Aerobic Mesophilic Bacteria Counts Research Articles

Analysis of microbiological contaminants in mussel Perna perna (Linnaeus, 1758), before and after depuration, from mariculture of the lowland coast, Rio de Janeiro, Brazil

Mussels can be used in the assessment of contamination of marine environments because of their filtering particles. Since they are used as a food source, this study aimed to evaluate the efficiency of the (experimental) depuration process for the microbiological quality of mussels obtained from two regions of the Baixadas Litorâneas in Rio de Janeiro. Samples of cultivation water and mussels were collected seasonally from March 2019 to February 2020, in a total of 240 animals from both regions to perform the Most Probable Number of coliforms at 35 °C, at 45 °C (E. coli), Enterococcus spp., research Salmonella spp., count of heterotrophic aerobic mesophilic and psychrotrophic bacteria in control samples and debugged. A low count of E. coli was observed for the cultivation water, but in mussels the counts were high in the winter period in Armação de Búzios, exceeding the limits established in accordance with the current legislation. However, the depuration technique adopted after collection provided a reduction in bacteriological counts, proving to be an effective process. Therefore, if there is a bacterial reduction with the adoption of the depuration process, there is a need for mitigation measures adopted by mariculturers and city halls regarding the safety of marine waters and molluscs.

Biochemical content of cherry laurel (Prunus laurocerasus L.) fruits with edible coatings based on caseinat, Semperfresh and lecithin

Cherry laurel is one of the most important cherry species and naturally grown in Black sea region in Turkey. Its fruits are sold at high price in local markets in northern parts of Turkey. Cherry laurel fruits are very perishable with a limited shelf life due to a high metabolic activity and susceptibility to mechanical damage and microbial attack. The effect of edible coatings (EC) based on caseinat, Semperfresh and lecithin on the fruit quality, bioactive content and antioxidant activity of cherry laurel fruits stored at 4 ± 1 °C for 15 days was evaluated. The EC fruits compared with uncoated fruits in terms of weight loss, brix, color, pH, titratable acidity, reducing sugar, total sugar, sucrose, total phenolic content, DPPH-IC50, ABTS-IC50, total yeast-mold count, number of total mesophilic aerobic bacteria and ascorbic acid (Vitamin C). Results showed that Semperfresh coating was more promising on titratable acidity (0.26%), pH (4.63), invert sugar (11.77 g/100 g), total sugar (11.96 g/100 g) and sucrose (0.13 g/100 g), caseinat coating was found more promising for count of total yeast-mold count (2.93 log kob/g) and total mesophilic aerobic bacteria (3.44 log kob/g) and lecithin coating was more promising in terms of weight loss (6.77%). For radical scavenging activity and total phenolic content, Semperfresh was found more useful. Thus, caseinat, Semperfresh and lecithin showed to be a promising alternative in prolonging shelf life and preserving the quality of cherry laurel.

Pathogenic bacteria load and safety of retail marine fish.

This study was conducted to determine the pathogenic bacteria load of 14 species of marine fish obtained from two suppliers (in Bitlis city, Turkey), which provide fish for fish markets, and to reveal the safety of the marine fish in terms of microbiological quality. The counts of total mesophilic aerobic bacteria (TMAB), Staphylococcus aureus, and Escherichia coli, the presence of Salmonella spp. and Listeria monocytogenes were determined in anchovy, horse mackerel, salmon, red mullet, gilthead seabream, bonito, pilchard, common sole, sand smelt, axillary seabream, seabass, Mediterranean horse mackerel, bluefish, and garpike. It was determined that common sole, axillary seabream, seabass, bluefish and Mediterranean horse mackerel obtained from both suppliers were unacceptable in terms of the counts of TMAB. Twenty-four samples exceeded the critical limit of S. aureus and all the samples were unacceptable according to the critical limit of E. coli. While L. monocytogenes was isolated from 50.0% of the samples, Salmonella spp. was isolated from 39.3% of the samples. These results showed that the pathogenic bacteria load of the analyzed marine fish was quite high and they were unsafe in terms of microbiological quality.

