The Combined Efficacy of Superchilling and High CO2 Modified Atmosphere Packaging on Shelf Life and Quality of Swimming Crab (Portunus trituberculatus)

The combined effect of superchilling and modi?ed atmosphere packaging (MAP) treatment on the quality of swimming crab during storage was investigated. As a result, signi?cantly (p < 0.05) higher inhibitor effects on total aerobic plate counts (TPCs) were observed in MAP treatments than in control (air package). Additionally, chemical analysis results showed that MAP treatments with 40–80% carbon dioxide (CO₂) were highly effective in maintaining lower total volatile basic-nitrogen (TVB-N), trimethylamine-nitrogen (TMA-N), pH, and thiobarbituric acid reactive substances (TBARS) values in swimming crab (p < 0.05). On the other hand, the brightness (L*) results also con?rmed that this combined treatment showed a positive effect on the stability of color during storage. Results also indicated that the combination of superchilling and 60% CO₂ MAP treatment prolonged the shelf life of swimming crab to 15–20 days. However, 100% CO₂ MAP treatment showed a negative effect on the drip loss and overall acceptability, indicating CO₂ content should be considered as a critical factor in this promising technology.     

Different Packaging Conditions to Improve Shelf Life of Filleted Gilt-Head Sea Bream (Sparus aurata)

Abstract

Shelf life of cultured gilt-head sea bream fillets (Sparus aurata) in over-wrap, vacuum and gas mixture packages stored during 27 days at 1±1°C was compared. The gas mixtures used contained CO₂, O₂, and N₂ at different percentages (0% O₂ + 50% CO₂ + 50% N₂; 10% O₂ +50%CO₂ +40%N₂;20%O₂ +50%CO₂ +30%N₂;30%O₂ +50% CO₂ + 20% N₂).

The evolution of the freshness degree of the packaged fillets was carried out by measurements of total volatile bases (TVB), trimethylamine (TMA), Tiobarbituric Acid Reactives Substances (TBARS), K _i and H values, psychrotrophic bacterial counts and sensory evaluation (color, odor, flavor).

Fish fillets were obtained 3 hours after harvesting with the best handling practices. As a consequence of this, the initial bacterial load was very low. The inhibitory effect of CO₂ on bacterial growth was very effective, keeping very low counts throughout all the storage period. Gas packages without O₂ and vacuum packages presented very low oxidation, whereas TBARS values in over-wrap and 10%, 20% and 30% O₂packaged fillets increased according to the oxygen content in the package. K_i value and specially H value differentiated very well among aero-bically stored fillets, vacuum and modified atmosphere packaging. TVB and TMA productions were poor freshness indicators, since no differences were found among treatments. Sensory quality of fillets deteriorated faster in over-wrap than in vacuum and gas packages. Modified atmospheres containing 20 and 30% O₂ were given lower sensory scores than vacuum packages, since they gave rise to yellowness of the fillets and off-odors and off-flavors.

In summary, modified atmosphere packaging of filleted gilt-head sea breams with a gas mixture consisted of 50% CO₂ + 50% N₂ gave rise to an important extension of shelf life compared to over-wrap packaging, vacuum and modified atmosphere packaging with gas mixtures containing O₂. This was due to the very low oxidation levels produced during the storage, the lower H value as a consequence of a minor production of Hx and the great inhibition on microbial growth.     

Effect of CO2 on Chemical and Microbial Changes of Pacific White Shrimp During Modified Atmosphere Packaging

ABSTRACT

This study monitored the physical, chemical, and sensory quality of raw Pacific white shrimp (Litopenaeus vannamei) and the evolution of microbial flora under modified atmosphere packaging (MAP) with varying concentrations of CO₂ (95% CO₂/5% O₂; 80% CO₂/15% N₂/5% O₂; 65% CO₂/30% N₂/5% O₂) at 4°C during 10-day storage. Plate counts on selective agars indicated that MAP had a strong inhibitory effect on psychrotrophic bacteria, mesophilic bacteria, Enterobacteriaceae, and H₂S-producing bacteria. Analyses with molecular techniques (denaturing gradient gel electrophoresis, DGGE) by extracting bacterial DNA from shrimp samples showed that Vibrio spp. and Aeromonas spp. were predominant in fresh MAP samples. Shewanella putrefaciens, which dominated in samples stored in air, were found sporadically in MAP samples. Interestingly, lactic acid bacteria were not predominant in MAP samples, whose pH values were high (6.66 to 8.14) during storage. The content of total volatile basic nitrogen in MAP samples was about 10 mg N/g lower than the control at the end of storage. Higher lightness values and sensory scores were also observed in samples under MAP. However, MAP with CO₂ concentrations higher than 80% did not enhance the inhibitory effect on bacterial growth but induced more severe reddening and sensory quality loss.     

