Potassium Sorbate Treatment Research Articles

Inactivation effects of combined thermosonication and potassium sorbate treatments on Bacillus subtilis spores.

This study aimed to investigate the inactivation effect of combined TS (thermosonication) and PS (potassium sorbate) treatments on Bacillus subtilis spores. The inactivation effect and potential mechanisms were examined using plate counts, OD600 values, nucleic acid leakage, DPA (dipicolinic acid) leakage, flow cytometry, and FTIR (Fourier transform infrared spectroscopy). The results showed that, after TS + PS treatments, the integrity of the inner membrane was lost, the permeability of the inner membrane to water molecules was increased, and the intraspore substances leaked. Furthermore, the OD600 value was reduced, indicating that the spore core hydration was enhanced. Spores proportion with damaged inner membrane was significantly increased to 66%, the ordered secondary structure of the protein was changed into a disordered structure and nucleic acid was fragmented after TS + PS treatment. The results indicated that the combined TS and PS treatments may be a useful method for inactivating bacterial spores in food processing and sterilization.

Antibacterial mechanism of thermoultrasound combined with potassium sorbate against Pichia membranifaciens

The effect of the antimicrobial mechanism of ultrasound (US) in combination with heat (T) and potassium sorbate (PS) treatment on Pichia membranifaciens (P. membranifaciens) is investigated in this study. It is found that ultrasound combined with heat (thermoultrasound [TS]) exhibits a synergistic inactivation efficiency, and the combinations of US, T, and TS with PS also improve inactivation efficacy through reductions of 0.32 ± 0.02 log, 0.73 ± 0.04 log, and 4.50 ± 0.04 log in P. membranifaciens achieved using US + PS, T + PS, and TS + PS, respectively. Further, use of the TS + PS treatment leads to cytoplasmic leakage and a decrease in dehydrogenase activity, as well as a significant increase in cell membrane permeability, causing membrane depolarization and the inward flow of extracellular calcium ions. In addition, the cell membrane composition is detected by infrared spectroscopy, demonstrating that TS + PS treatment results in a decrease in lipid and protein content and an increase in phospholipid content in the cell membrane. Scanning and transmission electron microscopy reveals a deformed cell structure and damage to cell membrane integrity after TS + PS treatment. In addition, the expression of heat shock protein (Hsp82 and Hsp70) genes is shown to decrease after TS and TS + PS treatment compared to the T and T + PS treatment groups, indicating cellular homeostasis has been broken and cells are responding to the damage by activating the protective gene expression program.

A comparative study on the antifungal effect of potassium sorbate, chitosan, and nano-chitosan against Rhodotorula mucilaginosa and Candida albicans in skim milk acid-coagulated (Karish) cheese.

