Chlorophyll and colour changes in grapevine leaves preserved by passive modification

Kirca A., YEMIS O., OZKAN M.

EUROPEAN FOOD RESEARCH AND TECHNOLOGY, vol.223, no.3, pp.387-393, 2006 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 223 Issue: 3
  • Publication Date: 2006
  • Doi Number: 10.1007/s00217-005-0216-6
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.387-393
  • Keywords: grapevine leaves, chlorophyll-a, chlorophyll-b, -a*/b*, microbial quality, DEGRADATION KINETICS, SPINACH LEAVES, GREEN COLOR, QUALITY, PEAS, STABILITY
  • Çanakkale Onsekiz Mart University Affiliated: Yes


Grapevine leaves are used to prepare the dish called as "dolma," i.e., a Turkish term for stuffed vegetable. Our study was undertaken to monitor the desirable colour changes from bright-green to olive-yellow in grapevine leaves stored under modified atmosphere (passive modification). We also determined whether microbial growth occurred after a prolonged storage (9 mo) at 20 degrees C. For this purpose, grapevine leaves from two common varieties grown in Turkey were placed in hermetically-sealed glass jars and stored at 20 degrees C for 9 mo. Since the colour is the most important quality criteria for grapevine leaves, the changes in chlorophyll-a and chlorophyll-b, and colour variables were monitored during storage. Chlorophyll-a and -b were identified and quantified by HPLC. Chlorophyll-b was more stable than chlorophyll-a in both varieties studied. Compared to varieties, chlorophylls in Narince variety were less stable than those in Sultani variety. Since consumers expect olive-yellow colour in grapevine leaves, Narince variety is more suitable for this technique. Excellent correlation was found between -a(*)b(*)colour variable and chlorophyll-a concentration (r=0.9829-0.9832). Mesophilic bacteria were found to be low level (3.2x10(1) cfu/g), whereas yeast and molds, lactic acid bacteria and Enterobacteriaceae were below the lowest detection limit (< 10 cfu/g) in the leaves stored at 20 degrees C for 9 mo. The results suggest that passive modification is very effective to achieve the desirable colour transformation of grapevine leaves in a very short period of time (2-6 days) depending on the variety. Moreover, this simple technique gives rise to a product with good microbial quality.