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402 samples of 22 species of cultivated and wild fresh mushrooms sold in retail markets and supermarkets in Zaragoza (Spain) were studied to quantify their microbial load (mesophilic aerobic microorganisms, Pseudomonas genus, Enterobacteriaceae, lactic acid bacteria, total and thermotolerant coliform bacteria, Escherichia coli, yeasts and moulds) and to investigate the presence of E. coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus and Yersinia enterocolitica. The total microbial counts ranged from 4.4 to 9.4 log cfu/g, the genus Pseudomonas being the most prevalent with counts from 3.7 to 9.3 log cfu/g and Auricularia auricula-judae the species with the highest microbial load (9.4 log cfu/g). No significant differences (p > 0.05) were detected between mean counts of wild and cultivated species in all the microbial groups studied. The microbiological safety level of the cultivated mushrooms was excellent since no pathogens were isolated, and the microbial counts of indicator microorganisms were low, being detected in only half of the species. Salmonella spp, E. coli O157:H7 and S. aureus were not isolated from any sample, Y. enterocolitica was detected in only four samples of wild mushrooms whereas twenty-six (6.5%) were positive for L. monocytogenes, their occurrence being relatively high in Calocybe gambosa (40%), Hygrophorus limacinus (40%) and Tuber indicum (100%). These results suggest that a strategy to reduce bacterial populations, and to improve the microbiological safety of some species of fresh mushrooms, should be investigated. 相似文献
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M.J.M. van den Broek D.A.A. Mossel H. Mol 《International journal of food microbiology》1984,1(2):53-61
A total of 242 samples of ready-for-sale fish fillets of validated good sensory quality was examined for colony counts at 20, 30 and 37°C, Enterobacteriaceae at 37°C, Escherichia coli, Salmonella and Vibrio parahaemolyticus in 10 g aliquots. Staphylococcus aureus and yeast and mould propagules. Gram negative pathogens were not detected in any sample. The following reference values were found attainable: colony counts at 30°C, 106 g?1; E. coli 10 g?1; S. aereus 102 g?1; yeast and mould propagules 104 g?1. These reference values include, as customary, a tolerance of about 20% of samples exceeding the stated levels without, however, reaching the next log10 level. 相似文献
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K.I. Ereifej 《International Journal of Food Properties》2013,16(4):803-811
Goat's milk from three phenotypes: Shami, Local, and Mixed was collected during three lactation periods in 2002. The milk was analyzed for moisture, protein, fat, ash, and lactose content. Also milk was examined for yeast, mold and bacterial content. Cheddar and white cheese were manufactured from goat's bulk milk and examined for chemical composition and evaluated for color, taste and flavor, appearance, and texture and aroma. Results showed that the chemical composition of goat's milk varied significantly during the whole year and also among the three goat phenotypes. Local goats produced milk at the first lactation period with highest (44.6%) fat content: the lowest fat content was 29.8% for the Mixed color phenotype at the end of the year. Protein showed the same trend. Shami goat produced milk lower in lactose and ash content than the mixed color breed, whereas the Local (black) produced milk having intermediate content of lactose and ash. Cheddar and white cheese were highly acceptable. Their composition varied—cheddar cheese was higher in protein and NSF but slightly lower in fat content. White cheese retained more lactose. Goat's milk of Shami, Local (black) and Mixed color phenotypes were found to be highly contaminated with bacteria and mold due to lack of hygiene. Milk contained low number of pathogenic bacteria. Using a pasteurization temperature at 73°C for 16 seconds was found to eliminate them. 相似文献
