Food Engineering / Gıda Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/12

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  • Article
    Citation - WoS: 17
    Citation - Scopus: 18
    Incorporation of Organic Acids Turns Classically Brittle Zein Films into Flexible Antimicrobial Packaging Materials
    (Wiley, 2022) Sozbilen, G.S.; Çavdaroğlu, E.; Yemenicioglu, A.
    This study aimed to turn classically brittle zein films into flexible antimicrobial ones by the use of lactic (LA), malic (MA) and tartaric acids (TA). The most effective plasticizer was LA (400% elongation at break [EB] at 4%), while MA (189% EB at 4.5%) and TA (68% EB at 5%) showed moderate and limited plasticizing effects, respectively. The LA- and MA-loaded films maintained their flexibility during 30-day storage at 4°C or 25°C. Fourier transform infrared (FTIR) analysis suggested that the plasticization of LA and MA could be related to secondary structural changes in zein such as increased α-helix and random coils (mainly by MA) and spaced/modified intermolecular (only by LA) and intramolecular (mainly by MA) β-sheets. Atomic force and scanning electron microscopy showed that LA and MA gave more homogenous and smoother films than TA. Films with LA showed the highest water vapour permeability followed by those of control, MA- and TA-loaded films. Films with 3%–4% LA or MA formed clear zones on Listeria innocua and Klebsiella pneumonia, but only films with LA formed clear zones on Escherichia coli. All OA-loaded films gave unclear zones on Staphylococcus aureus in disc-diffusion tests, but this bacterium was inactivated rapidly in antimicrobial tests based on surface inoculation tests. LA is the best OA to develop flexible antimicrobial films from zein, an industrial by-product that films could not have been utilized as a widespread packaging material due to their brittleness. © 2021 John Wiley & Sons, Ltd.
  • Article
    Citation - WoS: 34
    Citation - Scopus: 32
    Lymphedema After Sentinel Lymph Node Biopsy: Who Is at Risk
    (Mary Ann Liebert, Inc., 2022) Isik, A.; Soran, A.; Grasi, A.; Barry, N.; Sezgin, E.
    Background: Sentinel lymph node biopsy (SLNB) is the accepted approach to stage the clinically negative axilla. The incidence of lymphedema (LE) after SLNB is about 5%. We hypothesize that patients undergoing axillary excision of >5 lymph nodes (LNs) are at increased risk of developing LE. Methods and Results: A single institution prospective breast cancer database was retrospectively reviewed from January 2013 to December 2017, to identify patients who underwent SLNB and were diagnosed with LE. Inclusion criteria was (1) de novo breast cancer, (2) SLNB in clinically node negative patients, and (3) no preoperative diagnosis LE of an extremity. Exclusion criteria was history of axillary lymph node dissection. Age, body mass index, tumor-node-metastasis status, surgery type, neoadjuvant or adjuvant chemotherapy, radiotherapy, and hormone therapy were analyzed. Of the 3325 patients identified, 2940 patients met the inclusion criteria and were included in the final analysis. Median follow-up time was 24 months. Forty-seven (2%) patients were diagnosed with LE, and nine patients (19%) had >5 LNs excised. LE was diagnosed in 3.7% of patients who had >5 LNs excised versus 1.4% of patients with ≤5 LNs excised. Incidence of LE was higher in patients with >5 LNs excision (p = 0.006). Conclusion: Our study showed that patients have a higher likelihood of developing LE when >5 LNs are excised. © Copyright 2022, Mary Ann Liebert, Inc., publishers 2022.
  • Book Part
    Citation - Scopus: 1
    Enzyme Production From Sourdough
    (CRC Press, 2023) Elvan, Menşure; Harsa, Şebnem
    Sourdough is a traditional fermented food well known around the world. It contains a wide variety of components, such as cereals and pseudocereals, and is rich in microflora that can potentially be used for enzyme production. Sourdough is a good source of lactic acid bacteria that have high enzyme production capability. Enzymes have different roles during sourdough fermentation: mainly, amylase and xylanase enzymes have important effects in improving texture; protease and phytase enzymes increase the nutritional value of sourdough; lipoxygenase improves the shelf life of products; and esterase plays a leading role in aroma and flavor formation. Additionally, it is possible to isolate sourdough enzymes for their potential to improve the health attributes of other foods, i.e., enzymes to break down gluten, hydrolyze phytic acid, and degrade fructans. Moreover, these enzymes may also be used to improve the technological properties of grain-based foods and beverages. Currently, there are no studies on the large-scale production of enzymes based on sourdough, although microorganisms isolated from sourdough have the potential for industrial-scale food applications as the sourdough microflora and derived enzymes have Generally Recognized as Safe (GRAS) and green label status. This chapter reviews sourdough enzymes and their importance for improving the quality and shelf life of foods in different food industries and products. © 2024 selection and editorial matter, Marco Garcia-Vaquero and João Miguel F. Rocha.
