Search

Summary: In developing countries, fresh fruit juices are prepared and sold without ongoing assessment of the quality and safety of mulberry and carrot juices. Therefore, most fruit juices offered for consumption had high microbial content. This investigation was performed to indicate the efficacy of low concentrations of Cinnamomum verum essential oils (CEO) in the inactivation of E. faecalis and S. aureus in carrot juice and white mulberry juice and the impact on the sensorial characteristics of the juices. CEO antimicrobial activity can prevent the growth of Staphylococcus aureus and Enterococcus faecalis at 12 and 4 °C in juices. For the MIC and MBC concentrations, CEO exhibited higher antibacterial effects against S. aureus and E. faecalis. A higher number of pathogens were inactivated at 12 °C than at 4 °C. Cytoplasmic membrane permeability plays a vital role in the CEO bactericidal action. CEO can be recommended to extend the shelf‐life of juices by retaining the sensorial quality and inactivating pathogenic microorganisms, which provides a reference for practical production and application. [ABSTRACT FROM AUTHOR]

Gaziantep (in Turkey) is one of the oldest cities in the World, in which the history of winemaking and viticulture began in ancient ages. It is home to wild white grapes Vitis vinifera Dökülgen and Paf. Three young white wines were produced from these two grapes. Ten phenolics and some chemical characteristics were quantitatively detected in the white wines and musts depending on white wine processes. Phenolic compounds significantly (p<0.05) increased during the fermentation process. After aging, (+)- catechin and procyanidin B2 contents of white wines were ranged from 1.12 to 1.35 and from 60.69 to 69.02 mg/L respectively. After aging, the quercetin, rutin and myricetin contents of white wines-1, 2 and 3 were ranged from 0.47 to 0.59, from 0.28 to 0.32 and from 0.11 to 13 mg/L respectively. White wines represented with abundant flavanols, tyrosol and chlorogenic acid produced from Dökülgen and Paf mixture with 7:3 ration. It was found that there is a significant difference between hydroxycinnamic acid and hydroxybenzoic acid content of white wines. Dökülgen and Paf white grapes contribute higher amount of phenolic characteristics, better acidity and sugar to white wine while Dökülgen grape contributed more sugar. [ABSTRACT FROM AUTHOR]

The research was performed to investigate the effect of high hydrostatic pressure low temperature (HHPLT) on Listeria innocua in Ringer's solution (RS) and raw milk (RM). The physicochemical properties of RM were studied at 300 MPa and 10 °C. Compared with the control, protein and lipase activities were reduced at HHPLT in RM. The L-values (luminance) of LHPLT applied RM were significantly (P < 0.05) decreased for colour Pressure application at 300 MPa for 90 min totally inactivated L. innocua at –20 °C in both RS and RM. L. innocua showed resistance to low pressure (200 MPa) in RM. Overall, increasing the pressure with applications at –20 and –30 °C resulted in a higher (P < 0.05) inactivation of L. innocua than at 10 and 20 °C. HHPLT applications to frozen RM resulted in the retention of textural characteristics. [ABSTRACT FROM AUTHOR]

The subject of this study was to investigate lactic acid bacteria (LAB) and yeasts microbiota of traditional sourdough (n = 36) and to indicate characteristics of enriched sourdough that is produced from combinations of isolates. A total of 60 LAB and 40 yeasts were identified from sourdough by matrix-assisted laser desorption ionisation--time-of-flight mass spectrometry (MALDI-TOF MS) analysis. The dominant LAB microflora was Lactobacillus brevis (43.33%), Pediococcus acidilactici (21.67%) and Lactobacillus plantarum (18.33%). The dominant yeasts microflora was Saccharomyces cerevisiae (27.5%), Pichia kudriavzevii (25.0%) and Kluyveromyces marxianus (12.5%). The sourdough prepared with the combination of L. brevis, Leuconostoc mesenteroides, P. acidilactici and S. cerevisiae, K. marxianus showed the best physicochemical and microbiological properties while that with L. plantarum, L. brevis and P. kudriavzevii, Wickerhamomyces anumalus was the poorest. LAB and yeasts in the sourdoughs were ranged from 6.58 log CFU g-1 to 9.12 log CFU g-1 and from 6.12 log CFU g-1 to 7.88 log CFU g-1, respectively. Various chemical parameters such as pH, total titratable acidity (TTA), ethanol, and sourdough volume were differ depending on the type of microbial species. TTA was more pronounced in the sourdoughs produced with homofermentative LAB. Yeasts and LAB were dominated during continuous enriching of sourdough, supporting an important role during fermentation. [ABSTRACT FROM AUTHOR]

