Food Engineer

Color of sun-dried tomato is an important quality criteria and color stability of sun dried tomatoes is affected by storage conditions such as temperature, time and packaging type. The objective of this study was to investigate the effects storage time, storage temperature and packaging type on color stability of sun-dried tomatoes by using factorial experimental design. In this study, the 2 3 factorial design was used to represent mathematical relationship between the storage conditions and color values (L and a/b) and used to verify whether or not factor variables of storage conditions are effective on color. Results in experimental model showed that all factors had negative effects on the color values which indicated the reducing stability of color. The main effect was found to be the time having the highest coefficient (-3.3 for L and-0.12 for a/b) in design models and storage temperature was found to be the least effective factor. Design model and response surface plots revealed that storage temperature could be kept around 20°C for 9 months and storing under vacuum packaging should be selected to reduce color losses for the safe storage conditions.

This study aimed to optimize the extraction conditions for Sorbus umbellata (Desf.) Fritsch var. umbellata leaves to maximize the phenolic content and their antioxidant activity and to investigate β-glucuronidase (GUS) enzyme inhibitory, antimicrobial and cytotoxic potentials of the extracts obtained under optimum conditions. The optimum extraction conditions were found to be 78.2 and 79.7% solvent, 73.1 and 71.5°C, and 89.9 and 88.8 min to maximize phenolic content and antioxidant activity, respectively. Low values of coefficient of variations indicate the high reliability and reproducibility of the conducted extraction experiments. Bioactivity results showed that extracts had cytotoxic effect on the MCF-7 and A549 cells where the highest cell proliferation inhibition was observed for the A549 cell line (71.8% at 150 μg/mL). Staphylococcus aureus showed highest zone of inhibition (19.3 mm) in all bacteria followed by Escherichia coli. Additionally, extracts displayed potential GUS inhibitory activity. In conclusion, Sorbus umbellata leaf extract can be obtained by optimized cost-saving extraction and has a potential bioactivity to be utilized as a food ingredient for high value-added products and/or nutraceuticals development where it can combat oxidative stress and GUS mediated reactive metabolite formation.

The aim of this study is to obtain the grape seed extract with high antioxidant activity and to investigate the quality characteristics of traditional yogurts fortified with seed extracts at different concentrations. For this aim, batch hot water extraction was conducted and extraction conditions were optimized to produce Vitis vinifera L. grape seed extract using with the highest antioxidant activity. The fortification of yogurts was conducted at 0.1-0.15 and 0.2 g/ 100g extract level and antioxidant, physicochemical, microbial and sensory characteristics of the yogurt samples were analyzed. Results showed that antioxidant activity of fortified yogurts were higher and up to 14 % more antioxidant activity was detected compared to the control samples. Yogurt samples preserved their physicochemical characteristics. Although sample with 0.1 g/100 g extract had highest scores in overall acceptance, the sample containing the highest extract concentration of 0.2 g/100 g, exhibited negative perceptions by panelists in sensorial analysis. In conclusion, grape seed may be used in traditional yogurt production by improving the taste and antioxidant potential. The fortification levels of 0.1-0.15 g/100 g grape seed extract might be more feasible in functional yogurt production and might be more recommended for consumer's appreciation in terms of positive health effects.

Turkish delight is a sugar-based jellylike confection that has been produced for hundreds of years. In this study, four different modified atmospheres were created in order to extend the shelf life of Turkish delight. Microbiological analyses and sensory evaluations were conducted at the beginning of storage and at 7-day intervals thereafter. Microbiological analyses showed that the numbers of total mesophilic aerobic bacteria within samples stored in a modified atmosphere of 30% CO2 plus 70% N2 were lower than in the other modified atmospheres. According to sensory evaluations, the samples kept in a modified atmosphere of 50% CO2 plus 50% N2 were unacceptable after the 21st day of storage, whereas those kept in modified atmospheres of both 25% CO2 plus 75% N2 and 30% CO2 plus 70% N2 were found to be acceptable even after 30 days of storage.

