Total Volatile Base Research Articles

Assessment of Spoilage Microbiota of Rainbow Trout (Oncorhynchus mykiss) during Storage by 16S rDNA Sequencing

Due to the high contents of protein and fat in rainbow trout, it is highly susceptible to spoilage, which limits the storage and transportation processes. Exploring the spoilage microbial community during rainbow trout storage is essential to develop an effective preservation method. Here, the changes in the total bacterial colony and total volatile base nitrogen (TVB-N) during the storage of rainbow trout were investigated. Storage at 0 °C can effectively slow down the spoilage process with bacterial counts and TVB-N contents decreased from 8.7 log CFU/g and 18.7 mg/100 g obtained at 4 °C to 5.6 log CFU/g and 14.5 mg/100 g, respectively. 16S rDNA high-throughput sequencing results showed that the diversity of microbial genera decreased during storage. Acinetobacter, Pseudomonas, and Shewanells gradually became the dominant spoilage genera with contents of 59.9%, 18.6%, and 1.7%, respectively, in the late stage of storage. The spoilage abilities of bacteria belonging to the Pseudomonas and Shewanells genera were analyzed. Shewanella sp. S5-52 showed the highest level of TVB-N content (100.6 mg/100 g) in sterile fish juice, indicating that it had a strong spoilage ability. This study confirmed the dominant spoilage bacterial genera and evaluated the spoilage abilities of isolated strains during the storage of rainbow trout, which laid the foundation for further investigation of the spoilage mechanism of rainbow trout and other aquatic products.

Changes in physicochemical properties of silver carp (Hypophthalmichthys molitrix) surimi during chilled storage: The roles of spoilage bacteria

Chilled surimi has become increasingly popular owing to its superior texture and freshness. In this study, changes in the microbiota and gel properties during chilled surimi storage, and the contributions of dominant bacteria to the physicochemical properties of chilled surimi were investigated. The results showed that Pseudomonas gessardii, Aeromonas media, and Acinetobacter johnsonii were the dominant bacteria during chilled surimi storage. P. gessardii was the key bacteria that degraded protein in the process of surimi spoilage, which led to high total volatile base nitrogen (TVB-N), trichloroacetic acid (TCA)-soluble peptides as well as poor gel properties. Both P. gessardii and A. media were high putrescine producers, whereas only A. media produced cadaverine. In this study, spoilage microorganisms in chilled surimi were investigated for the first time, and it was found that P. gessardii had the greatest influence on surimi quality, which provides a research basis for in-depth study on the mechanism of microbial spoilage and the preservation of chilled surimi.

Quality of frozen mackerel during storage as processed by different freezing methods

ABSTRACT The fresh mackerel was frozen using four different quick-freezing methods, such as refrigerator freezing, quick freezer freezing, spiral tunnel freezing and plate freezing. Water retention, color, texture, electrical conductivity, total volatile base nitrogen (TVB-N), K value, malondialdehyde (MDA), sulfhydryl group and protein secondary structure were used as physicochemical indicators to evaluate the changes in fish quality, and water migration in the fish was observed by low field NMR. The results showed that the mackerel treated with spiral tunnel freezing method was the closest to the fresh samples, with the best water retention capacity during freezing, slow decrease in hardness and elasticity, low rate of increase in conductivity values, TVB-N content, MDA content and K value, slow decrease in total sulfhydryl content, and more stable protein secondary structure. This indicated that fat oxidation was the lowest and protein degradation was the least, which effectively maintained the moisture and freshness of the samples and was the most favorable treatment to maintain the quality of mackerel compared with other groups.

