Yazar "Erge, Hande Selen" seçeneğine göre listele
Listeleniyor 1 - 14 / 14
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe BEYAZ, YEŞİL VE SİYAH ÇAYLARIN (CAMELLIA SINENSIS) BAZI FİZİKSEL VE KİMYASAL ÖZELLİKLERİNİN BELİRLENMESİ(2017) Atalay, Derya; Erge, Hande SelenÇay; her zaman yeflil olan, yağmurlu ve ılık iklimleri seven Theaceae familyasında bulunan bir bitkidir.Dünya'da en yaygın tüketilen içeceklerden biri olan çay, sağlık üzerine pozitif etkisinin yanında lezzetve aromasından dolayı ilgi çekmektedir. Çay; fermente olmayan (yeflil ve beyaz), kısmen fermente olan(oolong) ve fermantasyona uğrayan çay (siyah) olmak üzere 3 gruba ayrılmaktadır. Bu çalıflmadakiamaç; beyaz, yeflil ve siyah çayda su aktivitesi ve renk gibi fiziksel; kül, toplam fenolik, toplam flavonoidmadde miktarı, antioksidan aktivite ile kafein ve bazı fenolik bileflik içeriği gibi kimyasal özelliklerinbelirlenmesidir. Yeflil çay, beyaz ve siyah çaya göre biyoaktif bileflenler açısından ön plana çıkmaktadır.Bunun sebebi ise yeflil çay üretiminde kıvrılan yapraklara buhar uygulaması nedeniyle fenolik bilefliklerinokside olmaması fleklinde açıklanmaktadırÖğe Beyaz, yeşil ve siyah çayların (camellia sinensis) bazı fiziksel ve kimyasal özelliklerinin belirlenmesi(2017) Atalay, Derya; Erge, Hande SelenÇay; her zaman yeflil olan, yağmurlu ve ılık iklimleri seven Theaceae familyasında bulunan bir bitkidir.Dünya'da en yaygın tüketilen içeceklerden biri olan çay, sağlık üzerine pozitif etkisinin yanında lezzetve aromasından dolayı ilgi çekmektedir. Çay; fermente olmayan (yeflil ve beyaz), kısmen fermente olan(oolong) ve fermantasyona uğrayan çay (siyah) olmak üzere 3 gruba ayrılmaktadır. Bu çalıflmadakiamaç; beyaz, yeflil ve siyah çayda su aktivitesi ve renk gibi fiziksel; kül, toplam fenolik, toplam flavonoidmadde miktarı, antioksidan aktivite ile kafein ve bazı fenolik bileflik içeriği gibi kimyasal özelliklerinbelirlenmesidir. Yeflil çay, beyaz ve siyah çaya göre biyoaktif bileflenler açısından ön plana çıkmaktadır.Bunun sebebi ise yeflil çay üretiminde kıvrılan yapraklara buhar uygulaması nedeniyle fenolik bilefliklerinokside olmaması fleklinde açıklanmaktadırÖğe Color stability and change in bioactive compounds of red beet juice concentrate stored at different temperatures(Springer India, 2019) Kayın, Nilay; Atalay, Derya; Akçay, Tuğba Türken; Erge, Hande SelenIn the present study, effect of storage temperature (25 degrees, 35 degrees and 45 degrees C) and light (with/without aluminum foil) on betalain content, color stability and bioactive compounds of concentrated red beet juice were investigated. Degradation of betalains and change in total phenolics content followed first-order kinetics while changes of L*, a*, b* and C* values and antioxidant capacity fitted zero-order kinetic. It was determined that the reaction rate constants of betacyanin and betaxanthin degradations in red beet juice concentrates increased with increasing storage temperature and time. The activation energies for betaxanthin degradation (E-a: 92.04-93.27 kJ mol(-1)) in comparison with the activation energies for betacyanin degradation (E-a: 66.07-66.13 kJ mol(-1)) in all samples demonstrate that susceptibility to temperature of betaxanthin is higher than that of betacyanin. According to L* and a* parameters it can be suggested that color stability in red beet juice concentrate stored with aluminum foil found better than that in the sample without aluminum foil. However, there was no significant difference (p > 0.05) between samples with and without foil as regards changes in total phenolics, betalains and antioxidant capacity. In addition, 25 degrees C can be proposed for providing betalain stability of red beet juice concentrates during storage.Öğe Degradation kinetics of bioactive compounds and change in the antioxidant activity of wild strawberry (fragaria vesca) pulp during heating(Springer, 2013) Özşen, Deniz; Erge, Hande SelenThis study determined the effect of heat treatment on bioactive compounds (total monomeric anthocyanins and total phenolics) and the visual colour of wild strawberry (Fragaria vesca) pulp within the temperature range 60-90 A degrees C. The change in the antioxidant activities of the samples was also evaluated. Total monomeric anthocyanins and total phenolics degraded with increasing temperature and time. First-order kinetic models were determined for those reactions. The activation energies for the degradation of total monomeric anthocyanins and total phenolics were 21.6 and 18.95 kJ mol(-1), respectively. The change in visual colour of wild strawberry pulp was also determined using CIE L*a*b* colour parameters. The change in colour parameters also followed first-order reaction kinetics. Activation energies for the variation of colour parameters were within the range 11.92-63.23 kJ mol(-1). The antioxidant activities of heated wild strawberry pulp increased with increasing temperature and time.