Iced Storage Research Articles

The function of endogenous cathepsin in quality deterioration of grass carp (Ctenopharyngodon idella) fillets stored in chilling conditions

SummaryChanges of textural properties and cathepsin activity of grass carp fillets during storage in superchilling (−1.5 ± 0.2 °C) and ice (0.2 ± 0.1 °C) was investigated, and the function of cathepsin in quality deterioration of grass carp fillets was discussed. Results showed that shear force of superchilled and ice‐stored fillets decreased by 50% and 55% after 6 days of storage, respectively. The cathepsin activies in different fractions changed significantly during storage at both conditions. Cathepsin B, B+L activities in sarcoplasma, myofibrillar and heavy mitochondrial fraction significantly increased during the early 3 days postmortem, accompanied by remarkable reduction of corresponding activity in lysosome. Cathepsin D activity in sarcoplasma and myofibrillar significantly increased during 6 days of storage with corresponding decrease in lysosome and heavy mitochondria. Correlation analysis showed that changes of shear force of grass carp fillets were significantly correlated with integration of cathepsin B, D and B+L throughout storage time (r2 > 0.94). As derived from the first‐order exponential decay model, the enzyme efficiencies (ka) of cathepsin B and B+L were more than twofold higher than those of cathepsin D, suggesting the major role of cathepsin B and B+L in textural deterioration of grass carp fillets in chilling storage.

Interrelationship between myoglobin and lipid oxidations in oxeye scad (Selar boops) muscle during iced storage

The interrelationship between myoglobin oxidation, lipid oxidation and discolouration in oxeye scad fish during iced storage were investigated. The myoglobin autoxidation rate increased with increasing storage time up to 12days (p<0.05) and remained constant thereafter (p>0.05). Increase in metmyoglobin correlated well with a blue shift from 410 to 408nm for myoglobin. The soret band of myoglobin decreased with a concomitant decrease in the redness index (p<0.05). During storage, the extractable haem iron decreased (p<0.05), while the non-haem iron increased (p<0.05). Hydrogen peroxide and ferrylmyoglobin concentrations had increased at the end of storage (p<0.05). The conjugated diene (CD) and peroxide value (PV) of oxeye scad lipids tended to stabilise during the initial phase of storage, increased in the differentiation phase and had declined at the end of storage. However, thiobarbituric acid reactive substances (TBARS) increased markedly (p<0.05). Overall, lipid and myoglobin oxidations in oxeye scad occurred in a concurrent manner and each process appeared to enhance the other.

Postmortem Biochemical Changes and Evaluation of the Freshness in the Muscle of Tilapia (Oreochromis niloticus) during the Storage in Ice

Postmortem Biochemical Changes and Evaluation of the Freshness in the Muscle of Tilapia (Oreochromis niloticus) during the Storage in Ice

Volatile Compositions Analysis of Tilapia (&lt;i&gt;Oreochram niloticus&lt;/i&gt;) and Fishy Odour Development in the Muscle

Volatile compositions of fresh tilapia and fishy odour development in the muscle during 12 days of storage at-18°C were studied. Investigations were carried out to extract the volatile compounds in tilapia using solid phase microextraction (SPME). A total of 35, 35 and 38 volatile components were identified in the muscle, head and skin of tilapia, respectively, within which nonanal, octanal and E-octenal were the most powerful contributors to the fishy odour of Tilapia. During iced storage, free fatty acid (FFA) content, conjugated diene (CD) and thiobarbituric acid reactive substances (TBARS) increased. Peroxide value (PV) gradually decreased after increasing in the first 3days of storage. Total volatile basic nitrogen (TVBN) values increased from 7.7 to 24.1 mg/100g after the storage of 12 days. Correlations between chemical indexes and sensory evaluation scores showed that the off-odour in fish muscle was mostly governed by lipid oxidation.

Effect of iced-storage on the activity of cathepsin L and trypsin-like protease in carp dorsal muscle

Carps were stored in ice for 0, 2 and 4 days. The actomyosin was extracted from the ice-stored fish and the enzymatic activity of cathepsin L and trypsin-like protease in the extract was assayed. The two enzymes remained in the carp actomyosin despite intensive leaching during the extraction procedure. The activity of cathepsin L decreased slightly after 2 days of storage and remained relative constant thereafter, suggesting the enzyme was only slightly affected by the short term iced-storage. However the activity of the trypsin-like protease increased rapidly with iced-storage time, indicating that it might have been activated during the short term storage in ice.

