Hot Smoked Rainbow Trout Research Articles

Effect of low-dose irradiation on lipid quality and fatty acid composition in vacuum-packed hot smoked trout (Oncorhynchus mykiss) fillets during cold storage

The effects of gamma irradiation at different doses (0, 3 and 5 kGy) on lipid quality and fatty acid composition in vacuum-packed hot smoked rainbow trout (Oncorhynchus mykiss) fillets during cold storage (2 °C) were investigated. The major fatty acids were identified as palmitic, oleic, linoleic and docosahexaenoic acids (DHA). The fatty acid compositions were not affected by the irradiation process initially. However, the increase on the total saturated fatty acids (SFA) of irradiated fillets was higher than the control group at the end of the storage. While a significant decrease was observed in the control group of total polyunsaturated fatty acids (PUFA), no change was observed in the groups irradiated with 3 and 5 kGy doses at the end of the storage. The TBA values of 0, 3 and 5 kGy irradiated groups were 1.27, 1.46 and 1.58 mg MA / kg, respectively, the PV values were 6.12, 9.18 and 9.97 meq / kg and the FFA values were 5.36%, 5.67% and 6.10%, respectively, at the end of the storage. Using a combination of techniques to various processed or fresh seafood products will likely play a significant role in enhancing the manufacture of safe meals with extended shelf lives.

The effect of propolis application on quality properties of vacuum-packed hot smoked rainbow trout (Oncorhynchus Mykiss, Walbaum 1792) fillets during cold storage

This research aimed to apply propolis extract (PE) to extend the shelf life and improve the quality of hot smoked rainbow trout while avoiding apparent changes in organoleptic properties. To this end, the effect of PE at different levels (0,25%, 0,50%, 1%, and 3%) on the physico-chemical, chemical, microbiological, and sensory parameters of vacuum-packed hot smoked rainbow trout (Oncorhynchus mykiss, Walbaum 1792) fillets was investigated throughout cold storage (4 ± 1 °C). The observed shelf life of smoked trout was similar in the control and 0.25% PE groups (56 days). After two weeks (on day 70), the 0.50% and 1% PE groups were spoiled. Finally, on storage day 84, 3% of the PE group was spoiled. The dose of 0.25% PE used in this study was insufficient to show the desired effects on the final product. The application of 3% PE significantly affected the microbiological and chemical properties. However, it had a negative effect on the odor and taste of the products. The 1% PE group demonstrated the most potent sensory properties in color, odor, and overall acceptability. This study shows that 1% PE is useful in hot smoked rainbow trout fillets as a natural antimicrobial and antioxidant.

High Pressure Processing Has Variable Effects on Protein-Related and Sensory Properties of Cold and Hot Smoked Rainbow Trout

High pressure processing (HPP) is a state-of-the-art food preservation method that can be applied to many types of food items, including fish products. HPP has been found to affect fish protein conformation, with potentially positive effects on protein digestibility, but detrimental effects on sensory quality. In this study, cold and hot smoked rainbow trout samples (CSRT and HSRT, respectively) were treated with 200, 400, and 600 MPa at 4 °C for 3 min and tested for solubility of proteins (SP) and water holding capacity (WHC). Level of proteolysis (LP) was tested in an in vitro digestion model. A consumer panel evaluated sensory properties with the Rate-All-That-Apply method. Treatment at 200 MPa positively affected LP in HSRT, while SP and WHC were reduced in CSRT with increasing pressure. HPP also significantly affected texture, appearance, and appeal, especially of CSRT samples. Reduction in SP and WHC contributed to colour changes in CSRT treated with 600 MPa. It was concluded that HPP had more pronounced effects on physicochemical and sensory properties of CSRT than HSRT. The results highlight the importance of optimising the HPP parameters for each product type, in order to minimise the potentially negative effects on protein-related properties and sensory quality.

