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1.
The current trial determined the influence of dietary humate, including humic, fulvic and ulmic acids and some microminerals on the pH, TBARS and microbiological properties of vacuum‐packed and aerobic‐packed breast fillets and drumsticks of broilers. A total of 240 male broiler chicks (Ross‐308) were randomly allocated into four dietary treatments (H0, H1, H2 and H3 groups). A basal diet (H0), basal diet plus 0.1 (H1), 0.2 (H2) and 0.3% (H3) humate (Farmagulator DRY?, Humate, Farmavet International Inc, Kocaeli 41 400, Turkey) were offered during the experimental feeding period. At the end of the trial all chicks were slaughtered. After standard dissection of carcasses, the breasts and drumsticks were divided into two groups for vacuum packaging or aerobic packaging. Packed breasts and drumsticks were stored at 3 °C for 12 days. The breasts and drumsticks were analyzed for pH, TBARS, total mesophilic, total psychrotrophic, lactic acid bacteria and Enterobacteriacea counts at 0, 2, 4, 6, 8, 10 and 12 days of storage. The feeding of humate decreased pH values of breast fillets and drumstick muscles (p < 0.01), especially at the 0.1% level. The TBARS value decreased (p < 0.01) when compared with the without‐humate group (H0). Total aerobic mesophilic (p < 0.01), total aerobic psychrotrophic (p < 0.01) and lactic acid bacteria (p < 0.05) counts were lower in the H3 group than the other groups. The effect of meat type on pH, TBARS, total aerobic mesophilic (p < 0.01) and lactic acid bacteria (p < 0.05) and Enterobacteriacea counts was significant. While the pH and TBARS values of breast fillets were lower than those of drumstick meats, the total mesophilic, total psychrotrophic, lactic acid bacteria and Enterobacteriacea counts of drumstick meats were higher than those of breast fillets. The effect of packaging type on pH (p < 0.01), TBARS (p < 0.01), total aerobic psychrotrophic bacteria (p < 0.01) and Enterobacteriacea counts (p < 0.01) was found statistically significant and the maximum values were determined in the aerobic‐packed samples. In addition, investigated parameters were also affected by storage period. While the total aerobic mesophilic count decreased, the other parameters increased when compared with zero day of storage. Copyright © 2005 Society of Chemical Industry  相似文献   

2.
The effects of green tea,grape seed polyphenols and ascorbic acid on pH, water activity (aw), microbiological counts, TBARS, residual nitrite and N‐nitrosamines were determined in dry‐cured sausages during the ripening period. Results showed that TBARS increased gradually during ripening (< 0.05), but were significantly reduced with plant polyphenols and ascorbic acid (< 0.05). Green tea polyphenol (GTP) was most effective (< 0.05) in reducing TBARS. Plant polyphenols and ascorbic acid significantly decreased residual nitrite, ascorbic acid being most effective (< 0.05). The amount of N‐nitrosamines increased during ripening, but was significantly reduced with plant polyphenols and ascorbic acid (< 0.05). Plant polyphenols had no significant effects on moisture content, aw, pH or microbiological counts in dry‐cured sausage during ripening (> 0.05). It was concluded that plant polyphenols and ascorbic acid were effective in maintaining the quality and safety of dry‐cured sausages.  相似文献   

3.
The effects of the use of antioxidant technology on the quality of mackerel burgers stored at 4 °C were investigated in terms of sensory, biochemical [thiobarbituric acid (TBA), total volatile basic nitrogen (TVB‐N), peroxide value (PV) and free fatty acids (FFA)] and microbiological analyses [total viable count (TVC)]. Fish meat was divided into three groups; the control (C) without rosemary extract, the second group with 0.4% rosemary extracts (Group A) and the third with 0.8% rosemary extracts (Group B). Results showed that the TVB‐N level did not exceed acceptability limit (30–35 mg 100 g?1) for all groups. TBA value for the control significantly increased from 1.47 to 4.80 MA kg?1 whereas it slightly increased in treatment groups as the storage time increased. Significantly higher PV and FFA (P < 0.05) were obtained from the control group. Rosemary extract, in combination with vacuum pack was effective in controlling the growth of bacteria and biochemical indices.  相似文献   