Yeasts are common contaminants in the cheese industry, which frequently arise from raw milk, the surrounding environment, and equipment, resulting in economic losses in addition to health hazards. This study aimed to compare the antifungal effect of chitosan and nano-chitosan as natural preservatives with a commonly used chemical preservative (potassium sorbate) against Rhodotorula mucilaginosa and Candida albicans. Laboratory Karish cheese was manufactured with the addition of potassium sorbate, chitosan, nano-chitosan, and their combinations at different concentrations. The survival of R. mucilaginosa and C. albicans was monitored in different treatments (CR, PR1, PR2, CR1, CR2, NR1, NR2, MR, CC, PC1, PC2, CC1, CC2, NC1, NC2, MC) during storage in a refrigerator with continuous measurement of pH. The impact of using these antifungal agents on the organoleptic parameters of Karish cheese during storage was also evaluated. There was a significant decrease in the count of yeasts in all treatments from the 3rd day of storage, while the mixture of 0.1% potassium sorbate (MR) and 2% chitosan (MC) improved the antifungal effect of chitosan with a lower potassium sorbate concentration and showed the best antifungal effects against both R. mucilaginosa and C. albicans. This combination reduced the yeast count from 8.92 and 9.57 log10 colony-forming unit (CFU)/g in MR and MC treatments, respectively, until it became undetectable on the 9th day of storage, which was earlier than for all other treatments. It was noted that the addition of chitosan nanoparticles (ChNPs) at either 0.25% (NR1 and NC1) or 0.5% (NR2 and NC2) during the manufacturing of Karish cheese significantly lowered the counts of R. mucilaginosa and C. albicans compared with chitosan with a higher molecular weight, but significantly lower than potassium sorbate until 6th day of storage as all treatments of chitosan nanoparticles became significantly higher than potassium sorbate treatments. After 9 days of storage, NR2 and NC2 treatments showed the most significant decreases in count (3.78 and 4.93 log10 CFU/g, respectively), indicating better stability of ChNPs. At the end of the storage period, PR2, PC2, CR2, and CC2 showed significantly high pH values among the groups of 4.8, 5.0, 4.8, and 5.1, respectively. The overall acceptability was significantly higher in treated Karish cheese samples than in the control group, especially at the end of the storage period. Potassium sorbate, chitosan, and ChNPs are effective antifungal preservatives against R. mucilaginosa and C. albicans. In addition, the combination of chitosan with potassium sorbate showed synergistic antifungal activity. These additives also preserve the sensorial criteria longer than for cheese without preservatives.

Effects of postharvest chitosan and potassium sorbate coating on the storage quality and fungal community of fresh jujube

Fresh jujube fruit are confronted with serious quality deterioration after harvest. This study explored the effects of chitosan and potassium sorbate coatings on the physicochemical quality and fungal community of jujube during cold storage. Microscopic observation showed that chitosan can uniformly distribute potassium sorbate on the surface of jujube. Chitosan coating inhibited the increase in respiration rate and total soluble solids and the decrease in titratable acidity and firmness. Jujube fruit treated with chitosan and potassium sorbate showed the lowest decay rate (2.67%) after 35 d of storage. High-throughput sequencing analysis indicated that the largest number of fungal amplicon sequence variants (ASVs) was detected in jujube treated with chitosan and potassium sorbate, exhibiting higher Chao1, Shannon and Simpson diversity indices. Treatment with chitosan or potassium sorbate alone reduced the relative abundance of Cladosporium in jujube fruit. Jujube treated with chitosan and potassium sorbate had the lowest total relative abundance of all potential pathogenic fungi (Cladosporium, Alternaria and Diaporthe). FUNGuild analysis showed that chitosan and potassium sorbate treatment could inhibit the relative abundance of plant pathogenic fungi. As a result, chitosan maintained the physicochemical properties of jujube by inhibiting the respiration rate, and the combination of chitosan and potassium sorbate reduced the decay rate of jujube by inhibiting pathogenic fungi. Therefore, chitosan and potassium sorbate coating is a promising approach to improve the storage quality and delay the decay of jujube fruit after harvest.

Combination of rosemary oil and potassium sorbate controls anthracnose in mango fruit by triggering defense-related enzymes

Colletotrichum gloeosporioides causes anthracnose, a severe postharvest disease in mango fruit. Due to the ban on most fungicides, alternative methods are needed to control this disease and reduce postharvest losses. In this study, the effectiveness of rosemary oil (RMO) and potassium sorbate (PS) as organic alternatives was investigated. In in vitro experiments, 1000 μLL−1 RMO and 2% PS completely inhibited the growth of C. gloeosporioides. When applied to inoculated mango fruit, the RMO + PS treatment increased antioxidant activity and phenolic metabolism compared to control and synthetic fungicide. The treatment also up-regulated the activity of defense-related enzymes, such as peroxidase (POD) and phenylalanine ammonia-lyase (PAL), indicating improved postharvest quality and reduced losses during storage at different temperatures. Further research is needed for successful commercialization of this organic edible coating in the mango fruit industry.

