Dipping Solution Research Articles

Remediation of leached iron ions from real dip-coating waste solution using biodegradable hydrogels prepared by gamma rays

Dip-coating is one of the most commercially applied coating processes for metals. The excess of iron ions in the dipping solution, which is formed as a result of repeated dipping in the same bath several times, reduces the efficiency of the solution. In this research, polymeric hydrogel based on tannic acid (PEG/PAm/CMC)/TA via gamma irradiation was prepared as an efficient and clean method to remove the excessive content of Fe ions leached in the dipping precursor solution. Swelling characteristics and gelation content of the prepared samples were studied. The best copolymer composition was (1:5:1:1) wt% for (PEG/PAm/CMC)/TA, respectively with a total polymer concentration of 30 wt%. Change in the chemical and physical structures of the prepared hydrogel was studied using FTIR and XRD. The topographic surface of the prepared hydrogel and distribution of adsorbed Fe ions were studied using an SEM and EDX respectively. The adsorption kinetics study reveals that the chemical reaction follows second-order reactions. The linearity in the Freundlich adsorption model reveals a maximum multilayer adsorption capacity of (230) mg/g for the (PEG/PAm/CMC)/TA hydrogel. The results also indicate that the biodegradability of the prepared hydrogels increases with CMC and TA contents. The investigations concluded that the prepared hydrogel could efficiently absorb the iron ions leaked from the dipping solution.

Response to Letter to the Editor on "Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate".

Response to Letter to the Editor on "Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate".

Letter to Editor on "Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate".

Letter to Editor on "Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate".

Impact of postharvest dips with abscisic acid, prohexadione, calcium, or water on bitter pit incidence and apple physiology

Bitter pit causes significant losses to apple producers, packers, and retailers each year. While bitter pit is often associated with calcium deficiency, this postharvest disorder is still not fully understood. Some studies have demonstrated positive effects of preharvest sprays with prohexadione and abscisic acid. To evaluate the effects of these phytohormones as postharvest dips, ‘Granny Smith’ apples were dipped after harvest in prohexadione-Ca, abscisic acid, or CaCl2. Undipped and water dipped fruit were included as controls. Bitter pit incidence and severity were evaluated on fruit stored at 0 °C and >90 % RH for 68–75 d. Postharvest prohexadione-Ca and abscisic acid treatments did not reduce bitter pit incidence over two years of testing. However, there was an increase in bitter pit incidence in control fruit dipped in water and surfactant compared to undipped control fruit in the first year of testing. This increase (7.5–14 %) was observed again in water dipped control fruit in each of the following 2 years of experimentation. Inclusion of 1 % calcium chloride in the dip solution eliminated this increase in bitter pit incidence. Applying calcium with a surfactant increased the apoplastic calcium concentration and reduced bitter pit development compared to water dipped fruit. Results indicate that the increase in bitter pit induced by water dips may be due to removal of residual calcium on the fruit’s surface from preharvest calcium treatments. Ethylene production was higher in bitter pit fruit compared to healthy fruit. Reduced and total ascorbate were decreased in pitted fruit compared to healthy calcium dipped fruit. Dichlorofluoresceine diacetate fluorescence was higher in tissue adjacent to pits compared to healthy tissue from healthy fruit, indicating accumulation of reactive oxygen species. However, no consistent trend was observed in antioxidant enzyme activity. These results indicate that bitter pit shares some, but not all, of the oxidative metabolic trends observed in other fruit calcium deficiency disorders.

Tailoring the properties of carbon molecular sieves membranes for the separation of propionic acid from aqueous solutions

In the fermentative production of propionic acid (PA), the major problem with batch fermentation systems is the strong inhibitory effect of PA on the production yield; one way to increase the yield is the in-situ removal of PA by using pervaporation. Acetic acid (AA) is the most important by-product in the fermentation; therefore, the membrane should be able to remove selectively PA from an aqueous solution containing AA. Considering that PA is more hydrophobic than AA and their kinetic diameter are 0.480 and 0.436 nm respectively, hydrophobic membranes with main pores in the range of around 0.5–0.6 nm with high permeation are required.Supported thin Carbon Molecular Sieve Membranes (CMSM) were prepared by the dip coating a porous alumina support into a solution containing resorcinol phenolic resin as carbon source. The hydrophobicity was obtained by carbonizing the polymer at temperatures higher than 750 °C and adding polyvinyl butyral (PVB) as pore forming agent and carbon contributor. PA with 88 % of purity was obtained by pervaporation of an aqueous solution containing 5 % of PA and 5 % of AA using a CMSM carbonized at 850 °C containing 1 % of PVB in the dipping solution.