4.
The effect of inoculum level of Bifidobacterium animalis ssp. lactis BB‐12 probiotic strain and ripening period on the quality of dry‐cured neck was studied. The microbiological parameters (Enterobacteriaceae, LAB and TVC) and physicochemical attributes (pH value, aw, TBARS index, colour) were determined directly after fermentation at 15 °C for 3 weeks, after 6 and 12 months of ripening at 4 °C. The highest LAB count and a lower pH value were found in the meat inoculated with probiotic strain at 6.6 log cfu g?1 (B2) followed by inoculation with probiotic strain at 6.3 log cfu g?1 (B1). Level of inoculation had not had an influence on water activity, TBARS index and total colour parameters. Changes of fat oxidation during half‐year of ripening were limited in probiotic meat samples compared to naturally fermented control meat (C). Based on the results, it can be concluded that the most favourable physicochemical and microbiological parameters of the dry‐cured neck were obtained after 6 months of ripening. At that time, the Bifidobacterium BB‐12 at both levels is a good potential starter for meat fermentation.  相似文献   

5.
The preservative effects of Zataria multiflora Boiss essential oil (ZEO) at 0.025%, 0.05% and 0.1%, sodium acetate (SA) at 2% and their combination on the quality changes of vacuum‐packaged trout burgers during 21‐day refrigerated storage (4 ± 1°C) were investigated. Results showed that control and ZEO‐treated samples reached undesirable levels of rancidity (< 0.05) at 15th day, whereas samples with the combined effect of SA and ZEOs, especially at higher concentrations, proved to be more stable in sensory, biochemical (PV, TBA, FFA and pH) and microbiological analyses (< 0.05). Therefore, ZEO+SA‐treated samples showed good overall acceptability even until 21st day. Regarding the results obtained from ZEO‐treated samples, it becomes apparent that combined application of SA and ZEO extended the shelf life of fish burgers during cold storage to 21 days, 1.4‐fold longer than other treatments, which indicates the potential application of synergistic activity of these agents in vacuum‐packaged fishburgers.  相似文献   

6.
The antioxidant activities of ethanol extracts of rosemary (Rosmarinus officinalis L.) (RE) were tested in natural sunflower oil stored at 60 °C by measuring their peroxide values (POV), thiobarbituric acid‐reactive substances (TBARS), free fatty acid (FFA) content and p‐anisidine value (AnV) after regular intervals compared with synthetic antioxidants. After 3 weeks of storage at 60 °C, sunflower oil containing 200 mg kg?1 rosemary extracts showed lower POVs (75.7 ± 0.47  meq kg?1), thiobarbituric acid‐reactive substances (TBARS)(0.161 ± 0.002 μg mL?1), FFA contents (0.45 ± 0.04 mg g?1) and AnV (12.4 ± 0.02) than the control sample. Sunflower oil containing 200 ppm butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert‐butylhydroquinone (TBHQ) showed POVs (204 ± 0.68, 159 ± 0.55, 20 ± 0.49 meq kg?1), thiobarbituric acid‐reactive substances (TBARS) (0.171 ± 0.002, 0.184 ± 0.002, 0.069 ± 0.001 μg mL?1), FFA contents (0.34 ± 0.03, 0.46 ± 0.03, 0.2 ± 0.01 mg g?1) and AnV (14.7 ± 0.03, 16.5 ± 0.04, 6.77 ± 0.01), respectively, after 3 weeks of storage at 60 °C. These results illustrate that rosemary extracts exhibited very strong antioxidant activity, almost equal to that of synthetic antioxidants (BHA and BHT).  相似文献   