Postmortem Changes of Crucian Carp (Carassius auratus) During Storage in Ice

Postmortem catabolism of Adenosine Triphosphate and Adenosine Triphosphate-related compounds, K value, pH, and texture of crucian carp were investigated during storage in ice. ATP and Adenosine Diphosphate degraded to Inosinic acid within 48 hours postmortem. There was a good relationship between pH value and IMP concentration (r = −0.753), IMP reached a top point at 3.33 ± 0.17 μmols/g in 4 hours postmortem; meanwhile, Hypoxanthine reached a bottom point at 0.038 ± 0.0052 μmol/g. K value increased linearly (r = 0.96) from an initial value of 0.54 to 1.66% in 48 hours postmortem. Texture analyses results suggested that rigor mortis lasted about 1 hour postmortem, after resolution of rigor, hardness, gumminess, and chewiness decreased in accordance with storage time (r = −0.88,−0.78, and −0.78, respectively). Those results indicated that it was better to effectively utilize the crucian carp in 2–4 hours postmortem. The K value might not be a good indicator to monitoring the loss of freshness of crucian carp during storage in ice since the K value was much lower than marine fish.

Nonprotein Nitrogenous Compounds and Gelling Property of Whitecheek Shark (C archarhinus Dussumieri ) Mince as Affected by Washing and Microbial Transglutaminase

Changes in nonprotein nitrogenous compounds and gelling properties of whitecheek shark (Carcharhinus dussumieri) meat during iced storage for 12 days were monitored. Total volatile base (TVB), trimethylamine (TMA) and ammonia contents increased, whereas urea content decreased during the storage (P < 0.05). TVB, TMA, urea and ammonia contents were lower in washed mince, indicating the removal of those compounds by washing. The addition of microbial transglutaminase (MTGase, 0.6 unit/g sample) was able to increase breaking force, deformation and water-holding capacity of both gels from mince and washed mince. Nevertheless, gel strengthening effect of MTGase was lowered when mince or washed mince were obtained from shark stored for an extended time. Polymerization of myosin heavy chain was enhanced when MTGase was incorporated but took place at a lower degree for mince and washed mince produced from unfresh shark. Washing process in combination with MTGase addition could therefore improve gel quality of shark meat. Practical Applications Shark meat is a good source of protein, which could be a suitable source for surimi production. However, the meat is considered to have a low market value because of undesirable odor, which is mainly from the decomposition of urea to ammonia during extended storage. Appropriate washing to remove those compounds, along with the use of microbial transglutaminase (MTGase), can be a promising means to improve the textural properties of gels from shark mince. Thus, shark meat can be better exploited, especially for the surimi industry.

Changes in the pericellular connective tissue and breaking strength of the three types of muscles of the cultured carp Cyprinus carpio during storage in ice

To elucidate the structural changes in pink (P), white (W), and red (R) muscles during storage in ice, we measured the breaking strength and changes in pericellular connective tissues of cultured carp. The breaking strength just after killing was highest in R muscle (1.00 ± 0.20 N), lowest in W muscle (0.37 ± 0.07 N), and intermediate (0.84 ± 0.12 N) in P muscle. During the storage period, the breaking strength decreased first in R muscle, then in P muscle, followed by W muscle. The diameter of muscle fibers was greater in W muscle (113 ± 15 μm) than in P muscle (72 ± 3 μm) and R muscle (48 ± 2 μm). Destruction of the honeycomb structure of the pericellular connective tissue occurred most rapidly in W muscle and most slowly in R muscle. These results suggest that the interposing of P muscle fibers in the dorsal ordinary muscle contributes to the acceleration of post-mortem tenderization in fish.

Biochemical, textural, microbiological and sensory attributes of gutted and ungutted sutchi catfish (Pangasianodon hypophthalmus) stored in ice.

Pangasianodon hypophthalmus (sutchi catfish) is a fresh water catfish extensively being cultured in the South East Asian countries in the recent years. The present study provides the first report on the effects of gutting on the quality characteristics of aquacultured sutchi catfish stored in ice. pH of whole ungutted and gutted catfish didn't show significant difference (p > 0.05) during ice storage period. Total Volatile Base Nitrogen (TVB-N), Alpha Amino Nitrogen (AAN), Free Fatty Acids (FFA) and Thio Barbituric Acid Reactive Substance (TBARS) were lower in gutted fish compared to whole ungutted fish at any particular day during ice storage. However, gutted fish expressed higher rate of primary lipid oxidation than ungutted fish. Textural degradation of the fish muscle as indicated by hardness, cohesiveness, springiness and chewiness was lower in gutted fish. Results of sensory evaluation revealed that gutting has significantly improved the sensory quality of the fish. However, microbiological analysis revealed higher Total Plate Count (TPC) and Enterobactereaceae count in gutted fish. The shelf life of gutted and whole ungutted sutchi cat fish as determined by microbiological analysis was 16-18days and 18-20days respectively while storage in ice.