Öğe Effect of ultrasound on some chemical and microbiological properties of sour cherry juice by response surface methodology(Sage Publications Ltd, 2017) Türken, Tuğba; Erge, Hande SelenIn this study, it is aimed to determine effect of ultrasonication on some chemical and microbiological properties of sour cherry juice by response surface methodology, since ultrasound is known as an alternative method for thermal food processing. Sour cherry juice was sonicated at varying amplitude levels (50, 75, 100%); moderate temperatures (20, 30, 40?); and treatment times of 2, 6, 10min at a constant frequency of 20kHz. Different ultrasonication amplitudes, temperatures, and times had no significant effect on pH,degrees Bx, and titratable acidity. A significant increase in total monomeric anthocyanins was observed as the amplitude level and temperature increased (p<0.01). An increase in the total phenolics was also obtained as the temperature increased (p<0.05). The effect of amplitude level on antioxidant capacity of sour cherry juice was also found significant (p<0.05). Color parameters (L*, a*, b*, C, h) generally increased by increasing temperature, amplitude level, and treatment time. It was determined that Escherichia coli O157:H7 significantly affected by temperature and treatment time (p<0.05).Öğe The effects of chitosan coating and vacuum packaging on quality of fresh-cut pumpkin slices during storage(Wiley, 2022) Yüksel, Çiğdem; Atalay, Derya; Erge, Hande SelenThe quality of fresh-cut products can be improved by edible coatings and packaging. In this study, fresh-cut pumpkin slices, coated with chitosan and vacuum-packed, were stored at 4 and 10 degrees C for 21 days. The effects of chitosan and vacuum packaging on color, microbiological load, and beta-carotene content of samples were performed during storage. Texture analyses were conducted only on the first and last days of the period. Microbial counts of coated and vacuum-packed samples were restricted as compared to untreated samples. At both storage temperatures, beta-carotene content and a* value of all samples increased while L*, b*, C*, and h degrees values decreased. Changes in beta-carotene and color values (a*, b*, C*, and h degrees) were fitted to zero-order kinetics. The highest textural parameters were determined in coated and vacuum-packed samples. Both coated and vacuum-packed pumpkin slices stored at 4 degrees C can be recommended especially for textural and microbiological quality. Novelty impact statement In this study, coated and vacuum-packed fresh-cut pumpkin slices with potential marketability, have been pointed out. It is noticed that chitosan coating combined with vacuum packaging provides a good preservation for fresh-cut pumpkin slices stored at low temperature. Chitosan can be proposed as an antimicrobial agent due to lower microbiological criteria in chitosan-treated pumpkin slices and vacuum packaging can be suggested a good barrier for keeping the color of the samples stored at low temperature.Öğe Gıda takviyeleri ve sağlık üzerine etkileri(2018) Atalay, Derya; Erge, Hande SelenGıda takviyeleri, bir insanın diyetinde desteklemek üzere kullanılan ve vitaminler, mineraller, amino asitler, bitkiler ya da bitkisel diyet bileşenleri gibi besin ögelerini içeren ürünler olarak tanımlanmaktadır. Gıda takviyelerinin kullanımı başarılı satış stratejileri, reklamlar ve internet nedeniyle yaygındır. Gıda takviyelerinin üretimi tablet ve kapsül üretimleri ile benzerlikler göstermektedir. Üretimdeki başlıca basamaklar; reçete oluşturma, karıştırma, öğütme, granülasyon, kurutma, son karıştırma, tablet yapma, tableti presleme, kaplama ve kapsülleme aşamalarıdır. Gıda takviyelerinin üretiminde meyve ve sebzeler, bitkiler, mikroorganizmalar ve hayvansal kaynaklı hammaddeler kullanılmaktadır. Gıdaların insan sağlığı üzerine faydalı özellikleri (antioksidan, besinsel lif vb.) bilindiğinden dolayı günümüzde gıda takviyelerinin tüketimi artmaktadır. Gıda takviyelerinde en fazla gözlenen sorunlar kontaminasyon, katkı maddeleri, toksisite, yanlış doz ve yanlış etiketlemedir. Son zamanlarda ilaç interaksiyonlarından kaynaklı yan etkilerin yanında söz konusu ürünlerle ilgili zehirlenmeler ülkemizde ve dünyada görülmektedir. Gıda takviyelerinin ilaç olarak değerlendirilmemesi gerektiği ancak doğru şekilde tüketildiğinde insanların sağlığını olumlu yönde etkilediği bilinmektedir.