Quality changes of spotless shad during storage at different conditions

KORAL, SERKAN/0000-0001-7424-2481; Kose, Sevim/0000-0001-6029-0458WOS: 000377012900006This study investigates the effect of using ice in combination with refrigeration on the sensory, physico-chemical and microbiological attributes of spotless shad during storage. Spotless shad kept in ice under refrigerated conditions had better sensory, physicochemical and microbiological quality as compared with control groups. the shelf life of samples kept at ambient temperature without ice was 2 days. Using ice and refrigeration only extended the shelf-life for 3 days and 4 days, respectively, while ice application with refrigeration further increased the shelf-life by 10 days. Physico-chemical and microbiological results usually supported sensory values. Histamine values were below EU (European Union) and FDA permitted levels for the shelf-life of fish

Sıcak tütsülenmiş kültür ve doğal istavritin (trachurus mediterraneus, steindachner, 1868) donmuş muhafaza (-20±2°C) koşullarındaki kalite değişimleri ve raf ömrü

Tütsüleme dünyada hem balık hem de et ürünlerinde kullanılan geleneksel bir koruma yöntemidir. Günümüzde tütsülenmiş balıklar kendilerine özgü tat ve aromanın yanı sıra uzun raf ömrüne sahip olmalarından dolayı da çokça rağbet görmektedirler. Bu çalışmada, doğal ve kültüre edilmiş istavrit balıklarının sıcak tütsüleme yöntemiyle tütsülendikten sonra donmuş muhafaza (-20±2°C) koşullarında depolanmaları esnasındaki kalite değişimleri ve buna bağlı olarak raf ömürlerinin karşılaştırmalı olarak tespit edilmesi amaçlanmıştır. Balıkların iç organları temizlenip yıkanmış, daha sonra %10'luk tuz salamurası ile 1 saat boyunca bekletildikten sonra sıcak tütsüleme işlemi uygulanmıştır. Örnekler strafor tabaklara dizilip üzerleri streç film ile kaplanmış ve -40?C'de 24 saat şoklandıktan sonra donmuş muhafaza koşullarında (-20±2°C) depolanmışlardır. Ürünlerdeki kalite değişimine bağlı raf ömrünün tespiti için aylık olarak kimyasal, mikrobiyolojik ve duyusal analizler yapılmıştır. Toplam Uçucu Bazik Azot (TVB-N), Tiyobarbitürik Asit (TBA) ve Trimetilamin (TMA) analizi sonuçlarına göre her iki grup da kabul edilebilir sınırlar içerisinde kalmıştır. Her iki grubun da histamin miktarları hem Amerikan Gıda ve İlaç Dairesi hem de Avrupa Birliği kuruluşlarının izin verdiği değerlerin altında bulunmuştur. Duyusal analiz sonuçlarına göre her iki grubun da 7 aylık raf ömrüne sahip olduğu tespit edilmiştir. Bu çalışma, sıcak tütsülenmiş doğal ve kültür istavrit balıklarının donmuş muhafaza koşullarında 7 ay süreyle depolanabileceğini göstermiştir. Kimyasal ve mikrobiyolojik kalite parametrelerinde her iki grupta da istatistiki olarak önemli değişimler gözlenmesine rağmen (P<0,05), duyusal değerlendirmede önemli bir farka rastlanmamıştır. Bununla beraber, kültür örneklerinin tüketici beğenisinin daha iyi olması bu türün kültüre edilmesinin daha iyi pazar değeri olacağına işaret edebilir. Ayrıca bu çalışmada biyojenik amin gelişiminin yavaşladığı gözlemlendiği için, bu tür örneklerde donmuş depolama sayesinde histaminden kaynaklı sağlık riski azalacaktırSmoking is a traditional preserving method used for both fish and meat products around the world. Smoked fish products have wide acceptance today due to their accustomed taste and aroma as well as their extended shelf-life. In this study, we aimed to determine quality changes and shelf-life of wild hot-smoked Mediterranean horse mackerel (Trachurus mediterraneus, Steindachner, 1868) during frozen storage (-20±2ºC) in comparison with its cultured counterparts. After gutting, cleaning and draining the samples, they were salted in 10% brine solution for 1 h and hot smoked within the same day. The samples were placed in styrofoam plates covered with a stretched film and frozen at -40?C for 24 h. Then, all samples were stored at -20±2ºC until spoilage. Chemical, microbiological and sensory analyses were performed monthly to investigate their quality changes and the shelf stability of the products. The results of total volatile basic-nitrogen, thiobarbituric acid and trimethylamine were obtained within the acceptable levels. Histamine values were found well below the permitted limits set by Food and Drug Administration and European Union. Sensory results showed that both storage groups (wild and cultured) had 7 months of shelf-life. This study showed that hot-smoked wild and cultured horse mackerel can be stored at -20±2ºC for 7 months. Culturing did not make any significant differences (P<0.05) in sensory quality despite of differences in chemical and microbiological changes between wild and cultured groups during storage. On the other hand, better consumer acceptance was observed for cultured samples indicating the advantage of culturing this species for a better market value. We also observed that frozen storage can retard the formation of biogenic amine contents and therefore, it is suggested to apply for such products to avoid histamine health ris

