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Öğe An innovative technique for extending shelf life of strawberry: Ultrasound(Elsevier Science Bv, 2013) Aday, Mehmet Seckin; Temizkan, Riza; Buyukcan, Mehmet Burak; Caner, CengizUltrasound is one of the newest nonthermal methods to extend shelf life of fresh fruits during storage. The effectiveness of ultrasound depends on wave frequency, power and treatment time. The present study was designed to determine the effect of different ultrasound powers (30 W, 60 W, 90 W) and treatment times (5 min, 10 min) on quality of strawberry. Oxygen concentration inside packages of strawberries which treated with 30 W and 60 W ultrasound powers were higher than 90 W and control (CNT) groups. A sharp increase in CO2 release rate was observed for the CNT and 90 W treatments during the storage. Attributes such as pH, total soluble solid content and color for the 30 Wand 60 W treatments were better than CNT and 90 W treatments. Decay incidence analysis confirmed that all ultrasound treatments were effective to reduce mold growth. The 30 W and 60 W treatments maintained better textural properties compared with 90 Wand CNT groups. FT-NIR analysis was used to quantify water and sugar content of strawberries. As a result, it was concluded that ultrasound power as high as 90 W resulted in detrimental effects on strawberry quality, while power levels between 30 W and 60 W had improved quality and can be used to extend shelf life of strawberry. (C) 2012 Elsevier Ltd. All rights reserved.Öğe Beyaz nektarin kalitesinin ısıl olmayan muhafaza yöntemleriyle korunması ve görüntü işleme teknikleriyle değerlendirilmesi(Çanakkale Onsekiz Mart Üniversitesi, Lisansüstü Eğitim Enstitüsü, 2017) Temizkan, Riza; Caner, CengizBu çalışmada, ısıl olmayan muhafaza yöntemlerinin (ozon, ultrases, elektrolize su ve bu uygulamaların çeşitli kombinasyonları) Çanakkale yöresine özgü bir ürün olan beyaz nektarin meyvesinin kalite kriterleri üzerine etkileri incelenmiştir. Bu amaçla, depolama süresince fiziko-kimyasal analizler (ağırlık kaybı, pH, suda çözünür kuru madde (briks), ambalaj içi gaz konsantrasyonu, bozulma-çürüme oranı, renk, tekstür ve FT-NIR) gerçekleştirilmiş ve görüntü işleme teknikleriyle renk ve morfolojik özellikler belirlenmiştir. Birinci bölümde; 1 ppm, 5 ppm, 10 ppm ve 20 ppm dozlarında ozon gazı uygulanmış ve yapılan analizler sonucunda, 5 ppm ve 1 ppm ozon uygulamaları avantaj sağlarken 10 ppm ve üzeri dozların beyaz nektarin kalitesi üzerinde olumsuz etki oluşturduğu belirlenmiştir. İkinci bölümde; 100 W, 200 W, 300 W ve 500 W güçlerinde ultrases uygulamaları gerçekleştirilmiş ve analiz bulgularınca 300 W uygulaması optimum parametre olarak saptanmıştır. Üçüncü bölümde; 50 ppm, 100 ppm, 200 ppm ve 400 ppm konsantrasyonlarında elektrolize su uygulamaları gerçekleştirilmiş ve 50 ppm konsantrasyonun optimum olduğu, 200 ppm ve üzeri dozların beyaz nektarinlerde tahribata neden olduğu ortaya konulmuştur. Dördüncü bölümde ise, ilk üç bölümde elde edilen optimum parametrelerin çeşitli kombinasyonları (O+US, O+ES, US+ES ve O+US+ES) uygulanmış ve en etkili grup olarak ozon-ultrases uygulamalarının kombinasyonu (O+US) belirlenmiştir. Ayrıca, güçlü sanitasyon ajanları olan ozon ve elektrolize su uygulamalarının birlikte kullanılmasının (O+ES ve O+US+ES) beyaz nektarinlerde antagonistik etki oluştuğu saptanmıştır. Çalışma sonucunda, ısıl olmayan muhafaza tekniklerinin optimum parametreler belirlenmek ön koşuluyla başarılı bir şekilde kullanılabileceği ve fiziko-kimyasal analiz bulgularını destekleyen görüntü işleme tekniklerinin objektif, hızlı ve hasarsız bir analiz yöntemi olarak kullanımının gıda sektörüne katkı sağlayacağı ortaya konulmuştur.Öğe Changes during ripening in chemical composition, proteolysis, volatile composition and texture in Kashar cheese made using raw bovine, ovine or caprine milk(Wiley, 2014) Temizkan, Riza; Yasar, Kurban; Hayaloglu, Ali A.Kashar cheeses were manufactured from pure ovine (OV), bovine (BV) and caprine (CP) milk, and the chemical composition, cheese yield, proteolysis, hardness, meltability and volatile composition were studied during 90days. Gross chemical composition, cheese yield and level of proteolysis were higher in OV cheeses than those of BV or CP cheeses. Glu, Val, Leu, Phe and Lys were the most abundant free amino acids (FAA) in the samples, and the concentrations of individual FAA were at the highest levels in OV cheeses with following BV and CP cheeses. Urea-PAGE patterns and RP-HPLC peptide profiles of the BV cheeses were completely different from the small ruminants' milk cheeses (OV or CP). Higher and lower hardness and meltability values were observed in CP cheeses, respectively. OV cheeses resulted in higher levels of the major volatile compounds. In conclusion, the Kashar cheese made using OV milk can be recommended due to high meltability, proteolysis and volatiles.