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Cholesterol is essential for a variety of functions in endocrine-related cells, including hormone and steroid production. We have reviewed the progress to date in research on the role of the main cholesterol-containing lipoproteins; low-density lipoprotein (LDL) and high-density lipoprotein (HDL), and their impact on intracellular cholesterol homeostasis and carcinogenic pathways in endocrine-related cancers. Neither LDL-cholesterol (LDL-C) nor HDL-cholesterol (HDL-C) was consistently associated with endocrine-related cancer risk. However, preclinical studies showed that LDL receptor plays a critical role in endocrine-related tumor cells, mainly by enhancing circulating LDL-C uptake and modulating tumorigenic signaling pathways. Although scavenger receptor type BI-mediated uptake of HDL could enhance cell proliferation in breast, prostate, and ovarian cancer, these effects may be counteracted by the antioxidant and anti-inflammatory properties of HDL. Moreover, 27-hydroxycholesterol a metabolite of cholesterol promotes tumorigenic processes in breast and epithelial thyroid cancer. Furthermore, statins have been reported to reduce the incidence of breast, prostate, pancreatic, and ovarian cancer in large clinical trials, in part because of their ability to lower cholesterol synthesis. Overall, cholesterol homeostasis deregulation in endocrine-related cancers offers new therapeutic opportunities, but more mechanistic studies are needed to translate the preclinical findings into clinical therapies.

Cholesterol mediates its proliferative and metastatic effects via the metabolite 27-hydroxycholesterol (27-HC), at least in breast and endometrial cancer. We determined the serum lipoprotein profile, intratumoral cholesterol and 27-HC levels in a cohort of patients with well-differentiated papillary thyroid carcinoma (PTC; low/intermediate and high risk), advanced thyroid cancers (poorly differentiated, PDTC and anaplastic thyroid carcinoma, ATC) and benign thyroid tumors, as well as the expression of genes involved in cholesterol metabolism. We investigated the gene expression profile, cellular proliferation, and migration in Nthy-ori 3.1 and CAL-62 cell lines loaded with human low-density lipoprotein (LDL). Patients with more aggressive tumors (high-risk PTC and PDTC/ATC) showed a decrease in blood LDL cholesterol and apolipoprotein B. These changes were associated with an increase in the expression of the thyroid’s LDL receptor, whereas 3-hydroxy-3-methylglutaryl-CoA reductase and 25-hydroxycholesterol 7-alpha-hydroxylase were downregulated, with an intratumoral increase of the 27-HC metabolite. Furthermore, LDL promoted proliferation in both the Nthy-ori 3.1 and CAL-62 thyroid cellular models, but only in ATC cells was its cellular migration increased significantly. We conclude that cholesterol and intratumoral accumulation of 27-HC promote the aggressive behavior process of PTC. Targeting cholesterol metabolism could be a new therapeutic strategy in thyroid tumors with poor prognosis.

The quality of whole ungutted bigeye tuna (Thunnus obesus) during bulk storage in controlled atmospheres containing either of two gas mixes (60%CO 2/15%O2/25%N2 and 40%CO2/40%O 2/20%N2) was evaluated by biochemical and sensory changes. At day 33 of storage, none of the lots were rejected on the basis of the target biochemical indices (pH, trimethylamine nitrogen (TMA-N), total volatile base nitrogen (TVB-N) and histamine) or the tasting panel scores. However, the control and the controlled atmosphere-stored lots were rejected upon inspection at 13 and 22 days, respectively. Scores for the various target biochemical parameters were highest (p

This paper presents the examination of the evolution of biochemical, sensory and microbiological changes occurring in hake slices stored in modified atmospheres containing three gas mixes. It also shows how these changes relate to changes in the concentrations of the gas mixes in the tray packs during storage. At the outset of storage, there was a pronounced drop in the level of CO2, associated with lowering of the pH and lower scores for texture in sensory inspection. Nevertheless, by the end of storage, CO2 concentrations had increased. This was associated with growth of Enterobacteriaceae and with more pronounced decreases of O2, which is consumed by these microorganisms. Weight loss was greater in the atmosphere-stored lots, possibly due to the action of CO2. TMA-N and TVB-N began to increase on days 10 and 13 of storage and reached the permitted limits on days 17 and 20. Our analyses revealed no appreciable differences of performance between the different gas mixes, possibly because the gas levels were very similar in the various lots throughout storage. © Springer-Verlag 2003.

