Food Engineering / Gıda Mühendisliği

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  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Correlation of Low Field Nuclear Magnetic Resonance Relaxation With Composition and Glass Transition of Hard Candies
    (Frontiers Media S.A., 2024) Ozel, Baris; Berk, Berkay; Uguz, Sirvan Sultan; Grunin, Leonid; Oztop, Mecit Halil
    Hard candies produced from sucrose and doctoring agents such as glucose syrup (GS) and high fructose corn syrup (FS) have been investigated in terms of their final composition, glass transition temperature (Tg), degree of crystallinity, total soluble solids (TSS) content and water activity (aw). Time domain (TD) 1H NMR longitudinal relaxation time (T1) and second moment (M2) measurements have been used to understand the glassy state and crystallization characteristics for different hard candy formulations. The investigated candies include sucrose as the main sugar component. Different levels of doctoring agents have been mixed with sucrose to obtain products with different characteristics. It has been shown that addition of any doctoring agent to sucrose formulations decreases the Tg of the system significantly (p <= 0.05). Furthermore, GS or FS addition also induce significant changes in TSS and aw. T1 and M2 results are almost parallel to each other, both reaching the highest values for the highest sucrose concentration (p <= 0.05). The results demonstrate that the glass transition and crystallization characteristics of hard candy formulations can be monitored and analyzed by TD NMR relaxometry, alternative to other frequently used conventional methods including differential scanning calorimetry (DSC) and X-ray diffraction.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Exploring Noncentrifugal Sugar as a Partial Replacement for White Sugar in Low Methoxyl Pectin Confectionery Gels: Impacts on Physical and Rheological Properties
    (American Chemical Society, 2024) Fakhar, Hafiz Imran; Çavdaroğlu, Elif; Hayat, Muhammad Qasim; Janjua, Hussnain A.; Oztop, Mecit Halil
    Noncentrifugal sugar (NCS) is an unrefined, dark brown sugar containing minerals and plant secondary metabolites, unlike refined white sugar (WS). This study explored using NCS in confectionary jellies as an alternative sugar. We used different concentrations of NCS and WS to prepare low methoxyl pectin (LMP) confectionery gels characterized by their physical and rheological properties along with time-domain nuclear magnetic resonance (TD-NMR) relaxometry. The strongest LMP gel, with a hardness of 0.94 N, was achieved by substituting 25% of WS with NCS at a low CaCl2 concentration (0.075 M). Gels with up to 50% WS replaced by NCS showed comparable hardness to standard LMP gels made solely with WS at a 0.15 M CaCl2 concentration, attributed to NCS's unique constituents. The NCS-WS gel exhibited the shortest T2 values (139.8 ms) and self-diffusion coefficient values (4.99 x 10-10 m2/s), indicating a denser, more cross-linked structure that restricted water mobility. These findings suggest NCS's complex role in affecting LMP gels' chemical and physical properties, highlighting its potential as a partial WS replacement in LMP gelation-based products, with an additional source of minerals and antioxidants.
  • Review
    Citation - WoS: 41
    Citation - Scopus: 43
    Electrochemical Sensors in the Food Sector: a Review
    (American Chemical Society, 2024) Ghaani, Masoud; Azimzadeh, Mostafa; Büyüktaş, Duygu; Carullo, Daniele; Farris, Stefano
    In a world that is becoming increasingly concerned with health, safety, and the sustainability of food supply chains, the control and assurance of food quality have become of utmost importance. This review examines the application and potential of electrochemical sensors in the dynamic field of food science to meet these expanding demands. The article introduces electrochemical sensors and describes their operational mechanics and the components contributing to their function. A summary of the most prevalent electrochemical methods outlines the diverse food analysis techniques available. The review shifts to discussing the food science applications of these sensors, highlighting their crucial role in detecting compounds in food samples like meat, fish, juice, and milk for contemporary quality control. This paper showcases electrochemical sensors' utility in food analysis, underscoring their significance as powerful, efficient tools for maintaining food safety and how they could transform our approach to global food quality control and assurance.