Effects of Modified Atmospheric Packaging Conditions on the Quality Changes of Pasteurized Oyster (Crassostrea belcheri) Meat during Chilled Storage

ABSTRACT

The effects of different atmospheric conditions on the quality and the shelf life of pasteurized oyster meat in chilled storage were investigated. The alternatives tested for pasteurized oyster meat were normal air (Control), 75% CO₂/25% N₂ (MAP-1), 75% CO₂/25% O₂ (MAP-2), 75% CO₂/5% O₂/20% N₂ (MAP-3), and vacuum packing (VP). The various observations of microbiological (total viable count (TVC), Enterobacteriaceae, Pseudomonas spp., lactic acid bacteria (LAB), and hydrogen sulfide–producing bacteria), physical (color coordinates L*, a*, and b*, and cutting strength), chemical (moisture, pH, total volatile basic nitrogen (TVB-N), peroxide value (PV), and thiobarbituric acid reactive substances (TBARS)) and sensory properties were performed every 3 days over a total of 27 days. During storage across all the treatments, L*, a*, cutting strength, pH, moisture content, and sensory scores decreased; whereas, b*, TVB-N, PV, TBARS, and microorganisms increased. However, among the various alternatives, MAP-1 had the best retention of oyster quality during storage. Based on sensory and microbiological qualities, the shelf lives in chilled storage were 9 days for control, 15 days for VP, 21 days for MAP-2 and MAP-3, and 24 days for MAP-1-treated cases.     

Quality and Shelf Life of Liver of Farmed Cod (Gadus morhua)

ABSTRACT

Livers of Atlantic cod (Gadus morhua) are traditionally used in cod liver oil production or consumed cooked or canned. The farming of cod is a relatively new industry in Norway. The aim of this study was to determine quality and shelf life of fresh liver from farmed cod during chilled storage on ice by hydrolysis and oxidation state and sensory quality and the influence on canned liver. In two experiments, livers from farmed cod were stored chilled and sampled from Days 0 to 13, respectively. Quality, measured as hydrolytic and oxidation degradation, was reduced after 7 days of storage, while sensory quality was reduced after 4 days. Free fatty acids increased from Day 7 in both experiments, while peroxide value and anisidine value showed no change when the livers were single wrapped. Rancid odor was the first sign of oxidation and was registered after three to four days of storage. Canning within 2 days of storage prevented leakage of oil from the canned livers. Sensory analyses of oxidation are recommended as a sensitive and rapid method to detect oxidation of chilled cod liver.     

Modified Atmosphere Packaging (MAP) for Control of Black Spot Formation in Chilled Prawns

The marketing of organically labeled prawns is predominately in a cooked or raw frozen form to avoid the development of melanosis (black spot). Certification for organic status prohibits the use of any added chemicals. The application of 60% CO₂/40%N₂ modified atmosphere to chilled (raw) prawns using two species of prawn was investigated for the ability to control black spot formation. Sensory assessment and microbiological counts were used to determine the end of product shelf life. Modified atmosphere packaged (MAP) prawns exhibited no melanosis for up to 16 days. The high quality life was retained for 12 days; shelf life of 16 days, according to standard microbiological criteria, was achieved, which is more than twice previously reported for non-MAP prawns. Results suggest MAP may be an effective method for the marketing of organically grown prawns as well as those produced by conventional prawn aquaculture without application of the normal chemicals used to prevent black spot.     

Quality Indices of Squid (Photololigo duvaucelii) and Cuttlefish (Sepia aculeata) Stored in Ice

The objective quality indices of squid (Photololigo duvaucelii) and cuttlefish (Sepia aculeata) stored in ice were compared with the subjective counterparts. Sensory (overall quality rating, quality index method [QIM], and multisample difference test), microbiological (total viable count [TVC], psychrophilic count), chemical (trichloroacetic acid-soluble peptide [TCA-soluble peptide], trimethylamine nitrogen [TMA-N], total volatile bases nitrogen [TVB-N], ammonia content, and protein pattern), and physical analyses (expressible drip, color, and texture) were determined in both species during 16 days of iced storage. As storage time increased, TCA-soluble peptide, TVB, ammonia content, and expressible drip were increased (p < 0.05). TMA content was markedly increased after 10 and 8 days of storage in squid and cuttlefish, respectively. Both TVC and psychrophilic count increased as the storage time increased (p < 0.01). Myosin heavy chain was degraded with coincidental decrease in shear force and sensory texture during storage (p < 0.05). According to the overall rating score, shelf life of both species in ice was estimated to be 6 days. The increases in ammonia content and expressible drip were highly correlated with the decrease in overall quality rating and increase in quality index score of squid and cuttlefish (p < 0.01).     