Isolation of Protease-Producing Bacteria from Shrimp Paste and the Characteristics of Fermenting Catfish Paste

ABSTRACT In this study, six protease-producing halophilic bacterias were isolated from traditional shrimp paste. These strains were used as mixed starter culture to ferment minced catfish muscle. The pH and total volatile base nitrogen in the group with mixed starter cultures (ZB) was lower than that of the group without starter (ZA). The total acidity and the content of amino acid nitrogen and free amino acid in ZB was higher. Additionally, the ZB exhibited a strong umami and fermented flavor. The results show that protease-producing bacteria could improve the flavor and nutritive value of fermented Chinese long-snout catfish by-products.

Effects of cuminaldehyde on toxins production of Staphylococcus aureus and its application in sauced beef

The inhibitory mechanism of CUM on Staphylococcus aureus exotoxins and invasive enzyme, and the effect of CUM on sauced beef were investigated. Treatment with sub-minimum inhibitory concentrations of CUM observed very little decrease in cell density after 24 h. Additionally, CUM reduced hemolytic activity by inhibiting the formation of heptamer, and inhibited the content of enterotoxin in culture medium and sauced beef. The transcription of genes encoding α-hemolysin, staphylococcal enterotoxin A and Panton-Valentine leukocidin were down-regulated after treatment with CUM. Compared with the control group, the addition of CUM caused a significant decrease in S. aureus counts, total volatile base nitrogen, acid value, and thiobarbituric acid reactive substances of sauced beef after 9 d. Furthermore, CUM improved the redness (a*) of sauced beef. These results confirmed that CUM could effectively restrain the synthesis of S. aureus toxin, and the addition of CUM to sauced beef was the potential way to inhibit the growth of food pathogens and maintain quality profiles.

Application of Edible Coating of Durian Seed Starch Chitosan Composites With Kesum Leaves Extracts on Microbiological Quality And TVB-N of Beef Sausage

The edible coating is one alternative that has the potential to extend the shelf life of sausages. This study aimed to determine the effect of the type of packaging and the storage times of beef sausages at frozen storage. The study using the factorial completely randomized design (CRD) with two factors. The first factor is the type of packaging (K1: edible coating durian seeds starch-chitosan; K2: edible coating durian seeds starch-chitosan with kesum leave extract; K3: plastic LDPE). The second factor is storage time (L0: 0 months; L1: 1 month; L2: 2 months; L3: 3 months; L4: 4 months) with four replication. The research variable observed was the sausage quality like TPC (Total Plate Count) and TVB-N (Total Volatile Bases). The result showed that the treatment of type packaging, storage time, and the interaction had a very significant effect on TPC with the lowest value K3L0 (2.31 x 104 CFU/g) and the highest value K1L4 (11.79 x 104 CFU/g). And, it had a significant effect on TVB-N with the lowest K1L0 (9.19 mg/N/100 g) and the highest value K1L4 (50.93 mg/N/100 g). Edible coating of durian-chitosan seed starch with kesum leaf extract can extend the shelf life of beef sausage for four months at freezing temperature based on the TPC value of 9.65.104 cfu/g and TVB-N value 23.96 mg N/100 g.

Effects of cold treatments on lipidomics profiles of large yellow croaker (Larimichthys crocea) fillets by UPLC-Q-Exactive Orbitrap MS analysis

Cold treatment offers an effective avenue to preserve large yellow croaker fillets. However, the lipid distribution of fillets is unclear after cold treatments. This study aimed to identify differences of lipids among the fresh (RAW) and two cold treatments (− 1 ℃ and − 3 ℃) of large yellow croaker fillets using a lipidomics approach. A total of 2317 lipid species in RAW and two cold treatments were recognized and assigned to 13 sub-classes of lipids by using ultra-high-performance liquid chromatography-Q-exactive orbitrap mass spectrometry (UPLC-Q-Exactive Orbitrap MS) and lipidsearch software approach. Furthermore, there are 54 significantly different lipids were selected as potential lipid candidates of lipid oxidation of fillets by using correlation analysis between all individual lipids variables and freshness indicators (color, pH, thiobarbituric acid reactive substances, and total volatile bases nitrogen). All these potential candidates had involved 6 metabolic pathways that found the significant metabolic process on lipid oxidation after cold treatments. The autophagy-animal and glycerophospholipid metabolism were found to be two important pathways to analyze the lipids change, and were used to find the significant potential candidates of lipid oxidation on cold treatment. This work could provide a novel insight on the lipid changes analysis of large yellow croaker fillets after cold treatments.

