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1.
Changes in the physicochemical properties, mineral and heavy metal content and microbial flora of cacik samples were studied over a storage period of 30 d. The analysis results were in the ranges as follows: dry matter content 16.45–20.76%, fat 1.45–4.30%, protein 8.14–13.87%, total ash 0.96–4.19%, salt 0.25–3.15%. There were significant differences in dry matter, fat, salt, protein and ash content of the cacik samples (P < 0.05). There were significant differences in Ca, P, Na, Mg, Cu, Fe, Zn and Mn content of the cacik samples (P < 0.05). Total aerobic mesophilic bacteria (TAMB) and enterococci reached levels above 104 and 103 CFU g?1, respectively. Coliforms and Staphylococcus aureus were not detected in any of the cacik samples during the storage period. Lactic acid bacteria (LAB) on MRS and M17 agars were the dominant bacteria. The cacik samples had LAB counts up to 104.4 CFU g?1. Copyright © 2005 Society of Chemical Industry  相似文献   

2.
The objective of this study is to characterise the gross chemical and microbiological status and identify the volatile compounds of mouldy Civil cheeses. A total of forty‐one samples were surveyed, and gross compositional status of the cheeses was (as mean values): 6.5 for pH, 6.2% for fat‐in‐dry matter, 51.8% for moisture and 15.3% for water‐soluble nitrogen (as% of total nitrogen). Chemical composition of the cheese samples varied widely. Mouldy Civil cheese has similar pH values and moisture contents when compared with blue‐type cheeses, but it has distinct feature for fat contents. The microbiological counts of the samples were found to be high and some samples contained coliform bacteria. A total of 95 volatiles, including esters (28), acids (6), ketones (12), aldehydes (3), alcohols (15), terpenes (10), sulphur compounds (3) and miscellaneous (18), were identified in the volatile fractions of the cheeses, and principal volatile groups were esters, alcohols and ketones.  相似文献   

3.
Changes in the physico-chemical and microbiological properties of artisanal Turkish White cheese were studied throughout 105 days of ripening. Total solid, fat in solid, titratable acidity, pH, salt in total solid, total nitrogen, water-soluble nitrogen, ripening index, amino acids and biogenic amines were determined. Also, the counts of lactic acid bacteria, yeast, moulds and coliforms were done. Biogenic amines in cheeses were tyramine, histamine and phenyletylamine while tryptamine was the only detected at the beginning of maturation at the low concentration. Tyramine content increased during ripening reaching, 12.36 mg/kg at 75 days. A significant correlation could not be found (P>0.05) between microorganisms and biogenic amines. Data points represent averages of three experiments.  相似文献   

4.
Kaşar cheese samples were produced from raw milk and starter culture-added pasteurized milk. Chemical, microbiological and organoleptic properties of kaşar cheeses were analysed at certain times during the ripening periods (on the 1st, 7th, 15th, 30th, 60th, 90th days). Generally, chemical parameters were not affected by starter culture. The pH, ripening index, water-soluble nitrogen and non-protein nitrogen did not show significant differences between the cheese samples. The addition of starter affected the microbiological quality of the cheeses. Starter culture-added kaşar cheeses contained low levels of total aerobic mesophilic bacteria, moulds and yeasts, and coliforms, and achieved higher organoleptic scores than those of cheeses made from raw milk. The starter cultures contributed to acidity and microbial quality of the cheese.  相似文献   

5.
Physicochemical, microbiological and sensory characteristics, evolution of lipolysis monitored by measuring acid degree value (ADV) and the main mineral elements were studied during ripening and storage of artisanal Xinotyri cheese from raw goat's milk. Cheeses were characterized by a high content in total solids (TS; 83%) and fat (59% of TS), and very low pH (4.0), water activity (0.87) and moisture (17%). Protein and salt contents at the end of storage were 31% and 2.8%, respectively. Lipolysis increased, while variations in mineral (Ca, P, Mg and Zn) content were found during ripening and storage. Cheeses were free of Salmonella and Listeria in 25 g, while enterobacteria, pseudomonads, and coagulase-positive staphylococci were < 100 cfu/g. Mesophilic lactic acid bacteria increased above 8 log cfu/g by day 6, but declined by 2–3 logs in the ripened cheese (45 days) and by 3–4 logs during cheese storage at 4°C for up to 180 days.  相似文献   

