KEEPING QUALITY OF DIFFERENT PACKAGED SALTED ATLANTIC BONITO "LAKERDA"

Quality and shelf life of salted Atlantic bonito (lakerda) packaged in brine, under vacuum and in oil conditions and stored at 4  ±  1C were studied. The sensory scores of lakerda stored in all package types at 4C were 14 weeks, respectively. The microbiological count of the vacuum-packaged lakerda was extended than that lower of other group sample. Overall results of this study showed that 9 weeks of storage of lakerda in brine was the beginning of spoilage, whereas storage of samples in oil and vacuum package delayed onset of spoilage about 2–3 weeks in terms of chemical analysis. Lakerda stored in cold storage as sensory, chemical and microbiological results for brine- and oil-packaged lakerda showed us that week 11 was the beginning of spoilage, and for vacuum-packaged lakerda, week 13 was the beginning of spoilage.

PRACTICAL APPLICATIONS

Raw fish and processed fish product is highly perishable and has a short shelf life. Packing processing is finding increasing use in the food industry because of its relative advantages versus other food processing methods in eliciting minimal changes in the flavor, microbiological and nutritional qualities of the final product. This paper illustrates the changes induced in salted fish by packaging at different types. By using oil- and vacuum-packaged treatment, shelf life of traditional-packaged (in brine) lakerda could be extended at 4C from 9 weeks to 11–13 weeks.     

Efficiency of wave impeding barrier in pipeline construction under earthquake excitation using nonlinear finite element analysis

Earthquakes have caused colossal casualties and severe damages to engineering structures and especially leading to substantial economic loss to the underground structures and/or infrastructures. Pipelines are one of most important component of lifeline engineering. For instance, the Southern Caucasus- Eastern Turkey energy corridors are formed by several key pipelines carrying crude oil and natural gas from Azerbaijan, via Georgia, to world markets through Mediterranean Sea. Many project accomplished recently and construction of new corridors are still going on. They should be protected from earthquake disaster especially when they pass through high seismicity zones. The installation of wave impeding barriers (WIB) below the vulnerable infrastructures as pipelines established in soft soil can be used to reduce the effect of the earthquake induced ground borne vibrations. In this paper, a WIB as artificial bedrock based on the cut-off frequency of a soil layer over bedrock is proposed as isolation measurement in order to mitigate the dynamic response of the buried pipelines under earthquake strong ground motion. The computational simulation of the wave propagation problem is directly achieved by employing nonlinear 2D finite element modelling for prediction of screening performance of WIB on the dynamic response of vibrating coupled soil-pipeline system. Energy absorbing boundaries along the truncated interfaces of the unbounded nature of the underlying soil media are implemented in the time domain along with Newmark’s integration. An extensive parametric investigation and systematic computations are performed with different controlling parameters. The obtained numerical results point out that WIB can be very promising as an isolator to protect pipelines when they establish for a certain depth.     

CHANGES IN TOTAL PHENOLIC AND FLAVONOID CONTENTS OF ROWANBERRY FRUIT DURING POSTHARVEST STORAGE

ABSTRACT

Postharvest storage conditions of rowanberry (Sorbus aucuparia) fruits were investigated. The influences of temperature and storage time on total phenolic content were observed. Both variables affected phenolic content of rowanberries, and their total phenolic contents significantly reduced during the 20‐day storage at 4 and 22C. The loss of total phenolic was found to be almost 50% of its initial amount (3,619.8 mg/kg fresh weight [fw]) at 22C, which was higher than occurred loss (30%) at 4C. An investigation of rowanberry flavonoids showed the presence of rutin, quercetin‐3‐glucoside and quercetin‐3‐D‐galactoside (Q3DG). Quantitative analysis of berry flavonoids showed Q3DG as a major compound, being 24.55 mg/kg fw. The highest reduction (86% of its initial amount) was also seen in that compound level compared with other ones. Degradation kinetics of flavonoids was studied at 22C over 16 days of storage. Checking of model adequacies indicated that their reductions followed a first‐order kinetic.

PRACTICAL APPLICATIONS

Postharvest storage has been taken, increasing the interest of scientists because of various reasons, one of which is explained next. The presented results indicated the direct and/or indirect influence of storage conditions on the quality of berries, implying that whoever is planning to store plant and/or plant origin food products in a refrigerator or at room temperature should consider the conditions and their possible effects on the quality parameters from the aspects of economics and nutritional properties of products. In the present study, the stability of an important bioactive group, phenolics, in rowanberries and the influences of environmental conditions were examined, and additionally, degradation kinetics of major phenolic group, flavonoids, was analyzed. The results are valuable and helpful for the evaluation of the postharvest storage and its effect on rowanberries. Introduced model may be helpful for the prediction of storage time required for the degradation of phenolics up to the acceptable limit.     

SOME MICROBIOLOGICAL CHARACTERISTICS OF HERBED CHEESES

Fifty herbed cheese samples, in which herbs (Allium spp.) were used at production, were analyzed for some microbiological quality characteristics. Cheese samples were collected from different retailers in four counties of Eastern Turkey. Presumptive coliform bacteria, generic Escherichia coli, Staphylococcus aureus, lactic acid bacteria, yeast, mold and sulfite‐reducing anaerobic bacteria counts were examined as general microbiologic quality parameters, and the average bacteria counts were 2.1 × 10⁵, 3.1 × 10⁴, 1.1 × 10⁵, 2.2 × 10⁷, 6.8 × 10², 7.0 × 10⁶ and 3.2 × 10¹ cfu/g, respectively. The number of samples, in which the above selected bacteria have been detected, were 32 (64%), 29 (58%), 23 (46%), 50 (100%), 5 (10%), 46 (92%) and 9 (18%), respectively. Salmonella spp., Listeria monocytogenes and E. coli O157:H7 were targeted as foodborne pathogens, and the presence of those pathogens in samples were 10% (in five samples), 8% (in four samples) and 4% (in two samples), respectively. It was found that herbed cheeses containing foodborne pathogens raise an important risk for consumers’ health. Standardization and modernization of herbed cheese production, in which hygienic conditions and quality controls would be applicable, seems a necessity in order to prevent possible public health risks from herbed cheeses.