Effects of ultrasound combined with mild heat and potassium sorbate on Pichia membranaefaciens and the quality of soy sauce

AbstractThe aim of this study was to investigate the effects of ultrasound (US) combined with mild heat (T) and potassium sorbate (PS) on Pichia membranaefaciens in soy sauce and the quality of soy sauce. The maximum reduction of P. membranaefaciens was 5.34 ± 0.15 log after thermoultrasound (TS, 300 W, 10/3 s, 20 + 40 kHz, 60°C) + PS (0.1 mg/mL) treatment for 20 min. Physicochemical properties, including pH and total acid of soy sauce, did not change significantly after TS + PS treatment. Electronic nose analysis showed changes in the flavour of soy sauce after different treatments. A total of 122 and 125 volatile compounds were detected by SPME‐GCMS before and after TS + PS treatment respectively. T90 (soy sauce processed at 90°C) treatment decreased the content of the flavour compounds greatly, while TS + PS decreased the content of the flavour compounds slightly in soy sauce. TS + PS treatment inactivated P. membranaefaciens effectively in soy sauce and maintained and partially improved the sensory and flavour characteristics of soy sauce, which indicates that this combination technology has potential application in the commercial processing of soy sauce.

A Dietary Source of High Level of Fluoroquinolone Tolerance in mcr-Carrying Gram-Negative Bacteria.

The emergence of antibiotic tolerance, characterized by the prolonged survival of bacteria following antibiotic exposure, in natural bacterial populations, especially in pathogens carrying antibiotic resistance genes, has been an increasing threat to public health. However, the major causes contributing to the formation of antibiotic tolerance and underlying molecular mechanisms are yet poorly understood. Herein, we show that potassium sorbate (PS), a widely used food additive, triggers a high level of fluoroquinolone tolerance in bacteria carrying mobile colistin resistance gene mcr. Mechanistic studies demonstrate that PS treatment results in the accumulation of intracellular fumarate, which activates bacterial two-component system and decreases the expression level of outer membrane protein OmpF, thereby reducing the uptake of ciprofloxacin. In addition, the supplementation of PS inhibits aerobic respiration, reduces reactive oxygen species production and alleviates DNA damage caused by bactericidal antibiotics. Furthermore, we demonstrate that succinate, an intermediate product of the tricarboxylic acid cycle, overcomes PS-mediated ciprofloxacin tolerance. In multiple animal models, ciprofloxacin treatment displays failure outcomes in PS preadministrated animals, including comparable survival and bacterial loads with the vehicle group. Taken together, our works offer novel mechanistic insights into the development of antibiotic tolerance and uncover potential risks associated with PS use.

Potassium Sorbate Postharvest Treatment to Control Penicillium spp. Molds and Maintain Quality of ‘Wonderful’ Pomegranates and ‘Anna’ Apples during Cold Storage

This study was carried out for two successive seasons 2020 and 2021 in order to evaluate the efficiency dipping of Wonderful pomegranate and Anna apple fruits in potassium sorbate (K-sorb.) at 3% / 2 min to maintain fruit quality and control postharvest diseases caused by Penicillium spp. ( P. italicum and P. sp.) during cold storage. Fruits were stored at 5°C and 85-90% RH for 75 days. The reduction in linear growth was correlated to the increase in potassium sorbate concentrations. Potassium sorbet at 0.06% concentration gave the maximum inhibition of the linear growth of Penicillium spp. Also, the application of potassium sorbate showed the best results in reducing the deterioration of various physical and chemical characteristics of ‘Wonderful’ pomegranate and ‘Anna’ apple fruits during cold storage and extending its storability. Potassium sorbate treatments mitigated the incidence of fruit decay and successfully decreased fruit weight loss and increased SSC: TA ratio, the total phenolic content, and activities of peroxidase and catalase enzymes relative to the control treatment.