6.
The aim was to investigate the physicochemical, microbiological and sensory properties of Pitina, a typical fermented meat product and evaluate the effect of two levels of pork lard content (Low Fat, LF, 10% vs. High Fat, HF, 30%) on its attributes. HF attained lower pH than LF Pitina, which reached lower water activity. LAB comprised the major flora with substantial counts of micrococci, enterococci and mould and yeast. Gram negative Enterobacteria were recovered as coliforms and faecal coliforms. Listeria monocytogenes was also isolated. The lard level influenced the count of micrococci and some sensory attributes. LF attained higher scores for both hardness and cohesiveness and differed from HF in having a more marked odour of ewe and smoke and sweeter taste. HF had a more pronounced odour and taste of garlic and mould than LF.  相似文献   

7.
Kavut is a cereal‐based product made from wholemeal wheat and barley flour, milk or milk powder, fat and sugar. In this study, the best processing method and formulation were investigated by analysing different formulations and processing methods for the kavut. Four different flour combinations (100% wheat without barley, 75% wheat + 25% barley, 50% wheat + 50% barley, 25% wheat + 75% barley), two shortening (butter and margarine) and three different roasting periods (1, 1.5, 2 min) at 250 °C were used in the study. Significant changes were observed in the physical and chemical properties of the cereal by heat treatment in the kavut production. Increase of barley flour in the mixture decreased protein content, softness, altered L colour values, appearance, texture, mouth‐feel, and general acceptance and increased ash content, +a and the absorbance value of kavut. While the longer roasting period resulted in reduced softness and colour (L‐value) of kavut, roasting period did not significantly affect the general acceptance of kavut. Kavut made from only whole wheatflour was most preferred by the panellists.  相似文献   

8.
In the present study, sufu, a soft cheese-like oriental fermented food, was prepared by ripening the salted-tofu cubes in Aspergillus oryzae-fermented soybean-rice koji at 37°C for 16 days (16-day sufu). Sufu was further held at room temperature for another 30 days (46-day sufu). The volatile components of the non-fermented tofu cubes and the sufu products were identified and quantified by GC and GC-MS. A total of 70 volatile compounds including 20 aldehydes, 18 alcohols, 16 esters, 5 ketones, 5 acids and 6 other compounds were identified. Sufu products contained more volatile compounds than non-fermented tofu cubes qualitatively and quantitatively. After 16-days of ripening, fatty acid, aldehyde and ester were noted to be the dominant volatile fractions. In contrast, the 46-day sufu contained ester, and alcohol as the major volatile fractions. They comprise approximately 63.9% of the total volatile components.  相似文献   

9.
Aho cheese, a traditional Turkish dairy product, is commonly produced in the eastern Black Sea region of Anatolia. In this study, 60 samples were collected and some biochemical, microbiological and sensory qualities were investigated. The mean values for dry matter, fat, protein, salt, ash and pH were 45.04, 8.10, 26.50, 9.58, 10.64 g/100 g and 5.07, respectively. Water‐soluble nitrogen (WSN), ripening index (WSN, % of TN) and acidity index were 0.59 g/100 g, 14.50% and 4.82 mg KOH/g fat, respectively. The mean values for saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids and polyunsaturated fatty acid/saturated fatty acid values were found to be 73.57, 23.08, 3.38 and 0.046 g/100 g fatty acids, respectively. Total aerobic mesophilic bacteria, yeast, mould and coliform counts were between 6.20–7.44, 4.84–6.96 and 0.00–2.45 log cfu/g, respectively.  相似文献   