Preservation status and microbial communities of vacuum-packed hot smoked rainbow trout fillets

Vacuum-packed hot smoked rainbow trout fillets from two different smokehouses of Greece were stored at 2 and 7.9 °C. Microbiological, sensory, and physicochemical changes were monitored. Microbial communities grown on MRS of three different pHs (5.4, 6.4 and 7.4) were also classified and identified using Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Shelf-life was found to differ between products from the two smokehouses (A: 104 and 45 days, B: 100 and 45 days, at 2 and 7.9 °C, respectively). At the time point that sensory rejection was recorded, counts on MRS were found at higher population levels than the other microorganisms tested, almost in all cases. Out of the 567 colonies isolated from MRS of three different pHs, 71 classified as Enterococcus spp., 383 as Candida spp. and 113 as Lactobacillus spp.. Candida zeylanoides dominated exclusively in fillets from the smokehouse A during storage at 2 °C, while Lactobacillus sakei dominated clearly against C. zeylanoides at 7.9 °C, in all pH values. For the smokehouse B, C. zeylanoides or Enterococcus faecalis found to dominate initially in MRS of three pHs, C. zeylanoides, and/or Candida famata in the middle and/or the time point that sensory rejection was recorded at 2 °C, while Lactobacillus curvatus or E. faecalis at 7.9 °C. This study reveals the predominant cultivable spoilage microbiota of vacuum-packed hot smoked rainbow trout, and provides valuable information to the researcher and producers towards the production of more stable products with improved shelf-life.

Influence of Nisin and Lysozyme on the Shelf Life of Hot-smoked Rainbow Trout Fillets (Oncorhynchus mykiss) during Storage at 4 °C

Hot-smoked rainbow trout (Oncorhynchus mykiss) fillets with vacuum packaging are an important export source and the manufacturers recommend a shelf life of 21 d at 4 °C. This time is very short in terms of the shelf life of packaged foods. In this study, nisin and lysozyme (0.5 and 1% w/v, respectively) were used in order to prolong the shelf life of hot-smoked rainbow trout by adding them to the brine (8–10 ˚C, 10 h). Five treatment groups were formed, including the control group. Samples (105) were hot-smoked at 72 ˚C and vacuum-packaged. The effect of nisin and lysozyme (0.5 and 1% w/v) on the chemical [(pH, total volatile basic nitrogen (TVB-N), peroxide, thiobarbituric acid reactive substances (TBARS), free fatty acids (FFAs)], microbiological [total number of aerobic mesophilic bacteria (TMAB), number of lactic acid bacteria (LAB), total number of coliform bacteria (TCB), total number of psychrophilic bacteria (TPB)], and sensorial properties were investigated during storage at 4 °C for 42 d. TVB-N, TBARS, and FFA values were evaluated. The most favorable results among the treatment groups for the chemical analysis were observed in groups treated with nisin (1 and 0.5%, respectively) followed by lysozyme-treated groups (1 and 0.5%, respectively), and the control group. Nisin and lysozyme showed the most important effect microbiologically and extended the shelf life of the samples from 21 d to 42 d at 4-˚C storage. The sensory analyses suggested that nisin and lysozyme treatments did not have a negative impact on the organoleptic properties of samples. Natural antimicrobials (nisin and lysozyme) reduced the TMAB, TCB, and TPB. As a result, it was determined that nisin and lysozyme can be used to increase the quality characteristics and shelf life of hot-smoked rainbow trout fillets instead of synthetic antioxidants and additives.

Storage stability of vacuum-packaged hotsmoked Rainbow trout (Oncorhynchus mykiss) fillets: organoleptic, biochemical and microbiological aspects.

The aim of this research was to investigate some problems related to Rainbow trout's (Oncorhynchus mykiss) hot-smoking process as well as the quality evaluation of the final product. The skin-on and skin-off fillets were hotsmoked and kept in vacuum-packed storage at 2°C±0,1. Organoleptic, biochemical and microbiological analyses were carried out during 120 days of storage. The taste panel assessors were asked to score the smoke intensity, the saltiness, the juiciness and the overall acceptability of the smoked samples. Generally speaking thoughout the study period of organoleptic analyses considerable changes were not observed. The total volatile nitrogen (TVN) content remained lower than 25 mg/Kg smoked fish, till the 120th day of storage. An increase of the malonaldehyde content up to 2,0 mg/Kg was noted at the 120th day of storage. At the same time the nitrite content was decreased from 34 ppm to 10 ppm. The microbiological examinations showed that the total viable count, the phsychrotrophs and lactic acid bacteria gradually exhibited a significant increase at the end of the 120th day of storage.

Storage stability of vacuum-packaged hotsmoked Rainbow trout (Oncorhynchus mykiss) fillets: color and texture aspects

The aim of this research was to investigate some problems related to Rainbow trout's (Oncorhynchus mykiss) hot-smoking process as well as the color texture evaluation of the final product. The skin-on and skin-off fillets were hot-smoked and kept in vacuum-packed storage at 2°C±0.1. Color and texture measurements and biochemical analysis were carried out during 120 days of storage on days 1, 45, 75 and 120. The results have showed no significant differences between skin-on and ski-off fillets in carotenoids and retinol content. This values were reduced from 0,4-0,5 and 0,08-0,10 mg/g (1st day) to 0,2 and 0,04 mg/g by day 45 respectively. Thereafter they remained unchanged until the end of the storage. However, they were proved sufficient for the stability of the red color of the final product, as the a* value remained fairly constant, during the whole storage period. Significant differences between skin-on and skin-off fillets were observed in their external surface color. Both L* and a* values were lower in skin-off fillets and this is probably attributed to the more intense dehydration and absorption of the smoke constituents in this fillets. Moreover, the filleting of raw material before processing, resulted in both complete absence of fish gapping in the end product and satisfactory texture, which remained the same during the whole storage period.

Effects on quality properties of smoked rainbow trout (Oncorhynchus mykiss) fillets of chitosan films enriched with essential oils

In this study, it has been aimed to determine the effects of coating chitosan films enriched with thyme (Origanum minutiflorum) and rosemary (Rosmarinus officinalis) essential oil (0.2% added) on some quality properties of hot smoked rainbow trout (Oncorhynchus mykiss) during storage at 4 ± 1C. Sample groups were created as control group that hot smoked fillets (Kf), hot smoked and coated with chitosan film fillets (Kt), hot smoked and coated with chitosan film enriched by rosemary essential oil fillets (By), and hot smoked and coated with chitosan film enriched by thyme essential oil fillets (Kk). Sensory, chemical and microbiological analysis and moisture measurements were made during the storage periodically. In the sample groups were determined as inconsumable for Kf and Kt on 42nd day, for By on 49th day and for Kk on 63rd day. According to result of the study, it has been thought that coating with chitosan enriched essential oils are effects on appreciated by consumer and increasing of shelf life. Practical Applications Different processing technologies are used to protect valuable but perishable foods especially such as fish. Today to be added essential oils into the foods will supply product variety and increasing shelf life for demand of prepared food. This study will be a database of the fish processing technology.

Combine Effects of Essential Oils and Packaging on Smoked Rainbow Trout Stored 4°C

In this study, the effect of essential oils (thyme and clove) and packaging treatments (vacuum and modified atmosphere) on the storage of hot smoked rainbow trout (Oncorhynchus mykiss) fillets over a period of 120 days at 4°C was investigated. Fillets were subjected to microbiological (total aerobic mesophilic bacteria, psychrotrophic bacteria, lactic acid bacteria, yeast and mould), chemical analyses (pH, thiobarbituric acid reactive substances and total volatile base nitrogen) and quality testing throughout the storage period. Difference in microbiological and chemical changes between samples was found to be significant (p < 0.05) during storage period. Sensory evaluation showed significant differences between the samples, and V2 and M2 samples were assessed as the most acceptable products by the panellists. In conclusion, essential oils treatment to hot smoking had a positive effect on shelf life of rainbow trout, especially clove oil showed more positive effect when compared with thyme oil. Copyright © 2015 John Wiley & Sons, Ltd.

Utilisation of antimicrobial agents at pre- and post-smoking on the microbial quality of hot-smoked rainbow trout(Oncorhynchus mykiss)fillets

Utilisation of antimicrobial agents at pre- or post-smoking processes was considered for the microbial quality of hot-smoked trout fillets prepared at plant scale. Potassium sorbate (PS) and sodium lactate (SL) were used separately or in combinations at 3% (w/v) in brine for pre-smoking or with spraying at post-smoking. Pre-smoking usage could reduce the total aerobic mesophilic bacteria (TAMB) values better than the post-smoking usage during storage. However, post-smoking application was more effective at preventing the moulds and yeasts (MY) growth. PS in brine at pre-smoking was most efficient, which could keep trout fillets for even four weeks at 6±1°C storage within the range of consumable limits. Additionally, PS usage reduced the contaminated bacterial diversity and especially eliminated the outgrowth of Serratia liquefaciens. As a conclusion, pre-smoking application repressed the contaminated microbial growth during the storage of smoked trout fillets, which may eliminate the microbial risks.

Effect of Essential Oils and Packaging on Hot Smoked Rainbow Trout during Storage

This study investigated the effect of essential oils (EOs) (thyme and rosemary) and packaging (vacuum and modified atmosphere – 50% CO2/+50% N2) on hot smoking rainbow trout during storage (4C) for 90 days. Fillets were conducted to microbiological (i.e., total aerobic mesophilic bacteria, psychrotrophic bacteria, lactic acid bacteria, Clostridium perfringens, C. botulinum, yeast and mold) and chemical (i.e., pH, thiobarbituric acid reactive substances, total volatile base nitrogen) analyses and sensory quality on 0, 10, 20, 30, 40, 50, 60, 70, 80 and 90 days. In conclusion, EO treatment to smoking showed positive effect on shelf life, especially thyme oil showed more positive effect when compared with rosemary oil. Practical Applications Smoking is one of the oldest methods used for preserving fresh fish and other seafood products. The use of an essential oil in fresh fish preservation may be considered an alternative “natural” additive, extending the shelf life of the product. Our study has clearly shown that addition of rosemary and thyme extract in smoked fish resulted in longer shelf life, and this method could be commercially used.

Effect of different packaging methods on shelf life of hot smoked rainbow trout (Oncorhynchus mykiss) during storage at 0-2ºC

This study was carried out to investigate the effects of three different packing methods including modified atmosphere, vacuum and common packaging on chemical, microbial and sensorial quality and shelf life of hot smoked Rainbow trout (Oncorhynchus mykiss) during storage at refrigerated temperature. For hot smoking, rainbow trout were gutted and cut in butterfly form and washed. Fish gutted brining with 15% salt for 4 h and they were hot smoked by using Atmoos smoking cooking room. Then hot smoked samples were packed in modified atmosphere (with gas ratio of, N2:50%, O2:5%, CO2:45%), vacuum and common packaging and stored at refrigerated temperature (0-2 o C). Chemical values (total volatile basic nitrogen, moisture, peroxide, pH), microbial values (total microbial count, mold and yeast) and sensorial index (aroma, flavor, color and texture) were determined on 0, 10, 20, 30 and 40 days of storage. The results showed that samples did not have a significant difference in moisture and pH values (p>0.05), however significant different was found in peroxide, total count, mold and yeast and TVB-N values (p<0.05).Also, results of sensory evaluation have been showed that the score of color, flavor, texture and aroma in modified atmosphere packaging were more than other treatments (p<0.05). The Shelf life of the hot smoked trout is specified between 20 to 30 days, 30 to 40 days and at least 40 days in common, vacuum and MAP packaging, respectively. So, using the modified atmosphere for hot smoked trout can enhance quality and increase the shelf life of trout in refrigerated storage condition up to 40 days.

Effect of combined application of plant extract and vacuum packaged treatment on the quality of hot smoked rainbow trout

The effect of plant extract (bay leaf, rosemary, black cumin seed and lemon oil) treatment on the shelf life of vacuum-packaged fish was studied. Hot smoked rainbow trout was treated with 1 % plant extracts, and their shelf lives were compared with those of control (only vacuum packaged) samples. Samples were stored at 2 °C and sensory evaluation as well as chemical and microbiological analyses were conducted weekly. The control group was spoiled after four weeks of storage. In contrast the addition of plant extracts decreased microbiological activity. The results obtained from this study showed that the shelf life of hot smoked trout stored in cold storage (+2 °C), as determined by overall acceptability of all data, was 6 weeks for rosemary, black cumin seed, and lemon oil treatment plus vacuum packaged fish and 7 weeks for bay leaf oil treatment plus vacuum packaged smoked fish.

The Effect of Thyme and Garlic Oil on the Preservation of Vacuum-Packaged Hot Smoked Rainbow Trout (Oncorhynchus mykiss)

Quality and shelf life of filleted hot smoked rainbow trout packaged in vacuum packaging (untreated) and with thyme oil (TO), and garlic oil (GO)-treated, after vacuum-packaged (VP) conditions stored at 2 °C, were investigated by measurement of microbiological, sensory and physicochemical analyses. Acceptability scores for appearance, odour, taste and texture of untreated and treated smoked trout decreased with storage time. The limit of sensory acceptance was reached after 5 weeks for the untreated samples, after 7 weeks for with thyme oil-treated samples (TO + VP) and after 6 weeks for with garlic oil-treated (GO + VP) samples. Total viable count evaluated that thyme oil- and garlic oil-treated vacuum-packaged samples had good results up to 7 weeks compared with 5 weeks in control vacuum packs. Psychrotrophic counts for untreated and treated samples exceeded 6 log cfu/g after 5 and 6 weeks of cold storage, respectively. Treated samples presented the lowest lactic acid bacteria counts. Total volatile basic nitrogen and trimethylamine nitrogen values gave acceptable results for up to 5 weeks for the untreated samples, 7 weeks for thyme- and garlic oil-treated samples. Treated with thyme oil samples presented the lowest thiobarbituric acid index values. The results obtained from this study showed that the shelf life of hot smoked rainbow trout stored in cold storage (2 °C), as determined by overall acceptability of all data, is 5 weeks for vacuum-packaged samples and 7 weeks for thyme- and garlic oil-treated vacuum-packaged smoked fish.

Determination of Total Serum Protein Levels Fed by Hot Smoked Rainbow Trout (Oncorhynchus mykiss) Diets in Rats

Determination of Total Serum Protein Levels Fed by Hot Smoked Rainbow Trout (Oncorhynchus mykiss) Diets in Rats

Effect of Different Packaging Methods and Storage Temperatures on the Growth of Listeria monocytogenes in Raw and Hot Smoked Rainbow Trout (Oncorhynchus mykiss)

ABSTRACT The effect of packaging methods on the growth of Listeria monocytogenes (ATCC 19114, 7644, 19113) at 3°C and 7°C in fresh and hot smoked trout (Onchorynchus mykiss) were monitored for 30 d. Samples were packaged under an air, nitrogen, vacuum, or nitrogen gas flush with vacuum atmosphere. The strains of L. monocytogenes tested did not grow in raw trout at 3°C, but grew at 7°C from log 2 to 4 cfu/g after 10 days storage. The number of spoilage microbes increased substantially during storage at 7°C, causing changes in aroma that make the product unacceptable after 5 to 10 days. L. monocytogenes did not grow on hot smoked trout at 3°C, but increased to log 7 cfu/g at 7°C during storage. Aerobic microflora grew slowly at 3 and 7°C in the smoked trout, and sensory quality remained within an acceptable range under both temperature conditions. Because of the sensory changes associated with decomposition, consumers would most likely consider MAP packaged fresh trout, but not necessarily smoked trout, held at 7°C to be spoiled before L. monocytogenes levels would become high enough (e.g., 1,000 cfu/g or higher) to pose a food safety risk.

Comparison of the shelf lifes of map and vacuum packaged hot smoked rainbow trout (Onchoryncus mykiss)

The objective of this study was to determine the differences of microbiological and chemical quality in MAP and VP packages in refrigerated smoked trout fillets. Such information is important in evaluating the safety of these products. Three groups were constituted: group A – packed in 60%Co2/40% N2; group B – packed in 50%CO2/50% N2 and group C– vacuum packed. The ratio of fillet to package volume was 1/3 chemical analysis and microbiological analysis were done and also instrumental and sensory analysis were used to determined the shelf life. The observed shelf life of smoked trout was found at least 33 days in vacuum package, 47 days in 60% CO2/40% N2 gas mixture and 40 days in 50% CO2/50% N2 gas mixture according to results of microbiological analysis. The observed shelf life of smoked trout in MAP group A was determined as 14 days more than VP packs according to results of microbiological and sensory analysis in the study.

Effect of Hot-Smoked Rainbow Trout (Oncorhynchus mykiss) Diets on the Protein Levels of Liver Tissue in Rats

Aims: Free radicals may not only affect the denatured cell structure but also reduce protein levels. These mechanisms are critical and need to be clarified as a high priority. Because of the limited information on this subject, in this respect, the effects on protein levels of liver tissue in rats fed hot-smoked rainbow trout (Oncorhynchus mykiss) were investigated. Methods:Four diets containing fresh and hot-smoked rainbow trout flesh and vitamins were prepared and commercial pellet food was purchased. Four groups of female Wistar rats were fed the diets for 28 days. The rats were killed by decapitation, and the hepatic tissue was removed. Total protein and detection of protein bands using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were evaluated. Results:The liver protein level in rats fed a hot-smoked rainbow trout flesh + vitamin diet was increased significantly compared with the other diet groups (p < 0.001, p < 0.009 and p < 0.011). 10 protein bands were visualized on rat gels. The molecular weights of protein bands detected were 200, 130, 70, 50, 42, 38, 26, 25, 24 and 14 kDa, respectively. The 25-kDa band of group V had a dense appearance. Also, the 14-kDa band appeared as very dense in groups V, B and K, but this band did not have a dense appearance in group D. Conclusion:Nourishment with smoked fish diets containing antioxidant substances reduced the harmful effects of free radicals and positive effects were observed on protein metabolism.