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Kashar cheese, traditionally produced, is a popular dairy product in Turkey. Kashar cheese—a hard cheese—is frequently contaminated with mould. Potassium sorbate can be used for preservation of Kashar cheese. In this article, the effect of potassium sorbate on the microbiological characteristics of Kashar cheese was studied. It was found that the microbial counts at stored at 4 ± 0.1°C for 12 and 24 hours were not different from that of fresh milk samples. The means of total aerobic mesophilic bacteria (TAMB), lactic acid bacteria (LAB), coliforms, Staphylococcus aureus, proteolytic microorganisms, lipolytic bacteria, psychrotrophic bacteria and yeast-moulds in the cheese samples were determined as 4.3 × 107, 2.1 × 105, 3.5 × 10, 1.2 × 10, 4.5 × 105, 5.6 × 104, 1.7 × 103, and 4.8 × 104 cfu/g, respectively. The addition of potassium sorbate to Kashar cheese decreased the coliform and yeast-mould counts. The yeast and mould counts of cheese samples with added dry potassium sorbate were lower than that of fluid potassium sorbate. 相似文献
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The determination of aflatoxins in spices by immunoaffinity column extraction using HPLC 总被引:1,自引:0,他引:1
Cavit Bircan 《International Journal of Food Science & Technology》2005,40(9):929-934
Seventy‐five samples of different spices marketed in Turkey were purchased from bazaars, herbal shops and supermarkets. Equal amounts of paprika, chilli, black peppers and cumin were purchased and used to test and compare the amount of aflatoxin contamination. Two different analytical methods were examined for their efficacy by adding a known amount of aflatoxin to the blank samples of paprika. Twenty‐seven paprika, all the chilli powder and four ground black pepper samples were contaminated with aflatoxin B1 in the range of 0.5–116.4, 1.6–80.4 and 0.3–1.2 μg kg?1 respectively. Twenty‐three (30%) paprika and chilli powder samples were above the regulatory limits used in the European Union. No aflatoxin contamination was detected in the cumin samples at a detection limit of 0.2 μg kg?1. 相似文献
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The work presents some results from the evaluation of microbiological (total bacterial count, coliform bacteria, moulds and yeasts) and sensory (shape, odour, colour, taste, consistency, crust, soft inside, etc.) quality and of the aw value and pH during the 90‐day storage (interval of 0, 30, 45, 60, 75 and 90 days) under laboratory conditions at 20 ± 2°C in eight types of the bakery croissant‐type product with the nougat cream differing by the type of dough (brioche, croissant( aw value of the cream, and by the presence or absence of sorbic acid in the spirit spray applied onto the surface of products. The above‐indicated parameters were examined also in the nougat cream samples (on the zero and 90th day of storage). The chosen quality parameters permitted the level of the durability influence of croissants depending on external (sorbic acid) as well as internal (recipe, aw) conditions to be estimated. 相似文献
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IOANNA‐ARETI ASTERI NANCY KITTAKI EFFIE TSAKALIDOU 《International Journal of Dairy Technology》2010,63(2):234-242
A blend of four wild strains of lactic acid bacteria, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactobacillus paracasei subsp. paracasei and Enterococcus faecalis, was used as starter to produce a goat’s milk soft cheese. The cheese was analysed microbiologically, physicochemically and organoleptically through a 30‐day period of ripening. Counts of the starter cultures increased in the first 24 h and then remained stable during ripening. Yeasts and coliforms were found at low numbers initially and gradually decreased to undetectable levels. Micrococcal counts were high throughout ripening. The end product was a soft cheese characterised by a mild, aromatic taste as well as a smooth structure. 相似文献
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The objectives of this study were to determine basic composition, aroma and sensory characteristics of Circassian cheese. Seven Circassian cheeses were provided by local producers. Aroma compounds were extracted by using solid‐phase microextraction procedure and determined by gas chromatography‐olfactometry system. Water‐soluble, trichloroacetic acid‐soluble and phosphotungstic acid‐soluble nitrogen fractions ranged between 2.30–29.35%, 2.48–9.96% and 3.33–6.26%, respectively. Diacetyl, butyric acid, 2‐acetyl‐1‐pyrroline, 1‐octen‐3‐one and methional were identified at high intensities in cheeses. In addition, ‘cooked’, ‘whey’, ‘creamy’ and ‘fermented’ were defined as characteristic flavour terms for Circassian cheeses. 相似文献
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K. Evert-Arriagada M.M. Hernández-HerreroB. Juan B. GuamisA.J. Trujillo 《Journal of food engineering》2012