Dietary supplementation of Agaricus bisporus stalk meal on growth performance, carcass and organ traits, meat quality, cecum mesophilic aerobic bacteria counts and intestinal histology in broiler chickens

ABSTRACT: Effects of dietary Agaricus bisporus mixture or stalk or cap on growth performance, carcass components and some meat quality parameters, mesophilic aerobic bacterial counts, and intestinal histomorphology in broiler chickens were investigated. Two hundred and forty one-day-old male Ross 308 broiler chickens were divided into 4 experimental groups with 4 replicates, each including 15 birds. Chickens were fed with basal diet (C), mushroom mixture (MM, 10 g stalk+10 g cap/kg diet), mushroom stalk (MS, 20 g/kg diet) and mushroom cap (MC, 20 g/kg diet). Feed conversion ratio (FCR) was improved (P < 0.01) by dietary MS while feed intake (FI) decreased (P < 0.01) in all treatment groups compared to control. However, body weight gain (BWG) was decreased (P < 0.01) by MC inclusion. Mushroom supplemented groups had higher (P < 0.05) mesophilic aerobic bacteria in the cecum. MS inclusion increased villus height to crypt depth ratio in the jejunum (P < 0.01) and villus height in the ileum (P < 0.01) and jejunum (P < 0.05). MC increased (P < 0.01) crypt depth in the jejunum. There were no statistical differences among groups for carcass components (P > 0.05). The L* values were decreased (P < 0.01) in thigh meat but increased (P < 0.01) in breast meat by mushroom inclusion. The a* values were decreased (P < 0.01) and b* values were increased (P < 0.05) in both thigh and breast meat with mushroom addition to diet. The obtained results indicated that A. bisporus stalk meal at an inclusion level of 20 g/kg of diet had favourable effects on growth performance with higher feed efficiency, improved intestinal morphology with higher villus height and increased meat quality of broiler chickens.

Mikrodalga Destekli Buharlı Kurutma ve Dondurarak Kurutma Tekniklerinin Ham Buğday Ruşeyminin Antioksidan Aktivitesi ve Mikrobiyolojik Kalitesi Üzerine Etkileri

The purpose of this research was to study the effects of stabilization and storage conditions on the antioxidant activity and microbiological quality of raw wheat germ (R). For this reason, the raw germ samples were stabilized by microwave-assisted steam drying (MWS) and freeze-drying (FD) methods, and they were stored at different storage temperatures (-18, + 4 and 25°C) with polyethylene bags for 90 days. The total phenolics contents (TPC), antioxidant activities (DPPH and TEAC assay methods), and the counts of total mesophilic aerobic bacteria (TMAB), and the total yeast-mold count (YMC) of the germ samples were investigated. Methanol extracts of FD samples showed higher TPC and antioxidant activity than MWS samples significantly (p

Black garlic as a substitute for fresh garlic to reduce off‐flavor and enhance consumer acceptance and bioactive properties in cemen paste

The effects of black garlic aged at different periods as a substitute for fresh garlic (FG) on the overall quality of pastırma cemen paste were evaluated during 90 days of storage. The addition of black garlic increased the phenolic content and antioxidant activities of the cemen pastes, and decreased the firmness, stickiness, pH and color values compared to CON (Control). Total aerobic mesophilic bacteria counts of cemen pastes containing black garlic aged for ≥21 days were similar to those of CON, but the counts of yeast and molds of black garlic added-groups were higher than CON during storage. Incorporation of black garlic to cemen paste increased the content of volatile compounds such as esters and terpenes with fruity and sweet notes, while the concentration of sulfur compounds decreased. In this way, the off-flavor of cemen paste was eliminated and its sensory acceptability improved. Considering the overall data, the best results were obtained in the CP3 group produced with black garlic aged for 21 days. Consequently, black garlic can be used as a substitute for FG to improve the consumer acceptance and bioactive properties of cemen paste. Novelty impact statement Some consumers avoid pastırma consumption because of the unpleasant off-flavor from cemen paste. Overcoming this problem is very important for both the producer and the consumer. The results of this study showed that black garlic improved the sensory acceptability and bioactive properties of cemen paste by eliminating the unpleasant smell of fresh garlic and increasing the antioxidant capacity. In conclusion, the use of cemen paste with black garlic in pastırma production has promising potential to enhance consumer acceptance and retard oxidative reactions.