Precision and Application of Electronic Nose for Freshness Monitoring of Whole Redfish (Sebastes marinus) Stored in Ice and Modified Atmosphere Bulk Storage

Abstract

An electronic nose with electrochemical gas sensors (CO, NH₃, SO₂ and H₂S) was used as a rapid technique to monitor changes in the headspace of whole ungutted redfish (Sebastes marinus) stored in ice and under various conditions of modified atmosphere (MA) bulk storage (CO₂/N₂:60/40). The precision of the electronic nose measurements was determined using standard compounds (ethanol, trimethylamine, acetal-dehyde and dimethyldisulfide). The response of the CO sensor, suggesting the formation of alcohols and carbonyls, increased with time for both aerobic and MA storage and correlated well with sensory analysis using the Quality Index Method. Slower spoilage rate reflected by lower intensities of sensors' responses, lower microbial counts and less TMA production were observed in MA-stored redfish compared with aerobic storage in ice.     

Combined Effect of Ethanolic Coconut Husk Extract and Modified Atmospheric Packaging (MAP) in Extending the Shelf Life of Asian Sea Bass Slices

Combined impact of ethanolic coconut husk extract (ECHE) (200 ppm) and modified atmosphere packaging (MAP) with two separate gas mixtures [60% CO₂/30% N₂/10% O₂ (M1) and 80% CO₂/10% N₂/10% O₂ (M2)] on the shelf life of Asian sea bass slices during 4°C storage was investigated. Microbial load of slices was lowered when packaged under MAP, regardless of ECHE treatment, compared to the control (no ECHE treatment, packed in air). For control, slices treated with ECHE packaged in air, and samples packaged under M1, TVBC (total viable bacteria count) exceeded 6.0 log CFU/g at day 6, 9, and 12, respectively. TVBC of samples treated with 200-ppm ECHE and packaged under M1 and those packaged under M2 without and with ECHE treatment were lower than 6.0 log CFU/g at day 15. Peroxide and thiobarbituric acid reactive substances values in samples treated with ECHE, regardless of the packaging method, were lower than those kept under MAP and the control. Thus, shelf life extension of Asian sea bass slices could be achieved by treatment with 200-ppm ECHE in combination with M1 packaging, in which they could be stored longer than 15 days at 4°C.     

Effects of Additives and Packaging Method on Quality and Microbiological Characteristics in Mild Thermal Processed Fish Mince

The effect of adding 2% sodium lactate (NaL) premix to mild thermal processed fish mince, and the effect of packaging the product in vacuum, modified atmosphere (MA), or pretreated with soluble gas stabilization (SGS) prior to MA packaging were investigated. Adding 2% NaL premix significantly affected the color, and the bacterial load was significantly decreased compared to the control product, together with significant differences in the sensory score. Breaking force, firmness, stiffness, and gel strength were significantly increased by adding NaL, while no effect was found on head space gas composition, top web deflation, and pH. SGS significantly decreased the microbial load, but had no interaction effect with NaL. SGS significantly increased the amount of CO₂ in the head space gas, together with decreased top web deflation compared to modified packaging. Vacuum packaging significantly increased the breaking point, firmness, and stiffness and increased pH compared to MA and SGS. Addition of a NaL premix to minced fish products can be used successfully to increase shelf life without compromising other quality characteristics. SGS treatment before packaging in MA can successfully be used as an alternative to adding NaL with respect to microbiological product quality and without compromising other quality characteristics.     

Sensory Quality and Shelf Life of MAP Redfish (Sebastes marinus) Fillets as Affected by Previous MA Bulk Storage of Whole Fish

Abstract

The shelf life of iced redfish is known to be 16–19 days. This study evaluated the effects of modified atmosphere (CO₂/N₂: 60/40) in bulk storage of redfish and subsequent modified atmosphere packaging (MAP) of fillets. Fish were evaluated by sensory, microbiological and chemical methods. Modified atmosphere (MA) bulk storage of whole fish for more than 5 to 10 days did not improve their sensory quality or significantly increase shelf life. In fact, the study showed negative effects in texture and overall appearance. MAP of fillets processed from 10-day MA bulk stored fish showed a modest increase in shelf life, but negatively affected their texture. Sensory qualities, i.e., tenderness, that decreased under MA bulk storage were improved upon aerobic storage for fish stored under MA for 5 to 10 days, but not 14 days. Lower microbial levels were found in MA bulk stored fish and MAP fillets compared to traditionally iced fish, while higher TMA levels were found in MAP fillets.     

