Asli Cadun

Effects of Gutting and Ungutting on Microbiological, Chemical, and Sensory Properties of Aquacultured Sea Bream (Sparus aurata) and Sea Bass (Dicentrarchus labrax) Stored in Ice

The effect of gutting and ungutting on microbiological, chemical, and sensory properties of aqua-cultured sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) stored in ice were studied. The total viable mesophilic and psychrophilic bacterial counts increased throughout the storage period of gutted and ungutted sea bream and sea bass. The mesophilic counts reached 8.19 log cfu/g for ungutted sea bream and 7.93 log cfu/g for ungutted sea bass after 14 days of storage. The mesophilic counts reached 8.89 log cfu/g for gutted sea bream and 8.16 log cfu/g for gutted sea bass after 14 days of storage. On day 14 of storage the psychrophilic counts of ungutted sea bream and sea bass were 8.24 log cfu/g and 8.03 log cfu/g, respectively, and for gutted sea bream and sea bass were 8.93 and 8.22, respectively. At the end of the storage period of 14 days, TVB-N, TBA, and TMA-N values of ungutted sea bass were determined as 50.13 ± 0.25 mg/100 g, 2.66 ± 0.06 mg malonaldehit/kg, 9.86 ± 0.01 mg/100 g respectively. TVB-N, TBA, and TMA-N values of ungutted sea bream reached 55.90 ± 0.36 mg/100g, 2.51 ± 0.21 mg malonaldehit/kg, 9.79 ± 0.01 mg/100 g on day 14 respectively. And also at the end of the storage period of 14 days, TVB-N, TBA, and TMA-N values of gutted sea bass were determined as 48.00 ± 0.26 mg/100 g, 2.48 ± 0.03 mg malonaldehit/kg, 8.71 ± 0.06 mg/100 g respectively. TVB-N, TBA, and TMA-N values of gutted sea bream reached 49.66 ± 0.77 mg/100g, 2.64 ± 0.07 mg malonaldehit/kg, 8.97 ± 0.01 mg/100 g on day 14 respectively. The result of this study indicates that the shelf-life of whole ungutted sea bass and sea bream stored in ice as determined by the overal acceptibility sensory scores, chemical quality, and microbiological results show us that the fish were spoilt on day 14. Each chemical, sensory, and microbiological result for sea bream showed us that there was a correlation and similarity and on day 14 it was spoilt.

Determination of Quality Characteristics of Holothuria tubulosa, (Gmelin, 1788) in Turkish Sea (Aegean Region) Depending on Sun Drying Process Step Used in Turkey

ABSTRACT There are around 500 species of sea cucumber but few (around 10-17) are valuable commercially. In Turkey, an Aegean region species, Holothuria tubulosa, is collected by divers and kept alive until processed. Generally, Chinese methods and processing techniques of sea cucumbers are applied in Turkey. Processing steps in Turkey consist of cleaning, gutting, boiling, cooling, sun drying, packaging and storage. In this study, quality characteristics of Holothuria tubulosa were determined depending on a sun drying process step used in Turkey: water activity (aw) and microbial quality of the sea cucumber were determined during sun drying period at different air conditions (temperature, wind velocity, humidity). Proximate analysis (crude protein, crude fat, moisture, carbohydrate) and chemical quality control analyses (total volatile base-nitrogen, trimetylamine-nitrogen, and thiobarbituric acid reactive substances) were also determined before and after sun drying of Holothuria tubulosa. According to the results of analysis, no quality criteria reached the maximum acceptability limit for the product.

Effects of Phosphate Dip Treatments on Chemical, Microbiological, Color, Textural, and Sensory Changes of Rainbow Trout (Onchorhyncus mykiss) Fillets During Refrigerated Storage

The influence of dipping rainbow trout fillets for 10 min in 5% solutions containing sodium monophosphate (MSP), sodium diphosphate (DSP), and sodium triphosphate (TSP) on microbiological, chemical, color, textural, and sensory analyses of fish fillets were assessed. Treatment of rainbow trout fillets with DSP and TSP were effective against the proliferation of total mesophilic, psychrotrophic bacteria, and coliform bacteria counts. Phosphate treatments did not affect lipid oxidation (TBA), TVB-N values, and textural qualities. According to the results of microbiological analyses, DSP and TSP extended the shelf-life of trout fillets an additional three days over the control and MSP during refrigerated storage. DSP and TSP treatments were determined more effective than MSP for inhibition of microbial growth. DSP and TSP treatments can be an alternative way to improve the shelf-life of fish and fish products.