7.
In this study, fermentation of Allium chinense bulbs was carried out with Lactobacillus plantarum ZDY 2013. A decrease in pH from 6.8 to 3.5 and a stable lactic acid bacteria population were observed during 7‐d fermentation. The total phenolic content increased by 2.7‐fold in the aqueous and ethanol extracts of A. chinense bulbs after fermentation. Antioxidant capacity including 2,2‐diphenyl‐1‐picrylhydrazyl radical‐scavenging effect and reducing power of both extracts was significantly (< 0.05) improved after fermentation. Antagonistic test against 6 pathogens showed that fermentation significantly (< 0.05) enhanced the antimicrobial activity in both extracts of fermented bulbs, especially in the ethanol extracts of fermented bulbs against L. monocytogenes. Analysis of the free amino acid (FAA) profile by ion‐exchange chromatography revealed that fermentation significantly (< 0.05) increased total FAA content. In addition, among 27 kinds of volatile components analyzed by headspace–solid phase microextraction–gas chromatography–tandem mass spectrometry, sulfur‐containing compounds accounted for 65.23%, but decreased to 43.65% after fermentation. Our results suggested that fermentation of A. chinense bulbs with L. plantarum could improve their biofunctionalities, and nutritional and chemical properties.  相似文献   

8.
Physical (colour), chemical (pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid values (TBA)) and microbiological (total aerobic mesophylic bacteria, salmonella, coliform, yeast and mould counts) analyses were carried out on thawed European eel (Anguilla anguilla). Different thawing treatments were used (in a refrigerator, in water, in air at ambient temperature and in a microwave oven). The results obtained were compared statistically with those of fresh fish. pH, TBA and a values of thawed samples usually decreased significantly (P < 0.05) when compared to the fresh control. Salmonella was not detected in any of the samples. Coliform and mould counts of fresh control and thawed samples were <1 CFU/g. Total aerobic mesophylic bacteria count of all thawed fish decreased. However, the yeast count of the refrigerator–thawed samples increased. The lowest total aerobic mesophylic bacteria and yeast counts were determined in water–thawed samples. Water thawing is therefore suitable for frozen eel.  相似文献   

9.
The quality assessment of the wild European eel (Anguilla anguilla) stored at −20 °C was assessed by sensory, chemical (total volatile basic nitrogen (TVB-N), peroxide value (PV), free fatty acid (FFA), thiobarbituric values (TBA) and pH) methods. The sensory analysis of showed that European eels were acceptable by panellists and can be stored for more than 48 weeks at −20 °C. No effects of frozen storage were observed on the proximate composition of eel. The level of TVB-N showed fluctuations (7.09–14.72 mg TVB-N/100 g) during frozen storage period, thus TVB-N could not be used as an indicator of frozen eel quality. FFA, PV and TBA values showed fluctuations during frozen storage period but remained low at the end of storage period, PV reached to the maximum level of 13.20±1.73 meq/kg, which did not exceed the maximum recommended value for human consumption (20 meq/kg). The release of FFA slightly increased (P>0.05) from the initial value of 0.88 to 2.14 (expressed as % of oleic acid) until 32 weeks of frozen storage while TBA increased from the initial value of 0.085 mg MA/kg to maximum level of 0.7696 mg MA/kg after week 40. After that, their values decreased to 1.82 and 0.5577 at week 48, respectively. This study showed that off-flavour and off-odour was not detected and frozen European eels were still acceptable by panellists and can be stored for more than 48 weeks at −20 °C.  相似文献   

10.
The present study deals with the effect of acid whey (AW) on physicochemical properties of non‐nitrite organic dry‐cured pork loins. The loins were divided into three experimental batches: with the curing mixture (C), with sea salt (S) and with sea salt combined with AW (SW). The evolution of physicochemical properties, colour, fatty acid profile and microbiological quality were assessed at 0, 30 and 90 days of refrigerated storage. Physicochemical parameters of dry‐cured organic loins were significantly (P < 0.01) affected by treatment, storage time and the interaction between them. Sea salt in combination with AW was the most successful at reducing the browning reaction involved in the formation of dark colour in dry‐cured loins. Significant reduction in a* value (P < 0.05) caused by replacement of curing salt by sea salt has been less pronounced in sample with AW. Storage diminished (P < 0.01) initial differences in profile of SFA, MUFA and n‐3 induced by treatment method. AW added to uncured loins was able to protect PUFA against oxidation comparable to nitrite. The highest count of lactic acid bacteria (LAB) in dry‐cured loins with AW was accompanied by their lower pH (P < 0.05).  相似文献   

