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Öğe Application of Polypropylene-Based Nanocomposite Films for Sliced Turkish Pastrami under Vacuum/Modified Atmosphere Packaging: A Pilot Study(Mdpi, 2020) Ayas, Gulsum Erol; Ayhan, Zehra; Duraccio, Donatella; Silvestre, Clara; Cimmino, SossioThe purpose of this study was to investigate the effects of polypropylene (PP)-based nanomaterials with improved barrier properties by nanoclay and antimicrobial properties by poly-beta-pinene (P beta P) on the quality and shelf life of sliced pastrami as an alternative to the commercial multilayered materials. Sliced pastrami was packaged using nanocomposite films with and w/o P beta P, and multilayered material under air, modified atmosphere packaging (MAP) and vacuum. Packaged products were screened for microbiological, physicochemical and sensory quality at 4 degrees C for 6 months. Salmonella spp., Clostridium perfringens and coagulase positive Staphylococus aureus were not detected in the products during entire storage. No yeast and mold growth occurred for entire storage using antimicrobial nanocomposite and multilayer material under vacuum. The antimicrobial effect of P beta P on the pastrami was higher under vacuum compared to MAP applications suggesting that direct contact of the material is required with the food surface. Thiobarbituric acid reactive substances (TBARS) of pastrami under vacuum were lower than those of MAP applications. The initial carbonyl content of the product was determined as 3.38 nmol/mg and a slight increase was observed during storage period for all applications. The shelf life of pastrami is suggested as 150 days using P beta P containing nanomaterials under vacuum, which is longer than the shelf life of a commercial product on the market using multilayer materials.Öğe Design, construction and validation of a sanitary glove box packaging system for product shelf-life studies(Blackwell Publishing Ltd, 2001) Ayhan, Zehra; Streaker, Charles B.; Zhang, Q. HowardA glove box has been constructed as part of an integrated pilot plant scale pulsed electric field processing and packaging system to facilitate studies of product shelf-life with selected packaging materials. The glove box was sanitized using combination of hydrogen peroxide and germicidal UV light. A HEPA air filter provided positive pressure of bacteria-free air. Nonselective nutrient broth was sterilized and filled into presanitized bottles inside the glove box. Negative and positive controls were included in the experiment. All bottles were incubated at 22C and 37C for two weeks and checked for microbial growth by measuring optical density at 600 nm using a spectrophotometer and by plating on plate count agar and potato dextrose agar for total aerobic and, yeast and mold counts, respectively. No turbidity or microbial growth was observed in the media filled in the sanitized bottles using the sanitized glove box at 22 and 37C. PEF processed orange juice using this system had a shelf-life of more than 16 weeks at 4C.Öğe Drying Characteristics and Quality Parameters of Microwave-Dried Grated Carrots(Springer, 2012) Arikan, Mehmet Fatih; Ayhan, Zehra; Soysal, Yurtsever; Esturk, OkanThe effectiveness of various microwave-convective drying treatments was compared with convective drying to determine the most favourable treatments in terms of drying kinetics, specific energy consumption and dried product quality of grated carrots. The quality of the dried products differed among drying treatments depending on the microwave power level, pulse ratio and drying temperature. The intermittent microwave-convective drying at ambient temperature with a pulse ratio of 3.0 at 2.23 W g(-1) provided considerable savings in drying time and specific energy consumption when compared to convective drying and produced high-quality product with better physical (colour and texture) and sensory attributes for carrots. The intermittent microwave-convective drying conducted at lower drying temperature with relatively long power-off time resulted in a more stable and gentle drying process and could be preferred to produce high-quality products.