Changes in free amino acids (FAA) in hake stored in a combined system of atmospheres were studied together with the chemical index (pH, TVBN, and TBA) and sensory changes during chilled storage. Fluctuations or constant levels were observed in most of the FAAs throughout storage. There was only a progressive change throughout storage for tryptophan, β-alanine, methylhistidine, and anserine. At the end of storage, the lots packed in atmospheres with air had the lowest levels of tryptophan, β-alanine, methylhistidine, and anserine and the highest levels of TVBN and pH. The high levels of glutamic acid, glycine, and alanine from d 0 until d 24 of storage seem to be related to the sensory analysis results., This work was supported by the projects AIR1 CT92–0273 UE and ALI93–1004-EC (C.I.C.Y.T.).

Sensory, chemical and bacteriological changes were studied in vacuum-packed squid mantles (Todaropsis eblanae) that were pressurised at 150, 200, 300 and 400 megapascal (MPa) for 15 min at ambient temperature and stored at 4°C. Sensory analysis showed that the higher the pressurisation the longer the shelf-life. Thus, the lot pressurised at 400 MPa was rejected after 28 days' storage compared with 7 days for the untreated lot. The chemical results generally corresponded with the sensory ones. Furthermore, ammonia (NH3) and trimethylamine (TMA) were produced in the pressurised lots after a pressure dependent delay. Urea decreased to low levels in all lots with the exception of the 400 MPa lot. Onset of production of agmatine, the dominant amine in this species, and other biogenic amines was delayed by increasing pressure, but still, high concentrations of these amines were detected in pressurised lots of acceptable sensory quality. Microbial counts conducted after 1 day of storage showed that the bacterial load was reduced by all pressures, reaching levels below the detection limit in the lots treated with 200-400 MPa. However, growth was resumed in all lots after a pressure dependent delay. Luminous bacteria predominated initially in the lots pressurised at 300 and 400 MPa, but were outnumbered by Enterobacteriaceae and lactic acid bacteria at the time of sensory rejection of these lots. All colonies isolated prior to pressurisation were identified as Photobacterium phosphoreum. This bacterium also resumed growth faster than other members of the endogenous microflora after pressurisation. All luminous colonies were identified as P. phosphoreum. Lactic acid bacteria isolated at the final sampling point of the lot pressurised at 400 MPa were identified as Carnobacterium piscicola and Carnobacterium divergens, while Serratia liquefaciens and Proteus vulgaris make up Enterobacteriaceae. © 2002 Elsevier Science B.V. All rights reserved.

Whole ungutted pota and octopus were stored in bulk in stainless steel refrigerated containers under controlled atmospheres. In order to evaluate the effectiveness of this treatment, physicochemical tests (pH, trimethylamine nitrogen, total volatile basic nitrogen, 2-thiobarbituric acid) and sensory assessments (inspection) were done. For both pota and octopus, the control lot had the highest physicochemical values and the lowest sensory values, and of the two assayed atmospheres, the 60/15/25% atmosphere (CO2/O2/N2) had the best physicochemical results. pH, trimethylamine nitrogen, and total volatile basic nitrogen levels were lower (P < or = 0.05) in octopus than in pota, and the inspection results were significantly (P < or = 0.05) higher. However, the octopus had a higher 2-thiobarbituric acid index than the pota. Therefore, the application of controlled atmospheres on these cephalopods during chilled bulk storage considerably increases their shelf life.