The effect of high pressure (HP; 300 and 400 MPa for 5 min at 6 °C) on physico-chemical, microbial, color, texture and sensorial characteristics of starter-free fresh cheeses stored at 4 and 8 °C was studied. Physico-chemical parameters considered were total solids, fat, total protein, pH, whey loss and water activity. The microbiological quality was studied, on cheeses stored at 4 and 8 °C, by enumerating aerobic mesophilic bacteria, lactococci, psychrotrophic bacteria, Enterobacteriaceae, Escherichia coli, molds and yeasts. Cheeses treated at 300 and 400 MPa, stored at 4 °C, presented a shelf-life of 14 and 21 days, respectively, compared to untreated control cheese, which presented a shelf life of 7 days. On the other hand, HP treatments modified the texture (more firm) and color (more yellow) compared to control cheeses. These changes were detected by instrumental and sensory analysis. 相似文献
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Fresh cheese composition was assessed by measuring ultrasonic velocity in cheese and cheese blends at different temperatures. Twenty types of commercial, fresh cheeses with fat contents ranging from 0.2% to 17.6% w.b. were analyzed. Ultrasonic velocity was not only heavily dependent on the composition of the cheese but also on its structure. Based on the different effect temperature has on velocity in water and fat, a semi-empirical model was used to estimate the cheese composition from velocity measurements at six temperatures ranging from 3 to 29 °C. The model provided good results for the assessment of the fat (R2 = 0.984/0.996; RMSE = 4.6/1.1 for whole and blended cheese, respectively) and water (R2 = 0.964/0.995; RMSE = 6.5/0.7 for whole and blended cheese, respectively) content. The ultrasonic measurements could be carried out during the cooling process that takes place after curdling and used as a quality control tool to detect process anomalies in-line. 相似文献
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Six strains of non-starter lactic acid bacteria (NSLAB) were used to extend the shelf-life of the fresh cheese Tosèla manufactured with pasteurised cows’ milk. The acidification kinetics of three Lactobacillus paracasei, one Lactobacillus rhamnosus and two Streptococcus macedonicus were studied in synthetic milk medium. Lb. paracasei NdP78 and NdP88 and S. macedonicus NdP1 and PB14-1 showed an interesting acidifying capacity and were further characterised for growth in UHT milk and production of antimicrobial compounds. Lb. paracasei NdP78 and S. macedonicus NdP1 grew more than 2 log cycles in 6 h. Lb. paracasei NdP78 was also found to produce a bacteriocin-like inhibitory substance (BLIS) active against Listeria monocytogenes. The four NSLAB strains (singly or in combination) were used to produce experimental pilot-scale cheeses which were compared by a panel. The cheese manufactured with the mixed culture Lb. paracasei NdP78 - S. macedonicus NdP1 was the most appreciated for its sensory properties. The cheeses produced at factory-scale showed higher concentrations of lactobacilli (7.90 log CFU/g) and streptococci (6.10 log CFU/g), but a lower development of coliforms (3.10 log CFU/g) and staphylococci (2.78 log CFU/g) than control cheese (4.86, 4.89, 4.93 and 5.00 log CFU/g of lactobacilli, streptococci, coliforms and staphylococci, respectively) processed without NSLAB addition. The food pathogens Salmonella spp. and Listeria monocytogenes were never detected. The dominance of the species inoculated was demonstrated by denaturing gradient gel electrophoresis (DGGE), whereas strain recognition was evaluated by randomly amplified polymorphic DNA (RAPD)-PCR. From the results obtained, Lb. paracasei NdP78 and S. macedonicus NdP1 were able to persist during the storage of Tosèla cheese and their combination influenced positively the sensory characteristics and shelf-life of the final product. 相似文献
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辣椒籽提取物抗氧化活性研究 总被引:1,自引:0,他引:1
用不同溶剂提取辣椒籽中的抗氧化物质,从还原能力、抗脂质体氧化和对Fenton体系产生的羟自由基的清除效果等方面对辣椒籽提取物的抗氧化活性进行了试验研究和评价。结果表明:辣椒籽提取物具有较强的还原能力,对脂质体氧化、Fenton反应产生的羟自由基均具有抑制作用或消除作用,优于同浓度的Vc和VE的效果或基本相当,这表明辣椒籽提取物是一种优良的天然抗氧化剂和自由基消除剂,而且不同溶剂的辣椒籽提取物的抗氧化作用效果不同,其中脱脂甲醇提取物>甲醇提取物>脱脂水提取物>Vc>石油醚提取物>VE。 相似文献
