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1.
Snow crab (Chionoecetes opilio) presents a commercial and economical important product with attractive sensory attributes. Today, snow crab is captured in the North Pacific, Arctic and Northwest Atlantic and it is mainly exported to the US, Canada, Japan, South-Korea and Europe as live, cooked and refrigerated or frozen. The aim of this work was to estimate shelf life of leg meat in cooked and raw snow crab clusters (one claw plus 4 legs) using sensory, microbial and chemical analysis when stored at 4 and 0 °C. The results revealed a shelf life of 10 and 14 days for cooked clusters stored at 4 and 0 °C, respectively. Corresponding maximum levels of TVC and pseudomonads at 4 °C were log 5.5 and 3.2 CFU/g, respectively, while complementary levels at 0 °C were log 4.9 and 4.2 CFU/g. Shelf life of raw clusters stored at 0 °C was 6 days. This shelf life corresponds to maximum levels of TVC and pseudomonads of approximately log 2.5 CFU/g showing that pseudomonads is the dominant microflora. For cooked clusters, sensory and microbial analyses were the best shelf life indicators, while sensory analysis was the best shelf life indicator in case of raw clusters.  相似文献   

2.
    
The shelf life of rabbit meat during refrigerated storage was investigated under industrial conditions. Rabbit carcasses were bulk packed (BP), packed under air (PUA) and under modified atmosphere (MAP) (30% O2:40% CO2:30% N2). The main groups studied were mesophilic aerobes, psychrotrophic aerobes, Pseudomonas spp., lactic acid bacteria, yeast and moulds and Enterobacteriaceae. The microorganisms that showed faster growth were psychrotrophic aerobes (growth rate of 0.36 ± 0.09 day−1) for BP, Pseudomonas (0.26 ± 0.03 day−1) for PUA, and lactic acid bacteria (0.22 ± 0.01 day−1) for MAP, and the lag phases were 4, 4 and 8 days, respectively. The main effect of MAP was the increase in lag phase from 4 to 8 days, for lactic acid bacteria, psychrotrophic and mesophilic aerobes. The respective growth rates were similar to those observed with PUA. In addition, MAP inhibited Pseudomonas growth during 18 days. Considering 6 log CFU g−1 as maximum tolerable microbial load, the calculated values of shelf life in BP, PUA and MAP were 6, 7 and 12 days, respectively, when considering the fastest growing microorganisms.  相似文献   

3.
    
The combined effect of Citrus wilsonii extract and alginate-calcium film coating on microbiological, chemical and sensory changes of white shrimps (Litopenaeus vannamei) was studied over 6 days of storage at 4 °C. A specific spoilage microorganism Lysinibacillus sphaericus S1 was isolated from local shrimp samples, which could cause the appearance of orange spoilage spots. The methanol extract of C. wilsonii exhibited significant antimicrobial activity against L. sphaericus S1, as well as several other food-borne pathogens. GC–MS analysis showed a high percent of furandione and furfural compounds in the extract. The extract with edible alginate-calcium coating was effective in delaying the quality deterioration of the shrimps stored at 4 °C. Total viable count of the treated shrimps was more than 10 times lower than the negative untreated control. The lower rate of the increase in pH and total volatile base nitrogen (TVB-N) was also observed in shrimps treated with the extract compared to the control group shrimps. After 6 days of refrigerated storage, shrimps treated with the extract combined with coating had the significant higher sensory score for odor, color and texture. The results suggest that the methanol extract from C. wilsonii may be promising to be developed as a new eco-friendly preservative that might be applied to extend the shelf life of shrimps maintaining good quality.  相似文献   

4.
    