  • Article
    Effect of Partial Replacement of Sucrose With Stevia and Sucralose on the Physicochemical and Structural-Mechanical Properties of Apple Marmalade
    (2024) Berk, Berkay; Şirin, Pınar; Ünlütürk, Sevcan
    In this study, low-sugar apple marmalade formulations were developed by partial replacement of sucrose with stevia and sucralose. Their rheological, textural, physicochemical properties and microstructures were evaluated. The concentration of sweeteners was found to have a significant effect on the physicochemical and rheological properties of the formulations. The hardness of marmalades decreased with addition of sweeteners. Herschel–Bulkley model was found to be the best model describing rheological behavior. The consistency index decreased with increasing sweeteners substitution, whereas the flow behavior index showed an increasing trend with the increase of the sweeteners content. Additionally, the microstructure of marmalades with sweetener substitution exhibited a porous structure in the gel network. The increase in sucralose concentration resulted in more surface deformation resulting in weaker gel formation than stevia. Marmalade prepared with 50% stevia substitution was found the best combination and resulted in good sensory properties like marmalade samples containing 500 g sugar.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 10
    An Efficient Method of Improving Essential Oil Retention and Sustained Release of Chitosan Films: Ultrasound-Assisted Preparation of Chitosan Composites With Surface Active Chickpea Proteins
    (Elsevier, 2024) Barış Kavur, Pelin; Yemenicioğlu, Ahmet
    This work aimed at preparing chitosan (CHI) composites with surface active chickpea protein (CP) showing better eugenol (EUG) retention and sustained release capacity than pristine CHI films. For this purpose, ionic complexation of CHI with CP (CHI:CP ratio = 2:1, w/w) in the presence of EUG at pH 5.0 was achieved using mechanical homogenization alone (HM) or in combination with ultrasonic homogenization (HM-HUS). The HM-HUS treatment provided better solubility of CP (4.4-fold), increased emulsified EUG in film-forming solutions, and denser films than HM treatment. The composite films obtained using HM-HUS (FLMCHI-CP-EUG/HM-HUS) retained 1.2–1.4-fold higher EUG after drying, and showed almost 2-fold slower EUG release in air at room temperature than composite films prepared by HM, and control CHI films prepared by HM (FLMCHI-EUG/HM) or HM-HUS (FLMCHI-EUG/HM-HUS). The FLMCHI-CP-EUG/HM-HUS films also showed better moisture barrier and mechanical properties than other films. The developed films were proved in a challenging coating application with onions. Escherichia coli and Listeria innocua counts of inoculated and FLMCHI-CP-EUG/HM-HUS (average coating thickness = 4.5 ± 1.3 μm) coated onions were significantly lower than those of uncoated (2.8 and 3.8 log) and FLMCHI/HM-HUS (1.4 and 1.3 log) coated onions after 5-days at room temperature. FLMCHI-CP-EUG/HM-HUS coating also reduced percentage of sprouted onions from 30 to 10% during storage. EUG odor of coated onions could not have been detected by 80% of panelists after 4 weeks. Compositing with CP boosts the performance of essential oil loaded CHI films by enabling use of film matrix as an encapsulant. © 2024 Elsevier Ltd
  • 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: 10
    Citation - Scopus: 11
    Enzymatic Hydrolysis of Organosolv-Pretreated Corncob and Succinic Acid Production by Actinobacillus Succinogenes
    (Elsevier, 2024) Buyukoztekin, Gulperi Karanfil; Buyukkileci, Ali Oguz