11.
Lobster krill (Munida genus) represents an under‐valued crustacean frequently caught on European fishing banks. In this work, its sensory, microbiological and biochemical qualities were evaluated during chilled storage. Additionally, the effects of a prestorage antimelanosic treatment consisting of soaking in sodium metabisulphite (SMB) solutions at two different concentrations (0.25% and 0.75%) were also studied. SMB prestorage treatment provided lobster specimens that still exhibited acceptable sensory quality after 10 days of storage, while control specimens were unacceptable at that time. SMB treatment also resulted in a significant (P < 0.05) inhibition of microbial growth, mainly of Enterobacteriaceae, psychrotrophes and proteolytic bacteria. Low lipid oxidation levels were observed for all batches; however, a significantly higher (P < 0.05) retention of polyunsaturated fatty acids was found in SMB‐treated lobster, especially in the 0.75% SMB batch. The results presented here open the way to the potential commercialisation of currently under‐utilised lobster krill as a chilled product.  相似文献   

12.
The effects of the use of natural antioxidants on the quality of frozen chub mackerel (Scomber japonicus) burgers stored at ?18 °C were investigated in terms of sensory, biochemical (thiobarbituric acid reactive substances-TBARS, total volatile basic nitrogen, peroxide value and free fatty acids) and microbiological analyses (total viable count—TVC, total psychrotrophic count—TPC). Oregano, green tea, sage and laurel extracts were obtained by using steam distillation method. After that, thawed fish were headed, gutted and filleted. Fillets were then minced and divided into nine groups. These were the control without plant extract, O1 with 0.3% oregano extract, O2 with 0.6% oregano extract, G1 with 0.3% green tea extract, G2 with 0.6% green tea extract, S1 with 0.3% sage extract, S2 with 0.6% sage extract, L1 with 0.3% laurel extract and L2 with 0.6% laurel extract. Plant extracts together with burger ingredients were added to each group. All groups were stored at ?18 °C for 9 months. According to the results of sensory analyses, the control at 7 months of storage, oregano and green tea at 9 months of storage, sage and laurel groups at 8 months of storage were rejected by panellists and considered as unaccepptable. Natural extracts were effective in controlling biochemical indices. TVC content of fish burgers did not exceed the limit during storage period for all groups (<6 log CFU/g). TPC slightly decreased with storage time. Additions of oregano, green tea and laurel extracts except sage extract reduced (P?<?0.05) lipid oxidation in fish burger and have the potential to be incorporated into fish burgers.  相似文献   

13.
The aim of this study was to investigate the lipolysis and lipid oxidation of Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31 in Suan yu. Suan yu were made inoculated with and without two strains at different stages, and model systems of emulsions were also established. Lipolysis and lipid oxidation were evaluated by determining the changes in free fatty acid (FFA) content and composition, conjugated diene (CD) value and thiobarbituric acid reactive substances (TBARS) value. The total FFA of the sample without cultures increased from 476.61 mg/100 g fat to 1413.89 mg/100 g fat after 5 weeks fermentation, while those of samples with cultures declined to 258.98 and 452.89 mg/100 g fat, respectively. On the other hand, CD and TBARS values of samples with inoculation markedly increased. In the model system, higher FFA, CD and TBARS values for the samples added with CFE were observed. This study showed that Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31 made a significant contribution to lipolysis and lipid oxidation during the processing of Suan yu.  相似文献   

14.
Polysaccharide extracts (0.05 ~ 0.15% w/w) from Lactarius volemus Fr. were used as growth factors and were incorporated into three different probiotic yoghurts. Yoghurts with polysaccharide extracts had a significantly improved water‐retention capacity and reduced pH (P < 0.05). Polysaccharide extracts also significantly increased the viable count and essential amino acid content in the probiotic yoghurts (P < 0.05). The best sensory properties were achieved with the addition of 0.10% polysaccharide extracts. Our study suggests that polysaccharide extracts from L. volemus Fr. are a highly efficient growth factor for shortening the fermentation period and improving the quality of probiotic yoghurts.  相似文献   