Optimization of ozone concentration and storage time in green asparagus (Asparagus officinalis L.) using response surface methodology

Background: Asparagus (Asparagus officinalis L.) green is a vegetable with a great demand worldwide, and likewise, it is highly perishable due to its high respiration rate that accelerates its senescence. Disinfection of vegetables after their harvest is an obligatory practice that can reduce losses by decomposition due to the attack of microorganisms. Therefore, it is vital to preserving its microbiological and sensory characteristics to reach the final consumer. Objective: To evaluate the effect of gaseous ozone (0 to 10 ppm) and storage time (0 to 30 days) on phenol content, overall appearance, count of molds, psychrophilic bacteria, and viable mesophilic aerobes. Methods: the response surface methodology was used, applying a rotatable central composite design. Results: The results indicated that there was a significant influence (p <0.05) of the independent variables on the characteristics studied, as well as an adequate lack of fit of the quadratic regression model (p> 0.05). By means of the contour superposition technique, it was determined that the optimal conditions for the highest retention of phenol content (16.99 mg/g) and overall appearance (7.61 points) and lower counts of viable aerobic mesophilic bacteria (5.3 x 103 CFU/g) they corresponded to 10 ppm of gaseous ozone up to 25.91 days of storage, with adequate quality characteristics in the shoots. Conclusion: the region of interest was determined for optimal retention of phenol content and overall appearance, and a lower count of viable aerobic mesophilic bacteria in green asparagus during postharvest, suggesting to use the initial application of ozone gas at 10 ppm allowing 25.9 days storage at 1 °C. The results indicate that this technology is a good alternative in the conservation of fresh vegetables.

Microbial quality and labeling of minimally processed fruits and vegetables

The consumption of minimally processed, or ready-to-eat (RTE), fruits and vegetables has been growing because people have shorter time to eat and due to the pursuit of convenience and health benefits. Minimal processing includes raw material selection and sorting, pre-washing, debarking, cutting, slicing, sanitizing, rinsing, centrifuging, and packing. Thus, natural protection barriers are affected during cutting methods and they release nutrients that enable microorganism growth. The aim of the current study was to evaluate the levels of aerobic mesophilic bacteria, molds and yeasts, coliforms at 35°C, Escherichia coli and Salmonella sp., as well as the labeling adequacy of minimally processed fruits and vegetables traded in Vitória, Espírito Santo, Brazil. Fruits and vegetables presented aerobic mesophilic bacteria, molds and yeasts, and coliforms at 35°C, above the safe limit for consumption purposes. The count of aerobic mesophilic bacteria in RTE fruits ranged from 4.00 to 6.30 Log CFU/g. The highest count of this microorganism group was recorded for fruit salads. Salmonella sp. was not identified in fruit or vegetable samples, whereas Escherichia coli was detected in four vegetable samples. None of the evaluated labels (n = 40) followed the Brazilian legislation. Minimally processed fruits and vegetables had poor microbiological quality and labeling was also unsatisfactory. The adoption of good manufacturing practices and quality control tools as strategies to produce safe food can help minimizing risks to consumers’ health.

Natural preservative‐based shelf‐life enhancement of borde: A traditional Ethiopian low alcoholic beverage