The increase in cheese production, sale, and consumption due to the settled lives of societies has led to an increase in cheese‐related diseases. It has become essential to better understand cheese‐borne diseases and to develop control measures. In this study, cheese‐related diseases and precautions taken in the Ottoman Empire from the 19th to the 20th centuries were investigated in Ottoman archival sources. Of these documents, cheese spoilage was detected in 12 and cheese‐related disease in 9. Cheeses that caused diseases or disorders in the relevant period were called spoiled cheese. One document states that a person died of a cheese‐borne illness. Cheese poisoning occurs mainly from unsalted, fresh cheeses. It has been determined that tin‐free copper pots were used in cheese production and sales and covered with herbs such as hemlock during maturation. In the relevant period, microbiological and chemical analyses of cheeses in terms of health were carried out in food control laboratories. Since the mercury chloride solution is used to disinfect animal udders, it has been stated that it contaminates the milk used in cheese production. Authorities have requested a boric acid solution (5% boric acid in hot water) instead of this solution for udder disinfection. In the Ottoman Empire, it was requested to take necessary sanitation and hygiene measures to prevent spoilage and cheese‐related diseases in the production areas or sales places of cheese. Clean and tinned containers should be used in cheese production, storage, and sale, and poisonous herbs should not be used during cheese ripening. It was also essential to analyze them in laboratories at internal and external customs. Knowing the precautions taken in the past to prevent the deterioration of food or the occurrence of diseases has led to modern food safety practices being applied today. [ABSTRACT FROM AUTHOR]

In total, 240 samples were randomly collected from different locations in Gaziantep Turkey, 120 of which were unpacked and packed ground red chili pepper and 120 of which were unpacked and packed pistachio nuts. All samples of the unpacked and packed ground red chili pepper were found to be contaminated with aflatoxins and aflatoxin B1. Three (9.4%) of the packed ground red chili pepper samples were over the legal limit of aflatoxin B1 while 55 (62.5%) of the unpacked samples were over the legal limit. Thirty four (36.2%) of the unpacked pistachio nut samples were contaminated with aflatoxins. There is a need to strictly prohibit the use of batches of ground red chili pepper and pistachio nuts containing aflatoxins. [ABSTRACT FROM PUBLISHER]

Food safety can be defined as the application of principles and measures to provide healthy and safe food products during production, storage, transportation, distribution, and consumption. Food can be exposed to many chemical contaminants due to increasing industrial development and environmental pollution. The use of food additives has been increased due to increasing food production to benefit the increased human population. Food safety management systems have been developed to produce healthy and safer foods and to ensure sustainability of competition. The Turkish Standardization Institution (TSE) prepared the TSE 13001 standard based on the principles of the Hazard Analysis and Critical Control Points (HACCP). The HACCP system provides production of good quality and safer foods under international standards from farm to fork. In Turkey, in the field of food security, full responsibility has been given to the Ministry of Agriculture and Rural Affairs. [ABSTRACT FROM AUTHOR]

The inactivation kinetics of high hydrostatic pressure for Salmonella typhimurium (KUEN 137) inoculated in tryptone soy broth (TSB) and foods (raw milk and orange juice) were studied from 250 to 400 MPa, 15-45 °C and pH adjusted from 5.0 to 7.0. The rate of inactivation of S. typhimurium during the initial 10 min was far greater than during the remaining treatment time. The inactivation of S. typhimurium showed two-phase inactivation (fast to slow). Decimal reduction times (D value) for S. typhimurium in the second phase were 4.61, 2.59, 2.09, and 1.80 min at 250, 300, 350, and 450 MPa, respectively, in TSB after 10 min (second phase). D values were 1.75 and 1.50 min for S. typhimurium in milk and orange juice, respectively, at 300 MPa (second phase) and the k values were 1.32 and 1.54 min-1, respectively (second phase). The rate of inactivation increased in increasing temperature and there were significant (P<0.05) reductions in the S. typhimurium at treated temperatures, pressures, and pH. The use of inactivation could be beneficial to the food industry for optimizing process conditions. [ABSTRACT FROM AUTHOR]