  • Book Part
    Discovery, Characterization, and Databases of Enzymes From Sourdough
    (CRC Press, 2023) Ağırbaşlı, Zeynep; Harsa, Şebnem
    Sourdough enzymes have not been investigated in wide scale yet. Therefore, this chapter summarizes the main strategies and techniques used for the identification of sourdough enzymes together with the compilation of this information in databases for a wide variety of applications. The chapter describes a panel of methods based on different approaches, such as biochemical and molecular techniques for the identification of several key microbial enzymes emerged from sourdough or a combination thereof. Review includes information on the enzymes in carbohydrate metabolism, protein metabolism, phenolic metabolism, and stress metabolism together with enzymatic formation of bioactive compounds in sourdough. © 2024 selection and editorial matter, Marco Garcia-Vaquero and João Miguel F. Rocha.
  • Book Part
    Citation - Scopus: 1
    Enzyme Technology in Value Addition of Wine and Beer Processing
    (Elsevier, 2022) Uzuner, Sibel
    Some endogeneous and exogeneous enzymes participate in the brewery and winery technologies. Industrial enzymes provide quantitative advantages (increased juice yields) and qualitative advantages (enhanced extraction and flavor) for processing (shorter maceration, settling, and filtration time). This review aims to explain the flow process of brewing and wine-making, discuss different enzymes used in brewery and wine-making industry. Also, this chapter summarizes the key enzymes used at different stages of wine-making and brewing, and the challenges of the exogeneous, commercial and immobilized enzymes. Finally, the use of immobilized enzymes is presented as a significant strategy to improve catalyst during brewing and wine-making.
  • Book
    Citation - Scopus: 15
    Edible Food Packaging With Natural Hydrocolloids and Active Agents
    (CRC Press, 2022) Yemenicioğlu, Ahmet
    The aim of this book is to show the potential of natural hydrocolloids and active agents to develop sustainable edible packaging materials for food preservation. For this, the current and future sources of natural hydrocolloids have been reviewed along with their extraction methods, impact on health and ability to form different packaging such as film, casing, coating, mat, pad, etc. Similarly, natural active compounds were evaluated carefully considering their sources, extraction methods, regulatory status, and compatibility with edible packaging. The book emphasizes the recent developments in methods, strategies and technologies employed to enhance the performance of antimicrobial, antioxidant and bioactive packaging. The basic testing methods used to evaluate antimicrobial and antioxidant activity of edible packaging in model media and food were discussed, and carefully selected example active edible packaging applications for different food categories were provided with critical details such as the thin balance between effectiveness of packaging and sensory properties of food. As such, it helps in understanding necessary parameters in designing an effective active edible packaging that is applicable to the target food category. Moreover, readers are primed for the first time on how to develop a fully natural antimicrobial, antioxidant or bioactive edible food packaging. This book is different from most of the similar books' avail as it provides neither methodologies about classical active packaging based on chemicals and fossil polymeric films nor is it a thorough collection of different food packaging applications. It is also not a book that concentrates on physicochemical characterization methods and engineering aspects of packaging. Instead, this is a book that provides systematic knowledge about key methods of evaluating natural resources, agro-industrial wastes and by-products for development of edible packaging, and concentrates on concepts, strategies, technologies, and applications of active edible packaging based solely on natural components. It is designed to share both positive and negative experiences in an emerging field that is expected to play a central role in improving food safety and quality, human health and environmentally friendly practices.