EVALUATION OF BIOGENIC AMINE DEVELOPMENT OF ANCHOVY (Engraulis encrasicolus) MUSCLE COMPARED TO ITS QUALITY CHANGES AT DIFFERENT CHILLING CONDITIONS

This study investigates biogenic amine development (BA) vs. sensory, chemical and microbiological quality loss of anchovy (Engraulis encrasicolus) at three different chilled storage conditions which are commonly applied for fresh market and/storage prior to processing. The contents of BAs and sensory, chemical and microbiological quality parameters of anchovy were analysed daily during storage. Significant variations occurred (p<0.05) in the sensory, chemical and microbiological values among the storage groups. The highest shelf-life was found as 8 days for samples kept in chilled freshwater. Water-ice mix application resulted in lower TBA content indicating beneficial effect on its quality. Histamine results closely supported sensory values in terms of legally permitted levels set by US Food and Drug Administration (FDA). Histamine forming bacteria counts supported the formation of histamine in most groups while total bacteria counts were in agreement with sensory results in terms of acceptability. Moreover, some existing formulated indexes created from various BA levels were not found suitable to estimate spoilage degree of anchovy kept at these conditions. This study suggests that using ice and water-ice mix can improve shelf-life of anchovy stored at refrigerated temperatures in terms of food quality and safety. The results of this study can be used to guide seafood industry for testing fresh anchovy quality and safety at different chilled conditions

Hamsinin (Engraulis encrasicolus, L. 1758) Farklı Depolama Sıcaklıklarındaki Kalite Değişimleri Üzerine Bir Araştırma

Quality changes in anchovy caught at different times during storage at ambient and refrigerated temperatures were investigated in 3 different batches. Sampling was carried out each day during storage. The results showed no significant differences among the anchovy batches except for bacteriological counts and trimethylamine (TMA) values at refrigerated temperatures. Storage time and temperature had a significant effect (P < 0.001, P < 0.05) on sensory, bacteriological and chemical values. Bacteriological counts and chemical values increased significantly (P < 0.05, P < 0.001) depending on time, while sensory results decreased (P < 0.05). According to sensory results, samples were acceptable for 1 day at ambient temperatures and for 2 days refrigerated. This study showed that refrigeration did not extend the shelf-life of fresh anchovies by more than a day compare to ambient temperature.Hamsinin oda sıcaklığı ve buzdolabı koşullarında depolanması esnasındaki kalite değişimleri farklı zamanda avlanan üç grup örnekle incelendi. Depolama esnasında günlük örnekleme yapıldı. Araştırma sonuçları üç grup arasında, buzdolabı koşullarında depolanan örneklerde bakteriyolojik ve TMA değerleri haricinde önemli bir farklılık bulunmadığını gösterdi. Ancak, tüm örneklerde elde edilen duyusal, bakteriyolojik ve kimyasal değerlerde depolama sıcaklığı ve zamanına bağımlı olarak önemli ölçüde değişim olduğu saptandı (P < 0.001, P < 0.05). Bakteri sayısı ve kimyasal değerler zamana bağımlı olarak artış gösterirken (P < 0.05, P < 0.001), duyusal değerlerde önemli derecede azalma gözlendi (P < 0.05). Duyusal analizlere göre hamsinin raf ömrü oda sıcaklığında bir gün, buzdolabında ise iki gün olmuştur. Böylece, buzdolabı koşullarında ürünün raf ömrünün oda sıcaklığına göre sadece bir gün uzatılabildiği tespit edilmiştir