Bacterial Diversity and Changes towards Spoilage Microflora of Iced Alaska Pink Salmon

Fresh, iced Alaska pink salmon were stored upto 20 days with samples of skin, gills and belly cavity analyzed for bacterial flora developments. Bacterial colonies isolated from plates used to estimate aerobic bacterial populations were identified using rapid cellular fatty acid analysis. Acidovorax spp. and Brevundimonas spp. were identified as part of the fresh fish microflora. The group consisting of Psychrobacter, Moraxella and Acinetobacter were present throughout salmon storage but were found only associated with fish skin and gills. Pseudomonas fluorescens and P. putida formed a major percentage of the spoilage flora and Shewanella putrefaciens comprised the minor portion in sampled tissues. The replacement of using the Sherlock Microbial Identification System for classical taxonomic tests resulted in time, material and labor savings. Also, the database provided a deeper view of the bacterial diversity and changes in bacterial flora that occurred during iced salmon storage.

Using the essential oil of Aloysia triphylla (L'Her.) Britton to sedate silver catfish (Rhamdia quelen) during transport improved the chemical and sensory qualities of the fish during storage in ice.

Exposure of silver catfish to 40 μL/L of the essential oil of Aloysia triphylla (AT) during in vivo transport delayed the onset and resolution of rigor mortis as well as the degradation of IMP into HxR compared to the control. The fish that were treated with 30 or 40 μL/L of AT received lower sensory demerit scores after 10 d of storage in ice compared to the control, and the fish that were treated with 40 μL/L of AT had a longer sensory shelf life than did the control. These results indicated that using AT as a sedative in the water in which the silver catfish were transported extended their freshness and increased their shelf life during refrigerated storage. Interest in natural anesthetics, such as Aloysia triphylla, has increased in the field of commercial aquaculture because they reduce the number of fish lesions acquired during capture, handling, and transportation. Fish sedated with the essential oil of A. triphylla at 40 μL/L during transport before slaughter exhibited a delay in the loss of freshness and an increased shelf life in ice. In addition to improving animal welfare before slaughter, the essential oil appears to be a promising product for improving fish conservation in the food industry.

Fatty acid composition, lipid oxidation, and fishy odour development in seabass (Lates calcarifer) skin during iced storage

Changes in fatty acid profile, lipid hydrolysis and oxidation, development of fishy odour and volatile compounds in seabass (Lates calcarifer) skin during 18 days of iced storage were investigated. Peroxide value (PV) increased up to Day 6 and subsequently decreased up to 18 days (p &lt; 0.05). The continuous increases in thiobarbituric acid reactive substances (TBARS) values, free fatty acid (FFA) content and lipoxygenase (LOX) activity were noticeable with increasing storage time (p &lt; 0.05). Formation of FFA and hydroperoxide was confirmed by the changes in amplitude of peak at 3600–3200/cm and 1711/cm in Fourier transform IR spectra, respectively. With increasing storage time, the increase in fishy odour intensity was observed along with the formation of volatiles. Hexanal and nonanal constituted as the dominant volatile aldehydes in skin stored in ice for an extended time. Therefore, the delay of skin processing must be avoided to prevent the formation of undesirable fishy odour in skin and its products.Practical applications: Seabass skin is one of the potential raw materials for production of collagen, gelatin or other derived products. Iced storage of seabass skin affected fatty acid composition, lipid hydrolysis and oxidation, development of fishy odour and volatile compounds. Therefore, skin from fresh fish should be used and the delay of further processing should be avoided to prevent undesirable fishy odour in skin and products made therefrom.During iced storage, seabass skin underwent lipid oxidation with the coincidental release or activation of LOX. Development of fishy odour took place along with the formation of volatile compounds.