The effects of different cooking methods (boiling, frying, oven-roasting and grilling) on certain properties of beef longissimus dorsi were studied. Cooking loss, moisture content, color, TBARS and the composition of fatty acids were determined. The highest cooking loss was observed with regards to boiling (P < 0.05). TBARS increased with boiling and oven- roasting (P < 0.05), whereas frying and grilling had no significant effect on TBARS (P > 0.05). Color indices were significantly changed through cooking (P < 0.05). Polyunsaturated fatty acid (PUFA) content increased in all cooking methods, while saturated fatty acids (SFA) content decreased in all treatments. The trans fatty acid (TFA) content increased after frying and oven-roasting, whereas boiling and grilling decreased the trans fatty acid content (P < 0.05). Grilling provided minimum cooking loss (P < 0.05) as well as the lowest TBARS value (P < 0.05), probably due to the structure of fire brick barbeque...

In this research, the suitability of tench (Tinca tinca L., 1758) for the production of fish cake and changes in nutrient components were determined. The supplied fish materials were minced followed by forming into fish cakes with the addition of various additives. Chemical and organoleptic analyzes of the minced fish and fish cakes were made. Also, thiobarbutyric acid (TBA), total volatile basic nitrogen (TVB-N), pH parameters were determined and total mesophilic aerobic bacteria (TMA), total psychophilic bacteria (TPA), coliform group bacteria, and yeast-mold counts were performed in fish cakes on the 1., 4., 7. and 10. days of the storage at 4 ± 1 °C. According to the organoleptic analysis findings, the fish cakes obtained from tench were considered suitable for consumption. TBA, TVB-N, pH values, and microbiological analysis results of storage have shown that deterioration occurs as storage time increases. Especially the changes after the 7th day of storage are statistically sig...

Bu arastirmada, Firat Nehri uzerinde yer alan Ataturk Baraj Golu’nde yasayan Luciobarbus mystaceus (Pallas, 1814)’un esey dagilimi, yas kompozisyonu, buyume, yas-boy, yas-agirlik ve boy-agirlik iliskileri, kondisyon faktoru, ureme yasi, ureme zamani ve yumurta sayisi gibi ozellikleri incelenmistir. II – VIII yas arasinda dagilim gosteren toplam 397 bireyin % 38,29 ’u disi ve % 61,71 ’i erkek olarak belirlenmistir. Catal boy degerleri 22 cm ve 97 cm, agirliklari ise 160 g ile 13272 g arasinda degismektedir. Kondisyon faktoru degerleri disilerde 0,628-1,623 ve erkeklerde 0,524-1,661 arasinda degismektedir. Eseysel olgunluk yasi her iki esey icin III yas olarak belirlenmistir.

Bu çalışmada, jeotermal enerjiyle kurutulmuş alıç (% 0-15) ilave edilerek dondurma üretilmiştir. Dondurmalarda fiziksel, kimyasal ve duyusal analizler takip edilmiştir. En yüksek a*, b* değeri ve en düşük L* değeri % 15 alıç ilaveli dondurmalarda ölçülmüştür. Alıç ilaveli örneklerde ilk erime ve tamamen erime sürelerinde artış, hacim oranında azalış belirlenmiştir. Alıç ilavesi dondurmaların sertlik değerleri arttırmıştır. Dondurmalarda Na, Mg, K, Fe, B ve S miktarlarında alıç ilavesiyle artış tespit edilmiştir. Alıç kullanımı duyusal açıdan dondurmalarda erimeye direnç puanını arttırmıştır.