Whole gutted hake kept in a controlled atmosphere (60% CO 2 /15% O 2 /25% N 2 ) for 7 and 12 days in containers in the hold of the fishing vessel and then stored conventionally in ice was compared with hake stored in ice and treated in the traditional way. The residual effect of the atmosphere containing CO 2 prolonged the shelf-life of chilled hake by 2-5 days compared with that of hake stored in ice. This residual effect of CO 2 was dependent on the period of time in the controlled atmosphere; 12 days in this atmosphere was the optimum to obtain the maximum residual effect of CO 2 . On day 25 the legal limit of total volatile basic nitrogen (TVBN) was reached in hake previously kept under the controlled atmosphere for 12 days (CA12), and the hake was also rejected in the inspection and pH analyses. However, this lot did not reach the legal limit of trimethylamine nitrogen (TMA-N) during the 25 days of storage. Similar results were found by a sensory panel, who rated the hake kept in controlled atmosphere storage (CA12) well. Les atmospheres controlees seraient tres utiles a bord des bâteaux de peche lors de sorties en mer de 15-20 jours, pour prolonger la duree de conservation des poissons. Le sujet de cette etude est d'examiner l'effet residuel du CO 2 sur le merlu entier eviscere, entrepose dans la glace et traite par les voies traditionnelles en comparaison avec le merlu conserve a bord d'un bâteau pendant 7 a 12 jours sous atmosphere controlee (60% CO 2 , 15% O 2 , 25% N 2 ) et dans la glace. Ce traitement est efficace et economiquement viable pour des durees d'entreposage superieures a 16 jours.

Changes in biogenic amines (tyramine, histamine, putrescine, cadaverine, agmatine and spermidine) contents during the storage of chilled hake in a controlled atmosphere with four gas mixtures of different CO2 and O2 concentrations, (CO2/O2/N2 at 60/15/25, 40/40/20, 60/40/0 and 40/60/0 respectively) were studied. Biogenic amines were determined by high-pressure liquid chromatography with post-column derivatization and ortho-phtaldehyde. Histamine levels, potentially the most toxic amine in hake, were very low during storage. The amine in hake with the highest level was cadaverine. Spermidine and putrescine had very high levels at the beginning of the storage. However, agmatine and tyramine were not detected in the source raw material. An increase in biogenic amines was observed in the control lot from day 12 of storage except for agmatine, where levels began to increase earlier. Cadaverine and agmatine could be used as control indices due to their behaviour during the storage period studied. The varying O2 and CO2 concentrations in the different atmospheres did not seem to affect the production of spermidine. The high levels of CO2 in thelot in M1 atmosphere were not sufficient to inhibit the production of biogenic amines. However, the high O2 concentration had an inhibiting effect on the production of biogenic amines. Therefore, the formation of biogenic amines was inhibited by controlled atmospheres with oxygen-enriched binary gas mixtures. © Springer-Verlag 2001.

This paper examines the evolution of FAAs in hake stored in ice and kept in controlled atmospheres for 33 days with four different gas mixes (CO2/O2/N2): M1 (60/15/25), M3 (40/40/20), M4 (60/40/0), and M5 (40/60/0). The most abundant FAAs in hake muscle are threonine, glutamic acid, glycine, alanine, β-alanine, tryptophan, 1-methylhistidine, and anserine. Anserine was the compound initially present in the highest concentration (61.65 mg/100 g of fish wet weight). As storage progressed, anserine concentrations fell, the smallest decrease being found in the lot kept in M1. At the end of storage the lot with the lowest level of anserine was M5C, which contained the highest O2 levels. The levels in the other lots were very similar. This fall in anserine coincided with an increase in 1-methylhistidine and β-alanine, the two amino acids to which it becomes hydrolyzed. As well as the fall in anserine, there was a progressive increase in muscle tryptophan during storage of the hake. This increase became more pronounced from day 12 of storage and was greatest in the control and lots M1C and M3C, which relates to the results of the other biochemical indexes. Both anserine and tryptophan could be used as quality control indexes for chilled hake. In general, no clear relationship was found between the effect of the atmosphere and the behavior of the FAAs.

Changes in free amino acids (FAAs) in relation to freshness were examined in the muscle of Norway lobster during bulk storage in controlled and modified atmospheres containing two different gas mixes (1:60/15/25 and 2:40/40/20, CO2%/O2%/N2%). The essential free amino acids in the highest concentrations were threonine, leucine, valine, lysine and arginine, all over 40 mg/100 g. Threonine, valine, lysine and arginine concentrations decreased significantly (p