Inactivation curves of Salmonella typhimurium under high-hydrostatic pressures (HHPs) (200, 250, 300 and 350 MPa) at different temperatures (15, 25, 35 and 45°C) in tryptone soy broth were analyzed using the modified Gompertz model. The phase of disappearance (time for inactivation of all cells, λ) and the inactivation rate (μ) of S. typhimurium were inversely related, Inactivation rates of S. typhimurium were higher (P <0.05) at 45°C than 15, 25 and 35°C under HHPs from 200 to 350 MPa. The μ values were -2.66, -6.06, -7.67 and -7.99 min-1 at 200, 250, 300 and 350MPa HHP treatments, respectively, at 45°C. A negative μ value (always negative) indicates that an increase (become more negative) in μ with increasing pressure or temperature is related to the S. typhimurium inactivation process. The μ values were also increased with increasing temperature from 15 to 45°C at same treated pressures. Increased pressure and temperature had significant effects on the survival of S. typhimurium. The temperature dependence of the inactivation rate constant was analyzed based on the Arrhenius, linear and square-root models. The pressure sensitivity (low Eμ) determined based on the Arrhenius model was lower at high pressure. Eμ (activation energy) value was 1.94 kJ/mol at 350 Mpa, and 42.88, 12.99 and 3.73 kJ/mol at 200, 250 and 300 MPa, respectively. Results of this study enable the prediction of microbial inactivation exposed to HHPs at different temperatures. [ABSTRACT FROM AUTHOR]

Sucuk (a kind of dry-fermented Turkish sausage) dough was inoculated with Staphylococcus aureus at a level of 3.74 log colony forming unit (cfu) g-1 and manufactured in the presence of spices and addition of lactic acid bacteria (LAB) and with and without essential oil of Thymbra spicata. All samples were analyzed for S. aureus, aerobic plate count (APC), LAB and pH during manufacturing and storage. Results showed that counts of S. aureus were decreased by 1.97 and 3.71 log units after manufacturing in sucuks made with LAB and LAB + essential oil respectively, and APC by 1.70 and 2.74 log unit, respectively. pH dropped more rapidly in sucuks made using LAB during fermentation time. pH values was decreased in 3 days of fermentation to the lowest point of 4.82 and 4.92 in sucuks made with LAB and LAB + essential oil, respectively. This was 5.37 for control sucuk (made without LAB). The low pH was effective in the inactivation of pathogenic bacterium and APC in sucuks. Cells were decreased during fermentation, ripening and storage periods of sucuk. Essential oil of T. spicata was showed additional antimicrobial effect on S. aureus and APC in sucuks beside low pH and ingredients (spices and nitrate). [ABSTRACT FROM AUTHOR]

The modeling of sucuk (Turkish dry-fermented sausage) production techniques on the survival of Listeria morlorytogenes, aerobic bacteria (AB), lactic acid bacteria (LAB), and yeasts and molds (YM) during ripening and storage periods were studied. Effect of L. monocytogenes initially contaminated level (low, medium and high contaminated levels) with sucuk dough was also studied. Survival data were analyzed by non-linear regression of modified-Gompertz and logistic equations to generate "best fit". L. monocytogenes was immediately reduced during ripening period (during 15 days) in sucuks produced from both controlled and traditional methods. The reduction in the number of L. monocytogenes was also continued during storage periods (15 days). There was no survival of L. monocytogenes after 25 days (10 days storage) in sucuks contaminated with low level of L. monocytogenes ripened in both methods. AB, LAB and MY were also reduced during ripening and storage periods. Parameters of non-linear modified-Gompertz and logistic models of L. monocytogenes, AB, LAB and YM in sucuks ripened in controlled and traditional methods were matched in a satisfactory way during ripening and storage periods. Both the modified-Gompertz and logistic models showed good fit to all the survival curves as assessed using the root mean square error (RMSE) and the correlation coefficient (R²) between the experimental and predicted values but the modified-Gompertz model best fit (R² ⩾ 0.98) than the logistic model (R² ⩾ 0.96). As a consequence, the model provides parameters for different production methods in modified-Gompertz model against microorganisms. [ABSTRACT FROM AUTHOR]

Abstract: The effects of some commercial additives on the quality of sucuk (Turkish dry-fermented sausage) were investigated during the ripening and storage periods. Microbial, chemical and sensory changes were followed for 15 days of ripening and 36 days of storage. Aerobic plate count (APC) increased (P <0.05) from 5.19 to 6.09logCFU/g during the first 10 days of ripening and afterwards decreased (P <0.05) to 3.69logCFU/g. APC and lactic acid bacteria (LAB) changed significantly (P <0.05) with time and additives. LAB increased (P <0.05) from 4.62logCFU/g to about 5.47logCFU/g during the first 10 days of the ripening period and decreased to 1.79logCFU/g at the end of storage. Control sucuk without additives had the highest level of mould and yeast counts (5.09logCFU/g). TBARS values increased gradually (P <0.05) from 0.61 to 1.73mg/kg and tyramine concentrations varied from 56.8 to 419mg/kg. Control sucuk was found to have the lowest overall sensory quality (P <0.05), and nitrate/nitrite concentration increased (P <0.05) the overall sensory quality of the sausages. Pearson’s correlation test indicated that there was a link (P <0.01) between the overall sensory quality and pH, TBARS values, mould and yeast counts, and putrescine concentration. [Copyright &y& Elsevier]