10.
Coagulase-positive Staphylococci and microbial indicators of the 'Requeijão do Norte', a traditional semihard cheese, were surveyed in Brazil. Coagulase-positive Staphylococci were found in quantities of up to 9.4 log cfu/g. The coagulase gene was detected in isolates physiologically classified as coagulase-negative. The SEB and TSST-1 toxins were detected. Salmonella spp. were not detected. High levels of total and fecal coliforms (≥ 210 MPN/g) and moulds (≥   6.48 log cfu/g) were found in most samples. The values of physical–chemical parameters and water activity showed the greatest variations. These results suggest a possible risk that this cheese may pose to consumers.  相似文献   

11.
Kurut, which is made in villages of Eastern part of Turkey, is a sun‐dried dairy product. Thin‐layer drying behaviour of kurut at a temperature range of 35–60 °C, with 5 °C increments, and constant thickness of 0.5 cm and drying air velocity of 1.5 m s?1 was determined in a convective type dryer. The data of sample weight, dry and wet‐bulb temperatures were recorded continuously during each experiment and drying curves obtained. The drying process took place in the falling rate period. Drying curves were then fitted to eleven mathematical models available in the literature to estimate a suitable model for drying of kurut. Two‐term model gave better predictions than other models and satisfactorily described the thin‐layer characteristics of kurut. The effective diffusivity varied from 2.444 × 10?9 to 3.597 × 10?9 m2 s?1 over the temperature range. The temperature dependence of diffusivity coefficient was described by the Arrhenius‐type relationship. The activation energy for moisture diffusivity was found to be 19.88 kJ mol?1.  相似文献   

12.
A field experiment was carried out to investigate the effect of two Bradyrhizobium strains (local and imported), chicken manure fertilisation (7 t/ha) and intercropping with sorghum on the chemical composition and physical characteristics of soybean seed. For both monocropping and intercropping systems, moisture content slightly increased for both systems and for all treatments, while ash, fibre and carbohydrate contents fluctuated for both systems and treatments. The protein content of the seeds was significantly (p ? 0.05) increased for all treatments. Tannin content was increased significantly (p ? 0.05) with a concomitant decrease in protein digestibility for both systems and for all treatments. The seed weight (100 seeds), hydration coefficient and cookability were increased for all treatments. Mineral composition of the seeds was increased and the increment varied with different treatments.  相似文献   

13.
Gök V  Obuz E  Akkaya L 《Meat science》2008,80(2):335-344
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.  相似文献   

14.
In this study, some gross chemical compositions and fatty characteristics of herby cheeses were investigated. In the present study, the cheeses used as materials were collected from 10 different plants. The cheeses were made from sheep milk, cow's milk or a mixture of them, and stored in brine at 7–8°C and analysed for some proximate chemical compositions and fatty acid composition after 150 days of ripening. Capric acid, palmitic acid, oleic acid, short-chain fatty acids, medium-chain fatty acids, long-chain fatty acids, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids and other fatty acids as g in 100 g fatty acids were determined.  相似文献   

15.
The microbiological and physicochemical characteristics of several commercial beef, kudu and springbok biltong samples from South Africa were assessed in this study. Analysis of samples allowed their differentiation into ‘dry’ and ‘moist’ samples. Dry biltong showed low moisture content (21.5–25.3 g/100 g), a low water activity (0.65–0.68) and a high salt content (5.5–7.9 g/100 g), while moist biltong showed a higher moisture content (35.1–42.8 g/100 g), a higher water activity (0.85 to 0.89) and a lower salt content (3.8–5.6 g/100 g). The pH value did not vary significantly between both groups (5.00–6.26). The results showed that dry biltong presented a low total plate count (TPC) content, a high level of lactic acid bacteria (LAB) and a high level of d-lactic acid as compared to moist biltong. These results suggest that dry biltong complies with the standard hygienic quality (TPC < 7 log cfu/g in agreement with the Food Standards Agency), while moist biltong samples generally showed a low content of d-lactic acid and a low ratio LAB/TPC.  相似文献   