The effects of rosemary powder, rosemary extract and a-tocopherol, and their combinations , on color, chemical and microbiological quality of Turkish sucuk during ripening and storage periods were investigated. The combination of 500 ppm rosemary extract and 500 ppm tocopherol had the highest antioxidant activity while the control group had the lowest antioxidant activity. The 500 ppm rosemary extract and 500 ppm tocopherol addition preserved color better than any other treatment. The multiplicative product of strong ripening time, antioxidant treatment interaction storage time and antioxidant treatment interaction (P < 0.0001) existed for 2-thiobarbituric acid-reactive substances content. Microbiological properties were improved by antioxidant treatment with the best microbiological quality observed for sucuks having the 500 ppm rosemary extract and 500 ppm tocopherol. To preserve overall color, chemical and microbiological quality of sucuks during storage time, the rosemary extract and tocopherol combination can be used for the commercial processing of Turkish sucuks. PRACTICAL APPLICATIONS Turkish sucuk is a popular and relatively high-fat-content (up to 40%) processed meat product. Since fat in the Turkish sucuk's formula is prone to lipid oxidation, using natural antioxidants such as rosemary extract and tocopherol may have important implications for sucuk processors. Moreover, Turkish sucuk is a raw-fermented processed meat product and natural antioxidants may also extend its microbiological life by minimizing food safety problems associated with uncooked processed meat products. To sum up, our study proving the efficacy of using natural antioxidant in Turkish sucuk processing may increase market share of Turkish sucuks.

Poppy seed paste was used in koefte production as an animal fat replacer and efficacy of using poppy seed was investigated. The use of ground poppy seed in formulation of meat burgers had no effect on the moisture content of uncooked meat burgers; however, it did have a significant effect (p b 0.05) on the fat content of meat burgers. Ground poppy seed addition significantly affected (p b 0.05) cooking yield, moisture retention, and fat retention of meat burgers. Ground poppy seed addition significantly decreased (p b 0.05) saturated fatty acid contents as the amount of ground poppy seed increased in meat burgers. A strong significant decrease (p b 0.05) on the cholesterol content of meat burgers with ground poppy seed addition was observed. Samples having 20% ground poppy seed had significantly better texture and juiciness score (p b 0.05) than any other sample which could be explained by increased moisture retention. Replacing animal fat with ground poppy seed paste is effective and may pave the way for an innovative meat product.

In this study, it was aimed to determine organochlorine pesticides (OCPs) in three types of milk (cow's, buffalo's, and sheep's milk) produced in Afyonkarahisar province of Turkey. The results indicated that these milk specimens were found to be contaminated by 21 different pesticides. Sixteen OCP residues were detected in sheep's milk and it was followed with 14 pesticides in buffalo's milk and 11 pesticides in cow's milk. Dominant pesticides in all samples examined were beta-HCH in buffalo's, cow's, and sheep's milk in the concentrations of 63.36, 91.32, and 122.98 ng/ml, respectively. Total OCP levels were found to be 243.

Cornus mas L. is a naturally growing dogwood species in Anatolia. In present study, the antioxidant activity of 50% aqueous methanol extracts of 12 cornelian cherry types were evaluated by various antioxidant assay, including free radical scavenging, hydrogen peroxide (H 2 O 2) scavenging and metal (Fe +2) chelating activities. The methanolic fruit etxracts of the Cornus mas L. fruit types (H 2 O 2 and diphenylpicrylhydrazyl (DPPH) scavenging activities, Fe +2 chelating activity) examined in the assay showed the strongest activities. The highest antiradical activity was found 44-05 type (0.943) followed by 44-04 (0.860), 77-09 (0.810) and 77-05 (0.723) types respectively. The lowest value was found 44-01 (0.537), 77-06 (0.580), 77-11 (0.567) and 77-02 (0.563) types. The highest chelating activity was found; 44-05 (54.213%), 44-04 (49.890%), 77-09 (47.287%) and 77-05 (45.180%) cornelian cherry type respectively. The lowest cheting activity was found 77-06 (33.883%), 44-01 (34.106%) and 77-11 (34.510%) types. In terms of H 2 O 2 inhibition, the highest rate was obtained from 44-05 (79.103%), the lowest one was 44-01 type to be 37.720%.