Red king crab (Paralithodes camtschaticus) presents a commercial and economical important species that is mainly consumed in high-end markets in Japan and USA. The product is either sold live, cooked and refrigerated or frozen. The meat in the legs and in the shoulder is utilized. In this study, shelf life of cooked king crab clusters (shoulder plus three legs) during chilled storage was studied. We utilized sensory, chemical and microbiological methods to describe spoilage during storage of the clusters, and to estimate its shelf life. The results revealed that a cluster is a heterogeneous product, where the shelf life of the leg and shoulder meat is 8 and 5 days, respectively, during chilled storage. As it is impractical to operate with two different shelf lives for the same product, the overall recommended shelf life is 5 days for cooked and chilled clusters. Corresponding maximum level of TVC and Pseudomonas spp. in leg meat stored for 5 days was log 4.6 and 3.7 CFU/g, respectively. A correlation between odour of the shoulder joint and flavour of the leg meat was revealed. By using, exponential regression, the flavour of the leg meat could be predicted based on the odour of the shoulder joint.  相似文献   

5.
    
The coating effects of chitosan and chitosan nanoparticles on the quality of silver carp (Hypophthalmicthys molitrix) fillets during refrigerated storage at 4 °C were compared. Solutions of Chitosan (2%, w/v) and nanochitosan (2%, w/v) were used for the coating. The control and the coated fish samples were analyzed periodically for microbiological (total mesophilic and psychrotrophic count), physicochemical (pH, TVB-N, TBARS), and sensory attributes. The results indicated that both chitosan and nanochitosan coating were effective for the preservation of silver carp fillets during refrigerated storage. However, nanochitosan exhibited higher antimicrobial activity than chitosan during the storage period. Furthermore, nanochitosan showed a stronger ability to inhibit the TVB-N content than chitosan. Therefore, to extend the shelf life and delay the deterioration of fresh silver carp fillets during refrigerated storage, nanochitosan coating is more effective.  相似文献   

6.
    
An active shrimp concentrate (SC), obtained from Litopenaeus vannamei cooking juice, was incorporated into a chitosan-gelatin matrix to develop edible packaging covers (coating and film). Both types of packaging, which showed antimicrobial activity against some fish spoilers and pathogenic organisms, were applied to preserve fish sausages during chilled storage. The storage trial showed that the coating increased the lag phase of total viable microorganisms and enterobacteria to 15 and 10 days, respectively, while the film drastically inhibited growth of these groups. No presence of Staphylococcus aureus or lactic acid bacteria was detected in any batches during storage. Total volatile bases and pH values also decreased during storage, the decrease being more pronounced in the film. With regard to physical-chemical properties, the coated sausages exhibited values for moisture, water holding capacity, and shear strength similar to those of the control sausages until about day 25. The coating was imperceptible and could be a promising way of improving the quality of sausages during storage since it delayed microbial growth. The sausages wrapped in the film showed a drop in pH and moisture, as well as texture hardening, and were described as resembling a pickled product. The sausages were stable for at least 42 days, which represents a shelf life increase of at least this time with respect to the control sausages (in commercial plastic casings). The coating and the film had different effects on the physicochemical and microbiological properties of the fish sausage, and therefore on the stability of the product. In addition, the film triggered modifications in the product that resulted in a product different from the original, offering an attractive alternative with regard to product design.  相似文献   

7.
    
Based on an on-line survey using questionnaires, information on Belgian consumers (n = 907) regarding their understanding and attitude towards shelf life labels and dates was collected. 80.1% of the respondents were familiar with the terminology of the label use by and best before while 69.6% indicated to know the difference between the meaning of the two labels. Judging edibility of food products at home occurs mainly by a combination of checking visually and smelling (82.5%), followed by looking at the shelf life date (67.5%) or tasting (50.4%). About half of the consumers is aware of and appreciates the difference between the two labels during this judgment. Most of the consumers interpret shelf life labels and dates with some flexibility, with variation depending upon the type of food product under consideration. Overall, the share of consumers willing to eat expired refrigerated products was lower than for expired products stored at ambient temperature: 19.1% for refrigerated raw products (e.g. meat and fish); 34.7% for refrigerated ready-to-eat products (e.g. deli-meat, cheese products, smoked fish); 61.0% for canned products (e.g. conserves) and drinks (e.g. beer) and lastly 69.3% for other products generally stored at ambient temperature (e.g. bread, unopened UHT milk, chocolate, cereals). Differences linked to age and gender are discussed. The suboptimal understanding and application of the EU date label framework by consumers may lead on the one hand to increased food disease burden by consuming certain expired use by products allowing growth of pathogens. On the other hand discarding food at the shelf life data in case of a best before date contributes to food waste by consumers. A better understanding of the shelf life labels use by (referring to food safety) and best before dates (referring to food quality) by consumers should be promoted.  相似文献   

8.
    
