Hasan Vardin

Authentication of pomegranate juice concentrate using FTIR spectroscopy and chemometrics

Fourier transform infrared (FTIR) spectroscopy and chemometric techniques were used to detect the adulteration of pomegranate juice concentrate (PJC) with grape juice concentrate (GJC). The main differences between PJC and GJC infrared spectra occurred in the 1780-1685cm(-1) region, which corresponds to CO stretching. Principal component analysis of the spectra was used to: (1) differentiate pure PJC and GJC samples and (2) classify adulterated (containing 2-14% vol/vol GJC) and pure PJC samples. Two principal components explained 99% of the variability in each of these applications. Partial least square analysis of the spectra resulted in prediction of the GJC adulterant concentration in PJC with a correlation coefficient, R(2), of 0.9751. Partial least square analysis of spectra could also predict % titratable acidity and total solids in PJC with correlation coefficients of 0.9114 and 0.9916, respectively. Therefore, FTIR and chemometrics provide a useful approach for authenticating pomegranate juice concentrate.

Synthesis and accumulation of anthocyanins in sour cherries during ripening in accordance with antioxidant capacity development and chalcone synthase expression

AbstractPhytonutrient metabolism in sour cherries takes place during fruit ripening. This study demonstrated that total phenolic–flavonoid contents decline during ripening while total anthocyanin content significantly increases at the same period. There were no detectable anthocyanins in green cherry fruits. Anthocyanin biosynthesis started concurrently with color formation. Cyanidin-3-glucosylrutinoside and cyanidin-3-rutinoside were the early anthocyanins accumulated in fruits and were accompanied with cyanidin-3-sophoroside and cyanidin-3-glucoside in fully ripe fruits. Phenylpropanoid pathway involves anthocyanin biosynthesis, and chalcone synthase (CHS) is one of the key enzymes regulating the pathway. Three CHS genes (PcChs1, PcChs2, PcChs3) were isolated from sour cherry genome, and their transcription profiles were determined using the RT-PCR approach. There was no CHS gene expression before breaker stage, and PcChs1, PcChs2, PcChs3 transcription were upregulated in parallel with pigmentation in sour cherry cells and PcChs1 had the highest transcripts in fully ripe fruits.

THE EFFECT OF TEMPERATURE AND METHOD OF DRYING ON ISOT (URFA PEPPER) AND ITS VITAMIN C DEGRADATION KINETICS

This study investigated drying and vitamin C degradation kinetics in isot (red peppers) at different temperatures (55, 65 and 75°C) and conditions (vacuum and hot air drying). The drying temperature and method had a significant effect on the loss of vitamin C. Vacuum dried samples at 55°C retained the highest quantity of vitamin C, while the samples dried at 75°C in a cabinet dryer lost the highest amount of vitamin C. The results showed that vitamin C is especially sensitive to the presence of oxygen and higher temperatures. The Weibull model was found to provide the mathematical equation best describing the ascorbic acid degradation kinetics in red peppers, while the Page model best reflected the drying kinetics.

Farklı pH ve Sıcaklık Değerlerinin Pichia Pastoris'de Rekombinant Ekspanzin Üretimine ve Kuru Hücre Konsantrasyonuna Etkisi

Bu calisma kapsaminda rekombinant Ekspanzin uretimi amaciyla domatesten izole edilen LeExp1 geni Pichia pastoris mayalarina pPIC9K vektoru vasitasiyla aktarilmistir. Ekspresyon kosullari 20, 25, 30°C ve pH 4.0, 5.0, 6.0 ve 7.0 degerleri icin ayri ayri saglanmistir. Fermentasyon ozutlerinin Biomass analizi ve Bradford assay deneyleri sonucunda toplam rekombinant protein miktarlari ve toplam hucre konsantrasyonlari belirlenmistir. Farkli pH ve sicaklik degerlerinin rekombinant protein uretim miktarina ve toplam hucre konsantrasyonuna olan etkileri incelenmistir. Deneysel sonuclara gore maksimum rekombinant ekspanzin uretimi icin P. pastoris mayalarinin optimum fermantasyon kosullari 25 o C sicaklik ve pH 7.0 olarak tespit edilmistir.

Sour Cherry By-products: Compositions, Functional Properties and Recovery Potentials – A Review

Abstract Sour (tart) cherry is an industrial fruit where a considerable amount of by-products remain after processing. Sour cherry by-products consist of pomace (skin and flesh) and seeds (pit, stone) which remain after the fruit juice and IQF processes. Sour cherry pomace is characterized with a high content of phenolic compounds and the seed constitutes a high oil yield with beneficial effects on human health because of their antioxidant, antimicrobial, and anti-inflammatory properties. There has been a great interest in sour cherry by-products due to the increasing production rate of sour cherry worldwide and the increasing efforts on seeking bioactive compounds from natural sources as functional food. Thus, there have been a number of studies regarding the sour cherry pomace and sour cherry seed, especially in the last five years. The present review summarizes the chemical, biological, functional, and technological properties of the sour cherry pomace and sour cherry seed with their current and potential applications.