Effect of vacuum packaging on the shelf‐life of shrimp analog prepared from Pangasionodon hypophthalmus surimi during refrigerated storage

The present research aimed at investigating the quality characteristics of ready to cook shrimp analog prepared from Pangasionodon hypophthalmus alkaline-saline washed surimi under vacuum packaging (VP) conditions at refrigerated temperature (3 ± 1°C). The normal packaging was used as a control (C). During the storage period, the pH of the C samples correlated positively with total volatile base nitrogen and peroxide value. The results demonstrated that VP (24.65 mg N %) significantly (p < .05) delayed total volatile base nitrogen in comparison with the C (19.39 mg N %) at the end of 21 days of storage. The psychrophilic microorganisms were detected from the 9th (C) and 12th (VP) day onward. The obtained data were subjected to principal component analysis and the total variance explained by the two factors for the shrimp analogs stored for different days was 86.8%. The results indicated that VP shrimp analogs had a better shelf-life when stored at 3 ± 1°C. Novelty impact statement In recent years, there has been an increase in demand for value-added fish-based products. Food industries are adopting novel processing and cooking processes to develop an array of items in order to accomplish consumers’ changing preferences. The findings of this study will have a substantial impact on the food industry by enabling the manufacture of novel products such as shrimp analogs produced from surimi of low-cost pangasius fish with enhanced nutritional content. The preparation process is simple, appealing, affordable, unique, and sustainable. According to the findings of the current study, vacuum packaging is helpful in extending the shelf-life of the shrimp analog during refrigerated storage.

Immobilization of phlorotannins on nanochitin: A novel biopreservative for refrigerated sea bass (Lateolabrax japonicus) fillets

A novel biopreservative was developed by immobilizing phlorotannins into nanochitin (NCh). NCh were selected as a host complex to immobilized phlorotannins and the structural properties and antioxidant activity of the NCh-phlorotannins nanocomplex was investigated. The NCh-phlorotannins showed high antioxidant activity, as evidenced by free radical scavenging activity test. Moreover, the effects of NCh-phlorotannins on physical [color, water holding capacity (WHC), and texture], chemical [thiobarbituric acid (TBA) values, total volatile base nitrogen (TVB-N), and pH], microbiological [total viable count], changes of refrigerated sea bass (Lateolabrax japonicus) fillets were also evaluated. Sea bass fillets add with 1.5 g/kg NCh-phlorotannins had lower bacterial growth, pH, TVB-N and TBA as well as better characteristics of texture, color, and WHC than those of the control group during refrigerated storage. The efficiency of NCh-phlorotannins treatment was also better than that of phlorotannins or NCh treatment alone. Therefore, NCh-phlorotannins may be a potential biopreservative to extend the shelf-life of sea bass fillets quality during refrigerated storage.

Storage stability of Pangasius cutlet under refrigerated conditions

In the present study, quality changes of the fish cutlets prepared from the mince of pangasius (Pangasianodon hypophthalmus) using sensory and biochemical methods during refrigerated storage were investigated. A storage study was conducted to find out the shelf-life of the product under refrigerated conditions for 12 days. The initial values of moisture, crude protein, fat and ash content of the prepared cutlet were found as 54.50, 18.27, 15.40 and 4.35 percent respectively. At the end of the 12th day of storage moisture, crude protein, fat and ash content were found 50.20, 19.90, 15.60 and 4.90 per cent respectively. NPN content increased from 1.06 to 3.20 during the study. The total volatile base nitrogen contents (TVBN) increased from 5.0 to 18.60 (mg %) on the 12th day of study. Peroxide value also showed an increasing trend and was found as 11.88 (meqO2/kg) on the 12th day of the study. Similarly, the pH value increased from 6.58 to 7.20 during the study. The product was rejected by the taste panel on the 12th day of the study.