English

Proximate composition and shelf-life studies of wild and pond-raised catfish (Clarias gariepinus) were determined using chemical, microbiological and sensory analyses. Proximate composition of both wild and pond-raised catfish showed differences in the lipid and protein levels. The pond-raised fish had higher lipid (6.30%) and protein (20.00%) than the wild fish lipid (4.48%) and protein (18.05%). Whole ungutted wild and pond-raised catfish was in good and satisfactory conditions for 17 and 22 days, respectively when stored in ice immediately after harvesting. There was no significant difference (p &gt; 0.05) in the storage life in ice of the wild and pond-raised catfish. The descriptive sensory evaluation showed that the fish underwent changes in eyes, gills, texture, odour and general appearance. The statistical analysis showed that the correlations between the cooked odour, texture and flavour of both samples were significant at p &lt; 0.05. The wild and pond-raised catfish showed a decline in sensory parameters during storage in ice with concomitant increase in bacteria counts and total volatile bases (TVB). The microbial population was dominated by bacilli, the counts ranged from 11.5 &times; 102 cfu/g to 15.4 &times; 102 cfu/g for wild catfish and 9.7 &times; 102 cfu/g to 11.1 &times; 102 cfu/g for the pond-raised catfish. Rejection of the catfish after 22 days was based mainly on rancid, putrid, feacal, ammoniacal and sulphide odours. TVB ranged from 2.41 to 20.50 mg/100 g for wild catfish and 2.86 to 22.88 mg/100 g for pond-raised catfish. &nbsp; Key words: Sensory changes, farmed Clarias, wild Clarias, shelf-life.

Evaluation of Quality and Shelf Life of Two Commercially Important Fish Species Viz., Tiger Tooth Croaker (Otolithes ruber Bloch and Schneider) and Flathead Grey Mullet (Mugil cephalus Linnaeus) in Iced Conditions

A study on the quality parameters to assess the shelf life of two commercially important species viz. Tiger tooth croaker and Flathead Grey mullet from different aquatic environments was carried out under iced conditions. Croaker, a marine species and grey mullet from brackish water sources was used for the study. Biochemical quality indices like non-protein nitrogen, total volatile basic nitrogen, peroxide value and free fatty acids were assessed. Changes in moisture, pH and K-value were also determined. For croaker, FFA values increased from the initial 2.2–20.1 % on 15 days of storage in ice, whereas in case of mullet it reached 17.9 % during the same period. During the same period the pH values showed an increase from 6.81 to 7.88 and from 6.68 to 7.53 in case of croaker and mullet respectively. TVBN and PV increased throughout the period of storage and the former crossed the limit of acceptability of 30 mg/100 g by 15 days in ice. The sensory evaluation based on demerit score system was carried out which showed that the species retained the high quality shelf life characteristics for 5 days in case of croaker and 7 days in case of mullet. However both the species remained in acceptable condition for a period of 13 days. Freshness index K-value for both species complemented the sensory evaluation scores.

Effect of Grape Seed Extracts on the Melanosis and Quality of Pacific White Shrimp (Litopenaeus vannamei) during Iced Storage

The aim of this study was to investigate the effect of grape seed extracts (GSE) at different concentrations (0, 7.5 and 15 g/L) on the melanosis formation and quality of Pacific white shrimp during 9 days of iced storage. The melanosis formation was significantly inhibited and sensory quality was significantly improved in shrimp treated by various concentration of GSE, compared with the control. The increase of pH, total volatile basic nitrogen content and the total bacteria amounts of shrimp treated by 7.5 and 15 g/L of GSE was significantly retarded. However, the melanosis score, total volatile basic nitrogen, and pH values of shrimp treated by 15 g/L of GSE was lower than that treated by 7.5 g/L of GSE. These results suggested that GSE could be used as an effective natural alternative to synthetic antimelanosic agents to inhibit postmortem melanosis and improve the quality of shrimp during iced storage.

Ultrastructural changes of cytochemical Mg2+-ATPase on three muscle types of cultured carp (Cyprinus carpio) during storage in ice

Ultrastructural changes of cytochemical Mg²⁺-ATPase on three muscle types of cultured carp (<i>Cyprinus carpio</i>) during storage in ice

Biochemical, Physical, Chemical, and Microbiological Assessment of Blue Shrimp (Litopenaeus stylirostris) Stored in Ice

