title: Quality evaluation of cook-chilled chicory stems (Cichorium intybus L., Catalogna group) by conventional and sous vide cooking methods.
abstract: BACKGROUND
  Chicory stems, appreciated both raw and cooked, represent a nutritious and refined food. In this study the effects on the quality of stems cooked by conventional (boiling, steaming and microwaving) and innovative (sous vide) methods were analysed. Several physical, chemical and sensory traits were compared using two local varieties (Galatina and Molfettese) of southern Italy (Puglia region).
  
  
  RESULTS
  Independently of the variety, the sous vide method did not significantly affect (redness, yellowness and hue angle) or had the least impact on (lightness and total colour difference) quality parameters among the four methods as compared with the raw product. Following sensory analysis, the sous vide product always showed the highest score among the cooking methods. Moreover, this innovative method did not affect total phenol (TP) content and antioxidant activity (AA) compared with uncooked stems of both varieties. Microwaving increased TP content and AA (though associated with higher weight loss), while different responses depending on the chicory variety were observed after boiling and steaming.
  
  
  CONCLUSIONS
  The results indicate the sous vide technique as optimal to preserve several traits, including organoleptic ones, for the quality of cook-chilled chicory stems. They also provide product-specific information usually required for cooking process strategies in the industrial sector of ready-to-eat vegetables.
authors.affiliation: Institute of Sciences of Food Production, CNR-National Research Council of Italy, Via G. Amendola 122/O, I-70126, Bari, Italy.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Renna
authors.forename: Maria
authors.initials: M
authors.lastname: Gonnella
authors.forename: Donato
authors.initials: D
authors.lastname: Giannino
authors.forename: Pietro
authors.initials: P
authors.lastname: Santamaria
mesh_terms: D000975:Antioxidants / Q000032:analysis; D055598:Chemical Phenomena; D018651:Cichorium intybus / Q000737:chemistry* / Q000254:growth & development / Q000528:radiation effects; D003258:Consumer Behavior; D003296:Cooking / Q000379:methods*; D057140:Fast Foods / Q000032:analysis*; D005260:Female; D005518:Food Preferences; D063427:Food Quality; D006801:Humans; D007558:Italy; D008297:Male; D008872:Microwaves / Q000009:adverse effects; D010860:Pigments, Biological / Q000032:analysis; D018547:Plant Stems / Q000737:chemistry* / Q000254:growth & development / Q000528:radiation effects; D025341:Principal Component Analysis; D012034:Refrigeration / Q000009:adverse effects; D012677:Sensation; D013227:Steam / Q000009:adverse effects; D014675:Vegetables / Q000737:chemistry / Q000254:growth & development / Q000528:radiation effects
chemical_list: D000975:Antioxidants; D010860:Pigments, Biological; D013227:Steam
keywords: antioxidant activity; local varieties; nitrate content; sensory evaluation; total phenols