Öğe Drying of sage (Salvia officinalis L.) inflorescences by intermittent and continuous microwave-convective air combination(Gaurav Soc Agricultural Research Information Centre-Aric, 2011) Esturk, Okan; Arslan, Mehmet; Soysal, Yurtsever; Uremis, Ilhan; Ayhan, ZehraThe effect of microwave-convective air (M-CA) drying (continuous and intermittent) and convective air (CA) drying of sage (Salvia officinalis L.) inflorescences on drying kinetics and essential oil content was studied. For M-CA drying, four pulse ratio levels (PR1, PR2, PR3 and PR4) at 25 degrees C drying air temperature were used. The average drying rates were 0.211, 0.105, 0.067 and 0.053 kg H2O/kg DM/min for PR1, PR2, PR3 and PR4, respectively. The experimental data were fitted to nine different moisture ratio (MR) models to describe the drying kinetics under various drying conditions. Page model was found satisfactory to describe the drying curves of sage inflorescences. The total quantity of essential oils of sage inflorescences decreased considerably during M-CA drying, whereas the loss of essential oils was limited during CA drying. Compared to shade drying, two essential oil components, sabinene and p-cymene, were lost during CA drying. On the other hand, in addition to these two, alpha-pinene, campene, beta-pinene, limonene, gamma-terpinene, camphor, bornyl acetate, alpha-copaene, gamma-cadinene, delta-cadinene and caryophyllene oxide were disappeared during M-CA drying. M-CA drying may not be proper technique for drying of sage inflorescences when essential oil content is important.Öğe EFFECT OF MODIFIED ATMOSPHERE PACKAGING AND STORAGE TIME ON PHYSICAL AND SENSORY PROPERTIES OF SLICED SALAMI(Wiley, 2009) Esturk, Okan; Ayhan, ZehraThe objective of this study was to investigate the quality properties of sliced and modified atmosphere-packaged salami during refrigerated storage. Salami was sliced and packaged under air and three modified atmosphere packaging (MAP) compositions (100% N-2; 50% CO2, 50% N-2; 5% O-2, 25% CO2, 70% N-2) in polypropylene trays sealed with polyethylene terepthalate/polyvinylidene chloride/oriented polypropylene. Headspace oxygen and carbon dioxide (%), physical (color and texture), chemical (pH) and sensory properties were analyzed for 20 days at 4C. The results showed that CO2 concentration (%) decreased after 5 days of storage for MAP applications with high CO2, which was attributed to the solubility of CO2 in the salami. The pH did not significantly change during storage at all applications (P > 0.05). While L values increased, a and b values decreased during storage. The MAP applications with no oxygen received higher panelist scores and provided better quality characteristics than air and 5% O-2, 25% CO2, 70% N-2 for 15 days.Öğe Effect of modified atmosphere packaging on the quality and shelf life of minimally processed carrots(2008) Ayhan, Zehra; Eştürk, Okan; Taş, EmelThe objective of this study was to investigate the effect of modified atmosphere packaging on the quality and shelf life of minimally processed carrots during cold storage. Ready-to-eat carrots (Nantes) prepared by manual peeling and automatic slicing were packed with passive (in air) and active modified atmospheres at low (5% O2, 10% CO2, 85% N2) and high oxygen concentrations (80% O2, 10% CO2, 10% N2). Minimally processed carrots were packed in polypropylene (PP) trays sealed with PP based film. Microbial, chemical, physical, and sensory analyses were conducted in carrots for 21 days at 4 °C. There was no yeast or mold growth during the 21 days of storage; however, the growth of mesophilic aerobic bacteria was observed at all treatments. The carrots packed with high oxygen and passive MAP retained quality properties better compared to low oxygen. The whiteness index did not significantly change during the 21 days of storage in all applications, indicating the good retention of orange color. The texture values declined for both passive and active MAP applications after 14 days of storage indicating a significant softening (P ≤ 0.05). According to oxygen level in the headspace and sensory results, shelf life of minimally processed carrots is suggested as 7 days for high oxygen and passive MAP application; however, it is limited to only 2 days for modified atmosphere with low oxygen.