Seyed Yousef Pourmir; Alireza Sadeghi Mahoonak; Javad Fattahi Moghadam; Yahya Maghsoudlou; Mohammad Ghorbani
Abstract
Introduction: Citrus fruits, which belong to the family of rutaceae are one of the main fruit tree crops grown throughout the world. Although sweet orange (Citrus sinensis) is the major fruit in this group accounting for about 70% of citrus output.Citrus fruits are well – appreciated fortheir refreshing ...
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Introduction: Citrus fruits, which belong to the family of rutaceae are one of the main fruit tree crops grown throughout the world. Although sweet orange (Citrus sinensis) is the major fruit in this group accounting for about 70% of citrus output.Citrus fruits are well – appreciated fortheir refreshing juice and health benefits.The health benefits of citrus fruits are linked to the high amounts of photochemical and bioactive compoundssuch as flavonoids, carotenoids, vitamins and minerals available in their juice.These phytonutrientsmay act as antioxidants, stimulate the immune systems; induce protective enzymes in theliver or blockthe damage of the genetic materials. The phytonutrients and vitamins may be responsible for theantioxidant, anticancer and anti-inflammatory properties of the citrus species.Citrus fruits processing accounts for approximately one third of total citrus fruitproduction, more than 80% of it is orange processing, mostly for orange juice production.The most important processed citrus fruits product isorange juice. Orange juice can be presented in different forms. The major types of orangejuice are the freshly squeezed orange juice and concentrated orange juice.Siavaraz local orange is an orange cultivar grown in north of Iran which is used mainly in orange juice production. There is no systematic study about the relation between physical characteristic of fruit at harvest time and its juice quality and quantity. Materials and methods:In this study, the physical characteristics, quantitative-qualitive properties of siavaraz local orange at harvesting times and changes in anti-oxidant components of its juice during processing and storage were investigated.The fruit were collected in eleven different harvest time (start of fruit harvesting and every two week intervals) and different parameters including fruit length, diameter, spherical coefficient, density, peel thickness, juice percentage, total soluble solid (TSS),titrable acidity(TA) were evaluated. In next stage ascorbic acid, total phenolics and anti-oxidant capacity of different fruit juice include fresh squeezed juice by hand and extractor, juice reconstituted from orange concentrate with 60° brix, juice reconstituted from orange concentrate with 65° brixwere evaluated and compared. Finally, changes in vitamin C content during refrigerated storage infresh squeezed juice by hand andjuice reconstituted from orange concentrate were measured. Results & Discussion:Results showed that siavaraz local orange was in four size with different physical characteristics. The highest amount of density was belonged to small fruits with 0.977 at the first harvest stage. Small oranges with lowest peel thickness had the highest juice percentage but the large oranges with the higher TSS showedhigher production efficiency (327.24%). The TA and pH in first stage of harvest were the highest and the lowest, respectively compared to other stage. The highest concentrate efficiency (6.42%) and juice quality (9.88° brix) were obtained at the harvest stagenumber six and seven, respectively. The lowest amount of juice percentage for concentrate production was observed at the stagenumber six (15.6 kg). By investigating the anti-oxidant compounds, results reveals that ascorbic acid and anti-oxidant capacity of juice taken by juicer extractor, were higher (p
Mohammad Farhadi Chitgar; Mohammad Javad Varidi; Mehdi Varidi; Fakhri Shahidi
Abstract
Barberry is an agricultural product, which is cultivated in large amounts, only in Iran. Its popularity as an ingredient for many by-products has grown recently. It contains anthocyanins which can be used as natural food colorants. These compounds are useful for human health and have high economic value. ...
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Barberry is an agricultural product, which is cultivated in large amounts, only in Iran. Its popularity as an ingredient for many by-products has grown recently. It contains anthocyanins which can be used as natural food colorants. These compounds are useful for human health and have high economic value. Magnitude and duration of heating has a strong influence on anthocyanin stability. Temperature degrades the anthocyanins and the rates of degradation depend on the presence of oxygen, pH and their chemical structure. In this study the effect of temperature and solid content on degradation kinetic of anthocyanins in Berberis vulgaris var asperma were determined over a temperature range of 70-90◦C. Analysis of kinetic data suggested a first-order reaction for the degradation of barberry juice and concentrate anthocyanins. The half-life values were calculated 6.02, 3.32 and 1.06h for juice, 3.32, 1.84 and 0.76h for concentrate of 30 Brix and 3.19, 1.31 and 0.49h for concentrate of 50 Brix between 70 and 90◦C, respectively.The temperature-dependent degradation was modeled using Arrhenius equation. By increasing solid content, the activation energy value was increased but D-value and Z-values were reduced. The results shows that the degradation of anthocyanins in concentrates occurred at a faster rate than in juice. By increasing the temperature degradation rates were increased both in juice and concentate.