Öğe Efficacy evaluation of ultrasound treatment on the postharvest storability of white nectarine by both physicochemical and image processing analyses(Elsevier Science Bv, 2019) Temizkan, Riza; Atan, Mustafa; Buyukcan, Mehmet Burak; Caner, CengizUltrasound is a non-thermal method to preserve the postharvest quality of fresh fruit during storage that is also non-toxic and environmentally friendly. In this study, the effects of ultrasound treated at 0, 100, 200, 300, and 500 W on the quality of white nectarine stored at 4 degrees C for 50 d were investigated. Additionally, image processing techniques were used as a means of qualitative analysis. Weight loss, pH, total soluble solids (TSS), in-package gas concentration, decay rate, instrumental color, texture, and Fourier transform near-infrared (FT-NIR) were measurements were done in this study. Color and morphological characteristics of white nectarines were also identified by image processing techniques. Based on the results of physicochemical analyses, ultrasound treatment at 300 W power best-maintained nectarine quality. The decay rate was found to be 20% in the control fruit (CNT) and 3,3% in the 300 W treatment at the end of the storage. These results were supported by color and morphological characteristics obtained by image processing techniques. Overall, the results indicated that the non-thermal ultrasound technique could be used to increase storage quality of white nectarines, and image processing techniques could be implemented as objective, rapid and non-destructive analysis methods by the food industry.Öğe Fonksiyonel Gıda Olarak Yumurta: Bileşenleri ve Fonksiyonel Özellikleri(2012) Yüceer, Muhammed; Temizkan, Riza; Caner, CengizFonksiyonel gıdalar, bilinen besleyici etkilerinin yanı sıra insan sağlığının iyileştirmede ve/veya hastalıkların engellenmesi üzerinde olumlu etkiler sağlayabilen ürünlerdir. Yapılarında bulundurdukları üstün biyolojik protein, vitamin ve mineraller, doğal aktif bileşenleriyle yumurta 'doğal fonksiyonel gıda' olarak tanımlanmaktadır. Yapılan bu çalışmada hayvansal kaynaklı en yaygın fonksiyonel doğal gıda olan yumurta ve yumurta bileşenleri, fonksiyonel özellikleri hakkında bilgiler derlenmiştir.Öğe Investigation of the morphological and color changes of damaged green plums during storage time using digital image processing techniques(Gazi Universitesi, 2015) Sinecen, Mahmut; Temizkan, Riza; Caner, CengizThe quality of green plums is directly affected by the uniformity of color and morphological characteristics which can be changed during harvest, handling, transportation and storage until they reach consumers. The determination of these characteristics is possible with image processing techniques. The advantages of this technique are being a simple, non-destructive and inexpensive methods that don’t require a complex apparatus. In this study, green plums are damaged at different rates (3 mm, 5 mm and 10 mm) by a texture analyzer and images are obtained at different storage periods. Non-damaged fruits were considered as control. Morphological and color features of these images are determined by using image processing technique with Matlab® Image Processing Toolbox and the findings are compared among groups. In particular, the 10 mm damaging rate showed statistically significant differences for most of the morphological and color features (p<0.05). Therefore, the results showed that image processing technique is usable to classify the green plums according to damage rate. © 2015, Gazi University Eti Mahallesi. All rights reserved.