This study investigated the screening of antifungal potential of Lactobacillus helveticus. L. helveticus KLDS 1.8701 showed strongest antifungal activity against Penicillium sp. of all provided strains, and antifungal activity was from organic acids and KLDS 1.8701 itself. Results of the impact of KLDS1.8701 on spoilage microorganisms in fermented soybean milk during the preservation period showed that it could inhibit Penicillium sp. and other spoilage microorganisms from the environment and the shelf-life of products were extended. The addition of KLDS 1.8701 has no significant effect on biochemical, rheological and sensory properties of fermented soybean milk. It also enhances total viable counts of Lactobacillus stains (L. helveticus + Lactobacillus bulgaricus)and didn't affect Streptococcus thermophiles. Thus, the use of L. helveticus KLDS 1.8701 as a bio-protective culture in other fermented products was suggested.  相似文献   

9.
    
The effects of rosemary extract (RE) combined with nisin (N) on the quality of pompano (Trachinotus ovatus) were assessed throughout 15 days of storage at 4 ± 1 °C. Physicochemical (peroxide value, thiobarbituric acid, total volatile basic nitrogen, trimethylamine, pH, K value, texture, and color), sensory, and bacteriological characteristics of fish fillet were all periodically analyzed. RE + N treatment effectively improved physicochemical quality parameters and the sensory, and reduced microbial growth as compared with either treatment of RE or N alone or the control, which resulted in a significant extension in the shelf life of pompano fillet. Therefore, rosemary extract combined with nisin treatment may be a promising method of maintaining the storage quality and extending shelf life of pompano fillet during chilled storage.  相似文献   

10.
    
Dried salt-cured cod is a commercially important product that is mainly exported to markets in Latin America and Southern Europe. The product is usually split, and cut and packaged once it reaches the market. However, many markets do not have adequate refrigeration facilities. When stored at elevated temperatures, a red or pink discolouration can develop due to the growth of extreme halophiles, at which point the product is considered defective and cannot be sold. We have investigated the shelf life of packaged loins of dried salt-cured cod stored at 25, 30, and 35 °C and at 60 and 80% relative humidity (RH). Shelf life varied by temperature, RH, water content, and level of extreme halophiles. Product stored at 60% RH had a longer shelf life than product stored at 80% RH, and storage at 25 °C revealed a longer shelf life than storage at 30 or 35 °C. At both 60 and 80% RH, drying beyond 48% had a limited shelf life effect. As dried salt-cured fish is largely sold and consumed seasonally, its shelf life has more implications during the low season, as prolonged non-refrigerated storage may cause more product to become defective.  相似文献   

11.
    
《Food Control》2014,35(2):356-363
Three combinations of two natural organic acids, citric acid (CA) and lactic acid (LA), in the form of novel flake icing systems were evaluated for the preservation of European hake (Merluccius merluccius), one of the most commercialised gadoid fish species in Europe. The flake icing systems were prepared with fresh water and 0.075%/0.050% (C-75 batch), 0.125%/0.050% (C-125 batch) and 0.175%/0.050% (C-175 batch) CA/LA, respectively. Aerobic mesophiles, psychrotrophs, proteolytic bacteria, anaerobes, Enterobacteriaceae, trimethylamine, lipid hydrolysis, primary, secondary and tertiary lipid oxidation events, and pH levels were evaluated in hake muscle in all batches during 13 d of chilled storage and the results were compared with sensory analyses. Significantly (p < 0.05) lower microbial counts were found in the C-175 batch for all five microbial groups investigated when compared with the control batch, with differences between batches of greater than 2 log CFU/g in the case of aerobes and anaerobes. The presence of organic acids in the icing systems also inhibited (p < 0.05) the increase in trimethylamine-nitrogen (TMA-N) content, with greater inhibition as the CA concentration in the ice increased. An inhibitory effect (p < 0.05) on fluorescent compound formation due to the presence of organic acids in the icing systems, which is indicative of tertiary lipid oxidation, was also observed at advanced storage times. These results correlated well with sensory analysis, which revealed that the shelf lives of the C-125 and C-175 batches were extended. The melting of the ice crystals containing the natural organic acid solutions, especially in the C-175 batch, exerted an antimicrobial washing effect that may explain the better protection of hake quality when stored in the proposed flake icing system.  相似文献   

12.
    