Free amino acids (FAAs) and biogenic amines were determined in whole hake (Merluccius merluccius L) stored in bulk under controlled or modified atmosphere (60% CO2:15% O2:25% N2) for 12 days at 2°C and followed by storage in trays either under the same special atmosphere or under air for 31 days at 2°C, which was the control. At the end of the storage, significant differences were observed (P≤0.05) in the amino acids isoleucine, leucine, methionine, phenylalanine, valine, glutamic acid and glycine between the control lot and the treated lots, and it was the control lot which exhibited the highest concentrations. However, the lots kept in special atmospheres exhibited higher levels of alanine, β-alanine, threonine, and tryptophan than the control lot. There was no relationship between the decreases in histidine, tyrosine, lysine, arginine and ornithine initial concentrations and the increases in their corresponding biogenic amine concentrations (histamine, tyramine, cadaverine, agmatine and putrescine, respectively) which appeared as a result of decomposition of fish by decarboxylation of the FAA. Significant differences (P≤0.05) were observed in the biogenic amine concentrations among the lots kept under special atmospheres. The bulk-stored lot in controlled atmosphere for the first 12 days and then packed in trays with modified atmospheres exhibited the lowest levels of biogenic amines, except for agmatine, throughout storage. © Springer-Verlag 2002.

Functional properties of muscle proteins of volador (Illex coindetii) were evaluated during frozen storage and classified according to gender and anatomical part of the animal. Solubility of protein in 5% NaCl, in all lots, showed a significant increase in the initial months and then a decrease. This solubility was generally greater in the mantles than in the arms. The viscosity was initially very high and fell rapidly, and there were no significant differences between the lots. This initial viscosity was greater in the arm lots than in the mantle ones. Likewise, extracts of the muscle of the arms also had the greatest initial emulsifying capacity values (P≤0.05). Soluble collagen, in an acid medium-exhibited a similar trend in all lots, throughout frozen storage. At the early stages of storage, soluble collagen remained stable or increased slightly, and then tended to become insoluble. The lowest solubilities were for the muscles of the arms. Myofibrillar protein and collagen solubilities, as well as emulsifying capacities were effective for detecting molecular changes in the proteins during frozen storage and results showed that, the volador mantles were more suited to frozen storage than the arms. Copyright © 2002 Elsevier Science Ltd.

A characterisation of non-protein nitrogen (NPN) was carried out in the muscle of three species of cephalopods: volador (Illex coindetii), pota (Todaropsis eblanae) and octopus (Eledone cirrhosa). These species were classified according to sex, sexual development (immature, mature) and anatomical zone (mantle, arms). There were no major differences in the NPN contents of the three species studied. The anatomical zone clearly marks the difference in NPN content, with the content being greater in the mantle than in the arms for all the species. The trimethylamine oxide-nitrogen levels in volador were greater in the mantle than in the arms and these differences were not observed in the other two species. In pota and octopus, however, it is the stage of sexual development that exhibited differences, with a greater quantity of trimethylamine oxide-nitrogen in the immature specimens than the mature ones. The trimethlyl and total volatile basic nitrogen behaviour had no clear trend, the TVB-N levels were probably so low that these differences were not important. The same thing occurred with the pH, where the lowest values were recorded in octopus and the highest in pota. The free amino acid (FAA) compositions varied to a great extent, depending on the species and, to a less extent, depending on the sex, stage of sexual development and anatomical zone. The total FAA content was virtually the same in volador and pota, while it was about 75% lower in octopus. The highest concentrations of FAA in the three species were for proline, arginine and alanine, but in different proportions. © 2002 Elsevier Science Ltd. All rights reserved.

A luminescent colony isolated from spoiled hake, tentatively identified as Photobacterium phosphoreum, was cultured in a sterile fish juice at 1±1 °C. Growth, trimethylamine, off-odour and biogenic amines production under four gas mixtures (60% CO2/15% O2/25% N2, 60% CO2/40% O2, 40% CO2/60% O2, 40% CO2/40% O2/20% N2) and under air were tested. Aerobically incubated bacteria showed the highest counts and trimethylamine production after 43 days of storage (>108 cfu/ml and 28 mg TMA-N/100 ml, respectively). Mixtures containing CO2 and O 2 seemed to exert an inhibitory effect both on growth and trimethylamine production by this bacteria, specially for mixtures containing 60% CO2. Off-odour production was detected when the bacteria was incubated in air from day 15. Cadaverine was the major amine produced by P. phosphoreum followed by histamine. Putrescine and spermidine production generally increased during the aerobic incubation. However, the level of histamine and tyramine was higher under the gas mixture containing 60% CO 2/15% O2/25% N2 than in air, whereas the agmatine production seemed to be enhanced under any gas mixture assayed. © Springer-Verlag 2002., This work was carried out under projects CT92–0273 and ALI93–1004-CE.