Öğe Kinetics of 5-hydroxymethylfurfural (5-HMF) formation and colour change in date fruit fillings stored at different temperatures(Academic Press Inc Elsevier Science, 2024) Karadeniz, Feryal; Atalay, Derya; Erge, Hande Selen; Kaya, Soner; Isik, Betul; Aslanali, OsmanDate fruit filling is a healthy alternative for the food sector due to its beneficial compounds, dietary fibre, minerals and vitamins. It is also widely used in the baking industry as a filling in pastries and biscuits as a sweetener. In the present study, the stability of date fruit filling, as a function of storage time and temperature, was determined. 5-HMF generation and colour changes were monitored at 25, 35 and 45 degree celsius. Results showed that 5-HMF formation increased linearly with an increase in storage time and temperature and followed a zero-order reaction. L* and hue values decreased linearly and also followed a zero-order reaction. In addition, 5-HMF had a negative correlation with L* (r = 0.832-0.863, p < 0.05) and hue values (r = 0.919-0.953; p < 0.05). No fitting model was found for the changes in other CIE colour parameters. Activation energies of 145.39, 56.64 and 71.05 kJ mol-1 were determined for 5-HMF formation, L* and hue values, respectively. Consequently, date fruit fillings stored at 25 C provided a desired result of 5-HMF formation and colour loss compared to fillings stored at 35 and 45 C.Öğe Kinetics of the changes in bio-active compounds, antioxidant capacity and color of Cornelian cherries dried at different temperatures(Springer, 2019) Demir, Hatice Uslu; Atalay, Derya; Erge, Hande SelenThe aim of this research was to determine the effects of oven-drying on degradation of bioactive compounds of Cornelian cherry including total monomeric anthocyanins, total phenolics, total flavonoids and L-ascorbic acid. Changes in antioxidant capacity, percent polymeric color and visual color were also used as quality indicators of Cornelian cherry dried at 50 degrees, 60 degrees and 70 degrees C for 36, 13.5 and 6 h, respectively. A zero-order kinetic model was obeyed for polymeric color formation. First-order reaction kinetics was found for the degradations of monomeric anthocyanins and L-ascorbic acid, while losses in total phenolics, total flavonoids and antioxidant capacity followed second-order kinetic model. The changes in color parameters also obeyed first-order kinetics. The activation energy for the degradations of bioactive compounds was observed in the range of 48.2-78.7 kJ moL(-1). L* parameter with the highest activation energy (200.08 kJ moL(-1)) was pointed out in this study. Also, a higher sensitivity to temperature for the antioxidant capacity is evidenced by higher activation energy (83.3 kJ moL(-1)). This study concluded that drying at high temperature (70 degrees C) with a short time promoted retentions in bioactive compounds.Öğe Optimization of hot-air and microwave drying process parameters for evaluation of phenolics and antioxidant activity in sliced white button mushroom (agaricus bisporus) using response surface methodology(North University Center Baia Mare, 2021) Atalay, Derya; Erge, Hande SelenThis study was conducted to investigate hot-air and microwave dryings on phenolics and antioxidant activity of dried white button mushroom slices (Agaricus bisporus) using the response surface methodology. It was also aimed to determine optimized drying conditions. In hot-air drying, total phenolics content reduced with corresponding increase in drying temperature and slice thickness, whereas in microwave drying, the total phenolics content increased with microwave power. Although the effect of drying temperature on antioxidant activity is not significant, there is a decrease in antioxidant activity as the slice thickness of the samples increases. Microwave power had also a significant linear effect on antioxidant activity of dried samples (p<0.01). Both increases and decreases in individual phenolic compounds were detected with the change of drying conditions and sample thickness. A quadratic model was well fitted to all responses. As a result of numerical optimization, optimum conditions for hot-air drier and microwave oven were suggested as 50 degrees C and 600 Watt having mushroom slices of 2 mm thickness, respectively. Our results show that the quality of dried mushroom depends on the drying method and conditions. Also, microwave drying is suitable method for drying of mushroom slices within a shorter time compared with hot-air drying.