Determination of the Tissue Distribution of PPO on Caramote Prawn (Melicertus kerathurus, Forskal, 1755) and Jinga Shrimp (Metapenaeus affinis, H. Milne Edwards, 1837) Caught from Izmir

Tissue distribution of polyphenol oxidase (PPO) was studied in caramote prawn (Melicertus kerathurus) and jinga shrimp (Metapenaeus affinis) postmortem. Activity was analyzed in different tissues: the head (cephalothorax + carapace), carapace, exoskeleton of the abdomen, pereopods, and maxillipeds, individually. Based on the results, PPO activity of jinga shrimp was determined to be higher than caramote prawn during the research period. Partial tissue distribution showed that the highest activity was determined in carapace by using 70% ammonium sulfate fractions. Partial tissue distribution was also used to determine the spread of black spots. In addition, comparison between the PPO levels of caramote prawn and jinga shrimp was performed. The importance of these species is their economic value. However, there is no available data in the literature about caramote prawn and jinga shrimp. The determined data showed us that using antioxidant chemicals would be suitable for jinga shrimp.

Control of Lipid Oxidation and Texture Changes in Frozen Sardine Mince by Combined Use of Milk Protein Concentrate and Caffeic Acid

The effectiveness of milk protein concentrate (MPC) and caffeic acid in controlling lipid oxidation and texture changes in 6-month frozen stored sardine mince was investigated using two different concentrations of caffeic acid (200 and 400 ppm) with and without MPC (4%). The extent of lipid oxidation was monitored by measuring thiobarbituric acid reactive substances (TBARS) while changes in the texture of mince due to frozen storage were assessed using Texture Analyzer (TA.XT Plus) and sensory analysis. Cooking loss upon frozen storage was also determined. The addition of MPC and/or caffeic acid significantly reduced lipid oxidation throughout the storage period. However, neither added benefit nor synergistic effect in retarding lipid oxidation was shown by caffeic acid. MPC not only retarded lipid oxidation but also moderated texture hardening, cooking loss, and moistness during frozen storage. No improvement by caffeic acid alone and no significant differences in sensory firmness and moistness between MPC-added mince with and without caffeic acid indicate that caffeic acid did not play any role in texture and moisture control. This study suggests that lipid oxidation and texture of frozen sardine mince can be better controlled by using MPC alone.

Quality of marinated shrimps : Influence of treatment, recipe and species characterised by physical measurements

The influence of processing treatments and additives on textural, water binding and colour attributes of marinated deep water pink shrimp (Parapenaeus longirostris) was determined. In addition, different shrimp types, brown shrimp (Crangon crangon) and deep water pink shrimp (PL) were compared regarding their textural, water binding and colour attributes after heat treatment to get an impression how different raw materials can influence the quality of the marinated end product. Texture measurement was performed as instrumental texture profile analysis using a texture analyser TA.XT2. Different texture parameters (hardness, chewiness, adhesiveness, cohesiveness and elasticity) were measured by double compression of the shrimps. Force of extrusion as well as Warner Bratzler shear force were also estimated. Water binding capacity was determined as expressible moisture and colour measurements were performed using a tristimulus ChromaMeter CR 300. Among the investigated variables, the marination time showed the highest influence on the textural parameters of marinated PL, whereas surprisingly almost no influence on texture parameters resulted from pre-treatment with sodium tripolyphosphate. A minor influence of all variables on the water binding capacity of marinated PL was observed, while colour values were affected moderately. Compared with refrigerated, vacuum-packed, cooked retail samples of brown shrimps (CC) differences in texture and colour were too obvious to allow a substitution of CC by PL due to completely different product characteristics.