Osman Kola

Bioactive compounds and antioxidant potential in tomato pastes as affected by hot and cold break process

The effects of hot and cold break industrial tomato paste production steps on phenolic compounds, carotenoids, organic acids, hydroxy methyl furfural (HMF) and other quality parameters of tomato pastes were investigated in this study. Phenolic compounds, carotenoids, organic acids, and HMF analyses were performed with LC-DAD-ESI-MS/MS and LC-DAD-RID was used for the sugar analyses. Furthermore, the antioxidant capacities of tomato pastes were assessed via the DPPH and ABTS methods. The increase of phenol acids at the processing steps of cold break production method was higher than the hot break production method. According to PCA analyses, phenolic acids characterized cold break tomato pastes while hot break tomato pastes were characterized by flavanols and flavanones. The total amount of organic acids decreased with processing and the loss of organic acids was lower in cold break pastes. Heating and evaporation were determined as the most important processing steps in which the amount of different quality parameters change.

Quantitative determination of phenolic compounds using LC-DAD-ESI-MS/MS in cv. Ayvalik olive oils as affected by harvest time

The purpose of this study was to evaluate and compare the effects of early (EHVOO) and late harvest (LHVOO) dates on phenolic composition of virgin olive oils (VOO) from the Ayvalik (Edremit) variety. Liquid chromatography combined with a diode array detector and ion spray mass spectrometry in the tandem mode (LC-DAD-ESI-MS/MS) with negative ion detections was used for identification of phenolic compounds in the VOOs. A total of 14 phenolic compounds were identified and quantified in VOOs, including phenolic alcohols (2), phenolic acids (4), secoiridoids (5), and flavonoids (3). Secoiridoids followed by phenolic alcohols and flavonoids were the most abundant compounds of the VOOs. Among secoiridoids 3.4-DHPEA-EDA and 3.4-DHPEA-EA were the most dominant compounds. The antioxidant capacity of VOOs was determined by two different methods, including DPPH and ABTS. The antioxidant capacity of LHVOO was found to be higher than that of EHVOO. Additionally, significant linear correlation was confirmed between the phenolic content and antioxidant capacities of VOOs.

HPLC DETERMINATION OF CAROTENOID, ORGANIC ACID, AND SUGAR CONTENT IN PEPINO (Solanum muricatum) FRUIT DURING THE RIPENING PERIOD

Pepino, Solanum muricatum, is a herbaceous plant of South American origin [1, 2]. Currently, several commercial varieties are being developed in New Zealand and Australia through selection and breeding (e.g., Suma, Miski, Lincoln Long, Golden Litestripe, etc.), while other cultivars (e.g., El Camino and Schmidt) are direct introductions of material grown in Chile [3]. The pepino (Solanum muricatum Aiton, Solanaceae) is a little-known crop from the tropical and subtropical Andes esteemed for its edible fruits, which are aromatic, juicy, scented, mildly sweet, and greatly varying in size, shape, and color depending on the cultivar [1, 2]. The fruit matures 30 to 80 days after pollination. Its color starts with green and during ripening changes to golden yellow covered with purple stripes [4]. El-Zeftawi et al. [5] reported that the fruit often fails to ripen normally and thus fails to develop its characteristic flavor after harvest. Hence, appropriate harvesting of pepino fruit is essential for high pepino quality [6–8]. The pepino is said to have medicinal properties. It is a good antiscorbutic since it contains vitamin C (25–70 mg/100 mL) at higher levels than normally found in most fruits [9–11]. This work is a first step to identify and quantify organic acids and sugars and some properties in pepino fruits and fruit juices (cv. Miski) from Turkey using HPLC methods. The overall objective of the study was to determine the quality characteristics of pepino fruits during the maturation period and to identify objective indices of the properties of both the fruit and the juice. Pepino fruits (cv. Miski) were harvested at three stages (green, strapped green, mature) from December 2009 to February 2010 at Akyazi and Antalya, Turkey. Pepino fruits were harvested and kept at a temperature of 5 C until analysis. All chemicals and solvents were obtained from Sigma Chemical Co. (St Louis, MO, USA) and Merck (Darmstadt, Germany). Pepino fruits (cv. Miski) were 168.2–258.2 g/fruit weight, 6.50–8.78 cm in diameter, and 8.17–9.32 cm long. The juice yield (%) of pepino samples varied from 43.0 to 51.0% (Table 1). During the maturation period a small increase in fruit weight, fruit width, and fruit length was detected. Antalya pepinos were approximately 10% more massive than Akyazi pepinos at the mature stage. The chemical properties of pepino juice samples are given in Table 1. In this study, the total acidity (%) in pepino fruits was determined as ranging from 0.06 to 0.08, the Brix (total soluble solids, SSC) from 4.00 to 7.10, and pH values from 4.89 to 5.84. The total soluble solids content of the two different pepinos increased during the maturation period. Gonzalez et al. [7] found pH values ranging from 4.74–5.40 and 4.89–5.14 in the sweet round and sweet long kinds. In their study on the quality and physiological behavior of pepinos, Lizana and Levano [12] reported that typical Chilean pepinos had 8.5% soluble solids when ripe. De Arriola et al. [9] also reported a total acidity of 0.06%, a Brix (total soluble solids) of 9.5%, total sugars of 4.06 g/100 g, and ascorbic acid of 34.25 mg/100 g in ripe pepino fruits of a local selection.