《Food Control》2014,35(2):323-330
Blue-veined cheeses may allow Listeria monocytogenes survival and multiplication due to the biochemical characteristics of the cheese and the growth characteristics of the pathogen. Because of the availability of a considerable number of samples, we wanted this study to take a large view of the microbiota and of the incidence and genetic diversity of L. monocytogenes in blue-veined cheese rinds. Moreover, we wanted to determine if the pathogen present on the rinds at the end of ripening represented a risk to the consumer if the cheese should exceed the domestic storage limit imposed by Commission Regulation (EC) No 2073/2005 for food safety criteria.The rind microflora showed a high level of heterogeneity, and the incidence of L. monocytogenes (never found in the paste samples) was 55%, with an increased presence and concentration associated with a longer ripening time. Amplified Fragment Length Polymorphism (AFLP) was used to characterise L. monocytogenes isolated from blue-veined cheese rinds and highlighted the heterogeneity among the strains, demonstrating its suitability for studying the biodiversity of the pathogen in this environment. L. monocytogenes was able to grow during the shelf life of the cheese and was influenced by the refrigeration temperatures and the physicochemical characteristics of the cheese.  相似文献   

13.
The aim of this study was to evaluate the effects of oregano natural extract added to sheep burgers packaged in a modified atmosphere for 20 days at 2 ± 1 °C, seeking antioxidant properties and healthiness appeal. Antioxidant capacity of the oregano extract was determined by Folin-Ciocalteau, DPPH and FRAP methods. Three treatments of burgers were prepared: without antioxidant (control, CO), with 50 ppm BHT and with 1000 ppm oregano extract (ORE). The proximate composition (moisture, fat, protein and ash) of the meat product was determined and its stability was assessed through physicochemical (pH value, colour, lipid and protein oxidation, free fatty acids and volatile compounds profile), microbiological [total viable counts (TVC), Pseudomonas spp., Enterobacteriaceae, lactic acid bacteria (LAB)] and sensory analysis (5-point rating scale). ORE treatment presented similar counts of TVC and LAB and, also, an equivalent capacity to slow lipid and protein oxidation after 20 days, in comparison to BHT. The total amount of volatile compounds increased during storage (P < 0.01) and all treatments showed a decrease (P < 0.001) on a* value. However, ΔE0–20 was higher (P < 0.05) for CO treatment, indicating visual colour changes perceived by consumers. The presence of natural extract prevented the loss of sensory qualities in sheep burgers up to 15 days of storage, being that changes in off-odour were consistent with the microbial results that indicate burgers spoilage. In conclusion, oregano extract presented antioxidant effects quite similar to BHT and thus, can be considered a viable solution for the production of sheep burgers with a healthier appeal.  相似文献   

14.
    
Optimization of food preservation technologies is necessary for improved product quality and nutrition as well as energy and environmental sustainability. In the current study, inactivation of Bacillus subtilis spores in a model soup (pH 6.1) with agitating retort, static retort and combined high pressure-temperature treatments was investigated. With isothermal experiments, D95° C and z values for B. subtilis spores in the soup were obtained as 4.67 min and 8.65 °C. Log-linear model performed well for describing isothermal spore inactivation kinetics with satisfactory R2adj values (0.94–0.97). Agitating retort treatments caused a dramatic reduction in processing times, as 17 min processing in agitating mode was required for 7-log inactivation of B. subtilis spores, compared to 53 min in static mode at 110 °C. For agitating process, observed and predicted lethality values were similar. This implied a homogenous heat load distribution within the soup with the help of high frequency agitation. Combined HPP and mild temperature treatments were highly synergistic for elimination of B. subtilis spores in the same model soup used in heat treatments. HPP treatments combining 650 MPa and 55–65 °C for 10 min resulted in up to 4.5 log kill effect on spores. The findings from the current study can be utilized in selection of test conditions for similar products in future safety studies. Results clearly showed that using novel mechanisms in food processing provide an opportunity for milder processing which can lead to better food quality and sustainability.  相似文献   

15.
    