Abstract: Hot pepper pastes were produced by various starter cultures (Saccharomyces spp., Streptomyces griseus), production techniques (traditional and vacuum), and with or without salt addition. They were stored at 37°C for 46 days. The pH values, acidity, brown pigment formation, aerobic plate count (APC), and mould and yeast counts were determined during the storage periods. The acidity and pH values of hot pepper pastes produced by the traditional technique did not change (P >0.05) during the storage periods. The pH values of hot pepper pastes produced by the vacuum technique decreased (P &#60;0.05) during the first days of the storage period after which increasing pH values (P &#60;0.05) were observed. The pH values of hot pepper pastes produced by the traditional technique were lower (P &#60;0.05) than the paste produced by the vacuum technique. Brown pigment formation in pastes produced by vacuum and traditional techniques were found to be in the range of 0.78–1.58 optical density (OD) and 7.51–9.52 OD, respectively. Addition of salt into pastes produced by the vacuum technique decreased (P &#60;0.05) the brown pigment formation. The starter culture had no any effect (P >0.05) on the brown pigment formation in pastes produced by both traditional and vacuum techniques. Traditionally produced hot pepper had a higher (P &#60;0.05) number of APC than the other two production techniques. Mold and yeast counts of hot pepper pastes decreased (P &#60;0.05) sharply during the storage periods. Addition of both 5% salt and starter culture had no significant effect (P >0.05) on the mold and yeast counts of hot pepper pastes. Also, the production technique did not change (P >0.05) the mold and yeast counts of hot pepper pastes. [Copyright &y& Elsevier]

The hot pepper pastes were produced by various production techniques (traditional, open pan and vacuum). They were stored at 37 °C for 46 days. The pH values, acidity, brown pigment formation, aerobic plate count (APC), and mold and yeast counts were determined during the storage periods. pH value of fresh hot pepper was about 5.20, and pH values were ranged between 4.08 and 4.56 after processing. Generally, pH values decreased (P<0.05) during the first 14 days of the storage in pastes produced by open pan and vacuum techniques and then increased (P<0.05). pH values of paste produced by traditional technique were lower (P<0.05) than the pastes produced by open pan and vacuum techniques, however, acidities of hot pepper pastes produced by traditional technique were higher (P<0.05) than the other techniques. Addition of 5% salt into pastes decreased (P<0.05) the pH values and prevented pH values increasing during the storage periods, but did not change (P>0.05) the acidity. Brown pigment formation in pastes increased (P<0.05) during the storage period. APC and mold and yeast counts of hot pepper pastes decreased gradually (P<0.05) during the storage periods. Traditionally produced hot pepper had a higher (P<0.05) APC number than the other two production techniques. Traditionally produced hot pepper paste was found to be best with respect to flavor scores. Color scores of paste produced by vacuum techniques were found to be more acceptable than the other techniques. [Copyright &y& Elsevier]

The effects of starter cultures and additives on the quality of Turkish style sausage (sucuk) were investigated during ripening and storage. Total aerobic plate counts (aerobic bacteria), mould and yeast counts, pH, thiobarbituric acid (TBA) value and biogenic amine formation were followed. Aerobic bacteria increased (P<0.05) during the first 10 days of ripening to 9.26 log CFU/g and they decreased (P<0.05) to 5.70 at the end of the storage. Larger reductions (P<0.05) were observed in sausages made with high levels of potassium sorbate, nitrite and nitrate than in those containing low levels of additives and those without additives at the end of storage. During the first 3 days of ripening, the pH values of all sausages decreased (P<0.05) from 5.98 to about 4.53. Later, the pH values increased slowly, due to decomposition of acids to an approximately constant value of about 5.20. TBA values were higher (P<0.05) in the sausages made without additives than in the others. Sausages prepared using high concentration of additives had lower (P<0.05) concentrations of biogenic amines than the others. Addition of starter culture with high concentration of additives (nitrite, nitrate, α-tocopherol, ascorbic acid, potassium sorbate, potassium pyrophosphate and di-potassium hydrogenphosphate) decreased the formation of biogenic amine. [Copyright &y& Elsevier]