A multi-functional coating on cotton fabric to incorporate electro-conductive, anti-bacterial, and flame-retardant properties

Multi-functional textiles have become a growing trend among smart customers who dream of having multiple functionalities in a single product. Thus, this study aimed to develop a multi-functional textile from a common textile substrate like cotton equipped with electrically conductive, anti-bacterial, and flame-retardant properties. Herein, a bunch of compounds from various sources like petro-based poly-aniline (PANI), phosphoric acid (H3PO4), inorganic silver nanoparticles (Ag-NPs), and biomass-sourced fish scale protein (FSP) were used. The coating was prepared via in-situ polymerization of PANI with the cotton substrate, followed by the dipping in AGNPs solution, layer-by-layer deposition of FSP and sodium alginate, and finally, a dip-dry-cure technique after immersing the modified cotton substrate into the H3PO4 and citric acid solution. The key results indicated that the fabric treated with PANI/Ag-NPs/FSP/P-compound exhibited a balanced improvement in all three desired properties as the electrical resistance was reduced by 44.44 % while showing superior bacterial inhibition against gram-positive bacteria (S. aureus) and gram-negative bacteria (E. coli), and produced dense-black carbonaceous char residues, indicating its flame retardant properties as well. Thus, such amicable developments made the cotton textile substrate a multi-functional textile, which showed potential to be used in medical textiles, wearable electronics, fire-fighter suits, etc.

(143) ANTIFUNGALS AND LOCAL ANESTHETICS DO NOT DIMINISH ANTIBIOTIC BINDING TO PENILE PROSTHESIS HYDROPHILIC SURFACE

Abstract Introduction Recent in vitro studies have demonstrated that use of 0.05% chlorhexadine gluconate negatively alters the antimicrobial activity of the hydrophilic surface of inflatable penile prostheses. Antifungals and local anesthetics have also been proposed for use as prophylactic dips for fungal infections and post-operative pain, respectively. The effects of these therapeutics on antimicrobial activity have not been fully elucidated in current literature. Objective We aim to evaluate if amphotericin and bupivacaine compete with the binding of antibiotic solutions to the hydrophilic surface of penile prosthesis implants, thereby reducing antimicrobial activity. Methods Sterile 8 mm diameter PP discs were submerged for 3 minutes in 3 mL of normal saline (NS), 2 mg/mL vancomycin and 160 μg/mL gentamicin (VG) in NS, 0.02 μg/mL amphotericin in VG (VGA), or 0.25% bupivacaine (2.5 mg/mL) in VG (VGB), rinsed in NS for five seconds to remove any unbound solution, then incubated with 1x10^5 colony forming units per milliliter (CFU)/mL of methicillin-sensitive Staphylococcus aureus ATCC25923 (MSSA) in trypticase soy broth (TSB) for 48 hours. Samples were then rinsed with PBS and biofilm was removed by shaking in 0.3% Tween-20. Suspended bacteria were serially diluted, plated onto 3 M PetriFilms, and counted. Irrigation studies were performed to evaluate the effect of intraoperative irrigation on the binding of the prophylactic dip. The initial dip protocol was followed, with the addition of a subsequent submersion in 3 mL of either NS, VG, VGA, or VGB solution for 2 minutes to mimic intraoperative irrigation. The discs were then incubated in 1x10^5 CFU/mL of MSSA for 48 hours, plated, and counted. Disc-diffusion tests were conducted by pipetting 10 μL of NS, VG, VGA, or VGB on 6 mm implant discs and dried overnight in a laminar flow hood. Treated discs were then placed coated-side down onto plates streaked with clinical strains of the following organisms isolated from clinical penile implant infections: Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae. After 24 hours of growth, Zones of Inhibition (ZOI) were measured. Mann–Whitney U tests were performed to compare outcomes, p < 0.05 considered significant. Results Average bacterial counts with 95% CI are plotted in Fig. 1a and 1b. There were significant decreases in bacterial counts in all three treatment groups (VG, VGA, VGB) relative to NS controls (p < 0.01), both with and without irrigation. There were no significant differences in bacterial counts between the VG, VGA, and VGB group (p > 0.05). Disc-diffusion studies showed maintained antimicrobial activity across all three treatment groups against clinical strains of Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae as shown by the ZOI presented in Fig. 1c. Conclusions The addition of amphotericin or bupivacaine to the antibiotic dip solution does not adversely affect the antimicrobial efficacy of the VG antibiotic dip solution, irrespective of irrigation conditions. Antibiotic dip solutions containing amphotericin and bupivacaine also maintained antimicrobial properties across clinically isolated strains of bacteria collected from penile implant infections. Disclosure Yes, this is sponsored by industry/sponsor: Coloplast. Clarification: Industry funding only - investigator initiated and executed study. Any of the authors act as a consultant, employee or shareholder of an industry for: Coloplast and Boston Scientific.