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Enzyme-modified cheeses (EMCs) are used to impart flavour to imitation cheese products. Cheeses (pH 6 or 5.5) were formulated with 5% w/w EMC, having low, medium or high levels of lipolysis and were examined by a sensory panel. Free fatty acid analyses were performed using SPME/GC. The flavour profile of the flavoured cheeses was affected by EMC composition and pH of the cheese base. Cheeses at a pH of 6.0, flavoured with low lipolysis EMCs, were described as ‘bland’. Lowering the pH of the cheese matrix to 5.5 appeared to increase the flavour intensity of the cheese flavoured with low lipolysis EMC and panellists ranked this cheese the highest, describing its flavour as ‘well-balanced and ‘cheesy’. This study shows that the flavours of imitation cheeses are influenced by the level of lipolysis of the EMCs used to flavour them and also by the pH of the cheese base. 相似文献
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The yield and sensory properties of reduced-fat Minas Frescal cheese made from low concentration factor (CF) retentates were studied. Three different CFs were tested (1.2, 1.5 and 1.8). The chemical compositions of the milk, retentate, whey and cheese were determined, as well as the cheese yield. The cheese moisture content decreased with increasing CF. The cheese yield was significantly dependent on the CF in the same direction as the moisture content. Despite compositional differences among the samples, only the cheese made with a CF of 1.8 presented low sensorial acceptance. CF 1.2 was found to be the optimum value for reduced-fat Minas Frescal cheese manufacture in the CF range studied. 相似文献
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FILIZ YILDIZ ATILA YETISEMIYEN EBRU SENEL FÜGEN DURLU‐ÖZKAYA SEBNEM ÖZTEKIN EBRU SANLI 《International Journal of Dairy Technology》2010,63(4):575-580
Civil cheeses were purchased from urban vendors in the city centre of Erzurum, Turkey. The biogenic amine contents of the cheeses and their microbiological and chemical properties were determined. It was found out that biogenic amine concentrations of the samples were not exceeding the toxic doses‐values. Total aerobic mesophilic bacteria, lactic acid bacteria and Enterobacteriaceae spp. were investigated as microbial analyses in the samples while several chemical analyses were executed. Statistical analyses were carried out for the determination of the relationship between the chemical properties and the biogenic amine contents of samples, and the existence of microorganisms and biogenic amines. 相似文献
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Microbial diversity in milk and in cheese itself affects the biochemical and sensory characteristics of artisanal cheeses. In this study, the microflora of Sepet cheese, which is a traditional artisanal cheese in Turkey, was investigated. Average lactococci, lactobacilli, enterococci, yeast, mould, coliform, psychrotrophic and total aerobic bacteria, presumptive Staphylococcus aureus counts were; 7.31 ± 1.08, 7.19 ± 1.02, 6.84 ± 0.92, 3.19 ± 1.40, 0.84 ± 0.89, 2.18 ± 1.81, 4.92 ± 1.15, 7.53 ± 1.13 and 1.25 ± 1.70 log cfu/g, respectively. Staphylococci, coliform and mould counts were less than 1.00 log cfu/g at the end of ripening, which was at around 6–8 °C for 3 months. According to phenotypic and genotypic identifications, isolates were closely related to Lactobacillus plantarum, Weisella confusa, Weisella paramesenteroides, Pediococcus pentasaceous, Enterococcus casseliflavus, Enterococcus durans and Enterococcus faceium. This study provides baseline data on the microflora of traditional artisanal Sepet cheese, which is a prerequisite for a successful scale up to industrial production. 相似文献
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Catarina Soares Ana Luisa Fernando Benilde Mendes António P L Martins 《International Journal of Dairy Technology》2015,68(3):409-419
São João cheeses with varying curd dry salting treatments were made with decreasing levels of salt (sodium chloride): 4 (control), 3, 2 and 1% (w/w), along with the salt‐free version. The cheeses were ripened at 11 °C over a 40‐day period, and the effect of lowering salt on the physicochemical, microbiological and sensory properties of the cheese was studied. Reduced salt resulted in a concomitant moisture decrease with protein increase, ash and sodium reduction among experimental cheeses at the same ripening day, but there were no significant differences in pH, acidity and fat, or in the microbiological quality. Triangle tests indicated perceptible differences between test and control cheeses at the level of 2% NaCl (w/w) or less, but not with the cheese salted with 3 g NaCl/100 g. Considering the sensory, the physicochemical and the microbiological results, the cheese formulated at 3% NaCl (w/w) (presenting a reduction of 25% in salt) is feasible on an industrial scale, being indistinguishable by the regular consumer. 相似文献