  • Book Part
    Citation - Scopus: 8
    Uv Processing and Storage of Liquid and Solid Foods: Quality, Microbial, Enzymatic, Nutritional, Organoleptic, Composition and Properties Effects
    (Elsevier, 2021) Hakgüder Taze, Bengi; Pelvan Akgün, Merve; Yıldız, Semanur; Kaya, Zehra; Ünlütürk, Sevcan
    Non-thermal food processing technologies have been explored extensively in recent years in order to develop food products with extended shelf life as well as preserved nutritional and organoleptic characteristics in accordance with the changing consumer demands (Falguera et al., 2011a; Sanchez-Moreno et al., 2009). Ultraviolet (UV) irradiation is one of the non-thermal processes that can be applied to reduce the microbial load in liquid foods and surfaces, and to sterilize food packages and packaging materials, and environments involved in food processes (Jimenez-Sanchez et al., 2017a; Bintsis et al., 2000). UV light is subdivided into three regions as short-wave UV (UV-C, 200 and 280 nm), medium-wave UV (UV-B, 280 to 315 nm), and long wave UV (UV-A, 315 to 400 nm). The different types of effects on microorganisms can be caused by UV light of different wavelengths. The effectiveness of UV light on microorganisms results primarily from the fact that DNA molecules absorb UV photons between 200 and 300 nm, with peak absorption around 260–265 nm. This causes DNA damage by altering the nucleotide base pairing, thereby creating new linkages between adjacent nucleotides, particularly between pyrimidine bases, on the same DNA strand and ultimately results in cell death (Zimmer and Slawson, 2002). Peak et al. (1984) proposed that the dimer formation is not the only requirement to damage the DNA. Absorption of different wavelength photons by different molecular groups in the long DNA molecule can damage or destroy these bond groups. Thus, different bonds in the DNA can be affected with photons of different energy (Neister, 2014).
  • Conference Object
    Photoautotrophic and Heterotrophic Micropropagation of Sugarcane Shoots in Controlled Environments
    (2000) Ertürk, Handan; Walker, Paul N.
    We achieved successful growth and multiplication of sugarcane shoots in vitro under photoautotrophic conditions aseptically for three generations in our laboratory and proposed an experimental procedure for photoautotrophic micropropagation of sugarcane in controlled environment. The growth rate of photoautotrophic cultures in sugarless MS medium was found to be half of the growth rate of heterotrophic cultures in multiplication medium after a two-week period in the same environment. Contamination with algae in some vessels was recognized as a problem for septic photoautotrophic growth. Atrazine was found to be effective in controlling algae at a concentration of 10 ppm. But, atrazine in total was not considered to be a practical solution for the algae problem as it had a negative affect on the growth of shoots.
  • Book Part
    Citation - Scopus: 4
    Bacteria: Arcobacter
    (Elsevier, 2014) Atabay, Halil İbrahim; Corry, Janet E.L.; Ceylan, Çağatay
    The genus Arcobacter currently comprises many phenotypically different species isolated from diverse niches. Although some Arcobacter spp. (particularly, Arcobacter butzleri, Arcobacter skirrowii, and Arcobacter cryaerophilus) are associated with various diseases in humans and animals, their exact epidemiological and pathological role is not completely understood, and few cases of human infection are reported. The primary mode of Arcobacter transmission is thought to occur via contaminated water and food and contact with pets. As some species are difficult to cultivate and all are difficult to identify using conventional biochemical tests, nucleic acid-based techniques such as polymerase chain reaction (PCR) and real-time PCR are increasingly used for their simultaneous detection, identification, and quantification. Their tendency to be resistant to antibiotics, and their ability to colonize food processing environments indicate that they could cause serious disease in the human population, particularly in susceptible individuals with impaired immune response. © 2014 Elsevier Inc. All rights reserved.
  • Book Part
    Citation - Scopus: 6
    Quality Assessment of Aquatic Foods by Machine Vision, Electronic Nose, and Electronic Tongue
    (Wiley, 2010) Korel, Figen; Balaban, Murat Ömer
    The increase in demand for seafood products has catalyzed the desire for higher standards regarding safety and quality issues. Since seafoods are perishable, freshness is a major quality parameter to be considered [1,2]. There is no unique freshness or spoilage indicator for seafood, therefore combinations of selected indicators need to be used to evaluate freshness [3,4]. An important and widely used method to determine freshness is sensory evaluation [5]. The Quality Index Method (QIM) uses a demerit point scoring system [6] based on the evaluation of the important sensory attributes (odour, texture, and appearance) of fish and other aquatic foods. The sensory quality is expressed by the sum of the demerit points, and a linear correlation between these points and the storage time is used to predict the freshness of the target seafood [5,7,8]. The QIM has been developed for various seafood species and products, such as Atlantic mackerel (Scomber scombrus), horse mackerel (Trachurus trachurus), European sardine (Sardina pilchardus) [9], gilthead seabream (Sparus aurata) [10], farmed Atlantic salmon (Salmo salar) [11,12], and cod (Gadus morhua) [13], etc. Even though QIM is fast and reliable in determining the freshness of seafood, it still requires experts to evaluate the quality attributes. Alternatively, appearance, odour, and taste can be measured by machine vision system (MVS), electronic nose (e-nose), and electronic tongue (e-tongue), respectively.