Quality changes and shelf life of cultured and wild hot-smoked mediterranean horse mackerel (Trachurus mediterraneus) at refrigerated (4 +/- 1 degrees C) conditions

TUFAN, BEKIR/0000-0001-7039-308X; Kose, Sevim/0000-0001-6029-0458; KORAL, SERKAN/0000-0001-7424-2481WOS: 000389702300005Mariculturing of horse mackerel is not known in the world. Additionally, limited studies exist on quality changes of smoked horse mackerel at refrigerated temperatures. Therefore, in this study, between 1+ and 2-year-old wild and cultured horse mackerels were hot smoked and stored at refrigerated conditions. Chemical, microbiological, and sensory analyses were performed weekly to investigate quality changes and to determine the shelf stability of the products. the results of thiobarbituric acid, trimethylamine, and total bacteria counts were obtained within the acceptable levels. Although the counts of histamine-forming bacteria increased significantly (p < 0.05) during storage, histamine values were well below the permitted limits set by Food and Drug Administration and European Union (EU). Sensory results showed that both storage groups had 3 weeks of shelf life. Total volatile basic nitrogen values supported sensory results. Therefore, the results indicate that culturing of horse mackerel did not alter the quality during storage at 4 +/- 1 degrees C.Turkish governmentTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TAGEM-10/AR-GE/19]This study was funded by the Turkish government under the Project No. TAGEM-10/AR-GE/19

SFLA based PI parameter optimization for optimal controlling of a Buck converter's voltage

2017 International Artificial Intelligence and Data Processing Symposium (IDAP) -- SEP 16-17, 2017 -- Malatya, TURKEY -- IEEE Turkey Sect, Anatolian SciIn this work, it is aimed to control the output of Buck Converter which steps down a DC voltage level. Discrete Time PI Algorithm is chosen as control algorithm. The controller parameters of K-p and K-i is calculated by means of the optimization process to increase the efficiency of power transmission of Buck Converter instead of classical methods like Pole Placement Method. It is chosen Shuffled Frog Leaping Algorithm (SFLA) which is an iterative algorithm as optimization algorithm. The results obtained from simultaneous executions of control process is discussed by simulating in Matlab-Simulink.WOS:0004268687000722-s2.0-8503989657

Determination of biogenic amines in fresh fish and processed fish products using IC-MS/MS

A new method was proposed for the determination of underivatized biogenic amines based on ion-exchange chromatography coupled with mass spectrometry detection. The method was applied to the analysis of 10 biogenic amines in fresh and processed fish products. The amines were extracted from muscle tissue with water without any additional derivative step or sample clean-up. Separation of biogenic amines was done by the IonPac (4 × 50 mm) column, applying a gradient eluent by mixing formic acid (2 mol L$^{−1}$) and Milli-Q water (formic acid concentration from 400 mM to 2 M). The results demonstrated a linear response in the range of 0.01 to 10 mg L$^{−1}$. The detection limits for the fish products ranged from 20 ng/g up to around 400 ng/g for histamine and putrescine, respectively. Spermidine and spermine showed significantly higher detection limits. This current method can be used for the determination of biogenic amines in both fresh and processed fish products for regulatory purposes and monitoring food-safety issues relating to these amines, particularly histamine. It is also a useful method for evaluation of other commercial analytical test kits and commonly used methods that are possibly affected by the food matrix due to processing or other drawbacks arising from the derivatization process