The objective of this study was to extend the shelf life of ground beef in
chilled conditions. Samples were treated with 2% salt, 2% salt + 500-ppm
ascorbic acid, or 2% salt + 100-ppm sodium nitrite. The control sample did
not contain any additives. Protein, nitrite, moisture contents, pH, thiobarbituric
acid (TBA) value, color attributes and microbial counts of samples were
determined. Samples were vacuum packaged and stored in refrigeration, and
chemical and microbial analyses were performed throughout storage. The pH
of samples decreased during storage, and the sample having 2% salt and
500-ppm ascorbic acid had the greatest pH decline. TBA values generally
increased (P < 0.05) with storage time. Samples having 2% salt + 500-ppm
ascorbic acid had the lowest TBA value. On a given storage day, samples
having 2% salt + 100-ppm sodium nitrite had lower microbial microbial count
than other samples, indicating the antibacterial effect of nitrite. A significant
storage time ¥ treatment interaction (P < 0.05) existed for almost all quality
parameters studied.

RESUMEN Propiedades antioxidantes de algunas plantas que crecen salvajes en Turquía. En este estudio, la actividad antioxidante de extractos metanólicos al 50% en agua de 38 plantas que crecen en la provincia turca de Afyonkarahisar fueron evaluados con al-gunos ensayos antioxidantes, incluyendo la actividad capta-dora de radicales libres y de peróxido de oxígeno (H 2 O 2) y la actividad quelatante de metales (Fe 2+). Los extractos meta-nólicos de frutas de las especies Cornus y Morus (activida-des captadoras de H 2 O 2 y DPPH y actividad quelatante de Fe 2+) y los extractos metanólicos de hojas de especies de Mentha (actividad captadora de DPPH) son los que mostra-ron una actividad mayor. Estas propiedades antioxidantes dependieron de la concentración de la muestra. PALABRAS-CLAVE: Actividad antioxidante-Actividad quelatante-Captadores radicalarios-Extractos-Plantas medicinales y aromáticas. SUMMARY Antioxidant properties of some plants growing wild in Turkey. In this study, the antioxidant activity of 50% aqueous methanol extracts of 38 plants growing in the Afyonkarahisar province of Turkey were evaluated by various antioxidant assay, including free radical scavenging, hydrogen peroxide (H 2 O 2) scavenging and metal (Fe 2+) chelating activities. The methanolic fruit extracts of the Cornus and Morus species (H 2 O 2 and DPPH scavenging activities, Fe 2+ chelating activity) and the methanolic leaf extracts of the Mentha species (DPPH scavenging activities) examined in the assay showed the strongest activities. These antioxidant properties depended on the concentration of samples.

In this study, the antioxidant contents of Ribes multiflorum Kit. Ex Roem. & Schult (black currant) which was grown in Emir and Kumalar mountains in Afyonkarahisar were investigated. Ribes multiflorum Kit. Ex Roem. & Schult is found on 1700 m at Emir Mountain in Dumluca, on 1400 and 1600 m at Kumalar Mountains in Basören. Antioxidant activities of samples were determined by free radical scavenging effect, chelating activity with Fe +2 and H 2 O 2 inhibition methods. The lower EC 50 value, the higher antioxidant power. In the presence of metal ions, super reactive hydroxyl radical may be formed by Fenton reaction. The findings obtained in the present work indicated that the Ribes multiflorum are potential source of natural antioxidant. Their antioxidant properties probably depend on concentration of sample.

The effects of packaging method (aerobic packaging (AP), vacuum packaging (VP) or modified atmosphere packaging (MAP)), the form of pastirma (sliced or non-sliced) and storage time (0, 15, 30, 60, 90 or 120 days) on the chemical, microbiological and sensory properties of a Turkish pastirma were investigated. Overall, MAP preserved chemical, microbiological and sensory properties of Turkish pastirma better than AP or VP. Very high correlation coefficients (almost all >0.90) were observed between subjective quality parameters (sensory properties) and objective quality parameters (TBARS, hexanal content, L * , a * , and b *), which suggests that sensory panel was able to determine the quality changes over storage time precisely. Based on the results of this study, MAP should be the preferred choice of packaging in order to preserve overall quality of Turkish pastirma and its implication for pastirma packaging may increase pastirma's current share in the processed meat product market.