Characterization of the key aroma compounds in tomato pastes as affected by hot and cold break process

The popular flavor of tomato and its products are primarily due to a complex mixture of acids, sugars, amino acids, minerals, and volatile compounds. Within this mixture, the aroma of tomato and its products is an important attribute that greatly influences consumer acceptability and preference. In the present study, tomato and its two types of pastes, produced from hot and cold break methods, were subject to sensory profiling, aroma, and aroma-active compounds analysis. The key aroma compounds in tomato and its two types of pastes were characterized by application of direct solvent extraction with dichloromethane/solvent assisted flavor evaporation (SAFE), gas chromatography–mass spectrometry–olfactometry (GC–MS–O) technique and aroma extract dilution analysis (AEDA). Fresh tomato and its paste volatiles were composed of alcohols, aldehydes, lactones, carboxylic acids, ketones, furans, esters, volatile phenols, 13-C norisoprenoid, terpene, and pyrrols. Via AEDA application, a total of 21 and 13 key odorants were detected in tomato and its pastes, respectively. In tomato pastes, lower numbers of aroma-active compounds than in fresh tomato were determined. The most important difference of aroma-active compounds in tomato and its pastes was hexanal, (Z)-3-hexenal, 2,3-butanediol, (Z)-3-hexenol, (E)-2-octenal, benzaldehyde, (E,Z)-2,6-nonadienal, methyl salicylate, β-ionone, 5-penthyl-2-(5H)-furanone and eugenol was not detected in tomato paste samples. On the basis of flavor dilution (FD) factors obtained by AEDA, the most powerful aroma-active compounds were (Z)-3-hexenal (FD = 512; green-grassy), 4-methyl-(5H)-furan-2-one (FD = 512; fruity), β-ionone (FD = 512; floral-violet) in tomato; 6-methyl-5-hepten-2-one (FD = 1024; green-leafy) in cold break tomato paste and furfural (FD = 512; pungent) in hot break tomato paste. In the sensory analysis, the tomato paste produced with the cold processing method was more acclaimed in terms of color, smell, taste and fruity aroma than the paste produced via the hot processing method.

Altıntop dilim konservesi üretiminde dilim zarının pektolitik ve sellülotik enzimlerle uzaklaştırılması

In this study, effects of combination of pectinase and cellulase on the removal of grapefruit membrane were searched. Comparisons were made with chemical (NaOH) method; considering the quality of final product and applicability in the industry. On the removal of segment membrane, both the concentration of Pectinex Ultra SpL and Celluclast 1.5 L and treatment period were found to be effective. In the process of removal of segment membrane by enzyme solutions and NaOH, the best results were obtained by using of Pectinex Ultra SpL at 2% and Celluclast 1.5 L at 1% concentrations and 30 min. treatment. Segments peeled by enzymatic treatments were found to be superior organoleptically over the segments of NaOH treatment.

Removing segment membrane with pectolytic and cellulotic enzymes in canned grapefruit segment production

In this study, effects of combination of pectinase and cellulase on the removal of grapefruit membrane were searched. Comparisons were made with chemical (NaOH) method; considering the quality of final product and applicability in the industry. On the removal of segment membrane, both the concentration of Pectinex Ultra SpL and Celluclast 1.5 L and treatment period were found to be effective. In the process of removal of segment membrane by enzyme solutions and NaOH, the best results were obtained by using of Pectinex Ultra SpL at 2% and Celluclast 1.5 L at 1% concentrations and 30 min. treatment. Segments peeled by enzymatic treatments were found to be superior organoleptically over the segments of NaOH treatment.