Güzin Kaban

Effects of starter cultures and nitrite levels on formation of biogenic amines in sucuk

The effects of starter cultures, starter A (Lactobacillus sakei+Staphylococcus carnosus) and starter B (Pediococcus acidilactici+Staphylococcus xylosus+Lactobacillus curvatus), nitrite levels (0, 75, and 150ppm) and ripening period on biogenic amine production were investigated in sucuk (Turkish dry-fermented sausage) production. Changes in biogenic amines, pH, water activity, moisture, non-protein nitrogen, nitrite and counts of lactic acid bacteria, Micrococcus/Staphylococcus, Enterobacteriaceae, and moulds-yeasts were determined. Ripening period had a very significant effect (P<0.01) on the all biogenic amines. Sausages produced by fermentation with starter cultures, as compared to natural fermentation (control), had lower amounts of putrescine, cadaverine and tyramine (P<0.05). Starter cultures A and B were found to have almost the same effect on the formation of biogenic amines. Use of nitrite in sucuk production affected the formation of biogenic amines except for spermidine and spermine (P<0.01). Lactic acid bacteria counts in the control group were lower than that of starter culture groups. Lactic acid bacteria, Micrococcus/Staphylococcus, and moulds-yeasts counts increased during ripening period while levels of species of Enterobacteriaceae decreased, which was also found to be under the detectable level (<100cfug(-1)), by day 3 of ripening.

Volatile Compounds of Traditional Turkish Dry Fermented Sausage (Sucuk)

The profile of volatile compounds of a typical Turkish dry fermented sausage (sucuk) were analyzed by gas chromatography/mass spectrometry (GC-MS) using a solid phase microextraction (SPME). The significant differences were found in the volatile profiles obtained in the five commercial brands analyzed. A total 92 compounds were identified. The volatile compounds were consisted of 5 acids, 7 esters, 10 aliphatic hydrocarbons, 7 alcohols, 5 aldehydes, 11 sulphur compounds, 2 ketones, 7 aromatic hydrocarbons, 27 terpenes, 2 nitrogen compounds, 3 phenols, and 6 compounds BCH. Terpenes were the chemical family with the highest proportion in four brands, ranged 56–76% of the total area of volatiles. Acids were major compounds (32%) in only one brand.

Effects of Corn Oil and Broccoli on Instrumental Texture and Color Properties of Bologna-Type Sausage

The effects of substitution of sheep tail fat with corn oil (50%) and the addition of broccoli (0, 5, or 10%) on the instrumental texture and color properties of bologna-type sausage were investigated during chilled storage (90 days at 4°C). Thiobarbituric acid-reactive substances and pH analysis were also carried out in fresh and storaged samples. The substitution of sheep tail fat by corn oil had very significant (P < 0.01) effects on the color scores (L*, a*, and b*) and textural properties of samples. The use of broccoli affected significantly (P < 0.01) color scores and hardness, gumminess, and chewiness values. Storage time had significant effects (P < 0.01) on hardness, springiness and cohesiveness, and color scores. The use of corn oil in bologna-type sausage decreased thiobarbituric acid-reactive substances value. However, at the end of storage this value was not over 15 μmol MDA/kg in sausage with animal fat. The pH values were not below 6.1 at the end of the storage.

Volatile compounds and some physico-chemical properties of pastırma produced with different nitrate levels

Objective The aim of the study was to evaluate the effects of different nitrate levels (150, 300, 450, and 600 ppm KNO3) on the volatile compounds and some other properties of pastırma. Methods Pastırma samples were produced under the controlled condition and analyses of volatile compounds, and thiobarbituric acid reactive substances (TBARS) as an indicator of lipid oxidation, non-protein nitrogenous matter content as an indicator of proteolysis, color and residual nitrite were carried out on the final product. The profile of volatile compounds of pastırma samples was analyzed by gas chromatography/mass spectrometry using a solid phase microextraction. Results Nitrate level had a significant effect on pH value (p<0.05) and a very significant effect on TBARS value (p<0.01). No significant differences were determined in terms of aw value, non-protein nitrogenous substance content, color and residual nitrite between pastırma groups produced by using different nitrate levels. Nitrate level had a significant (p<0.05) or a very significant (p<0.01) effect on some volatile compounds. It was determined that the amounts and counts of volatile compounds were lower in the 450 and especially 600 ppm nitrate levels than 150 and 300 ppm nitrate levels (p<0.05). While the use of 600 ppm nitrate did not cause an increase in residual nitrite levels, the use of 150 ppm nitrate did not negatively affect the color of pastırma. However, the levels of volatile compounds decreased with an increasing level of nitrate. Conclusion The use of 600 ppm nitrate is not a risk in terms of residual nitrite in pastırma produced under controlled condition, however, this level is not suitable due to decrease in the amount of volatile compounds.

Volatile profile and fatty acid composition of kavurma (a cooked uncured meat product) produced with animal fat combinations

ABSTRACT In this research, the effects of animal fat combinations (100% beef intermuscular fat, BIF); 100% beef kidney fat, BKF; 100% sheep tail fat, STF; 50% BIF + 50% BKF; 50% BIF + 50% STF; 35% BIF + 35% BKF + 30% STF) on volatile profile and fatty acid composition as well as selected physicochemical and sensorial properties of kavurma (a traditional Turkish cooked uncured meat product) were investigated. The group containing 50% BIF + 50% BKF had higher scores than other groups in terms of overall apperance, and taste-odor. The use of STF had a negative effect on sensory parameters. The lowest and the highest saturated fatty acid ratio were determined in the group with 100% STF and the group with 100% BKF, respectively. Among volatile compounds identified, aldehydes were the mostly found chemical group and hexanal was determined as major compound in all groups. As a result, the use of sheep tail fat increased unsaturated fatty acid ratio but negatively affected sensory properties of kavurma.