Öğe Effects of PP-based Nanopackaging on the Overall Quality and Shelf Life of Ready-to-eat Salami(Wiley, 2017) Nalcabasmaz, Serra; Ayhan, Zehra; Cimmino, Sossio; Silvestre, Clara; Duraccio, DonatellaA total of 1% nanoclay containing polypropylene ( PP)-nanocomposite and 1% nanoclay plus 5% poly-beta-pinene (P beta P) containing PP-active-nanocomposite materials were produced and tested for packaging of sliced salami. The sliced salami was packaged using both nanofilms and multilayer film of PP/PA/EVOH/PE under vacuum, modified atmosphere packaging under 50% CO2 and 50% N-2 and air and stored at 4 degrees C for 90 days. During storage, headspace gas composition; microbial, physical and chemical analyses; and sensory evaluation were performed. The antimicrobial effect of P beta P containing nanomaterial was pronounced under vacuum, and no bacterial growth was observed for 75 days. An a* value decreased notably in all applications during storage and preserved best by the multilayered material under vacuum and high CO2. Thiobarbituric acid reactive substances (TBARS) were 0.63 mg MDA/kg after the processing and gradually increased at all applications during increased storage. TBARS values of all vacuum applications were lower than that of modified atmosphere packaging applications. Rancid taste development was determined by sensory panelists when TBARS values were higher than 0.80 mg MDA/kg on the 90th day. There was no significant moisture loss, and no increase in hardness was determined during the whole storage time. The longest shelf life was 75 days for the sliced salami under vacuum and high CO2 using the multilayer material. P beta P containing nanomaterial provided 50 days of shelf life under vacuum, which is commercially considerable. Copyright (C) 2017 John Wiley & Sons, Ltd.Öğe FARKLI AMBALAJ MATERYALLERİ ve VAKUM/MODİFİYE ATMOSFER AMBALAJLAMANIN DİLİMLENMİŞ HATAY PEYNİRİNİN KALİTESİ VE RAF ÖMRÜNE ETKİSİ(2023) Toplu, Bengisu; Sıçramaz, Hatice; Ayhan, ZehraBu çalışmada ambalajsız olarak satışa sunulan ve yöresel bir peynir çeşidi olan Hatay peynirinde uygun ambalaj malzemesi ve teknolojilerinin kullanımı ile daha kaliteli ve uzun raf ömrüne sahip bir ürün elde edilmesi hedeflenmiştir. Bu nedenle dilimlenmiş peynir örnekleri modifiye atmosfer (%50 CO2 ve %50 N2), hava (%21 O2 ve %79 N2) ve vakum altında üç farklı geçirgenlikte ambalaj malzemeleri (Koekstrude PA/PE, OPET/OPA/CPP ve PP/PA/EVOH/PE) ile ambalajlanmış ve 4°C’de 60 gün süreyle depolanmıştır. Depolama süresince tepe boşluğu gaz oranları (%O2 ve CO2), fizikokimyasal ve duyusal analizler yapılmıştır. Depolama süresince ambalajlı uygulamalarda ürün beyazlığı ve tekstür daha iyi korunmuş, duyusal nitelikler kabul edilebilir bulunmuştur. Tüm uygulamaların titrasyon asitliği ve TBARS değerleri artmış ve pH değerleri azalmıştır. Ancak depolama boyunca en iyi sonuçlar gaz geçirgenliği en düşük olan PP/PA/EVOH/PE’de vakum uygulamasında ve yüksek karbondioksitli MAP uygulamalarında alınmıştır. Sonuç olarak, ambalajsız üründe raf ömrü 5 gün, ambalajlı peynirlerde raf ömrü 60 gün olarak önerilmektedir.Öğe MICROBIAL, PHYSICAL, CHEMICAL AND SENSORY QUALITIES OF MINIMALLY PROCESSED AND MODIFIED ATMOSPHERE PACKAGED READY TO EAT ORANGE SEGMENTS(Taylor & Francis Inc, 2010) Karacay, Emel; Ayhan, ZehraOranges were sanitized, dried, peeled and segmented. Undamaged segments were packed under passive and active MAP with low and high oxygen in PP trays sealed with CPP/OPP film. Overall quality of the segments were monitored for 25 days at 4 degrees C. The results showed that orange segments could be stored under passive and active MAP without significant microbial growth. There were slight changes in acidity and Brix (p <= 0.05) with no significant changes in pH and sugar. The hardness increased and color ( L, a, b) decreased during storage. Orange segments remained in a commercially viable condition for 10 days under MAP.Öğe Modified Atmosphere Packaging of Kabaasi Apricot (Prunus armeniaca L. 'Kabaasi'): Effect of Atmosphere, Packaging Material Type and Coating on the Physicochemical Properties and Sensory Quality(Springer, 2012) Muftuoglu, Fatin; Ayhan, Zehra; Esturk, OkanEffects of modified atmosphere, packaging material and coating on the physicochemical properties and sensory quality of 'KabaaAYA +/-' apricot were studied. Apricots were coated with 5% NatureSealA (R), packaged under active (5% oxygen, 10% carbon dioxide) or passive atmospheres using polypropylene trays sealed with cast polypropylene or biaxially oriented polypropylene and stored at 4 A degrees C for 42 days. The colour values (L*, C* and HA degrees) significantly decreased after 28 days of storage at all applications (P a parts per thousand currency signaEuro parts per thousand 0.05). For packaged fruit, mass loss was less than 1%; however, unpackaged apricots lost 57% of their initial fresh mass until the end of storage. In general packaging material, atmosphere and coating had no significant effect on chemical attributes (pH, antioxidant activity and total carotenoid content). Physicochemical characteristics and sensory quality of uncoated and coated apricots were preserved for 28 days under active or passive modified atmosphere packaging using biaxially oriented polypropylene or cast polypropylene film. However, shelf life of unpackaged fruits was limited to less than 7 days.