Öğe Investigation of the Morphological and Color Changes of Damaged Green Plums During Storage Time Using Digital Image Processing Techniques(Gazi Univ, 2015) Sinecen, Mahmut; Temizkan, Riza; Caner, CengizThe quality of green plums is directly affected by the uniformity of color and morphological characteristics which can be changed during harvest, handling, transportation and storage until they reach consumers. The determination of these characteristics is possible with image processing techniques. The advantages of this technique are being a simple, non-destructive and inexpensive methods that don't require a complex apparatus. In this study, green plums are damaged at different rates (3 mm, 5 mm and 10 mm) by a texture analyzer and images are obtained at different storage periods. Non-damaged fruits were considered as control. Morphological and color features of these images are determined by using image processing technique with Matlab (R) Image Processing Toolbox and the findings are compared among groups. In particular, the 10 mm damaging rate showed statistically significant differences for most of the morphological and color features (p<0.05). Therefore, the results showed that image processing technique is usable to classify the green plums according to damage rate.Öğe Kaşar peynirinin bileşim, proteoliz, fonksiyonel ve duyusal özellikleri üzerine inek, koyun ve keçi sütü kullanımının etkisi(Çanakkale Onsekiz Mart Üniversitesi, 2012) Temizkan, Riza; Yaşar, KurbanBu çalışmada, inek, koyun ve keçi sütleri kullanılarak Kaşar peynirleri üretilmiş ve 90 gün süre ile olgunlaştırılmıştır. İnek ve keçi sütü kullanılarak üretilen peynirlerin randımanları birbirine yakın, koyun sütü ile üretilen peynirlerin randımanları ise daha yüksek bulunmuştur. Farklı süt türlerinin kullanımı, Kaşar peynirlerinin % 5'lik fosfotungstik asitte çözünen azot (PTA-ÇA) ve duyusal özelliklerden renk/görünüş özelliklerini etkilemezken; pH, titrasyon asitliği, kurumadde (KM), kül, yağ, KM'de yağ, tuz, KM'de tuz, protein, KM'de protein, suda çözünen azot (SÇA), % 12'lik trikloroasetik asitte çözünen azot (TCA-ÇA), olgunlaşma indeksi katsayısı, toplam serbest amino asit miktarı, sertlik, erime, renk ve duyusal özelliklerinden beğeni sıralaması, lezzet ve yapı özelliklerini önemli derecede etkilemiştir.Kaşar peynirlerinin bileşiminin belirlenmesine yönelik analizler sonucunda, keçi peynirinin KM ve protein içeriğinin diğer peynir gruplarından daha fazla olduğu saptanmıştır. Kaşar peynirleri için en önemli fonksiyonel özelliklerden biri olan erime özelliğine en fazla koyun peynirinin sahip olduğu belirlenmiştir. Aynı zamanda, koyun peyniri daha fazla proteolize uğramıştır. Duyusal analizler sonucunda, panelistlerce en çok beğenilen Kaşar peyniri inek sütü ile üretilen Kaşar peyniri olmuştur. Olgunlaşma süresine bağlı olarak peynirlerin titrasyon asitliği, SÇA, TCA-ÇA, PTA-ÇA, olgunlaşma indeksi katsayısı, toplam serbest amino asit ve erime oranları artarken; L değerleri, ß-kazein ve ?s1-kazein oranları ile sertlik değerleri azalmıştır.Anahtar sözcükler: Kaşar Peyniri, İnek-Koyun-Keçi Peyniri, Proteoliz, Fonksiyonel, ErimeÖğe Potential of antimicrobial active packaging 'containing natamycin, nisin, pomegranate and grape seed extract in chitosan coating' to extend shelf life of fresh strawberry(Elsevier, 2016) Duran, Merve; Aday, Mehmet Seckin; Zorba, Nukhet N. Demirel; Temizkan, Riza; Buyukcan, Mehmet Burak; Caner, CengizIn this study, chitosan (CH) coatings as carrier of nisin (NS), natamycin (NT), pomegranate (PE) and grape seed extract (GE) were used to maintain quality and extend shelf life of fresh strawberry. The samples were analyzed in terms of gas composition inside packaging, pH, total soluble solid content, water activity, color, texture, FT-NIR and microbial counts for up to 40 days at 4 degrees C. The experiments showed that all coating materials preserved the quality of fresh strawberry compared to untreated ones. Among the treatments, incorporation of the natamycin in the chitosan coating (CH+NT) reduced the O-2 consumption of the fruit and showed better effects on delaying changes of pH, total soluble solid content, water activity and microbial counts. The incorporation of different antimicrobial agents into chitosan matrix did not reveal any significant effect on lightness (L*) and redness (a*) of strawberry. Among the treatments, CH + PE and CH + NT showed significantly higher antimicrobial effect against the mesophilic bacteria and yeast and mold. As a general result, antimicrobial active packaging based on the combination of chitosan coating with antimicrobial agents increased the shelf life of fresh strawberry compared to uncoated fruit. (C) 2016 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.