Aplicación de quitosano y sustancias GRAS en el control de Geotrichum candidum aislado de frutos de jitomate (Lycopersicum esculentum L.) en el estado de Nayarit, México: Pruebas in vitro

Geotrichum candidum causal agent of tomato sour rot, has the potential to infect a wide variety of fruits and vegetables. In this work, the in vitro antifungal activity of Chitosan (Chi), Potassium Sorbate (PS), Sodium Bicarbonate (SB), and Sodium Carbonate (SC) and their mixtures were evaluated. The PS and SC treatments showed a 100% inhibition of mycelial growth (MG), germination, and sporulation. Regarding SB, 1.5 and 2.0% concentrations inhibited 87.5 and 88.5% of MG and affected germination and sporulation. Chi at 1.0, 1.5, and 2.0% inhibited MG by 63.1, 62.4, and 42.1%, respectively, affecting germination and sporulation. The combination of chitosan at 0.5% + PS 0.5% and Chi 0.5% + SC 0.5% demonstrated 99.3 and 71.4%, inhibition of MG, and affected germination and sporulation. Chi 0.5% + SB 1.5% showed no effect on MG, and at 0.5 and 1.0%, the growth rate of the mycelium increased, as well as sporulation and germination. In conclusion, chitosan and salts are an option for the use of synthetic fungicides in the control of pathogenic fungi in postharvest, with low toxicity, and are friendly to the environment.

Effects of Different Preservatives on the Storage Quality of Roasted Flake

To prolong the shelf life of roasted squid fillets, different preservatives including potassium sorbate, nisin and poly-lysine were utilized through 37 ℃ accelerated experiments to investigate its effect on quality of roasted squid fillets during seven days storage. Changes of TVB-N content, total microbial colony, microstructure, pH and color were evaluated. Results showed that on the 7th day of storage, compared with grilled squid slices treated by potassium sorbate and e -polylysine group and untreated group, the content of TVB-N in the grilled squid slices treated by Nisin decreased by 2.35, 8.123 and 9.612 mg·100 g−1 respectively. The total number of colonies in control group and potassium sorbate treatment group exceeded the national standard at the 5th day, which was 4.59 and 4.48 lg CFU·mL−1. The total number of colonies in e -polylysine treatment group exceeded the national standard at the 6th day, with the content of 5.08 lg CFU·mL−1. The total number of bacterial colonies in the Nisin treated group did not exceed the national standard during storage. The color, texture and sensory scores of grilled squid treated with different preservatives were significantly different (P<0.05). Compared with e-polylysine and potassium sorbate, nisin could effectively inhibit the increase of the content of TVB-N and the total number of colonies, slow down the changes of texture and color of the grilled squid, and maintain the grilled squid with good sensory properties, which is more beneficial to the storage of the grilled squid.

Impact of chitosan in combination with potassium sorbate treatment on chilling injury and quality attributes of pomegranate fruit during cold storage.

The impact of chitosan (CH) and potassium sorbate (PS) on quality attributes of pomegranate fruits (cv. Malas e Saveh) was evaluated during 90days of storage at 4°C and 85%-90% relative humidity. The CH as well as the combined treatments (CH+PS) were effective in decreasing the chilling injury (CI) symptoms, electrolyte leakage, and malondialdehyde contents of fruit peel. Furthermore, CH, PS, and CH+PS treatments enhanced the activity of DPPH radical scavenging, and antioxidant enzymes of arils, and preserved the ascorbic acid content at high levels during the storage period. Fruits treated with CH1% + PS10% and CH2% + PS10% exhibited the lowest decay incidence and weight loss. Higher content of arils' phenols, flavonoids, and anthocyanin was observed in treated-fruits as a result of more activity of phenylalanine ammonia-lyase (PAL) and low activity of polyphenol oxidase (PPO). Consequently, CH+PS showed positive effects on the storage life of pomegranate fruits in terms of CI, decay incidence, and also nutritional values. PRACTICAL APPLICATIONS: Enhancement of chilling tolerance of pomegranate fruits during cold storage condition is a crucial issue. Application of CH coating alone or in combination with potassium sorbate could decrease the CI symptoms and preserved peel cell membrane integrity by maintaining electrolyte leakage (EL) and malondialdehyde in lower levels. Also, these treatments prevent weight loss and decay incidence in peel, and increase the activity of phenylpropanoid pathway and antioxidant systems in arils. All in all, usage of CH edible coating (2%) plus PS (10%) illustrated high efficiency in alleviating CI, decay incidence, and preserving nutritional quality of pomegranate fruits.