15.
Antioxidant activities of Myrtus communis leaf phenolic compounds (McPCs) were investigated on 2,2′‐9‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS+?) and oxygen radical absorbance capacity (ORAC) tests or on oxidation of biological models, human low‐density lipoprotein (LDL) and phospholipid aqueous dispersion (l ‐α‐phosphatidylcholine stabilized by bile salts). Two extraction techniques, microwave‐assisted (MAE) and conventional (CE), were used to isolate McPCs, producing similar results of phenolic compound content. ABTS+? assay showed clearly that myrtle extracts exhibited a stronger scavenging effect than butylated hydroxyanisole and α‐tocopherol, with a slight advantage for myrtle CE extract. In ORAC assay, the both McPC extracts were similarly less effective than the pure compounds as caffeic acid and myricitrin (myricetin 3‐O‐rhamnoside) but stronger than butylated hydroxytoluene. Moreover, myrtle CE and MAE extracts, and myricitrin were able to inhibit similarly the production of conjugated dienes and to prolong the lag phase (Tlag) during Cu2+‐induced LDL oxidation with a dose‐response effect. The cryo‐electron microscopy observations on studied phospholipid dispersion stabilized by bile salts (BS) revealed the presence of bilayer vesicles and micelles. In 2,2′‐azobis (2‐amidinopropane) hydrochloride–induced phospholipid/BS oxidation, myrtle CE and MAE extracts gave similar effects to α‐tocopherol and caffeic acid but myricitrin showed a higher protective effect than myrtle extracts. We showed also that no synergic or additive effect between α‐tocopherol and myrtle extracts or caffeic acid in α‐tocopherol–enriched phospholipid/BS dispersion, but myricitrin showed an additive effect and thus promoted the total antioxidant activity. These data showed that myrtle extract could be used as potential natural antioxidants, food stabilizers, or natural health products.  相似文献   

16.
The effects of modified atmosphere on some physical, chemical and microbiological properties of sliced past?rma made from beef Longissimus dorsi muscle were investigated. Sliced‐past?rma samples (moisture 43.65 ± 0.15%, pH 5.71 ± 0.02) were stored in modified atmosphere packages (50% N2 + 50% CO2) at 4 and 10 °C for 150 days. The storage period had a significant effect (p < 0.01) on moisture, pH, thiobarbituric acid reactive substances, free fatty acid, non‐protein nitrogen, water‐soluble nitrogen, colour values and total aerobic bacteria, lactic acid bacteria and Micrococcus/Staphylococcus counts. The storage temperatures (4 and 10 °C) also had a significant effect (p < 0.01) on moisture, pH, thiobarbituric acid reactive subctances, free fatty acid, water soluble nitrogen, a* values, total aerobic bacteria lactic acid bacteria, and Micrococcus/Staphylococcus counts. It was determined that the storage period × the storage temperature interactions had a significant (p < 0.01) effect on the values of pH, a* and the counts of total aerobic bacteria, lactic acid bacteria, Micrococcus/Staphylococcus. It was also observed that the yeast and mold count was the highest in the first storage period and decreased throughout storage. Enterobacteriaceae count was also below the detectable level (<2.00 cfu g?1) throughout the storage period. Copyright © 2005 Society of Chemical Industry  相似文献   