Evaluation of Nanochitosan-zein Coating Containing Free and Nano-encapsulated Mentha pulegium L. Hydroalcoholic Extract on Quality Attributes of Persian Shrimp (Fenneropenaeus persian)

ABSTRACT The present study was performed to fabricate a new biodegradable coating containing free, and nano encapsulated Mentha pulegium L. hydroalcoholic extract (MPE) with nano-chitosan (NCs)-zein (Zn) base to assess the biological, chemical, and sensory characteristics of shrimp samples during storage in the refrigerator for 12 days. Various concentrations of cholesterol: soy-lecithin (0:60, 10:50, 20:40, and 30:30) were used to prepare nanoliposomes. The chemical and biological properties results showed that the NCs-Zn-N (nano) MPE group had the highest effect during storage. The pH, peroxide values, thiobarbituric acid reactive substances, total volatile base nitrogen, total viable counts, TPC, and lactic acid bacteria were 7.6, 1.3 meq. kg−1, 0.17 MDA.kg−1, 30 mg.100 g−1 7.9 CFU.g−1, 8.2 CFU.g−1, and 6.4 CFU.g−1, respectively, for NCs-Zn-NMPE on the 12th day. Based on the results, NCs-Zn coating with MPE-loaded nanoliposomes can be used as a safe and suitable coating to increase the shelf life of shrimp.

The Evaluation of Oyster Marinating (Crassostrea Gasar) and Pasteurization Process in Vacuum Packaging during Storage

ABSTRACT The evaluation of oyster marinating (Crassostrea gasar) and pasteurization process in vacuum packaging during storage. The aim of this study was to establish better conditions for marinating and pasteurization for oysters (Crassostrea gasar) and to evaluate their shelf life. Microbiological, physicochemical and sensory analyzes were carried out on the oysters and on the optimized product. In the vacuum-packed product, under refrigeration, pH, water activity (aw), total volatile bases (N-TVB) and texture analyzes were performed, every 7 days for 35 days. Oysters had a high protein, mineral and amino acid content and a low lipid content. Planning 23 and 221 hour, 2.5% acetic acid, 1% NaCl and pasteurization was 62°C/2 min. Sensory analysis achieved acceptability above 80%. Marinated oysters remained suitable for consumption for 21 days, being an alternative to extend the shelf life and add value.

Effects of different plant (Marjoram and Olive leaf) extracts on quality characteristics of red and ordinary muscles of vacuum–packaged tuna–like fillets

A comparative study on the effects of marjoram (ME) and olive leaf (OLE) extracts on the quality parameters of red and ordinary muscles of tuna–like fillets kept under vacuum–packaging at refrigerated storage were investigated in this study. Tuna–like (Auxis thazard) fillets were dipped in sterile plant extract solutions (0.5% w/v) for five minutes and vacuum–packaged. Chemical, microbiological, and sensory assessments were performed on each of the muscles throughout the 18 days of the refrigerated storage. Several quality indices were significantly lower (P < 0.05) in ordinary muscle than in red muscle. However, the quality parameters of both muscles had the same tendency and were significantly affected by time as well as by the applications of plant extracts. Sensory assessments showed that both muscles from tuna–like fillets had 12 days of shelf–life, while OLE and ME applications extended significantly (P < 0.05) the shelf–life of both muscles for 3 and 6 more days, respectively. Microbiological analyses and total volatile base–nitrogen (TVB–N) assessment revealed a longer shelf–life for all samples, whilst thiobarbituric acid reactive substances (TBA) analysis suggested that vacuum–packaging alone was sufficient to delay lipid oxidation of fish fillets, especially on dark muscle. However, the application of ME was more effective in prolonging the shelf–life of vacuum–packaged tuna–like fillets. Thus, the employment of OLE or ME improved the quality parameters of fillets throughout the experiment and can be used by the fish processing industry.