Effect of heat shock and potassium sorbate treatments on gray mold and postharvest quality of ‘XuXiang’ kiwifruit

We determined whether heat and chemical treatments could reduce the decay of kiwifruit caused by Botrytis cinerea during postharvest storage. Kiwifruits were treated with 5 g/L (w/v) potassium sorbate (PS), with a 48 °C hot water treatment (HT), and with a combined treatment (HT + PS). Mycelial growth of B. cinerea and the postharvest quality of ‘XuXiang’ kiwifruits were evaluated. HT + PS significantly inhibited mycelial growth, germ tube growth, and spore germination of B. cinerea. This treatment also reduced the incidence of gray mold in kiwifruit postharvest, and enhanced activities of defense-related enzymes in kiwifruit tissues. Compared with the control, all treatments resulted in lower malondialdehyde (MDA) contents and higher total phenolic contents in kiwifruits. HT + PS also increased the activities of chitinase and β-1,3-glucanase and the transcript levels of their encoding genes. HT + PS can improve kiwifruit quality and reduce decay during postharvest storage.

Potasyum Sorbat ve Karanfil Yağının (Syzygium aromaticum, L.) Soğutulmuş Kerevitlerde (Astacus leptodactylus) Kalite Değişimi Üzerine Karşılaştırmalı Değerlendirmesi

In this study, comparative assessment of potassium sorbate and clove oil (Syzygium aromaticum L.) on the quality characteristics of crayfish (Astacus leptodactylus) during storage at 2°C for 20 days has been investigated. Both potassium sorbate and clove oil application retarded lipid oxidation during 20 days of storage. There were no significant differences between peroxide values (PV) of potassium sorbate and clove oil treated crayfish samples. At day 20, CO1 group showed the lowest FFA content. Least TMAB was observed in 1% clove oil treated samples throughout the storage period. Clove oil treated samples had significantly lower PBC then the control and potassium sorbate treated crayfish samples during storage period. After 10 days of storage, control samples were microbiologically unacceptable. 1% clove oil treatment was more effective than 1% potassium sorbate treatment in preventing growth of molds and yeast throughout the storage period.

Contribution of surface application of chitosan–thyme and chitosan–rosemary essential oils to the volatile composition, microbial profile, and physicochemical and sensory quality of dry-fermented sausages during storage

The effect of chitosan (C), chitosan enriched with thyme (CT) or rosemary (CR) essential oils, and potassium sorbate (PS) against superficial fungal growth was investigated in fermented sausages during 3 months of storage at 4 °C. For control groups, distilled water (DW) and acetic acid (AA) were used. PS, C, CT and CR treatments inhibited fungal growth on casings while they resulted in lower Gram(+) catalase(+) cocci, Enterobacteriaceae, mold and yeast counts in sausages. Lower TBARS values were determined for CT and CR (p < .05). A total of 44 and 64 volatile compounds were identified in sausages and casings, respectively. Sausages coated with C, CT or CR had acceptable sensory attributes at the end of storage; however, DW and AA groups were rejected in the second and third month (p < .05), respectively, due to intense fungal growth which resulted in sensory defects.

Effect of the combined action of potassium sorbate and irradiation on the quality-maintenance of strawberries.

