title: Influence of acidification, pasteurization, centrifugation and storage time and temperature on watermelon juice quality.
abstract: BACKGROUND
  Watermelon juice has gained increasing popularity among consumers as a rich natural source of functional compounds such as lycopene and citrulline. However, the final quality of the juice depends significantly on its acidification, pasteurization, centrifugation and storage time and temperature. In this study, these characteristics were assessed in watermelon juice pasteurized at 87.7 °C for 20 s and stored for up to 30 days at 4 or 8 °C.
  
  
  RESULTS
  The acidifier citric acid provided an adequate sensory quality, similar to natural watermelon juice. Centrifugation and pasteurization significantly reduced the red color, bioactive compounds (lycopene, antioxidant capacity and total polyphenols) and sensory quality of the juice, particularly when the storage time was extended and a temperature of 8 °C was used (P ≤ 0.05). All treated juices were microbiologically safe for up to 30 days when stored at 4 or 8 °C. In terms of sensory acceptability, only non-centrifuged juices stored for up to 20 days at 4 °C remained above the commercial limit.
  
  
  CONCLUSIONS
  The present results suggest that using a non-centrifugation process and a storage temperature of 4 °C yields a watermelon juice that better retains its sensory and functional qualities.
authors.affiliation: Postharvest and Refrigeration Group, Department of Food Engineering, Universidad Politécnica de Cartagena, Paseo Alfonso XIII, 48, E-30203, Cartagena, Murcia, Spain; Institute of Plant Biotechnology, Universidad Politécnica de Cartagena, Plaza del Hospital s/n, Campus Muralla del Mar, E-30202, Cartagena, Murcia, Spain.
authors.forename: Martha Patricia
authors.initials: MP
authors.lastname: Tarazona-Díaz
authors.forename: Encarna
authors.initials: E
authors.lastname: Aguayo
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001628:Beverages / Q000032:analysis / Q000592:standards; D002338:Carotenoids / Q000032:analysis*; D002498:Centrifugation; D019343:Citric Acid; D029773:Citrullus / Q000737:chemistry*; D003116:Color; D004032:Diet; D005260:Female; D005511:Food Handling / Q000379:methods*; D005638:Fruit / Q000737:chemistry*; D006801:Humans; D000077276:Lycopene; D008297:Male; D061352:Pasteurization; D028321:Plant Preparations / Q000737:chemistry / Q000592:standards; D059808:Polyphenols / Q000032:analysis*; D013696:Temperature
chemical_list: D000975:Antioxidants; D028321:Plant Preparations; D059808:Polyphenols; D019343:Citric Acid; D002338:Carotenoids; D000077276:Lycopene
keywords: Citrullus lanatus; beverage; bioactive compounds; lycopene; total antioxidant capacity