Effect of ultrasonic thawing on the physicochemical properties, freshness, and protein-related properties of frozen large yellow croaker (Pseudosciaena crocea).

Ultrasonic treatment (UT) was used to thaw large yellow croaker in this study, and the effect of various ultrasonic power levels on the quality of large yellow croaker was evaluated after thawing. The effects of ultrasonic on water holding capacity (WHC), moisture distribution, thiobarbituric acid-reactive substance (TBARs), total volatile base nitrogen (TVB-N), ATP degradation (related to K value), surface color change, free amino acid (FAA) content, total sulfhydryl group (SH) content, Fourier transform infrared absorption spectra (FT-IR), fluorescence emission spectra, and microscopic observations of large yellow croaker myofibrillar proteins were investigated. The thawing times of the control sample, 200UT, 240UT, 280UT, and 320UT samples were 1750, 1190, 810, 580, and 570 s, respectively, which indicated that ultrasonic radiation could improve thawing efficiency. Additionally, ultrasonic thawing maintained better freshness and color and inhibited lipid oxidation. Compared with fresh samples, the TVB-N of large yellow croaker thawed by ultrasonication increased by 12.68%, and the K value increased by 0.9%. The 240UT sample had tightly arranged myofibrils and fewer changes in the structures of myogenic fibrillar proteins than the fresh samples, and the SH content of 240UT was decreased by 8.17%. Use of excessive ultrasonic power (320 W) damaged the protein microstructure and the microstructure of large yellow croaker. In conclusion, sample 240UT maintained the quality of large yellow croaker better with minimal damage, which is recommended for rapid thawing. PRACTICAL APPLICATION: Ultrasonic waves improve the thawing efficiency of large yellow croaker and maintain the freshness and color of the fish. According to results, sample 240UT exhibited slight changes in the structure of the myofibril protein, but excessive ultrasonic power destroyed the microstructure and protein structure. Appropriate ultrasonic treatment to the thawing of fish has good prospects.

Development of shelf-stable, ready to cook (RTC) intermediate moisture (IM) shrimp and its shelf life extension using hurdle technology

Frozen shrimp is a major commodity exported from India. A hurdle technology was employed for the shelf life extension of intermediate moisture (IM) shrimp at ambient temperature. The shrimps were salted (10% w/v), dried in an infra-red dryer (60 °C, 6–8 h) to the moisture level of 30–32%, packaged in PET/POLY (polyethylene terephthalate) bags, subjected to gamma radiation (5 kGy) and stored at ambient temperature (26–28 °C) for 6 months. Initial bacterial count (TBC) was 3.20 ± 0.26 and 1.61 ± 0.09 log CFU/g for control and irradiated (5 kGy) samples respectively. TBC reduced to 2.03 ± 0.17, 0.36 ± 0.09 log CFU/g for control and 5 kGy samples respectively after 6 months of storage at room temperature. The total volatile base nitrogen (TVBN) content was increased to 95.22 ± 4.78, 84.72 ± 2.58 mg N/100g for control and 5 kGy samples from initial value of 33.20 ± 0.40 and 33.32 ± 0.40 mg N/100g respectively. Similarly, trimethyl amine (TMA) content was found to be increased from 4.54 ± 0.62, 6.31 ± 0.22 to 25.03 ± 0.84, 23.59 ± 1.02 mg N % in case of control and irradiated sample respectively. Initial thiobarbituric acid reactive species (TBARS) content of control and 5 kGy sample was 1.85 ± 0.06 and 2.89 ± 0.13 μg malonaldehyde (MDA)/g respectively which was further enhanced to 9.18 ± 1.13 and 6.36 ± 0.41 μg MDA/g. However, based on sensory evaluation, control samples were acceptable till 4-months with sensory score of 3.78 ± 0.34 whereas irradiated samples were acceptable till 6 months of storage with sensory score of 4.5 ± 0.73. We conclude that hurdle treatments (salting, drying and irradiation) can be efficiently employed to develop shelf-stable, microbiologically safe IM shrimp with improved sensory quality and economic value. • Shelf-stable, hygienic and safe Intermediate Moisture (IM) shrimp. • Salting, infra-red drying and gamma irradiation were used as hurdles. • Well acceptable sensory, texture quality with good rehydration capacity. • Ensures longer availability during lean season and to distant/remote places. • Economically beneficial to processers, suitable for import and export.

