Food Engineering / Gıda Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/12

Browse

Search Results

Now showing 1 - 2 of 2
  • Article
    Citation - WoS: 14
    Citation - Scopus: 17
    Phenolics Profile of a Naturally Debittering Olive in Comparison To Regular Olive Varieties
    (John Wiley and Sons Inc., 2014) Aktaş, Ayşe Burcu; Özen, Banu; Tokatlı, Figen; Şen, İlknur
    BACKGROUND: Hurma, an olive variety that grows in a specific area in Turkey, loses its bitterness before harvesting, and therefore does not need further processing steps for the production of table olives. The total phenol content and phenolic profiles of (1) this naturally debittered olive type, Hurma; (2) the same olive variety, but not a naturally debittered type, Erkence; and (3) another variety, Gemlik, which is commonly consumed as table olive, were determined during their maturation period for two harvest years. RESULTS: The total phenol content of Hurma is the lowest compared to the other types regardless of harvest year, which has a significant effect on the phenolic content and composition of individual components for all olive types. All three olive types can be differentiated from each other especially during the late phase of maturation using the phenolics profile in combination with principal component analysis. CONCLUSION: The natural debittering phenomenon of Hurma olive on the tree involves a decrease in phenol content and a change in phenol composition. The differentiation in phenol composition especially becomes very significant in the late of period of maturation.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 23
    Water-Soluble Antioxidant Potential of Turkish Pepper Cultivars
    (American Society for Horticultural Science, 2008) Frary, Anne; Keçeli, Mehmet Ali; Ökmen, Bilal; Şığva, Hasan Özgür; Yemenicioğlu, Ahmet; Doğanlar, Sami
    In this work, 29 pepper cultivars that represent the diversity of types and varieties grown in Turkey were analyzed for water-soluble antioxidant capacity and phenolic and vitamin C contents. In addition, 14 non-Turkish cultivars were tested for comparison. Significant diversity was observed in the different cultivars with the most variation (7.4-fold) seen for total antioxidant capacity, which ranged from 2.57 to 18.96 mmol Trolox/kg. Vitamin C content for the peppers ranged from 522 to 1631 mg·kg-1, a 3.1-fold difference, whereas total phenolic content for the pepper cultivars ranged from 607 to 2724 mg·kg-1, a 4.5-fold difference. When cultivars were grouped by morphology/ use, it was found that some types had significantly more variation and higher antioxidant activities than other types. Thus, for water-soluble antioxidant capacity, most variation was seen in long, blunt-ended Çarliston types, whereas long, pointed Sivri peppers had the highest mean capacity. Bell-shaped Dolmalik and Sivri peppers had the most variation for phenolic content, but fancy Süs and Sivri types had the highest means for this trait. Dolmalik types showed the most variation for vitamin C content, whereas Süs and Sivri peppers had the highest means for this character. All three parameters were significantly and positively correlated with the strongest correlation between total antioxidant capacity and phenolic content (r = 0.71). The presence of significant variation for antioxidant content in Turkish germplasm indicates that this material can be used for improvement and genetic mapping of nutritional content in pepper.