Citric acid production and biomass formation in submerged culture using Aspergillus niger from undersized semolina, with and without methanol, were analyzed using Gompertz, Logistic, Schnute, and Boltzman''s models. They were compared statistically by using the F-test. Three-parameter models were statistically sufficient to describe the citric acid and biomass formation of A. niger. Citric acid and biomass formation rates (μ) ranged from 0.099 to 0.412 g/l/day and 0.173 to 0.744 day−1, respectively. The lag phase duration increased from 0.387 to 3.281 and 0.087 to 0.824 days, respectively. Increased methanol concentration and the initial pH values of the medium had significant effects on the citric acid and biomass formation. [Copyright &y& Elsevier]

This paper presents the triaxial testing results of a study in which biocementation processes were employed to observe the behaviour at small strains of sand matrix. Biocementation was achieved using the microorganism Sporosarcina pasteurii, an aerobic bacteria growth in natural soil deposits. The microbes were introduced to the sand specimens in a liquid growth medium with three different amounts of urea and dissolved calcium sources. Subsequent cementation treatments were passed through the specimen under confining pressure. The results were assessed by local strain measurements using LVDTs. A series of undrained compression triaxial tests indicate that at small strain levels the observed stiffness-strain behaviour of biocemented sand specimens appeared to be significantly high for all three treatment levels. The response of biocemented sands was found to be similar to that of calcite and lime cemented specimens, which represent conventional cementing agents. Scanning electron microscopy pictures and energy dispersive X-ray were taken to verify the formation of cement at three different concentrations. [ABSTRACT FROM AUTHOR]

In this study, 180 red chilli pepper (RCP) berry samples were obtained from two different croplands of Gaziantep and Kahramanmaraş (Turkey) in August, September and October. RCP berry samples were dried under sunlight and grinded. Ground red chilli pepper (GRCP) samples were analysed for aflatoxins (AFs, sum of B1, B2, G1and G2) and AFB1contamination. According to the results, in 49 of 180 samples, AFB1and in 37 samples, AFs were higher than legal limits. The lowest amounts of AFs and AFB1were obtained in August and the highest amounts in October.χ2analysis showed that there were no significant differences (p > 0.05) between cities among 3 months according to number of samples with AFs and AFB1above legal limits. According to the Duncan multiple-range test, there was no significant difference between all months. Strict measures are necessary to produce high-quality GRCP. RCP berry must be treated to reduce moulds before production of GRCP. [ABSTRACT FROM AUTHOR]

The aim of this research was to analyze and model the combined effect of pressure and temperature upon Aspergillus ochraceus spores exposed to high pressure carbon dioxide (HPCD) treatment and to estimate the kinetic parameters. Lately, many empirical or semi-empirical mathematical models were presented and discussed for different microorganisms, mainly bacteria, demonstrating an increased need for tools able to quantify the parameters of the microbial inactivation. A. ocharaceus HPCD inactivation was adequately described by first order reaction kinetics and a synergic effect of pressure and temperature was noticed for the experimental range where pressure varied from 5.4 to 7.0 MPa and temperature varied from 30 to 50 °C. The decimal reduction time (D) ranged from 47.07 min at 5.4 MPa and 30 °C to 5.04 min at 7.0 MPa and 50 °C. In this study three mathematical models were evaluated in order to find the best one that describes accurately the influence of pressure and temperature on the studied microbial response. An empirical exponential equation, that described pressure and temperature influence in the form of a polynomial equation, was found to best describe the dependence of A. ochraceus HPCD inactivation in the range 5.4-7.0 MPa and 30-50 °C. This work adds insight to moulds inactivation at the already existing body of knowledge on bacteria inactivation with HPCD and provides support to potential industrial applications of the minimal-thermal methods that combine high pressure and mild temperature with carbon dioxide for different food matrixes. [ABSTRACT FROM AUTHOR]

In this study, inhibitory effects of bayleaf, rosemary, sage, and thyme hydrosols on the growth ofStaphylococcus aureusinoculated on fresh-cut apples were investigated using several sigmoidal models (modified Gompertz, logistic, Richards, Stannard, and Whiting and Buchanan). In addition, these models were compared to describe the inactivation ofS. aureusby fitting the experimental data using nonlinear models and various statistical parameters (the mean percentage error, the mean bias error, the root mean square error, the modeling efficiency, and chi-square parameters) as well as determination of coefficient (R2). The modified Gompertz, logistic, and Stannard models exhibited better fits than Richards and Whiting and Buchanan models regarding these statistical parameters. Rosemary and thyme hydrosols were found to be the most efficient sanitizers in reducing theS. aureusnumbers. Results demonstrate that predictive models could be utilized for describing the inactivation or survival ofS. aureuson fresh-cut apple with the effects of the treatments with plant hydrosols. [ABSTRACT FROM PUBLISHER]