Öğe Modified Atmosphere Packaging of Napoleon Cherry: Effect of Packaging Material and Storage Time on Physical, Chemical, and Sensory Quality(Springer, 2012) Esturk, Okan; Ayhan, Zehra; Ustunel, Mehmet AliEffects of modified atmosphere and polymeric packaging material on the physical (mass loss, color, firmness), chemical (pH, total titratable acidity, total soluble solid, total phenolic content, total anthocyanin content), and sensory quality of Napoleon cherry (Prunus avium L. Napoleon) were studied. While lightness (L*) remained fairly unchanged, redness (a*), yellowness (b*), and chroma (C*) decreased during a 42-day storage period, resulting in darker fruit. Firmness did not differ significantly from the initial values (P a parts per thousand currency signaEuro parts per thousand 0.05) after 42 days of storage at 0A degrees C. pH increased for all treatments over the storage period. In general, total titratable acidity increased during the first 2 weeks, and then decreased afterwards. Packaging significantly reduced mass losses, which were 24.08%, 0.50%, 0.39%, and 0.81% for control (unpackaged), polypropylene tray/biaxially oriented polypropylene film (PP/BOPP), polypropylene tray/cast polypropylene film, and polyvinyl chloride-polyethylene tray/polyethylene terephthalate-polyethylene films, respectively. Modified atmosphere packaging was found beneficial on extending the shelf life of fruit during storage. The shelf life of Napoleon cherries was suggested as 28 days for packaged samples and 14 days for unpackaged samples at 0A degrees C. Samples packaged with PP/BOPP under 21% O-2 79% N-2 preserved their physical, chemical, and sensory quality better than other treatments.Öğe Overall Quality and Shelf Life of Minimally Processed and Modified Atmosphere Packaged Ready-to-Eat Pomegranate Arils(Wiley, 2009) Ayhan, Zehra; Esturk, OkanMinimally processed ready-to-eat pomegranate arils have become popular due to their convenience, high value, unique sensory characteristics, and health benefits. The objective of this study was to monitor quality parameters and to extend the shelf life of ready-to-eat pomegranate arils packaged with modified atmospheres. Minimally processed pomegranate arils were packed in PP trays sealed with BOPP film under 4 atmospheres including low and super atmospheric oxygen. Packaged arils were stored at 5 degrees C for 18 d and monitored for internal atmosphere and quality attributes. Atmosphere equilibrium was reached for all MAP applications except for high oxygen. As a general trend, slight or no significant change was detected in chemical and physical attributes of pomegranate arils during cold storage. The aerobic mesophilic bacteria were in the range of 2.30 to 4.51 log CFU/g at the end of the storage, which did not affect the sensory quality. Overall, the pomegranate arils packed with air, nitrogen, and enriched oxygen kept quality attributes and were acceptable to sensory panelists on day 18; however, marketability period was limited to 15 d for the low oxygen atmosphere. PP trays sealed with BOPP film combined with either passive or active modified atmospheres and storage at 5 degrees C provided commercially acceptable arils for 18 d with high quality and convenience.Öğe Pesticide residue analysis in parsley, lettuce and spinach by LC-MS/MS(Springer India, 2014) Esturk, Okan; Yakar, Yasin; Ayhan, ZehraIn this study, pesticide residues in parsley, lettuce and spinach (120 samples) were analyzed by the application of liquid chromatography-tandem mass spectrometry (LC-MS/MS). All samples of spinach, parsley or lettuce contained residues of three or more active substances. In parsley, carbendazim (100.0%), dichlorvos (100.0%), fenarimol (40.0%), pendimethalin (95.0%), in lettuce, diazinon (30.0%), dichlorvos (100.0%), pendimethalin (92.5%) phenthoate (12.5%), and in spinach, carbendazim (45.0%), cymoxanil (85.0%), dichlorvos (100.0%) and fenarimol (85.0%) were the significant active compounds. The maximum residue limits were exceeded in 28, 20 and 40 samples of parsley, lettuce and spinach, respectively. The results showed that there was a high occurrence of pesticide residues in parsley, lettuce and spinach samples from Hatay province, in which most of them were prohibited from use in Turkey for these vegetables. The contamination levels of these residues may be considered a serious public health problem according to the maximum residue limits (MRLs) of Turkey and the European Union (EU).