This study evaluated the efficacy of the individual treatments (slightly acidic electrolyzed water [SAcEW] or fumaric acid [FA]) and their combination to reduce Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Salmonella Typhimurium in fresh pork as well as to study the shelf life and sensory quality (color, odor, and texture) of pork during storage at 4 and 10 °C. The inoculated pork samples (10 g) were dipped for 3 min in each treatment (tap water [TW], SAcEW, strong acidic electrolyzed water [StAEW], 0.5% FA, or SAcEW + 0.5% FA) with or without mild heat (40 °C). Decontamination of fresh pork with SAcEW +0.5% FA at 40 °C for 3 min showed greater bactericidal effect compared to other treatments, which significantly (P < 0.05) reduced E. coli O157:H7, L. monocytogenes, S. aureus, and S. Typhimurium by 2.59, 2.69, 2.38, and 2.99 log CFU/g, respectively. This combined treatment significantly (P < 0.05) yielded in a longer lag time of naturally occurring bacteria (TBC) on pork stored at 4 °C. This combined treatment also prolonged the shelf life of pork up to 6 days and 4–5 days when stored at 4 °C and 10 °C, respectively, compared to those of the untreated pork. The results suggest that the combined treatment of SAcEW + 0.5% FA has potential as a novel method to enhance the microbial safety and quality of fresh pork.  相似文献   

16.
    
The official procedure adopted in Andalusia (Southern Spain) for implementing the hazard analysis and critical control points (HACCP) flexibility criteria for the control of the cold chain in the retail self-service sector set out in Regulation (CE) 852/2004 is based on a daily determination of the display temperature of the equipment. The main objective of our study was to test whether this approach was effective for the safety of the storage products, considering the influence of the position occupied by the foodstuffs inside the cooling equipment, and also possible seasonal fluctuations. The study was conducted in all self-service refrigerating equipments from every food retail store (11 supermarkets representing different national chain-store groups) located in various municipalities from Southern Spain. Statistically significant (p ≤ 0.05) breaches in the cold chain were recorded in the case of products located at the top shelf (TST) for all kinds of foodstuffs during the summer period, and also during winter time in the cases of TST of dairy products and refrigerated vegetables. Furthermore, using predictive microbiology as a tool, we calculated the potential reduction caused by those failures on the shelf life recorded in the food labelling of smoked salmon, cooked chicken breast and fresh cheese, which counted up to 40%, 57% and 25%, respectively. These findings show that the official procedure adopted does not ensure compliance with safety specifications of perishable food in the retail self-service sector. A revision of such procedure would be necessary, especially in those regions such as Andalusia where important temperature fluctuations throughout the year are recorded.  相似文献   

17.
    
Compared to most product supply chains, food supply chains are often more complex and more difficult to manage because the food product is perishable and has a short shelf life. A cold chain or temperature-controlled supply chain provides the essential facilities and methods required to maintain the quality and quantity of foods. Since foods can be time and temperature sensitive in nature, they need to be properly taken care of in terms of harvesting, preparation, packaging, transportation and handling – in other words, throughout the entire chain. Temperature is the most important factor in prolonging or maintaining the shelf life of perishables. Refrigeration is one of most widely used methods to date to slow the bacteria growth that leads to food deterioration. The proper control and management of temperature is crucial in delivering perishables to consumers and ensuring that those perishables are in good condition and safe to eat. This paper addresses the methods used to improve the ability to define an optimal target temperature for multi-commodity refrigerated storage. Simulation results support the fact that the presented methods provide more accurate results compared to the conventional method. In addition, an experiment with a Wireless Sensor Network (WSN) was conducted. As a result, the sensor-based methods for real time quality monitoring and assessment that consider product metabolism and Euclidean distance cost depending on temperature changes are found to be superior to the traditional visual assessment method.  相似文献   

18.
    