Volatile compounds of olive oils from different geographic regions in Turkey

ABSTRACT In this research, changes in volatile compounds of olive oil were investigated in terms of cultivar, harvest year, and geographic regions (Mediterranean, Aegean, Southeastern Anatolia, Marmara, and Black Sea) were investigated. Volatile compounds of olive oils were extracted by using solid-phase microextraction (SPME) method and were identified with gas chromatography–mass spectrometry. A total of 59 volatile compounds from seven different chemical groups including aldehydes, ketones, hydrocarbons, alcohols, esters, terpenes, and furans were identified. Aldehydes were detected as the major group in all geographic regions. Among aldehydes, trans-2-hexenal was found to be relatively higher. Alcohols and esters were determined as other important compounds. While many volatile compounds were affected by olive cultivar factor, this factor had no significant effect on esters. Principal component analysis showed that volatile compounds could play an important role in the separation of regions.

Effects of vacuum and high-oxygen modified atmosphere packaging on physico-chemical and microbiological properties of minced water buffalo meat

Objective In this study, the effects of vacuum (VP) and high-oxygen modified atmosphere (80% O2+20% CO2) packaging (HiOx-MAP) on physico-chemical and microbiological properties of minced water buffalo meat were investigated. Methods After minced meat preparation, samples were packaged under VP and HiOx-MAP and stored at 2°C±0.5°C for 14 days. Samples taken on certain days were subjected to total aerobic mesophilic bacteria, total aerobic psychrotrophic bacteria, lactic acid bacteria, Pseudomonas, Enterobacteriaceae and yeast-mold counts as well as pH, color (L*, a*, and b*) and thiobarbituric acid reactive substances (TBARS) analyses. Results In minced water buffalo meat packaged under HiOx-MAP, TBARS value exceeded 1 mg malondialdehyde/kg on the 4th day of the storage. In VP samples, TBARS value remained close to initial TBARS value during storage. According to the findings, a* value was determined to be high in the HiOx-MAP samples within initial days of the storage. However, no significant changes in a* value were observed in VP samples during storage. In contrast, the mean value of L* was detected as higher in HiOx-MAP sample than VP samples. The count of psychrotrophic bacteria increased more than that of mesophilic bacteria during storage. The growth of Enterobacteriaceae and Pseudomonas was delayed in both the packaging methods. However, lactic acid bacteria exhibited more growth in VP samples compared to MAP samples. Conclusion The lipid oxidation proceeded faster than expected in minced water buffalo meat packed with HiOx-MAP method. This situation adversely affected the a* value. On the other hand, similar microbiological results were obtained in both packing methods.

Staphylococcus xylosus ve Lactobacillus plantarum Suşlarının Sucuğun Duyusal Özellikleri ve Renk Değerleri Üzerine Etkileri / Effects of Staphylococcus xylosus ve Lactobacillus plantarum Strains on the Organoleptic Properties and Color Parameters of Sucuk

OZET : Arastirmada, geleneksel yontemle uretim yapan sucuk isletmelerinden temin edilen orneklerden izole edilen, Staphylococcus xylosus GM92 ve Lactobacillus plantarum GM77 suslarinin, sucugun duyusal ozellikleri ile renk degerleri uzerine etkileri incelenmistir. Kontrol ve muamele (S. xylosus GM92 + L. plantarum GM77) grubu olmak uzere iki farkli grup sucuk uretilmistir. Olgunlasmanin 3, 9 ve 14. gunlerinde sucuklarin renk degerleri olculmus, duyusal analizler ise 14. gunde gerceklestirilmistir. Ayrica olgunlasma sirasinda agirlik kaybi ve % nem degeri de tespit edilmistir. Suslarin L* degerinde onemli (P<0.05), a* degerinde ise cok onemli (P<0.01) etkiye sahip oldugu belirlenmistir. Olgunlasma suresi ise sadece a* degeri uzerinde onemli (P<0.05) etkide bulunmustur. Duyusal analizlerde butun parametrelerde starter kulturlu grup en yuksek puanlari almistir (P<0.05). Nem degeri ise her iki grupta da olgunlasmanin 7. gununde %40’ in altina dusmustur. Ayni olgunlasma gununde ortalama agirlik kaybi kontrol grubunda %32.53, starter kulturlu sucuklarda ise %34.88 olarak belirlenmistir. Anahtar Kelimeler: Sucuk; Staphylococcus xylosus; Lactobacillus plantarum; L*; a*; Duyusal analiz ABSTRACT : This study was conducted to determine the effects of Staphylococcus xylosus GM92 and Lactobacillus plantarum GM77 strains, which were isolated from the samples obtained from manufacturers who use traditional methods, on organoleptic properties and color parameters of sucuk. Two different groups of sucuk, control and treatment (S. xylosus GM92 + L. plantarum GM77) were manufactured. Color parameters were measured at the 3rd, 9th, and 14th days of the ripening period, organoleptic analyses were performed at the 14th day. In addition, weight loss and moisture (%) were also determined during the ripening. It was observed that the strains have a significant effect on L* value (P<0.05) and a very significant effect on a* value (P<0.01). The ripening period only has a significant effect on a* value (P<0.05). The group with starter culture was shown higher scores in all parameters of organoleptic analyses(P<0.05). The moisture was dropped to under 40% in both groups at the 7th day of the ripening. Average weight loss was 32.53% in control group at the same day of ripening while it was 34.88% in sucuk with starter culture. . Keywords: Sucuk; Staphylococcus xylosus; Lactobacillus plantarum; L*; a*; Organoleptic analysis