Öğe Physiological physical chemical characteristics and sensory evaluation of minimally processed Grapefruit segments packaged under modified atmosphere(2010) Karaçay, Emel; Ayhan, ZehraThe objective of this study was to investigate physiological, physical, chemical, and sensory characteristics of minimally processed and modified-atmosphere-packaged grapefruit segments. Grapefruits were sanitized, peeled, segmented and packed under passive (21%$O _2$ +79% $N _2$) and two active modified atmospheres (20% $O _2$+10% C$O _2$ +70% $N _2$ and 70% $O _2$+20% C$O _2$ +10% $N _2$) in polypropylene trays. Physiological, physical, chemical, and sensory properties were monitored at 4 ºC for 15 days. In general, there was no significant effect of MAP observed in chemical properties (P > 0.05). There was no significant effect of MAP treatment on a* and b* values (P > 0.05); however, the firmness values increased at all applications (P $\leq$ 0.05). Grapefruit segments remained viable for 10 days under enriched oxygen (70%) and less than 10 days under active (20% oxygen) and passive MAP applications considering internal atmosphere and quality parameters. These results suggested that grapefruits could be prepared as ready to eat fruits with considerable shelf life, quality and convenience with using enriched oxygen MAP.Öğe Potential application of nanomaterials in food packaging and interactions of nanomaterials with food(CRC Press, 2013) Ayhan, ZehraNanotechnology has potential applications in all aspects of food chain including food processing, food quality monitoring, food packaging, and storage. Major areas of food industry that could benefit from nanotechnology are development of new functional materials for food packaging, microscale and nanoscale processing, product development, and methods and instrumentation design for improved food safety and biosecurity. © 2013 by Taylor & Francis Group, LLC.Öğe Production and Application of Active Packaging Film with Ethylene Adsorber to Increase the Shelf Life of Broccoli (Brassica oleracea L. var. Italica)(Wiley-Blackwell, 2014) Esturk, Okan; Ayhan, Zehra; Gokkurt, TolgaBroccoli (Brassica oleracea L. var. Italica) florets were packaged in low-density polyethylene (LDPE) bags with or without ethylene adsorber under passive modified atmosphere and then stored at 4 degrees C for 20days. LDPE films with (8% Tazetut (R) masterbatch, M2) or without ethylene adsorber (M1) were tested. The effects of modified atmosphere packaging treatments on gas concentrations (O-2, CO2 and ethylene) in the headspace, the mass loss, colour, texture, pH, total soluble solids, chlorophyll content, total phenolic content and sensory quality of packaged broccoli were determined by comparing with unpackaged (control) florets. Results revealed that deterioration occurred quickly in control broccoli, manifested mainly by mass loss, chlorophyll degradation and stem hardening. Also, it was found unacceptable by sensory panel after 5days. Conversely, in those florets packaged under modified atmosphere packaging, especially for LDPE with ethylene adsorber (M2), all changes related with loss of quality were significantly reduced and delayed with time. Additionally, total soluble solids and total phenolic content remained almost unchanged during the whole period. Ethylene concentration was determined as 61.8ppm in M1 and 0.33ppm in M2, respectively, at the end of the storage. Thus, broccoli packaged with M2 films had prolonged storability up to 20days with high quality attributes, this period being only 5days in unpackaged control broccoli. Oxygen concentration decreased below 1% after 5days of storage in M1, and the shelf life of broccoli in these bags was limited to 5days because of risk for anaerobic fermentation. Copyright (c) 2013 John Wiley & Sons, Ltd.