The residual effect of CO2 on whole gutted hake kept with three different CO2/O2/N2 gas mixtures: 60/15/25, 80/20/0 and 40/40/20, and two different kinds of atmospheres (controlled and modified) during 12 days followed by conventional storage in ice for up to 30 days was examined by physical, chemical and sensory analyses. Shelf life was longer in lots kept in atmospheres than in control lots and was further prolonged by controlled than by modified atmospheres. The lots kept in the atmosphere with the highest concentrations (80%) of CO2 exhibited the lowest trimethylamine nitrogen and total volatile basic nitrogen values. However, these were also the lots that scored worst in sensory analysis. The lots that scored best in sensory analysis were those which were kept in the gas mixtures with 60% and 40% of CO2. Oxidative rancidity was not a problem in the samples stored in the atmosphere with 40% O2; Thiobarbituric acid levels were lower than 2 mg/100 g in all lots throughout storage, and the assessors detected no rancidity. The residual effect of CO2 on whole gutted hake was more effective in controlled atmosphere lots., The experiment reported here is a part of the project “Maintaining quality of fresh fish aboard ship and on land by modified atmosphere. Development of equipment, containers and procedures” contract no. AIR1 CT92-0273 EU and ALI93-1004-CE (C.I.C.Y.T.).

Whole gutted hake was stored for 25 days in ice. Changes in pH, trimethylamine nitrogen (TMA-N), total volatile basic nitrogen (TVB-N), and lipid deterioration [2-thiobarbituric acid (TBA) index] was studied, and correlated with sensory analysis (inspection and tasting). There was a very high correlation between TMA-N and TVB-N indices. TBA levels remained very low throughout the assay and were correlated with the results found in the tasting analysis, where the tasters did not detect any rancidity. However, the TBA results had a very low correlation with the inspection analysis and the TMA-N and TVB-N analyses. The pH, TMA-N and TVB-N indices had a very high correlation with the sensory analyses, which means these parameters are more suitable as indices for spoilage of hake. © 2001 Elsevier Science Ltd., This work has been financed by the project AIR1 CT92-0273 UE and ALI93-1004-EC (C.I.C.Y.T.).

The production of biogenic amines in the lots of whole hake stored bulk under a controlled or modified atmosphere for 12 days with the gas mixture 40% CO2:40% O2:20% N2 and after packing in trays under a modified atmosphere in the same mixture of gases or with air was studied. Results indicated a close relation between the development of trimethylamine nitrogen (TMA-N) and the sensory parameters gill appearance and odor but not with the general appearance of the skin and eyes. These results were related to changes observed in the concentration of gases (CO2 and O2) during storage containers and trays. The lot of bulk-stored whole hake in controlled atmospheres for 12 days with the gas mixture 40% CO2:40% O2:20% N2 and then packed in trays with the same atmosphere exhibited TMA-N levels below the 12.5 mg/100 g limit designated by the legislation in force (Directive 91/143/EU) on day 31 of storage when the sensory parameters general appearance and skin and gill color were not rejected. Histamine and tyramine levels were less than 1 mg/kg, putrescine levels were approximately 7 mg/kg, and cadaverine and agmatine levels were 33.91 and 20.33 mg/100 g, respectively.

Growth, trimethylamine (TMA), off-odour and biogenic amine production by a strain of Shewanella putrefaciens isolated from spoiled hake (Merluccius merluccius L.) and cultured in a model system, were tested under four different gas compositions (60% CO2/40% O2, 60% CO2/15% O2/25% N2, 40% CO2/60% O2, 40% CO2/40% O2/20% N2) and under air. After 3 weeks of incubation, the control (air) batch showed the highest microbial counts (>9 log cfu/ml) and TMA concentrations (45 mg N-TMA/100 ml), and strong putrid off-odours were detected from day 15. High amounts of putrescine and cadaverine were produced in this batch, but histamine increased only slightly. Batches under controlled atmospheres showed reduced growth, TMA, off-odour and biogenic amine production. The 40% CO2/60% O2 mixture had the strongest inhibitory effect on bacterial growth, while the 60% CO2/15% O2/25% N2 mixture was less effective. Putrescine and histamine production was lowest in S. putrefaciens under the 40% CO2/60% O2 mixture. However, the level of histamine in S. putrefaciens was higher under 40% CO2/40% O2/20% N2 than when the bacteria was incubated in air. Under the gas mixtures, there was a similar decrease in the production of cadaverine and agmatine by S. putrefaciens, irrespective of the gas concentrations. The production of 2-phenylethylamine appeared to be inhibited under any atmospheric condition. Copyright © 2001 Elsevier Science B.V., This work has been carried out under project AIR, EC contract no. CT92-0273, Spanish National Plan ALI 93-1004-CE