Postmortem changes in blue shrimp (Litopenaeus stylirostris) muscle were studied on the basis of biochemical, chemical, physical, and microbiological changes during an 18 day storage period at 0°C. Adenosine 5′-triphosphate (ATP) content, breakdown products, K-value, pH, trimethylamine nitrogen (TMA-N), total volatile basic nitrogen (TVB-N), water holding capacity (WHC), color, and texture (shear force) changes were examined. Also, total mesophilic and psychrophilic bacterial counts were measured. K-value increased linearly (r2 = 0.98) from an initial value of 1.37 ± 0.59 to 59.42 ± 6.05% at Day 18. Spoilage indicators TVB-N and TMA-N increased from 29.56 ± 1.33 and 0.69 ± 0.25 to 39.04 and 2.04 ± 0.59 mg of N/100 g at Day 18, respectively; meanwhile, the total viable counts of mesophilic and psychrophilic bacteria increased from 3.48 ± 0.44 and 2.61 ± 0.29 log CFU/g to 6.27 ± 0.21 and 7.14 ± 0.39 log CFU/g, respectively, which indicated spoilage at the end of the storage period. The pH, texture, WHC, and color were affected (p < 0.05) during the storage period. Overall, results indicate that blue shrimp muscle quality was maintained for 12 days of storage in ice.

Microbiological evolution of gilthead sea bream (Sparus aurata) in Canary Islands during ice storage.

This study analyses the microbiological changes with traditional methods for total mesophilic aerobic, psychrotrophic, Aeromonas sp., Pseudomonas sp., Shewanella putrefaciens, Enterobacteriaceae, sulfide-reducing Clostridium and Photobacterium phosphoreum in muscle, skin and gills of whole ungutted gilthead sea bream (Sparus aurata) stored in ice during 18days. The muscle tissue showed the minor grade of contamination, followed by the skin and the gills, with statistic significance (p < 0.001). The most prominent microorganisms in the different tissues and at the end of the storage were Pseudomonas sp. (7.76, 10.11 and 10.40 log CFU/g), Aeromonas sp. (7.49, 8.24 and 9.02 log CFU/g) and S. putrefaciens (8.05, 7.49 and 8.05 log CFU/g) in sea bream harvested in the temperate water of the Canary Islands. The results obtained from this study can contribute to the improvement of microbiological knowledge of gilthead sea bream (Sparus aurata) by determining the evolution of microorganisms responsible for spoilage and their counts in different tissues such as muscle, skin, and gills during iced storage.

An alternative approach for improving freshness indices for squid (Loligo plei)

The leaching of soluble compounds reduces the efficiency of chemical indices for freshness when fish is stored in ice. The objective of this study was to evaluate whether chemical indices for freshness evaluation of squid (Loligo plei) could be improved by expressing their contents as percentages of the non-protein nitrogen (NPN). The contents of NPN, free amino groups (FAG), trimethylamine oxide (TMA-O), trimethylamine (TMA), volatile basic nitrogen (VBN), ammonia (AMM), urea and free tryptophan (FT) were periodically determined in squid muscle during 16 days of storage in ice. The VBN, AMM, TMA, urea and FT contents in squids, when expressed as mg/100 g, did not distinguish between squids stored in ice for 1 or 2 weeks. However, when the contents of VBN and AMM were expressed as percentages of the NPN, it was possible to distinguish between squids stored for 1, 4 and 7 days. Free tryptophan was the most efficient quality index for L. plei, allowing accurate discrimination of squids stored in ice for 02-...

Quality and shelf life assessment of Pacific white shrimp (Litopenaeus vannamei) freshly harvested and stored on ice

Pacific white shrimps (Litopenaeus vannamei) are an important shrimp aquaculture species worldwide. To quantify the quality and shelf life of untreated shrimp is imperative prior to the application of preservative treatments. In this paper, the quality and shelf life of Pacific white shrimp freshly harvested from three different farms and stored on ice for up to 12 days was investigated. The titratable acidity (TA) of shrimp specimens exhibited significant decreases (P < 0.05) whereas the metric chroma (C), total colour difference (TCD), aerobic plate count (APC), trimethylamine (TMA-N) and total volatile basic – nitrogen (TVB-N), peroxide value (PV) and p-anisidine value (AnV) exhibited significant increases during iced storage (P < 0.05). The TMA-N and TVB-N were significantly correlated whereas temporal TMA-N/TVB-N ratio increased considerably (P < 0.05). While the PV and AnV significantly correlated (P < 0.05), the temporal PV/AnV ratio depicted how primary and secondary lipid oxidation of Pacific white shrimp could relate during iced storage of 12 days. The shelf life of ice stored Pacific white shrimps was determined to be 8 days. The information gained by this study could serve as baseline for preservative treatments applied to fresh shrimps.