Borde is a cereal-based low alcoholic fermented beverage with a short shelf-life (fast spoilage due to over-acidification). Thus, the research aims to enhance the shelf-life. The counts of aerobic mesophilic bacteria and yeast in samples with 0.1 g/100 ml sodium benzoate and control sample (without preservatives) decreased considerably during the 14 days of storage. There were no significant differences (p > .05) in counts of lactic acid bacteria for 14 days in borde samples treated with all preservatives. Likewise, the counts of yeast showed no significant differences for 12 and 10 days between borde samples treated with 10 g/100 ml Moringa oleifera (6.48 ± 0.04 to 6.42 ± 0.01), and 10 g/100 ml Thymus schimperi (6.49 ± 0.03 to 6.00 ± 0.07), respectively. Borde samples treated with 10 g/100 ml T. schimperi were more acceptable than those treated with 10 g/100 ml M. oleifera. Hence, T. schimperi was the candidate preservative for the preservation of borde. Practical applications The practical application of the use of these natural preservatives is the feasibility and ease of the method for preservation of low alcoholic cereal-based beverages (borde) even at household level among those who cannot afford alternative preservatives. Besides, natural preservatives (Moringa oleifera and Thymus schimperi) are naturally safe, accessible, and nutritious in addition to their role in enhancing the shelf life of beverages. Thus, the current findings could pave way for further evaluation of these plants and others for their application in many other fermented products, be it alcoholic or non-alcoholic beverages.

A Fibre- vs. cereal grain-based diet: Which is better for horse welfare? Effects on intestinal permeability, muscle characteristics and oxidative status in horses reared for meat production.

Horses reared for meat production are fed high amounts of cereal grains in comparison with horses raised for other purposes. Such feeding practice may lead to risk of poor welfare consequences. The aim of this study was to investigate the effects of two feeding practices on selected metabolic parameters and production aspects. Nineteen Bardigiano horses, 14.3 ± 0.7 months of age, were randomly assigned to two groups—one fed with high amounts of cereal grains (HCG; n = 9; 43% hay plus 57% cereal grain‐based pelleted feed) vs. one fed with high amounts of fibre (HFG; n = 10; 70% hay plus 30% pelleted fibrous feed)—for 129 days. At slaught on abattoir, biological and tissue samples were collected to evaluate the microbiological contamination of mesenteric lymph nodes and liver; selected meat quality traits (chemical composition and fatty acid profile of the Longissimus thoracis et lumborum muscle); and the oxidative status of the horse. A linear mixed model was used: dietary treatment and sex were fixed effects and their interaction analysed on production and metabolic parameters as dependent variables. Results showed an increased intestinal permeability in the horses fed HCG compared to HFG, according to the significant increased total mesophilic aerobic bacteria counts in mesenteric lymph nodes (p = 0.04) and liver samples (p = 0.05). Horses in HCG showed increased muscle pH (p = 0.02), lighter muscle colour (L) (p = 0.01), increased intramuscular fat concentrations (p = 0.03), increased muscle glutathione peroxidase and superoxide dismutase activities (p = 0.01 and p = 0.03, respectively). Moreover, horses in HCG had lower muscle water holding capacity at interaction with sex (p = 0.03, lower in female), lower muscle protein content (p = 0.01), lower concentration of muscle PUFAs (p = 0.05) and lower plasma catalase activities (p = 0.05). Our results showed that feeding a high cereal grains diet can have global effects on horse physiology, and thus represents a threat for their welfare.

Kalamar örneklerinde tekstürel bozulmanın tespiti: Üç farklı aracın mikrobiyolojik, görsel ve fiziko-kimyasal analizlerle desteklenmesi

The aim of the present study was to reveal the textural profile changes like hardness, cohesiveness, springiness, and adhesion supported by total mesophilic aerobic bacteria count (TMABc), pH, and some visual sensory characteristics in squid samples stored at 4 ºC. Three different Brookfield Texture Analyzer tools, named TA7, TA9, and TA18 were used to observe the textural changes more clearly. The difference of TMABc between the storage days reached from 4.32 log CFU/g to 6.32 log CFU/g. The hardness value of the squid samples, detected by TA18 and TA9 tools, increased while the hardness value obtained from TA7 was higher. The highest change in cohesiveness value in the squid samples was defined by the TA9 tool as ~63%. Once springiness values detected by TA9 were sharply decreased from 4.9 mm to 2.1 mm, those of TA7 and TA18 were slowly decreased. The most increase in adhesion value (0.08 mJ to 0.21 mJ) was obtained in the TA7 tool. Depending on the textural quality changes, the pH value was increased, and as visual and sensory, dark, or yellow spots were observed. The present study results revealed that especially the TA18 tool could be effectively used to determine the quality changes of the squid samples.