This work compares hake gutted whole and placed in boxes in ice under controlled atmospheres (CA) with four different gas mixtures: M1 CO2/O2/N2(%) (60/15/25), M3 (40/40/20), M4 (60/40/0) and M5 (40/60/0) and hake in air for 33 days of storage. The storage chamber temperature was 0 ± 1°C. Biochemical analyses [pH, total volatile basic nitrogen (TVB-N), trimethylamine nitrogen (TMA-N) and thiobarbituric acid (TBA index) and sensory analyses (inspection and tasting)] were carried out to study the quality of the hake. The hake, kept under controlled atmospheres, did not exceed the limits for acceptability of 35 mg/100 g and 12 mg/100 g of TVB-N and TMA-N, respectively, throughout the storage period, and the TBA values remained lower than the recommended limits of 14 mg of malonaldehyde/100 g. Chemical results accorded with the tasters who did not detect any off-odour in the samples, and the M4C lots stored under 60/40/0 (CO2/O2/N2%) was rated the best. However, this result did not accord with the inspection or pH by which all the lots were rejected at day 25 of storage. Despite this, the atmosphere system for preservation of chilled hake could be used safely and effectively on fishing boats to extend the shelf life of this species, and was better than conventional storage in ice. © 2001 Elsevier Science Ltd. All rights reserved.

Changes in fatty acid composition in both fresh and frozen sardine during mixed smoking (2h at 30°C and 45rain at 75°C) were studied. After extraction, the lipids from unsmoked and smoked sardine were separated into the three main fractions ( triglyeerides, phospholipids, and free fatty acids) by thin-layer chromatography; the fatty acids were then analyzed using gas chromatography. Oxidation during smoking brought about losses in the proportion of the long-chain n-3C2o and Czz fatty acids, as determined by increases in the peroxide value and in the 2-thiobarbituric acid index. On the other hand, the above polyunsaturated long-chain .fatty acids in some eonditions increased in frozen sardine, because of extraction-related effects caused by weakening of the protein-lipid linkages.

The effect of fat content and storage temperature on the biochemical and organoleptic alterations taking place during storage of smoked sardine fillets (made from sardines which were stored for three and six months at −18°C prior to being smoked and the influence of such alterations on product storage life were studied). During storage at 1°C, softening was the factor most affecting storage life in the smoked batches made from sardine frozen for three months prior to smoking or from sardine with higher fat content. In contrast, rancidity was the primary factor limiting storage life in the smoked batches made from sardine with lower lipid content and in the batches stored at −18°C. In the smoked batches made from sardines with lower fat content frozen for six months prior to smoking, the level of oxidation in the raw material was the main factor limiting the storage life of the smoked fillets; organoleptic rancidity was more perceptible in the smoked fillets stored at −18°C on account of a sharp drop in smoked flavour.

Rainbow trout fillets, dorsal fillets, and minces made from the ventral and caudal portions cut away from the dorsal fillets and from the waste portions after filleting, vacuum packed and either untreated or treated with additives (3% sorbitol + 0.5% MSG + 0.02% BHA + BHT (fat content)), were found to be suitable for consumption after one year's storage at −18°C. Since all the lots were well-preserved under these storage conditions, they may be appropriate for marketing trout products.

