Fruit vitamin C content of 40 cultivars and its changes after four basic cooking procedures- steaming, boiling, pie making, and jam making were measured. Cultivars varied in their vitamin C content from 200 to 600 mg/100 g fresh weight. During the fruit maturation process, the green/cream stage fruit had higher vitamin C content than fully matured fruit (80-100% red/brown color). If customers are concerned about jujube’s health benefit, a cultivar’s vitamin C content should be considered as well as other fruit quality characteristics. The small fruit of sour jujube (Ziziphus spinosa) is without much flesh for fresh eating, but has higher vitamin C content than cultivated cultivars (Z. jujuba) and could be used for processing healthy drinks or food. After steaming or boiling, over 80% of vitamin C was preserved in the fruit. When fruit were used for jam, the final product retained over 80% of the vitamin C content of the fresh fruit. Jujube pie only preserved 45-50% of its original vitamin C content. Compared with reports of over 90% vitamin C loss during the sun-drying process, fresh processed products preserve vitamin C well.
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Prijevod:
Izmjeren je sadržaj vitamina C u plodu 40 sorti i njegove promjene nakon četiri osnovna postupka kuhanja- kuhanja na pari, ključanja, pravljenja pita i pekmeza. Sadržaj vitamina C kultivara varirao je od 200 do 600 mg/100 g svježe mase. Tijekom sazrijevanja voća, zeleno/kremasto voće imalo je veći sadržaj vitamina C od potpuno sazrelog voća (80-100% crvene/smeđe boje). Ako su kupci zabrinuti zbog zdravstvene koristi žižule, treba uzeti u obzir sadržaj vitamina C sorte, kao i druge karakteristike kvalitete voća. Mali plod kisele žižule (Ziziphus spinosa) nema puno mesa za svježu prehranu, ali ima veći sadržaj vitamina C od uzgojenih sorti (Z. jujuba) i mogao bi se koristiti za preradu zdravih napitaka ili hrane. Nakon kuhanja na pari ili kuhanja, u plodu je sačuvano preko 80% vitamina C. Kad se voće koristilo za pekmez, konačni proizvod zadržao je više od 80% sadržaja vitamina C u svježem voću. Pita od žižule sačuvala je samo 45-50% izvornog sadržaja vitamina C. U usporedbi s izvješćima o preko 90% gubitka vitamina C tijekom procesa sušenja, svježi prerađeni proizvodi dobro čuvaju vitamin C.