Determination of the Risky Microorganisms in Frozen Ready-to-Eat Seafood Sold in Istanbul Market

Since frozen ready-to-eat seafood has the potential to cause food poisoning, this study focuses on microorganisms that have the potential to be a health hazard found in frozen ready-to-eat seafood, which is sold to highly populous communities. Therefore, the most popular frozen ready-to-eat seafood, fish balls and surimi crab legs, from Istanbul market were studied. Samples were gathered from seven different branches of four major chain market brands, twice in winter (October-March) and twice in summer (April-September). As a result of seasonal conditions summer samples had higher microbial loads compared to winter samples. The average mesophilic and psychrophilic aerobic bacteria counts of fish balls and surimi crab legs were below ≤4 log cfu/g. All samples were safe in terms of Salmonella, Vibrio parahaemolyticus and Vibrio cholerae; and acceptable in terms of Staphylococcus aureus Clostridium perfringens, and Bacillus cereus. The microbiological load of fish balls was higher (p<0.05) than the other samples. It was observed that more than 80% of them are risky in terms of coliform bacteria. It is concluded that attention should be paid especially to minced and spice added products. It is essential to pay more attention to the marketing of ready-to-eat seafood during the summer seasons for the prevention of public health.

EFFECTS OF HIBISCUS (Hibiscus sabdariffa L.) AND POPPY (Papaver rhoeas L.) EXTRACTS ON DOUGH AND BREAD PROPERTIES THE USAGE OF HIBISCUS AND POPPY IN BREAD

In this study, it was aimed to examine and compare the effects of Hibiscus (Hibiscus sabdariffa L.) and poppy (Papaver rhoeas L.) extracts on some chemical, physical, microbiological and sensory properties of bread dough and bread. The pH, L, b, chroma, hue values of the dough decreased by usage of hibiscus extract, while the a value was increasing. It was determined as the lowest pH was 4.13; L 39.23; b 5.08; chroma was 6.55, hue angle was 54.65 and the highest a value was 7.20. Counts of total mesophilic aerobic bacteria and yeast/mold were found lower in dough with hibiscus extract. Hibiscus extract application gave the lowest specific volume value (2.15 mL/g). In terms of hardness, gumminess and chewiness, the highest values were obtained in hibiscus bread as 24.96 N, 16.13 N and 147.86 mj, respectively. Sensory properties scored of the breads were lower than the control bread.

An evaluation of the chemical content and microbiological contamination of Anatolian bee venom.

Bee venom is a natural substance produced by worker bees. The aim of this research paper is to determine the characteristics of Anatolian bee venom by evaluating its chemical content and microbiological properties. Physical, chemical and microbiological analyses were performed on 25 bee venom samples from different areas of Anatolia, Turkey. Data obtained by 3-replicate studies were evaluated with normality and one-way and two-way ANOVA / Tukey tests. Chemical analyses of the bee venoms revealed average melittin, apamin, and phospholipase A2 contents of 40.57%, 2.12% and 13.67%, respectively. The results suggest that Anatolian bee venom has a high phospholipase A2 content compared to the previous literature. The results for apamin content were similar to those reported in other countries. Melittin content was within the range of standard values. Bee venom samples were also observed to have a high sugar content, associated with pollen and nectar contamination. Total aerobic mesophilic bacteria counts revealed no microbial development in 11 samples of bee venom. Staphylococcus aureus was not detected in any sample. A low microbial load was associated with a high phospholipase A2 content in the bee venom composition, thus contributing to its antimicrobial character. This study presents an examination of Anatolian bee venom in terms of chemical content and microbial quality. The examination of other components in addition to phospholipase A2, melittin and apamin in future studies, together with an analysis of antimicrobial properties will further our understanding of Anatolian bee venom.

Assessment of technological characteristics and microbiological quality of marinated turkey meat with the use of dairy products and lemon juice.