The Chemical and Sensory Quality of Smoked Sturgeon (Huso huso): A Case Study

In this study, the tail flesh of sturgeon acquired from the fish market in Be?ikta?-Istanbul, Turkey was put through hot smoking. The chemical composition of raw and smoked sturgeon was determined. The protein, lipid, ash, and moisture of the muscle tissue in raw and smoked sturgeon were found to be 17.63 to 17.49, 6.07 to 9.59, 0.79 to 2.71, and 75.42 to 68.40%, respectively. Both the raw fish and the smoked fish meat were categorized to possess high quality characteristics with pH, total volatile base nitrogen (TVB-N), and trimethylamine nitrogen (TMA-N) values. After smoking, the skin color lightness (L*) of raw fish was determined to decrease, while the flesh color lightness of raw fish was determined to increase. The redness (a*) and the yellowness (b*) of both the skin and the flesh were determined to increase. Sensory parameters of color, smoke aroma, flavor, texture, chewiness, and overall acceptance for smoked sturgeon was described as excellent and its flesh tasty.     

Effect of Marcela Extract (Achyroclines satureiodes) on the Shelf Life of Minced Tilapia (Oreochromis niloticus) Sausages

The effect of marcela extract (ME) on the shelf life of minced tilapia sausages was evaluated in this study. The level of phenolic compounds in the ME was 114.1 ± 2.9 mg GAE/g extract, and the DPPH free radical scavenging activity was 94.95 ± 1.34%. The ME protected the samples from color changes during storage. The addition of 0.5 and 0.75% ME significantly decreased lipid oxidation and microbial growth. The ME did not impact the sausages’ sensory quality, and the addition of 0.75% prevented sensory rejection during storage.     

Effect of the UV-C Radiation on Shelf Life of Vacuum-Packed Refrigerated Pirarucu (Arapaima gigas) Fillets

The effect of Ultraviolet radiation type C (UV-C) radiation (0.100 ± 0.010 J/cm²) on shelf life of Arapaima gigas fillets stored at 4 ± 1°C for 18 days was investigated. The samples were analyzed for total aerobic mesophilic bacteria (TAMB) counts; total aerobic psychrotrophic bacteria (TAPB) counts; Enterobacteriaceae; purge loss; pH; lipid oxidation; total volatile bases (TVB-N); ammonia; biogenic amines (BAs); and L*, a*, and b* values. UV-C radiation increased (P < 0.05) the generation time of all bacterial groups evaluated, increasing the shelf life by 2 days. UV-C-treated fillets showed lower (P < 0.05) L* values, purge loss, pH, TVB-N, ammonia, and BAs levels than their control counterparts throughout the storage period. Moreover, UV-C treatment did not result (P > 0.05) in detrimental effects on lipid oxidation or a* and b* values. UV-C at 0.100 J/cm² demonstrated a good potential for use in A. gigas fillets and, therefore, it could be applied at industrial scale.     

Effect of Packaging on Chemical Changes and Quality of Refrigerated Spot (Leiostomus xanthurus)

Spot (Leiostomus xanthurus) were overwrapped with Saran® (PVDC), vacuum skin packaged film-to-tray or film-to-film with Intact® skin packaging film (ISPF), or vacuum packaged film-to-film with surlyn and refrigerated at 4ºC for 15 days. ISPF packaged fish samples had significantly lower ammonia concentrations than overwrapped fish. No significant differences in pH or TBA values were determined among the investigated packaging materials. Vacuum packaging reduced microbiological shelf life of fish by approximately three days when compared to Saran® overwrap. ISPF film-to-film vacuum packaged fish had the longest sensory shelf life, while PVDC overwrapped fish had the shortest.     

Quality Attributes and Shelf Life Modeling of Pacific White Shrimp (Litopenaeus vannamei) Stored at Different Temperatures

ABSTRACT

To study and predict quality changes of Pacific white shrimp (Litopenaeus vannamei) during storage at different temperatures (273, 276, 279, 282, and 285 K), changes in quality of sensory assessment (SA), total aerobic counts (TAC), total volatile basic nitrogen (TVB-N), and K-value were determined. An Arrhenius model and a radial basis function neural network (RBFNN) model were built to predict quality changes of Pacific white shrimp, and the relative performances between the two models were compared. For the Arrhenius model, SA and K-values showed good performance in first-order reactions, while TAC and TVB-N showed good performance in zero-order reactions. The relative errors of the RBFNN model for all indicators were within 10%, but the range of relative errors based on the indicators of SA, TAC, TVB-N, and K-value were 1.68–81.20%, 5.54–25.50%, 2.58–71.06%, and 3.66–48.39%, respectively, for the Arrhenius model. Thus, the RBFNN model was more effective for predicting quality changes of Pacific white shrimp during storage between 273 and 285 K.