A relatively short storage life is considered a major problem for the transportation of strawberries across long distances to markets and for exportation. The aim of this research is to study the combined effects of potassium sorbate and radiation (3kGy) on the microbial load, shelf life and most of the biochemical constituents such as vitamin C and total soluble solids of strawberries. A potassium sorbate (1%) treatment was combined, in practical application, with irradiation (3kGy) to extend the shelf life of strawberries. All strawberry samples were stored at 4 ± 1°C (90-92% RH). Quality assessment of the microbial and biochemical constituents, vitamin C, and TSS during the storage period was performed. The results showed that Gamma irradiation alone at 3kGy extended the shelf life of strawberries to 21days. Further extension of the shelf life to 21days was obtained when irradiation (3kGy) was combined with potassium sorbate treatment. All treatments caused non-significant decreases in vitamin C content during storage, except for the treatment of strawberries with a solution of potassium sorbate, which caused a significant decrease in the vitamin C content, and a gradual decrease in the vitamin C content occurred with an increase in storage time for all treatments.

The effect of different pretreatments on the quality of ready-to-eat jellyfish Rhopilema esculentum Kishinouye products

The aim of this study was to characterize the effects of different pretreatments on ready-to-eat jellyfish products. Salted jellyfish umbrella edges were used as raw materials. After desalting, samples were blanched under different temperatures for different periods of time. Moisture contents and color characteristics of the pretreated samples were determined, and texture characterized. Masson staining was used to image microstructures, and sensory evaluation was performed. Microbial growth at 37 °C was monitored for samples which underwent the different treatments. Moisture content and whiteness decreased with extended heating, and the higher the temperature, the faster these changes occurred. The moisture content of samples with no heat treatment was 97.89 ± 0.23%, which was nearly 3% higher than that of samples which had undergone heating. The 70 °C heat treatment had a greater effect on the whiteness of jellyfish. Samples exposed to the 60 °C treatment for 1 min had the highest sensory scores, and in conjunction with other results, this temperature was chosen to be the optimal heat treatment. The combination of heating, acid soaking, ultraviolet sterilization and potassium sorbate treatment was shown to prolong the shelf life of jellyfish products effectively.

Characterization of a broad host-spectrum virulent Salmonella bacteriophage fmb-p1 and its application on duck meat

The aim of this study was to find a virulent bacteriophage for the biocontrol of Salmonella in duck meat. A broad host-spectrum virulent phage, fmb-p1, was isolated and purified from an duck farm, and its host range was determined to include S. Typhimurium, S. Enteritidis, S. Saintpaul, S. Agona, S. Miami, S. Anatum, S. Heidelberg and S. Paratyphi-C. Electron microscopy and genome sequencing showed that fmb-p1 belongs to the family Siphoviridae. The genome of fmb-p1 is composed of a 43,327-bp double-stranded DNA molecule with 60 open reading frames and a total G+C content of 46.09%. There are no deleterious sequences or genes encoding known harmful products in the phage fmb-p1 genome. Phage fmb-p1 was stable under different temperature (40–75°C), pH (4–10) and NaCl solutions (1–11%). The phage treatment (9.9×109 PFU/cm2) caused a peak reduction in S. Typhimurium of 4.52 log CFU/cm2 in ready-to–eat (RTE) duck meat, whereas potassium sorbate treatment (PS, 2mg/cm2) resulted in a 0.05–0.12 log reduction. Compared to PS treatment, there was significant difference in the S. Typhimurium reduction (P˂0.05) by phage treatment at both 4°C and 25°C. The results suggested that phage could be applied to reduce Salmonella, on commercial poultry products.

Growth of Staphylococcus aureus in cooked ready-to-eat ground fish as affected by inoculum size and potassium sorbate as food preservative