Bacterial Diversity of Sun-Dried Spanish Mackerel in Dalian and Application of Lactobacillus plantarum X23 as a Biopreservative

Sun-dried Spanish mackerel is a common food in Dalian and made by adding salt and sun drying, which has special physical, chemical, and microbiological properties. In this study, the physicochemical properties and microbial composition of commercially available sun-dried Spanish mackerel in Dalian were assessed, and some Lactobacillus strains were screened as a biopreservative for sun-dried Spanish mackerel preparation. The results showed that the total volatile base nitrogen content in the traditional sun-dried Spanish mackerel samples from Dalian was within 30 mg/100 g, the histamine content was 7 to 17 mg/kg, and the dominant bacteria at the genus level were Lactobacillus, Psychrobacter, and Ralstonia. A strain with biopreservative potential was isolated from a sun-dried Spanish mackerel sample, identified as L. plantarum species by 16S rDNA sequencing, and assigned as L. plantarum X23. Fresh Spanish mackerel flesh was treated with 16% brine and L. plantarum X23 at a dose of 107 CFU/mL and then dried in the sun. The sun-dried Spanish mackerel flesh treated with 16% brine and L. plantarum X23 showed a decreased histamine and acid value, increased free amino acid content, and a higher sensory score compared with the sun-dried Spanish mackerel without L. plantarum X23 treatment (P < 0.05). In conclusion, the sun-dried Spanish mackerel purchased from the supermarkets in Dalian were safely edible, and L. plantarum X23 can significantly reduce the content of histamine and putrescine in self-made, low-salt, sun-dried Spanish mackerel and has potential as a biopreservative for sun-dried Spanish mackerel preparation.

Improvement of the microbial quality, antioxidant activity, phenolic and flavonoid contents, and shelf life of smoked herring (Clupea harengus) during frozen storage by using chitosan edible coating

Smoked herring is a very popular traditional fish product widely consumed in Egypt. Nonetheless, rapid mould growth and lipid oxidation, with consequent short shelf life and loss of the essential characteristics, including the smoking color and flavor, are emerged as adverse problems during storage of this product. This study was aimed to improve the quality and lipid stability of smoked herring using chitosan coating. To achieve this goal, smoked herrings were collected from local producers and divided into 5 groups, including two controls (water-dipped and 0.5% lactic acid-dipped samples) and three treated groups (2%, 3% and 4% chitosan-coated samples) followed by storage at −18 °C for 3 months during which microbiological, physicochemical, and sensorial analyses, besides determination of phenolics, flavonoids, and the antioxidant activity were carried out. The results revealed that chitosan-coated (3% and 4%) samples exhibited more than 4 log 10 CFU/g reduction in aerobic plate count, along with complete suppression of psychrotrophic, Enterobacteriaceae, yeast and mould counts, which were all under the detectable levels (2 log 10 CFU/g). Chitosan improved and maintained the phenolic and flavonoid compounds along with the free radical scavenging activity in chitosan-coated smoked fish during frozen storage. Moreover, chitosan coating induced significant improvement of the physiochemical quality including; pH, total volatile base nitrogen, trimethylamine, thiobarbituric acid values, free fatty acid %, acid number, together with the sensory attributes, compared to control uncoated ones. The study concluded that chitosan coating can be a good choice for fish industry to overcome the problems that arise in smoked fish. • The first study determined phenolics and flavonoids in chitosan-coated smoked fish. • Chitosan improved and maintained phenolics and flavonoids in stored smoked herring. • Chitosan has a potent antimicrobial effect in smoked herring during frozen storage. • Chitosan exerted a strong antioxidant activities in frozen-stored smoked herring. • Chitosan improved the chemical & sensory quality of smoked herrings during storage.

