). Leaves from the 50 and 75 ppm total N treatments irrespective of spinach cultivar had higher fracture properties and nutritional quality than leaves from other N treatments (P > 0.05). Total alcohol-insoluble residues (AIR) and pectins were present at higher concentrations in low-N grown plants. These plants also had smaller cells and intercellular spaces than high-N grown leaves (P > 0.05).CONCLUSION:
Observed changes in physicochemical and mechanical properties of spinach leaves due to excess nitrogen fertilization were significantly associated with greater postharvest leaf fragility and lower nutritional quality.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Qualidade dos Alimentos
/
Spinacia oleracea
/
Folhas de Planta
/
Fertilizantes
/
Ciclo do Nitrogênio
Limite:
Humans
País/Região como assunto:
America do norte
Idioma:
En
Revista:
J Sci Food Agric
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos