scholarly journals Monitoring the Freshness of Rainbow Trout Using Intelligent PH-sensitive Indicator During Storage

2019 ◽  
Author(s):  
Fatemeh Rastiani ◽  
Ali Jebali ◽  
Seyed Hossein Hekmatimoghaddam ◽  
Elham Khalili Sadrabad ◽  
Fateme Akrami Mohajeri ◽  
...  
Keyword(s):  
Rainbow Trout ◽  
Unsaturated Fatty Acids ◽  
Viable Count ◽  
Bromocresol Green ◽  
Oxidation Reactions ◽  
Total Volatile ◽  
Ph Indicator ◽  
Expiry Date ◽  
Total Volatile Basic Nitrogen ◽  
Basic Nitrogen

Background: The rainbow trout fish is susceptible to spoilage due to its high content of unsaturated fatty acids. It should be kept at low temperature to reduce microbial, enzymatic, and oxidation reactions. The purpose of this study was to design a packaging that contains a pH indicator for monitoring freshness of the rainbow trout fish during storage at refrigerator. Methods: The indicator contained agarose as the carrier, bromocresol green as pH indicator, and silica as surface provider. It was covered by polypropylene film and attached inside the package. Freshness of the trout stored in the refrigerator was assessed by chemical (total volatile basic nitrogen and pH) and microbiological (total viable count) methods. Results: The pH of fish gradually decreased after the third day since color of the indicator changed from yellow to green on day 3 and then to blue on day 6. The indicator's response was correlated with changes in the microbial population and also with levels of total volatile basic nitrogen and pH. The results showed that the designed indicator was sensitive to different pH levels and could be applied as part of the intelligent packaging system. Conclusion: The freshness indicator worked well before the expiry date of fish, which makes it suitable for food quality assessment. So, this indicator can be used for real-time monitoring of packaged fish freshness.

scholarly journals Effects of Vacuum and Modified Atmosphere Packaging on the Quality and Shelf-Life of Gray Triggerfish (Balistes capriscus) Fillets

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 250
Author(s):  
Eduardo Esteves ◽  
Luís Guerra ◽  
Jaime Aníbal
Keyword(s):  
Shelf Life ◽  
Modified Atmosphere Packaging ◽  
Viable Count ◽  
Modified Atmosphere ◽  
Total Viable Count ◽  
Total Volatile ◽  
Total Volatile Basic Nitrogen ◽  
Basic Nitrogen ◽  
Balistes Capriscus ◽  
Gray Triggerfish

Seafood products are perceived as healthy foods. However, several species of seafood are still not fully utilized for different reasons or can be valued outside the original locale, if issues with the short shelf-life and/or the preparation/presentation form are overcome, e.g., gray triggerfish, Balistes capriscus. Consumed mostly fresh, its flesh is of excellent quality. We studied the effect of different types of packaging (in air (AIR), vacuum (VP), and modified atmosphere (MAP)) on physicochemical (color and texture, pH, and total volatile basic nitrogen), microbiological (total viable count, psychrotrophic, sulphide-reducing bacteria, and acid-lactic bacteria), and sensory qualities, and shelf-life of gray triggerfish fillets stored at refrigeration temperature for 15 days. The samples were analyzed on days 0 (fresh fish), 5, 10 (8 and 12 for sensory analysis), and 15 after filleting and packaging. During the trial, fillets became lighter (increased L*) and yellower (b* >> 0) with time of storage. Distinct patterns were observed for pH among treatments. Unexpectedly, the increasing trend observed in the texturometer-derived hardness of VP and MAP fillets, contrasted with the sensory assessment, wherein panelists perceived a clear softening of fillets. VP delayed and MAP inhibited the increase in TVB-N contents of fillets compared to fillets packed in AIR. Total viable count and psychrothropic bacteria of fillets in AIR exceeded the conventional limit of 7 log(CFU/g) on day 10, while in fillets packed in VP and MAP, their abundance remained below that limit during the trial. The organoleptic attributes of fillets perceived by a sensory panel changed significantly in all treatments during the storage trial. Willingness to consume the fillets decreased constantly in AIR and MAP, but not in VP fillets. Considering primarily sensory, but also biochemical and microbiological parameters, namely panelists’ rejection, total volatile basic nitrogen content, and total viable count and psychrotrophic bacteria abundance, the shelf-life of fillets packed in air was eight days. Vacuum and modified atmosphere packaging extended the shelf-life to 15 and 12 days, and thus can add value to this product. Future research regarding the VP and MAP of gray triggerfish fillets could involve the optimization of mixtures of gases use and/or the application of combined processes.

scholarly journals The effect of vacuum packaging on physicochemical changes in rainbow trout (Oncorhynchus mykiss) during cold storage

2014 ◽  
Vol 83 (10) ◽  
pp. S51-S58 ◽  
Author(s):  
František Ježek ◽  
Hana Buchtová
Keyword(s):  
Fatty Acids ◽  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Shelf Life ◽  
Thiobarbituric Acid ◽  
Acid Value ◽  
Total Volatile ◽  
Total Volatile Basic Nitrogen ◽  
Basic Nitrogen ◽  
Thiobarbituric Acid Value

The aim of the study was to monitor changes in selected physical (awwater activity, pH values) and chemical (TVBN total volatile basic nitrogen, TMA-N trimethylamine nitrogen, FFA free fatty acids, PV peroxide values, TBA thiobarbituric acid value) properties in the shelf life of rainbow trout (Oncorhynchus mykiss) muscle. A total of 192 trout were examined. Control samples (96 samples) were simply packaged in contact with atmospheric oxygen, while experimental samples (96 samples) were packaged in a commercial vacuum (98%). All the samples were stored at 2 ± 2° C for 11 days. Analyses were performed on storage days 1, 2, 4, 7, 9, and 11. During the experiment, aw values increased in both types of packaging (in air: 0.982; vacuum-packaged: 0.989). At the end of storage, TVBN and TMA concentrations were at 28.88 ± 4.42 and 19.28 ± 3.00 g mg·100-1, respectively, in the muscle of vacuum-packaged trout; and at 30.52 ± 2.91 and 19.94 ± 2.05 mg·100 g-1, respectively, in fish in simple packaging. The FFA content in vacuum-packaged fish initially declined before increasing to 3.67 ± 2.37% of total fat as oleic acid later in the experiment. The pattern of PV changes was inconclusive, and significant changes (P < 0.01) were observed in both types of packaging. On monitoring day 11, TBA values had ​​increased to 7.34 ± 3.10 mg·kg-1 in vacuum-packaged fish and to 26.03 ± 8.00 mg·kg-1 in fish in simple packaging. Free fatty acids are not a good indicator of spoilage because they are converted to hydroperoxides. Vacuum packaging effectively slowed down oxidative changes in rainbow trout muscle. The peroxide content is not a suitable indicator of shelf life as peroxides are decomposed to secondary products. Total volatile basic nitrogen and thiobarbituric acid value can be recommended as suitable indicators of freshness and shelf life.

scholarly journals Detection of Mackerel Fish Spoilage with a Gas Sensor Based on One Single SnO2 Nanowire

Chemosensors ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 2
Author(s):  
Matteo Tonezzer
Keyword(s):  
Bacterial Population ◽  
Viable Count ◽  
Sensor Response ◽  
Microbial Count ◽  
Total Volatile ◽  
Double Blind ◽  
Total Volatile Basic Nitrogen ◽  
Non Invasive ◽  
Basic Nitrogen ◽  
Different Temperatures

A chemosensor consisting of one single tin oxide nanowire is used to determine the freshness status of mackerel fish (Scomber scombrus) in a quick and non-invasive way. The tiny chemoresistive sensor is first tested with pure ammonia and then used to measure the total volatile basic nitrogen from different samples of fish at different degrees of freshness. The sensor has proved capable of determining the freshness of a sample in few seconds compared to traditional methods such as microbial count and chromatography, which take hours. The sensor response is well correlated with the total viable count (TVC), proving that the total volatile basic nitrogen is a good way to quickly test the bacterial population in the sample. After calibrating the sensor (following the degradation of the fish during almost two days), it has been tested with random double blind samples, proving that it can well discriminate the degree of freshness of the fish preserved at different temperatures.

Total volatile basic nitrogen (TVB-N) and its role in meat spoilage: A review

2021 ◽  
Vol 109 ◽  
pp. 280-302
Author(s):  
Alaa El-Din A. Bekhit ◽  
Benjamin W.B. Holman ◽  
Stephen G. Giteru ◽  
David L. Hopkins
Keyword(s):  
Total Volatile ◽  
Total Volatile Basic Nitrogen ◽  
Meat Spoilage ◽  
Basic Nitrogen

Total Volatile Basic Nitrogen and other Physico-chemical and Microbiological Characteristics as Related to Ripening of Salted Anchovies

1999 ◽  
Vol 64 (2) ◽  
pp. 344-347 ◽  
Author(s):  
M. M. Hernandez-Herrero ◽  
A. X. Roig-Sagues ◽  
E. I. Lopez-Sabater; ◽  
J. J. Rodriguez-Jerez ◽  
M. T. Mora-Ventura
Keyword(s):  
Total Volatile ◽  
Total Volatile Basic Nitrogen ◽  
Basic Nitrogen ◽  
Microbiological Characteristics ◽  
Physico Chemical

Hygienic Quality and Shelf Life of a Moroccan Cooked (Kosher) Sausage

1995 ◽  
Vol 58 (2) ◽  
pp. 182-185 ◽  
Author(s):  
AHMED DAOUDI ◽  
FRANK A. STOLLE ◽  
ABDELHAMID BELEMLIH ◽  
HENRI R. ZAMBOU ◽  
HARTMUT G. EISGRUBER
Keyword(s):  
Ambient Temperature ◽  
Shelf Life ◽  
Water Activity ◽  
Total Volatile ◽  
Total Volatile Basic Nitrogen ◽  
Basic Nitrogen ◽  
Sensory Changes ◽  
Quality And Shelf Life ◽  
Microbial Status

Sensory, physicochemical and microbiological changes in Moroccan cooked kosher sausages stored at 6°C and 25°C were monitored over 35 days. Kosher sausages were very prone to changes in microbial status, as a result of high pH and water activity-values (aw-values) after processing. After 3 days of storage at 25°C and 1 week at 6°C the microbial colonies increased distinctively. Sensory changes were only detectable after the seventh day at 25°C. At 6°C, these sausages kept their sensorial characteristics. Levels of total volatile basic nitrogen were lower in the kosher sausages at 6°C than in those kept at 25°C. Changes at 25°C affected the quality of kosher sausage and limited the shelf life. From these results it can be concluded that storage at 25°C (ambient temperature) for 3 days or at 6°C (chilling) for 7 days without sensory changes is possible.

scholarly journals Gymnorhynchus gigas in Lepidopus caudatus (Actinopterygii: Perciformes: Trichiuridae): prevalence and related effects on fish quality

2014 ◽  
Vol 32 (No. 4) ◽  
pp. 320-325 ◽  
Author(s):  
F. Giarratana ◽  
D. Muscolino ◽  
Ch. Beninati ◽  
G. Ziino ◽  
A. Giuffrida ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Total Volatile ◽  
Fish Quality ◽  
Total Volatile Basic Nitrogen ◽  
Basic Nitrogen ◽  
Hygienic Quality ◽  
High Prevalence ◽  
The Mediterranean

We evaluated the effects of Gymnorhynchus gigas on the freshness and hygienic quality of Lepidopus caudatus. Total Volatile Basic Nitrogen (TVB-N), Trimethylamine Nitrogen (TMA-N), as well as Specific Spoilage Organisms (SSOs) are the most important freshness indicators in fish. Our study was carried-out on 65&nbsp;specimens of L. caudatus kept in ice and stored at 2&deg;C for different period of time. The microbiological charge of SSOs recovered on a portion of parasitised muscles (MP) was compared with those recovered on portions of parasite-free muscles (M). The contents of TVB-N and TMA-N on MP, M, and G. gigas larva/ae were measured using the Conway microdiffusion method. High prevalence (72.31%) of G. gigas in the specimens of L. caudatus from the Mediterranean sea was observed. No statistically significant differences (P &lt; 0.05) between M and MP were found during storage. However, massive infestation of G. gigas on the muscle of the silver scabbardfish could negatively influence TVB-N values, without compromising the sensorial characteristic of fish.

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