ObjectiveThe aim of this study was to evaluate the effect of marinating turkey meat with buttermilk and acid whey on the technological traits and microbiological quality of the product.MethodsSlices of turkey meat muscles were marinated for 12 hours in buttermilk (n = 30), acid whey (n = 30) and comparatively, in lemon juice (n = 30). The control group (n = 30) consisted of unmarinated slices of turkey breast muscles. Physical parameters (pH, water holding capacity, colour L*a*b*, shear force, weight loss) were assessed and quantitative and qualitative microbiological evaluation of raw and roasted products was performed. The microbiological parameters were determined as the total viable counts of mesophilic aerobic bacteria, of the Enterobacteriaceae family, and Pseudomonas spp. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.ResultsMarinating turkey meat in buttermilk and whey compared to marinating in lemon juice and the control sample resulted in a higher (p<0.05) degree of yellow color saturation (b*) and a reduction (p<0.05) in the number of mesophilic aerobic bacteria, Pseudomonas spp. and Enterobacteriaceae family as well as the number of identified mesophilic aerobic bacteria in both raw and roasted samples. The lowest (p<0.05) shear force values were found in products marinated in whey.ConclusionThe use of buttermilk and acid whey as a marinade for meat increases the microbiological safety of the product compared to marinating in lemon juice, while maintaining good technological features of the product.

Application of PET/Sepiolite Nanocomposite Trays to Improve Food Quality

New PET and nanosepiolite materials are produced for its application in innovative packaging with better performance. In our previous work, we demonstrate that the use of different percentages of sepiolite modified with different organosilanes improved mechanical and barrier properties of PET. Nanocomposites permeability can decrease up to 30% compared to that of pure PET and the mechanical analyses show that, although PET nanocomposites are more brittle than virgin PET, they are also harder. In the present work, we are going to study the properties of this innovative packaging with real food analyzing mechanical properties related to the product transport together with permeability and microbiological characteristics. At the same time, it has been seen that it is possible to lighten trays, which is very important both industrially and environmentally. On the other hand, a good quality packaging for food needs to ensure that organoleptic and physico-chemical characteristics of the product inside are not modified due to migration of any of the packaging material to the food itself. Results obtained in this work also show lower count of aerobic mesophilic bacteria and Enterobacteriaceae (EB), reducing the incidence of food contaminations by microorganisms.

Effect of gaseous ozone application during chilling on microbial and quality attributes of pig carcasses.

Ozone application has been suggested as an additional measure to the slaughter animals under hygiene programs. In this study, we determined the efficacy of gaseous ozone applied to pig carcasses during chilling (16 h at 2-5°C). Forty carcasses were allocated to each treatment: control, without ozone application (T1) and 5 ppm gaseous ozone application (T2), divided in two 4-h periods. The carcasses were sampled before and after chilling. The average counts of total aerobic mesophilic (TAM) bacteria before chilling were not different (p = 0.55) between T1 and T2. In turn, after chilling, the ozone-treated carcasses had significantly reduced about 0.4 colony-forming units (CFU)/cm2 of TAM counts (p < 0.001) than the control carcasses. No significant reduction was observed in the number of carcasses positive for Listeria sp. and Escherichia coli after gaseous ozone treatment; while a tendency (p = 0.08) of lower number of Salmonella positive carcasses in T2 was observed. Common macrorestriction (pulsed-field gel electrophoresis) patterns of S. enterica were observed in the carcasses before and after chilling. Pork samples from treated and untreated carcasses with ozone showed no lipid oxidation or altered color and pH. The results indicate that the gaseous ozone in the tested protocol is effective in reducing TAM populations, but not effective in decreasing the number of carcasses positive for E. coli and Listeria sp. Regarding Salmonella, the tendency of positive carcasses reduction may encourage further studies by testing other protocols of gaseous ozone application inside the chilling chamber.

Effect of Different Plant Extracts Added to Ice on Sensory Preference of Sliced Salmon

almon is usually sold in slices on ice in retail markets. Since ice is in direct contact with fish, it affects the sensory characteristics as well as the physicochemical properties. Improving the properties of ice can make positive contributions to fish flavor and consumer preference. In this study, sliced salmons were treated with ice containing one of either basil (B), rosemary (R), laurel (L), oregano (O) or fennel (F) extracts. Iced salmon without any plant extract was the control (C) group. Displaying sliced fish for sale on ice and placing back to cold room at the end of the day is a common practice. Samples were covered with ice, stored at 18±1°C during daytime and taken to the cold room (2±1°C) at night to simulate marketing conditions. Adding plant extracts to ice resulted in a remarkable change in fish flavor, and R, F, and L were the most popular treatments among all groups. In particular, rosemary-added ice significantly (P&lt;0.05) increased the preference of consumption. Panelists emphasized that F samples can be consumed as appetizers. Dominant and pleasant aroma was also stated for L samples. The mesophilic aerobic bacteria count remained below 5 log CFU/g in all samples during 4 days. The total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS) and pH values of all groups remained within the limits of acceptability. Using plant extract-added-ice provided a suitable quality sale of salmon for 4 days and offered an option to consumers by giving the product different flavors.&nbsp;

Protective effect of grape seed oil-loaded nanofibers: Limitation of microbial growth and lipid oxidation in kashar cheese and fish meat samples

Grape seed oil-loaded nanofibers (gsN) having 414.8 ± 58.7 nm diameter were fabricated using the electrospinning technique. Scanning electron microscopy images, encapsulation efficiency (92.4%), and molecular characterization analysis (FTIR) proved successful production of electrospun gsN. Limitation in total mesophilic aerobic bacteria count (TMABc) of kashar and fish meat samples coated with grape seed oil-loaded nanofibers and then stored at cold storage conditions was found in the range of 1.40 and 1.53 log during the experimental period. Coating with gsN as compared to the control group samples for each sample delayed rapid total yeast and mold growth in kashar (28%) and fish meat samples (20%) (p < 0.05). TBA value of fish control samples was increased from 1.38 to 2.06 mg MDA/kg in fish control samples and 1.65 mg MDA/kg in fish meat coated with gsN. In addition to fish samples, at the end of the 20th day, while the initial TBA value was determined as 1.32 mg MDA/kg, it reached 2.45 in kashar control samples and 2.18 mg MDA/kg in kashar coated with gsN. In this respect, besides microbiological limitation, grape seed oil nanofiber coating was found to be highly effective against the rapid oxidation in fish and kashar samples stored at 4 ± 1 °C (p < 0.05). The use of grape seed oil within nanoformulation effectively provided obtaining higher quality products having two different matrices in the food industry. Therefore, this nano methodology provided with the electrospinning technique could play a guiding role for different food products in the industry as well.

Combination effect of hot smoking and vacuum packaging on quality parameters of refrigerated thornback ray (Raja clavata Linnaeus, 1758)

In this study, hot smoking process was applied to thornback ray (Raja clavata), which is a non-target catch, and the product obtained was vacuum packaged and then stored at refrigerated conditions (4±1 °C) for 120 days. The nutritional, chemical, microbiological, and sensory changes in the products were examined every 15 days. After the hot smoking process applied to thornback rays, significant changes were observed in the nutritional composition of the products (P&amp;lt;0.05). Total volatile basic nitrogen (TVB-N), trimethylamine nitrogen (TMA-N), and thiobarbituric acid (TBA) values of smoked thornback rays increased during storage, and these values were determined between 23.11-98.06 mg/100 g, 2.48-7.33 mg/100 g, and 0.1-0.3 mg malondialdehyde/kg, respectively. It was determined that the total aerobic mesophilic bacteria (TAMB) count detected in the fresh sample decreased in smoked products due to the smoking process and the value was found below the detectable limit value (1.47 log CFU/g) during storage. As a result of the sensory evaluation, it was determined that the texture, odor, and flavor criteria of the smoked thornback rays were below the consumable limit value on the 120th day. According to the results, it was determined that the thornback ray vacuum packaged by hot smoking can be consumed safely for 105 days at 4±1 °C. This study shows that discarded thornback rays, which are a high protein food, can be transformed into high value-added products by applying different processing methods such as smoking and so can be evaluated as human food.