Comparison of the Baird-Parker Agar and 3M Petrifilm Staph Express Count Plate Methods for Enumeration of Staphylococcus aureus in Naturally and Artificially Contaminated Foods

The recently developed 3M Petrifilm Staph Express Count plate (PFSE) method was compared with the U.S. Food and Drug Administration Bacteriological Analytical Manual's Baird-Parker agar spread plate (B-P) method for enumeration of Staphylococcus aureus in naturally contaminated, mechanically separated poultry (MSP; n = 92) and raw milk (n = 12). In addition, mozzarella and Parmesan cheeses and hot-smoked rainbow trout and chub were surface inoculated with a three-strain mixture of S. aureus, stored at 5°C, and periodically analyzed with both methods for numbers of S. aureus. For naturally contaminated raw milk and MSP samples, the PFSE method yielded counts that were not significantly different (P > 0.05) from counts obtained using the B-P method. From raw milk and MSP samples, 60% (21 of 35) and 55% (124 of 226), respectively, of confirmed (DNAse-positive) isolates from PFSE plates were identified by further testing as S. aureus. Corresponding S. aureus identification rates for isolates forming typical colonies on B-P plates were 53% (19 of 36) and 50% (125 of 248). For both methods, other staphylococci composed the vast majority of tested isolates that were not identified as S. aureus. For inoculated hot-smoked fish, S. aureus counts from the PFSE method were not significantly different from counts from the B-P method. Compared to the B-P method, significantly lower numbers of inoculated S. aureus were recovered using the PFSE method in analyses of mozzarella cheese stored 28 and 42 days at 4°C. The PFSE and B-P methods were not significantly different for inoculated cheeses at all other sampling times. DNAse-positive isolates from PFSE analyses of inoculated cheeses and smoked fish were identified as S. aureus 98% (51 of 52) and 86% (36 of 42) of the time, respectively, as compared with 100% (58 of 58) and 95% (40 of 42) of the time for typical B-P isolates. Overall, the PFSE and B-P methods appeared to perform similarly in enumeration of S. aureus in animal-derived foods.

EFFECT OF FILMS OF DIFFERENT OXYGEN TRANSMISSION RATE ON TOXIN PRODUCTION BY CLOSTRIDIUM BOTULINUM TYPE E IN VACUUM PACKAGED COLD AND HOT SMOKED TROUT FILLETS

ABSTRACT Studies were done to determine the effect of film oxygen transmission rate (OTR) on the time to toxicity in vacuum packaged cold and hot smoked rainbow trout fillets challenged with C. botulinum type E (102 spores/g) and stored at refrigerated conditions (4C), and under mild (8C) and moderate (12C) temperature abuse conditions. While no samples were toxic at 4C, toxin was detected within 28 days at 8C for cold smoked trout fillets vacuum packaged in films with high OTR. Toxin was also detected for most vacuum packaged hot smoked trout fillets within 14–28 days at 8C, with the exception of trout fillets packaged in films with an OTR &gt; 10,000 cc/m2/day. In most cases at 8C, spoilage, based on odor/color scores, preceded or occurred simultaneously with toxigenesis. At 12C all cold and hot smoked trout were toxic after 14–21 days and samples packaged in films with an OTR &lt;5000 cc/m2/day became toxic before, or at the same time as, samples became spoiled. This study has shown that vacuum packaging of trout fillets in low gas barrier films, ranging in OTR from approximately 3,000 to approximately 10,000 cc/m2/day at 24C and 0% relative humidity (RH), did not prevent the growth and toxin production by C. botulinum in vacuum packaged cold and hot smoked trout fillets at 12C. Additional barriers, other than the OTR of the packaging film, need to be considered to ensure the safety of vacuum packaged trout fillets, particularly at mild to moderate temperature abuse storage conditions.