Öğe PEKTİN; KAYNAKLARI VE EKSTRAKSİYON YÖNTEMLERİ(2018) Atalay, Derya; Türken, Tuğba; Erge, Hande SelenBir heteropolisakkarit olan pektin; kıvam verici, jelleştirici, emülsifiye edici ve stabilize edici özelliklere sahipolmasından dolayı gıda endüstrisinde katkı maddesi olarak kullanılmaktadır. Ticari pektinler, genellikleturunçgil kabuğu, elma posası ve daha az oranda şeker pancarı posasından üretilmektedir. Pektinin, posa veyakabuklardan ekstrakte edilmesinde kullanılan en yaygın ve geleneksel yöntem asitle ekstraksiyondur. Sonyıllarda, pektin kaynaklarının yetersiz olması ve asit ekstraksiyonunun dezavantajlarından dolayı hem yenikaynak hem de yeni ekstraksiyon yöntemi araştırmaları önem kazanmıştır. Özellikle, meyve ve sebzeişletmeleri artıklarının değerlendirilmesi amacıyla nar, üzüm, havuç gibi yeni hammadde kaynakları ileekstraksiyon verimini artıracak mikrodalga destekli ekstraksiyon, ultrasonik destekli ekstraksiyon ve subkritik su ekstraksiyonu gibi yenilikçi teknolojilerin kullanımı çalışmalarda yer edinmiştir. Bu derlemekapsamında, son yıllarda dikkat çeken farklı pektin kaynakları ve ekstraksiyon yöntemleri derlenmiştir.Öğe Thermal degradation kinetics of bioactive compounds and visual color in raspberry pulp(Wiley, 2014) Sümmen, Mehmet Abdullah; Erge, Hande SelenThe effect of heating on degradation of some bioactive compounds (total monomeric anthocyanins, L-ascorbic acid and total phenolics) and color loss in raspberry pulp were investigated at 60, 70, 80 and 90C for 7 h. Total monomeric anthocyanins and L-ascorbic acid followed first-order kinetics, while a zero-order kinetic model was determined for the degradation of total phenolics. The first-order reaction was also described for the color loss in terms of Hunter a, b and C values. The activation energies for the degradation of raspberry anthocyanins, L-ascorbic acid and total phenolics were 49.3, 15.7 and 32.2 kJ/mol, respectively. Higher activation energies (49.0-75.5 kJ/mol) found for color loss indicates, this reaction is more sensitive to the temperature elevations than the other reactions.Öğe Thermal oxidation kinetics of refined hazelnut oil(Wiley, 2018) Solak, Rukiye; Turan, Semra; Kurhan, Şebnem; Erge, Hande Selen; Karabulut, İhsanIn this study, oxidation kinetics of refined hazelnut oil heated at the temperature range from 80 to 180 degrees C was evaluated. The changes in peroxide value, p-anisidine value, polymer triglyceride content, -tocopherol content, and color values during oxidation were best fitted to zero-order kinetic model. The rate constants for the p-anisidine value, polymer triglyceride content, and degradation of -tocopherol of hazelnut oil increased at the temperatures between 80 and 160 degrees C, while the rate constant for peroxide value decreased at the temperatures between 80 and 140 degrees C. The activation energies for the formation of peroxides (at 80-140 degrees C), secondary oxidation products such as alkenals, the polymer triglycerides, and degradation of -tocopherol were found as 47.49, 29.95, 52.65, and 14.22kJmol(-1), respectively. The induction period of hazelnut oil was observed to reduce with increasing oxidation times. The increase in the b* value with the oxidation time and temperature was attributed to the fact that the heating process intensified the yellow color of the oil.Öğe Yenilebilir kaplamaların taze kesilmiş meyve ve sebzelerde kullanımı(2020) Yüksel, Çiğdem; Atalay, Derya; Erge, Hande SelenTaze kesilmiş ürünler, hücrelerin ve dokuların zarar görmesinden dolayı hasat ve tüketim süreci arasında birçok faktöre karşı duyarlıdır. Bu ürünlerde renk değişimi, tekstür bozulması, vitamin kaybı ve mikrobiyal gelişim gibi sorunlar ortaya çıkabilir. Bu problemler nedeniyle, son yıllarda yenilebilir kaplamalar taze kesilmiş ürünlerin raf ömrünün artırılmasında potansiyel yöntemlerden biri olarak kabul edilmiştir. Yenilebilir kaplamalar; nem ve çözünmüş maddelerin geçişini, gaz alış-verişini, solunum ve oksidatif reaksiyon hızını azaltarak taze kesilmiş meyve ve sebzelerin raf ömrünün ve kalitesinin iyileştirilmesine katkıda bulunabilir. Bu makalenin amacı, taze kesilmiş ürünlerde yenilebilir kaplamaların kullanımını araştırmak ve derlemektir. Bu kapsamda; taze kesilmiş meyve ve sebzelerin önemi, üretimi, yenilebilir kaplamaların bileşimleri, uygulama yöntemleri ve avantaj/dezavantajları değerlendirilmiştir.