High hydrostatic pressure (HHP) is an old preservation method. However, there is still a gap in the literature about their promising conditions for improving the shelf life and quality of different fish groups (dark and white muscle) at different packaging systems (air and vacuum) stored under refrigeration. Since it is crucial to boost optimization research and enable HHP industrial commercialization, this study aimed to identify promising high hydrostatic pressure (HHP) conditions to extend the maximum fresh fish quality of dark and white muscle fillets stored under air-packing and vacuum-packing (DM-AP, DM-VP, WM-AP, and WM-VP, respectively), considering the bacteriological (total viable aerobic count), physicochemical (lipid oxidation, lightness, redness, yellowness, total color changes, and hardness or firmness), and sensory (appearance, color, odor, texture, and acceptability) characteristics during refrigerated storage. The systematic literature search was carried out in four databases (PubMed, Science Direct, Scopus, and Web of Science) to retrieve articles from 2001 to 2023 published in English. A total of 3,922 articles were retrieved, of which 49 were eligible for systematic review and 47 for meta-analysis. Overall, the best HHP conditions for DM-AP (400 MPa/5 min/5 °C) and DM-VP (400 MPa/5 min/20 °C) extended the microbial and sensory shelf life from about 6 to ≥ 9 days with a positive effect on color (ΔE ≤ 4). Concerning WM-AP, HHP at 220 MPa/10 min/25 °C and 250 MPa/5 min/3 °C did not affect lipid oxidation and extended the sensory acceptability by 2–4 days but negatively influenced hardness and color (ΔE > 5). For WM-VP, HHP at 300 MPa/3 or 10 min/10–20 °C could prolong the microbial and sensory shelf life by 7 days without affecting hardness, decreased lipid oxidation, and color changes (ΔE < 4). Therefore, HHP may enable the shelf life extension of dark and white muscle fish fillets stored under refrigeration in aerobiosis and vacuum while retaining their quality.  相似文献   

19.
The coating effects of tea polyphenol (TP) and rosemary extract (R) combined with chitosan (Ch) respectively on the quality of large yellow croaker (Pseudosciaena crocea) during refrigerated storage at (4 ± 1 °C) were evaluated. A solution of TP (0.2%, w/v) and R (0.2%, w/v) was used for dip pretreatment, and Ch (1.5%, w/v) was used for the coating. Microbiological (total viable count), physicochemical (pH, TVB-N, K value, PV, TBARS), and sensory attributes were periodically assessed over 20 days. The results indicated that the two dip pretreatments combined with chitosan coating could more effectively maintain the good quality and could extend the shelf life by 8-10 days compared with the control group during the refrigerated storage.  相似文献   

20.
    
This study aimed to optimize pectin extraction from crude cacao shell (CS) powder using chemical method (pH 4 and 10, temperatures 60–80 °C), ultrasound-assisted extraction (UAE) method (sonication time 20–40 min), and enzymatic method (pectinase 0.5–1.0% v/v, temperature 40–60 °C, and time 120–240 min). The optimal extraction condition with highest CS pectin yield was enzymatic followed by chemical and UAE methods. The pectin extracted from cocoa shell from all extraction methods had the degree of esterification (DE%) greater than 50% which was categorized as high methoxyl (HM) pectin. The prebiotic activity and viscosity of pectin from the optimal extraction conditions with highest pectin yield for each extraction method were studied. Pectin extracted via UAE method with highest prebiotic activity (p≤0.05), was selected for edible coating of tomato and quality changes were evaluated during 30 days of storage at 4 °C. The results showed that tomato coated with pectin-based edible coating (TWP) retained physicochemical properties (e.g., color, total soluble solid, pH, firmness, weight loss), and bioactivity (e.g., lycopene, total phenolic compound and antioxidant activity), compared with control (CON) and tomato coated with no pectin (TNP). In addition, the total viable count and yeast and mold count of TWP was the lowest among other treatments. Therefore, pectin-based edible coating was able to delay the quality changes and extend the shelf life of TWP sample up to 27 days at 4 °C.  相似文献   

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