This study was conducted to investigate the influence of inoculum size and potassium sorbate on kinetic growth of Staphylococcus aureus in cooked ready-to-eat ground fish (CGF) prevalent retail storage temperatures. Two treatment levels (with or without 0.2% potassium sorbate) and three inoculum sizes (3.0, 4.5, or 5.5 log CFU/g) were evaluated. CGF samples were inoculated and subsequently stored at 10, 15, 20, 25, 30, and 37 °C. Growth curves at each storage temperature were fitted to Baranyi model to estimate lag time (λ, hour) and maximum growth rate (log CFU/g/h). Prediction of λ was dependent on the inoculum size and potassium sorbate treatment. Two secondary λ models (relative lag time (RLT) and hyperbola) were used to describe the variability in the growth behavior of S. aureus on CGF. RLT values were higher for treated samples (3.55, 3.16, and 2.74, respectively for 3 inoculum sizes) than those obtained from untreated samples (3.49, 3.01, and 2.34) and decreased with increasing the inoculum size. Hyperbola model indicated considerable variability but no systematic trend was observed. Relative error within acceptable prediction zone was higher than 80% for overall secondary models developed. This supported that the developed models demonstrated acceptable performance under examined temperatures.

Effects of potassium sorbate and Lactobacillus plantarum MTD1 on production of ethanol and other volatile organic compounds in corn silage

Abstract Ethanol and other volatile organic compounds (VOC) are formed during ensiling, and may contribute to poor air quality and reduce feed intake by animals. Chemical or biological additives may help address these problems by reducing production of VOC during ensiling. The purpose of this study was to evaluate the effect of additives on production of nine silage VOC in corn silage, including compounds thought to contribute to poor air quality or affect feed intake (alcohols: methanol, ethanol, 1-propanol; esters: methyl acetate, ethyl acetate, ethyl lactate; and aldehydes: acetaldehyde, valeraldehyde, hexanal). Potassium sorbate, an anti-fungal additive that has shown promising results in reducing ethanol and ester concentrations (1 g/kg on a fresh mass basis); a facultative heterofermentative lactic acid bacterium, Lactobacillus plantarum MTD1 (105 cfu/g on a fresh mass basis); and a combination of both additives were compared to a control treatment, which received only water. Silage was made in bucket silos which were opened after 119 days of ensiling. Potassium sorbate reduced ethanol production by >70% and ethyl lactate and ethyl acetate by >65% whether or not L. plantarum was included. Other compounds were not clearly affected by either additive when used individually, but the combined treatment reduced 1-propanol and valeraldehyde. The concentration of valeraldehyde was increased by L. plantarum. Neither potassium sorbate treatment increased concentrations of any measured VOC. These results provide additional evidence that potassium sorbate is an effective additive for reducing production of ethanol and ethyl esters in corn silage. Combining potassium sorbate with L. plantarum may provide additional benefits, although the persistence of this effect for silages with higher VOC concentrations needs to be evaluated.

EFFECT OF POTASSIUM SORBATE AND MODIFIED ATMOSPHERE PACKAGING ON THE SHELF-LIFE EXTENSION OF SEER FISH (SCOMBEROMORUS COMMERSON)STEAKS DURING ICED STORAGE

ABSTRACT A study to evaluate the influence of potassium sorbate combined with modified atmosphere packaging (MAP) at 2C on the shelf-life extension of seer fish (Scomberomorus commerson) steaks was made. The shelf life of 12 days in air pack was extended by 10 and 18 days in MAP and modified-atmosphere-packed seer fish pretreated with potassium sorbate, respectively. K value was not a suitable predictor of shelf life for seer fish. Potassium sorbate treatment showed further inhibition of total aerobic mesophilic count while sulfite reducing clostridial counts were 1 log cfu/g in all the packs after day 12 of storage. Potassium sorbate treated MAP samples showed higher sensory score on day 25 than those observed for MAP (P < 0.05) and CMAP steaks. Significant extension (P < 0.05) in shelf life was noticed due to MAP and treating samples with potassium sorbate. PRACTICAL APPLICATIONS The present study suggests that modified atmosphere 70% CO2 : 30% O2 extended shelf life of seer fish by 10 days. By using 70% CO2 : 30% O2 with 2% potassium sorbate, the shelf life of seer fish was further extended by 18 days compared to air pack which served as control and this particular combination could be commercially exploited. As the optimal gas composition varies depending on the fish, this paper adds new research information on preservation of seer fish. Moreover, as seer fish has high export demand, proper preservation technique suggested in this paper is highly relevant.