16.
This study was designed to investigate the microbiological and chemical characteristics of kurut, a dairy product obtained by drying yogurt under the sun in rural areas of Turkey. For this purpose, 50 randomly collected kurut samples from the Kars Region were analysed for determination of their microbiological and chemical characteristics. Analysis of kurut samples showed that kurut contained on average 4.52 log10 cfu/g of aerobic mesophilic bacteria, 2.78 log10 cfu/g of aerobic mesophyl spores, 3.60 log10 cfu/g of lactic acid bacteria, 3.60 log10 cfu/g of Lactococcus , 3.94 log10 cfu/g of mould and yeast, 2.13 log10 cfu/g of Enterobacteriaceae, l.51 log10 cfu/g of sulphite-reducing clostridia, and 1.81 log10 cfu/g of coagulase-positive s taphylococci . Coliform bacteria and enterococci bacteria were not detected in any of the kurut samples. Furthermore, chemical characteristics of the kurut were as follows: pH 4.2, acidity (lactic acid) 2.9, moisture 12.1%, fat 45.9% protein 25.5%, salt 6.7% and ash 10.0%. The quality characteristics of kurut presented here may help create a different perspective for new products to be produced in the dairy sector.  相似文献   

17.
以50个普洱熟茶为研究对象,采用主成分分析和偏最小二乘回归分析法,研究11个化学成分和感官审评结果间的相关性,揭示影响品质特性的主要因子。结果表明,水浸出物、总糖、茶多糖、茶多酚、氨基酸和茶色素与品质呈正相关;水分、总灰分、pH值、粗纤维和咖啡碱与品质呈负相关。  相似文献   

18.
中国烟叶矿质营养及主要化学成分含量特征研究   总被引:63,自引:4,他引:63  
利用2002年抽样调查的220个烤烟样品,对我国烤烟中的氮、钾、磷、钙、镁、锰、铜、锌、硼、钠、铁、氯、烟碱、还原糖等14个指标的含量特征进行了分析。结果表明:1)除钙、钠、锌、硼、还原糖、烟碱外,其余指标在品种之间的差异极显著,但不同指标在品种之间的高低秩序不同。在样本数较多的K326、云烟85、云烟87、NC82、NC89中,K326的钾含量为1.79%,显著地高于云烟85、NC82、NC89,NC82、云烟87的氯含量分别为0.39%、0.32%,显著地高于K326、云烟85、NC89中的氯含量;2)氮、硼、烟碱含量从上部烟叶到下部烟叶显著地依次降低,而钾、铁、还原糖则从上部烟叶到下部烟叶显著地依次升高;3)烟碱含量地域之间的差异不明显,而其余指标在地域之间的差异极显著,但不同指标在品种之间的高低秩序不同。河南烟叶的钾含量显著地低于其他省份,贵州烟叶的氯离子含量显著地高于其他地方,湖南烟叶的还原糖含量显著地低于其他所有地方;4)我国烟叶氮、磷、钾、钙、镁、锰、氯、铜、锌、硼、钠、铁、烟碱、还原糖含量落在巴西烟叶范围之内的理论概率分别为0.525、0.598、0.485、0.338、0.462、0.839、0.449、0.384、0.275、0.586、0.621、0.586、0.739、0.684;还原糖、烟碱、钾、氯含量符合"国际型优质烟叶"质量标准的概   相似文献   

19.
This study aimed to assess the nutritional, hygienic and sensory characteristics of donkey milk produced in Greece and Cyprus. The average values for pH, fat, protein and lactose were 7.14, 0.52 g/100 mL, 1.22 g/100 mL and 7.01 g/100 mL, respectively, whereas aflatoxin M1 and beta‐lactam residues were not detected in any sample. The microbiological analysis revealed very low somatic cell counts and total microbial counts, while Escherichia coli, Salmonella spp and Listeria monocytogenes were not detected in any sample. The sensory evaluation classified the milk as white, thin, with a slightly sweet pleasant taste, pleasant milky aroma, sweet flavour and no persistent aftertaste.  相似文献   

20.
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