    In this study, the conversion of organosolv-treated corncob into monosaccharides through enzymatic sacchari-fication was investigated, with the resulting monosaccharides being utilized as a carbon source to produce succinic acid. The synergy between the cellulase and xylanase provided 76% cellulose and 64% xylan di-gestibility at 50 degrees C and pH 5.2. In separate hydrolysis and fermentation (SHF), Actinobacillus succinogenes pro-duced 12.7 g/L of succinic acid from the hydrolysate with 0.12 g/g yield based on the pretreated corncob. Simultaneous saccharification and fermentation (SSF) demonstrated better performance with 16 g/L succinic acid titer and 0.24 g/g yield, though SHF provided a higher production rate. The condition in the SSF (37 degrees C and pH near neutral) was suboptimal for the enzymes, thus the succinic acid production was limited by the saccharification step. These findings emphasize the potential of organosolv-treated corncob to serve as an enzymatic hydrolysis substrate without neutralization and detoxification, supplying glucose and xylose for succinic acid production by A. succinogenes.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 7
    Acid-Derived Bacterial Cellulose Nanocrystals as Organic Filler for the Generation of High-Oxygen Barrier Bio-Nanocomposite Coatings
    (Royal Soc Chemistry, 2023) Carullo, Daniele; Rovera, Cesare; Bellesia, Tommaso; Büyüktaş, Duygu; Ghaani, Masoud; Santo, Nadia; Farris, Stefano
    Macro-sized bacterial cellulose (BC) derived from Komagataeibacter sucrofermentans was down-sized into nanocrystals (BCNCs) through hydrochloric acid (H-BCNCs) and sulfuric acid (S-BCNCs) hydrolysis. Initially, aqueous dispersions of BCNCs were analyzed for stability, size/morphology, and optical/mechanical properties. Subsequently, BCNCs were incorporated into a main biopolymer phase (i.e., pullulan) to create bio-nanocomposite coatings with high-oxygen barrier performance. Upon treatment with sulfuric acid, nano-sized particles (approximate to 240 nm) were observed, contrasting with significantly larger sizes (approximate to 1.8 mu m) seen for particles obtained using hydrochloric acid. Microscopy analyses revealed a needle-like morphology of the nanocrystals, which appeared organized in stacks for H-BCNCs or as individual units for S-BCNCs. Pullulan/BCNCs coatings applied to polyethylene-terephthalate (PET) films improved the gas barrier performance of the original substrate, by dramatically reducing the oxygen transmission rate (OTR) values from approximate to 120 cm3 m-2 24 h-1 to approximate to 2 cm3 m-2 24 h-1 while preserving its original optical and mechanical properties. Our developed bionanocomposite-coated PET films hold potential as an alternative material for various food packaging applications. This study investigates the effect of the hydrolysis process on bacterial cellulose (BC) to obtain bacterial cellulose nanocrystals (BCNCs) used to create high oxygen barrier nanocomposite coatings for food packaging applications.
  • Article
    Citation - Scopus: 11
    Chemical Composition and Biological Activities of Cypriot Propolis
    (Taylor and Francis Ltd., 2022) Nalbantsoy, A.; Sarıkahya, N.B.; Özverel, C.S.; Barlas, A.B.; Kırcı, D.; Akgün, İ.H.; Yalçın, Tansel; Düven, Gamze
    Propolis compositions are highly variable, depending on the geographic region and the season of collection. In this study, propolis samples from seven different regions of Cyprus were studied for the first time by means of chemical content and biological activities. Secondary metabolite composition was determined by LC-HRMS. While the major flavonoids found were isosakuranetin, naringenin, rhamnocitrin, diosmetin, chrysin and acacetin, interestingly verbascoside, a phenylethanoid glycoside, and chlorogenic acid were identified as the major compounds in the ethanol-water extracts. α-Pinene was detected as the major compound of propolis extracts according to the volatile compositions via GC-MS. Karaoglanoglu and Tirmen extracts, presenting different chemical profiles, exerted enormous cytotoxic activity by MTT assay (IC50: 2.36–11.56 µg/mL; 1.44–9.33 µg/mL, respectively). The highest iNOS inhibition potential was detected in the Karpaz extract (IC50:2.6 µg/mL) in LPS induced RAW 264.7 cells whereas the Guzelyurt sample demonstrated remarkable antioxidant (88.82 ± 0.10%) and antimicrobial activities (with a MIC value of 31.2 μg/mL against S. aureus, S. epidermidis, E. faecium, and E. faecalis). © 2021 International Bee Research Association.
  • 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.