Combined effects of ultrasound and slightly acidic electrolyzed water on quality of sea bass (Lateolabrax Japonicus) fillets during refrigerated storage

A novel technique for sea bass (Lateolabrax Japonicus) fillets by combining ultrasound (US) and slightly acidic electrolyzed water (SAEW) to inactivate bacteria and maintain quality was developed. Samples were treated with distilled water (DW), US, SAEW and ultrasound combined with slightly acidic electrolyzed water (US + SAEW) for 10 min, respectively. The results suggested that US + SAEW treatment could retard the increase of total viable counts (TVC), Pseudomonas bacteria counts and H2S-producing bacteria counts, which also inhibit the rise of total volatile basis nitrogen (TVB-N), thiobarbituric acid (TBA), pH and K value. In addition, compared with SAEW or US treatment alone, US + SAEW treatment had distinctly effects on inhibiting protein degradation and maintaining better sensory scores. Compared with DW group, the shelf life of sea bass treated with US + SAEW was increased for another 4 days. It indicated that the combined treatment of US and SAEW could be used to the preservation of sea bass.

Multifunctional bioactive coatings based on water-soluble chitosan with pomegranate peel extract for fish flesh preservation

This study aimed to reveal the effects of vacuum-impregnated carboxymethyl chitosan (CMCS) coating with pomegranate peel extract (PPE) on quality retention of fish flesh during refrigeration. Herein, CMCS-PPE coating was effective in attenuating quality loss of grass carp fillets. Compared to Control, the levels of drip loss, total volatile base nitrogen, and K value in coated samples were sharply decreased (p < 0.05) by 24.5%, 35.3% and 25.2% on day 9, respectively. Meanwhile, the coating also helped inhibit oxidation, bioamine accumulation, and texture softening in fillets. Moreover, the microbial enumeration was reduced by >1.4 lg cfu/g as compared to Control on day 6 afterward, and high throughput sequencing analysis further showed the active coating contributed to the notable growth suppression of spoilage bacteria like Shewanella. Additionally, the positive effect of the coating scheme was also verified in longsnout catfish and snakehead, further confirming its good applicability for fish flesh preservation.

Development and Characterization of Semi-Refined Iota Carrageenan/SiO2-ZnO Bionanocomposite Film with the Addition of Cassava Starch for Application on Minced Chicken Meat Packaging.

In the current study, film based on semi-refined ι-carrageenan/cassava starch (SRiC/CS) incorporated with SiO2-ZnO nanoparticles was fabricated and characterized to deal with serious environmental problems resulting from plastic packaging materials. This study aimed to evaluate film properties with the variation of SRiC/CS proportions of bionanocomposite films for application to minced chicken meat packaging. Increasing CS portion contributed to increased transparency, reduced surface roughness, and decreased mechanical properties of films. The variable significantly (p < 0.05) increased the water vapor permeability (WVP) and reduced the water solubility of films. The incorporation of the nanoparticles significantly (p < 0.05) increased UV screening, decreased WVP, and enhanced the antimicrobial activity of films. Furthermore, the substitution of 0.5 wt% (weight percentage) CS provided the best film characteristics. Based on the color and the total volatile base nitrogen (TVBN) results, SRiC film incorporated with the nanoparticles preserved minced chicken quality up to six days. Thus, the developed films are desirable for biodegradable food packaging.