Öğe Quick vacuum drying of liquid samples prior to ATR-FTIR spectral collection improves the quantitative prediction: a case study of milk adulteration(Wiley, 2018) Ayvaz, Huseyin; Temizkan, RizaAttenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy-based prediction methods were previously shown to be a practical alternative to determine milk adulteration. However, milk in general contains high amount of water and infrared absorptions sourcing from water dominate the mid-infrared spectrum of the milk, preventing the other key vibrations in fingerprint region from escalating. Therefore, we aimed at evaluating the efficacy of a 30-s vacuum treatment on liquid milk aliquots prior to spectral collection and compare the results with no vacuum-applied spectra. Overall, quick vacuum treatment approach led to better-resolved peaks in the fingerprint region of the spectra compared with water-dominated spectra of milk with no vacuum application. Considering the residual predictive deviation (RPD) values obtained, vacuum treatment has significantly improved the performance of the models in prediction indicating that quick vacuum approach would be beneficial if implemented for routine determination for milk adulteration.Öğe Raman Spectroscopy for Food Quality: Assessment Uncovering Adulteration and Ensuring Authenticity(CRC Press, 2024) Ayvaz, Huseyin; Yao, Siyu; Morta, Mustafa; Temizkan, Riza; Akpolat, Hacer; Rodriguez-Saona, Luis E.The globalization of the food market, the prevalence of economically motivated adulteration, and the scarcity of high-value food sources have posed significant challenges to ensuring food authenticity in the industry. The assessment of food authenticity has now become a matter of utmost importance, necessitating the adoption of rapid and robust methods. While well-established techniques are available for analysis, many are not always feasible because of the need for high-priced instrumentation and proficient operators, excessive time requirements, and the destructive nature of the methods. However, Raman spectroscopy has been positioned as an attractive technology offering high-speed and nondestructive fingerprinting capabilities to monitor sample characteristics of foods. Improvements in optical technology and portable instruments have allowed field-deployable devices and have made it practical to detect adulteration from production to the market. An extensive literature has demonstrated the convenience and efficacy of these instruments in fulfilling the needs of the food industry. This chapter highlights the recent advancements in research studies focusing on the utilization of Raman spectroscopy for the rapid determination of food adulteration and authentication. These developments showcase the potential of Raman spectroscopy as a valuable tool in addressing the challenges posed by food fraud. The ongoing progress in Raman spectroscopy and its applications in food authenticity assessment represents a significant step forward in combating adulteration and ensuring the integrity of our food supply. Further research and technological advancements in this field will enhance the capabilities of Raman spectroscopy, providing the industry with increasingly reliable, efficient, and practical methods to combat food adulteration and authenticate the foods we consume. © 2025 selection and editorial matter, Ugur Tamer, Mustafa Culha, and smail Hakki Boyaci; individual chapters, the contributors.Öğe Rapid detection of milk fat adulteration in yoghurts using near and mid-infrared spectroscopy(Elsevier Sci Ltd, 2020) Temizkan, Riza; Can, Aygul; Dogan, Muhammed Ali; Mortas, Mustafa; Ayvaz, HuseyinBoth Fourier-transform near-infrared (FT-NIR) and mid-infrared (FT-MIR) spectroscopy with chemometrics were used for the fast detection of milk fat adulteration in yoghurts without sample preparation. Soft independent modelling of class analogy models of both NIR and MIR spectra showed successful detection of milk fat adulteration and identification of the type of adulterant oils. Partial least squares regression models of a representative adulterant yielded high correlation coefficients (above 0.98), low standard error of prediction (lower than 7.12%) and high residual predictive deviation values (above 4.35) for both NIR and MIR spectra. Additionally, regardless of the source of adulterant oils used, separate NIR and MIR PLSR models were developed for quantification of milk fat ratio (%) in yoghurts as an alternative approach to measuring the level of adulterant oil (%); NIR spectroscopy was found to be superior in these models. (C) 2020 Elsevier Ltd. All rights reserved.