17.
This study invest0igated the effect of CO2 added to achieve three pH levels: pH 6.1, pH 6.2 and pH 6.3 for treatments X, Y, Z, respectively, on some microbiological properties of Turkish White (TW) brined cheese. For each pH, four batches of cheese were produced from: raw milk with no added carbon dioxide (UR), raw milk with carbon dioxide (TR), pasteurised milk with no carbon dioxide addition (UP) and pasteurised milk with carbon dioxide addition (TP). The microbiological analysis of TW brined cheeses was carried out for 90 days of maturation period. Total aerobic mesophilic bacteria, mesophilic lactic acid bacteria, yeasts and moulds and coliform group were determined in control and CO2 treatment groups. Mesophilic bacteria count was determined as 5.14, 5.29, 5.67 log cfu/g for pH 6.1, 6.2 and 6.3, respectively, in CO2‐treated raw milk cheeses. Yeasts and moulds reduction increased significantly by applying CO2 (P < 0.01). For TW cheese samples, the most significant microbial inactivation was detected at sample groups of pH 6.1.  相似文献   

18.
The study focuses on the impact of icing systems with aqueous (AQ batch), ethanolic (ET batch) and ethanolic‐aqueous (ET‐AQ batch) extracts of alga Fucus spiralis on the microbial and biochemical quality of chilled hake (Merluccius merluccius). After a 13‐day storage, comparison with fish kept under traditional ice proved a significant (P < 0.05) antimicrobial effect against aerobes, psychrotrophs, proteolytic and lipolytic bacteria, derived of the presence of F. spiralis ethanolic extracts in the icing medium (ET and ET‐AQ batches). Additionally, an inhibitory effect of both ethanol extracts was also obtained concerning lipid oxidation development (i.e. secondary and tertiary lipid oxidation compounds). Additionally, lipid damage assessment showed lower mean values in tertiary oxidation compound formation in hake belonging to the ET‐AQ batch throughout the whole storage period. Present research indicates that ET‐AQ ice condition can lead to a marked quality and safety enhancement as well as to profitable commercial value increases.  相似文献   

19.
ABSTRACT Vacuum‐packaged ground ostrich meat patties containing 2% sodium lactate (SL), 0.2% rosemary extract as oleoresin (RE), or their mixture (MIX) were evaluated and compared with control for their storage stability at 3 ± 1 °C in the dark by measuring pH, 2‐thiobarbituric acid‐reactive substance (TBARS) values, sample color (CIE L*, a*, b*, Hue and Chroma), and microbiological content. The pH values of ostrich patties, ranging from 6.03 to 6.13, were not affected by treatment (P < 0.05). At 9 d of storage, TBARS concentration for control samples containing no additives was 1.64 mg malonaldehyde/kg meat. Addition of RE to the ground ostrich meat inhibited lipid oxidation during storage at 3 ± 1 °C (P < 0.05). TBARS values of SL‐added samples were lower than control samples (P < 0.05); addition of SL also delayed the oxidation. It was found that RE had a protective effect on color, whereas addition of SL decreased CIE a* values (P < 0.05). SL, either alone or with RE, was effective in inhibiting total aerobic bacteria (TAB), coliforms, lactic acid bacteria (LAB), and Brochothrix thermosphacta in ostrich patties (P < 0.05) and provided a 2‐log reduction in microbial population during storage. In addition, RE did not have a significant effect on microbial growth at the concentration used in this study.  相似文献   

20.
The aim of this study was to evaluate the effects of the application of beeswax coating on the microbiological, physicochemical and sensory properties of Kashar cheese during ripening (120 day). Kashar cheeses were coated with two different thickness of beeswax (single‐layer coating, BW1, and double‐layer coating, BW2). For comparison, vacuum packaged (VP) and without packaging material (control) were also studied. Generally, no differences were found in total aerobic mesophilic bacteria, LAB on M‐17 agar, coliform bacteria and S. aureus counts among cheeses. Microbiological analyses also showed the beeswax‐coated cheeses presented a decrease of 2.5 logarithmic units on mould counts compared to control at 120th day. The control cheese had significantly (P < 0.05) higher dry matter, fat and protein contents, followed by BW1. However, the coating reduced formation of a thick crust layer by delaying moisture loss. At the end of 120‐day storage period, no significant differences in pH and acidity values were observed among the cheeses studied. Compared to other cheeses, control and BW1 cheeses had higher levels of WSN and ripening index in the end of storage. In the result of sensory analysis, while cheese BW1 and control were more preferred by the panellists, cheese VP received the lowest scores.  相似文献   

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