The effect of mixed smoking (2 h at 30° C and 45 min at 75° C) on lipids in lean sardine caught in the Mediterranean Sea in March was studied. The peroxide value, 2-thiobarbituric acid index, content of nonesterified and free fatty acid were used as measures of rancidity. Changes in the fatty acid composition in the total fat and various fat fractions were also examined. Smoking resulted in increases in the peroxide value, the thiobarbituric acid index and fatty acid content because of rancidification taking place during processing. Such rancidification caused alterations in the relative percentage composition of the different lipid fractions, with significant decreases recorded in the triacylglycerols and phospholipids along with a concomitant increase in the nonesterified free fatty acids. Fatty acid composition also underwent changes, mainly a certain decrease in the polyunsaturated long-chain fatty acids (C20 and C22) of the family n-3, so important in nutrition. © 1989 Springer-Verlag.

The effect of mixed smoking (2 h at 30 °C and 45 min at 75°C was studied on the keeping quality of lean and fatty sardine fillets from fish caught in the Mediterranean Sea in March and June, respectively. Raw material for smoking included both fresh and frozen sardine fillets. Microbiological and sensory analyses were performed over the storage period, which lasted for 120 days at 0 ± 1 °C. Smoking reduced the viable microbial flora values from 3-5 x 104 cfu/g to 2 × 102 cfu/g. The antimicrobial action of smoking, combined with that of vacuum packaging, had the effect of producing a gram-positive flora made up mainly of lactic acid bacteria. A practical consequence of this was to extend the shelf life of the smoked sardines for a period of 4 months. Frozen storage of samples at -18 °C for 6 months prior to smoking affected the behaviour of the microbial flora during cold storage at 0 °C, but did not affect the behaviour of the flora over a period of 3 months frozen storage, since the initial numbers of bacteria decreased and microbial growth was retarded. Furthermore, at the end of the storage period, the number of bacteria in the samples of frozen fatty sardines were higher than in the samples of frozen lean sardine. Physical conditions, therefore appear to exert an influence on bacterial growth. Sulphite-reducing Clostridia were not detected during the storage period. © 1989 Springer-Verlag.

Minced trout, either untreated or treated with additives (3% sorbitol + 0.5% MSG + 0.02% BHA + BHT (fat content)), was found to be acceptable over one year's storage at either −12, −18, or −24°C. The treated samples maintained optimum quality levels over the entire period at each of the storage temperatures tested. Quality was assessed by both objective and subjective methods.

[EN]: Samples of squid were subjected to five different methods of preparation and were then kept at -20°C for 408 days. The texture, as measured by sensory, instrumental and chemical methods, was maintained for all samples and no rancid flavour or odour was found. No melanosis was detected, but if thawed material was held at a chill temperature for three days melanosis then appeared in all batches which were not skinned., [FR]: Pour déterminer le comportement à l'entreposage de calmar et essayer d'éviter la mélanose, on a constitué 5 lots (entier, éviscéré, manteau, entier traité au métabisulfite et tentacules et nageoires hachées) et on les a maintenus à −20°C pendant 408 jours. Le texture, mesurée par des méthodes sensorielles, instrumentales et chimiques, a été conservée dans chaque lot pendant tout l'entreposage probablement a cause du faible taux de dénaturation myofibrillaire. On n'a pas décelé de saveur ni d'odeur de rance, malgré une élévation des valeurs d'ATB aprés 284 jours d'entreposage. On n'a pas décelé de mélanose au cours de l'entreposage à l'état congelé ni au cours de la décongélation, mais, si le calmar est maintenu en réfrigération pendant 3 jours après son entreposage à l'état congelé, il apparaît de la mélanose dans tous les échantillons qui n'ont pas été débarrassés de leur peau. La durée d'entreposage de calmar haché, sans addition de conservateurs, est la même que celle du calmar entier.

In order to determine the behavior of trout (Salmo irideus Gibb) muscle in frozen storage, five lots (whole, fillets, and minces obtained by extrusion, “mincer” and “cutter”) were made and stored at -200C for one year. During this period the mince, mainly the one made with “cutter”, was more denaturated than the whole trout and fillets. The highest rate of insolubilization was reached by 255 days of storage (45% of soluble protein in minces and 60% in fillets and whole fish). Also a similar difference was noticed in the cooking drip. The variations of protein solubility do not thoroughly explain the changes in objective texture observed up to 30–75 days of storage. So, other parameters may be connected with these changes. On the other hand, after 165 days, the rancidity increase measured by the TBA value is high, especially in the mince although rancid flavor was detected at 120 days of storage.