Öğe Rapid discrimination of Turkish commercial hazelnut (Corylus avellana L.) varieties using Near-Infrared Spectroscopy and chemometrics(Elsevier, 2022) Ayvaz, Huseyin; Temizkan, Riza; Genis, Huseyin Efe; Mortas, Mustafa; Genis, Duygu Ozer; Dogan, Muhammed Ali; Nazlim, Burak AlptugClassification of hazelnuts as per their varieties is traditionally made based on subjective phenotypic observations. However, various factors easily affect these observations, including environmental conditions and the growth phase of hazelnuts, making it difficult to separate the varieties. Furthermore, the distinction among the varieties becomes far more challenging in the case of shelled hazelnut kernels, where trade is much more common than hazelnuts in-shell. Nevertheless, literature studies imply that there are apparent differences among the chemical compositions of different hazelnut varieties along with the visual appearances. Thus, developing an analytical method allowing these differences to be determined quickly and objectively would be valuable. Accordingly, the potential of using Near-Infrared Spectroscopy (NIRS) with chemometrics as a fast, convenient, and reliable method in discriminating commercially important hazelnut varieties grown in Turkey has been investigated in this research. A total of 280 hazelnut samples belonging to seven distinct varieties in Turkey were employed in the study. NIR spectra of the hazelnuts were collected from three physical states of hazelnuts as (1) in-shell, (2) shelled, and (3) white interior of split hazelnut kernels. Using the collected spectra and chemometric methods (Partial Least Squares-Discriminant Analysis (PLS-DA) and Logistic Models), calibration models were developed using a training set (n = 210) and validated with a test set (n = 70). The results have indicated that all NIR spectra-based PLS-DA and Logistic Models with MultiClass Fisher's Linear Discriminant Analysis (FLDA) pre-processing technique could accurately determine the variety of unknown hazelnuts at 100 % in either of the three tested physical states of the samples. Accordingly, these approaches can be utilized by the sector that is concerned about economic loss as more reliable and objective methods compared to the traditional analysis of hazelnut varieties, which are generally made via subjective visual assessment.Öğe Role of Ozone Concentrations and Exposure Times in Extending Shelf Life of Strawberry(Taylor & Francis Inc, 2014) Aday, Mehmet Seckin; Buyukcan, Mehmet Burak; Temizkan, Riza; Caner, CengizEfficiency of three aqueous ozone concentrations (0.075 ppm, 0.15 ppm, 0.25 ppm) and two exposure times (2 and 5 min) were investigated for maintaining strawberry quality. Exposure to 0.075 ppm and 0.15 ppm ozone delayed the changes in pH, total soluble solids, firmness and electrical conductivity. All ozone treatments prevented mold growth during storage. However, the 0.25 ppm ozone treatment caused loss of strawberry quality due to high ozone concentration. The results have shown that; low (0.075 ppm) and middle (0.15 ppm) ozone concentrations can be applied to extend the shelf-life of strawberries by at least 3 weeks under refrigerated conditions.Öğe Structure and Stability of Fish Oil Organogels Prepared with Sunflower Wax and Monoglyceride(Japan Oil Chemists Soc, 2015) Ogutcu, Mustafa; Temizkan, Riza; Arifoglu, Nazan; Yılmaz, EminThe aims of this study were to develop fish oil (FO) organogels with sunflower wax (SW) and monoglyceride (MG), and compare them with a commercial margarine (CM). The organogels were stored at 4 and 20 degrees C for 90 days and their storage stability was investigated. The color values, oil binding capacity, crystal formation time, solid fat content, thermal properties and crystal structures of the organogels were measured. During storage, their textural properties and peroxide values were monitored. The melting temperature of the MG organogels was found similar to that of the CM sample. Otherwise, the melting points of the MG gels were lower than those of the SW gels. Crystal morphology of the CM sample was found similar to MG gels by X-ray measurements. The firmness values of the SW organogels were higher than those of the MG gels. The peroxide values of all gels were within the legal limits.