Color Test and Screening of Alkaloid, Saponin Levels of Citrus Fruit Peel Eco-Enzyme (Citrus reticulata) Eco-enzyme Solution as a Candidate for Teat Dipping Solution in Dairy Cattle

Teat dipping is the activity of dipping the nipples of dairy cattle into an antiseptic solution that serves to coat and protect the nipples of livestock from harmful bacterial contamination so as not to cause disease in dairy cattle. This study aimed to obtain preliminary information about the color and screening of alkaloid and saponin content in the eco-enzyme solution, which will later be used as one of the natural antiseptic candidates for teat dipping solution in dairy cattle. This research uses descriptive analysis with the parameters observed, namely color and screening of alkaloid and saponin content in eco-enzyme solutions that have been diluted previously with the following percentages: A: 30% eco-enzyme solution + 70% aquades, B: 60% eco-enzyme solution + 30% aquades, and C: 100% eco-enzyme solution. From the results, it was found that the color of eco-enzyme solution A (transparent yellow), B (transparent yellow), and C (intense yellow and translucent color) while the qualitative test obtained A: positive, B: positive, C: positive (alkaloid content); A: negative, B: positive, and C: positive (saponin content). The results of color tests and screening of alkaloid and saponin content showed that good results were obtained in 100% eco-enzyme solution (C), which can be used as a candidate for natural teat dipping solution in dairy cows.

Antibiotic dip and irrigation solutions confer increased antimicrobial efficacy of inflatable penile prosthesis hydrophilic surfaces compared with 0.05% chlorhexidine gluconate.

Chlorhexidine gluconate (CHG) (0.05%) has recently been suggested as both a dip for the hydrophilic surface and an irrigation solution in the setting of penile prosthesis (PP) surgery. The study sought to compare the antimicrobial efficacy of 0.05% CHG with vancomycin and gentamicin (VG) antibiotics as dip and/or irrigation solutions in the setting of a hydrophilic PP surface in vitro. Sterile PPs with a hydrophilic coating were obtained. A series of experiments were performed to evaluate the efficacy of normal saline (NS), 0.05% CHG, or VG as dip and/or irrigation solutions to reduce methicillin-sensitive Staphylococcus aureus adhesion to PP surfaces. The 8-mm discs from PPs were incubated in 105colony-forming units/mL of methicillin-sensitive S aureus for 48hours, plated, and counted. Disc-diffusion tests were conducted by suspending 6-mm discs for 2minutes in NS, 0.05% CHG, or VG, then placing them coated side down onto plates streaked with the following organisms: methicillin-sensitive S aureus, S epidermidis, Enterococcus, and Escherichia coli. After 24hours of growth, zones of inhibition were measured. We found average bacterial counts (colony-forming units/mL) and zones of inhibition (mm) following a series of treatment protocols of PP discs. PP discs dipped in VG reduced bacterial adhesion to the implant surface >0.05% CHG (~5.5 log vs ~1.5 log; P < .01). Discs irrigated with either 0.05% CHG or NS removed all dip solution adsorbed to the hydrophilic surface, allowing bacterial growth. VG irrigation adsorbed to the hydrophilic surface even after 0.05% CHG or NS dips, reducing bacterial adherence (~3 log). Dipping and irrigating discs with VG was most effective in reducing adherent bacteria (~5.5 log) and was the only irrigation that showed antimicrobial activity. VG, when used both as a prophylactic dip and as an intraoperative irrigation solution for hydrophilic penile implant surfaces, has improved efficacy to 0.05% CHG and NS. This is the first study to compare the use of VG, 0.05% CHG, and NS as prophylactic dips and intraoperative irrigations for hydrophilic penile implant surfaces. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate nor translatable clinically. We demonstrated the superior efficacy of VG as a combined dip and irrigation solution for hydrophilic penile implant surfaces compared with 0.05% CHG.

Study on enhancement of poultry egg shelf life under room storage

Eggs are nutritious food commodities that are consumed all around the world. Freshness is a major contribution to egg quality. However, eggs are perishable and susceptible to quality losses, and contaminated with certain microorganisms during storage. Currently, there are very few companies such as Ba Huan, CP, and Dabaco in Vietnam operating technology for processing poultry eggs and most of the eggs are sold untreated (no washing or disinfection). The study aims to determine the effect of saline, hot water, and Litsea cubeba essential oil (EO) on the freshness of chicken eggs including weight loss, air cell size, Haugh unit, Yolk index, pH, total viable count properties and shelf life of eggs at 370C storage. The best preservation effect was found in the sample sprayed with L. cubeba EO at 4 mg/mL, followed by dipping in hot water at 650C for 90 s and dipping in saline solution at 0.9% for 30 s to maintain the freshness of egg. The EO-treated egg could remain at average quality for up to 16 days at 370C compared to 7 days of untreated sample. The obtained results demonstrated the potential application of natural products in food preservation.

Flexible automated system for laser modified layer by layer assembly.

An open-source automated system for laser modified layer by layer assembly is described. This flexible system, the first designed to be used with this process, can be used to fabricate a range of laser patterned, layer by layer thin films. The Arduino microcontroller-based system features a stepper motor-controlled turntable that holds solutions and water rinses for dipping. The substrate can be moved vertically to be dipped into each of the solutions throughout the process. A semiconductor laser is used to modify the thickness of the thin film during the chosen dipping cycles. Several aspects of the robotic system are easily controlled via software, including the average laser power, irradiation time, horizontal laser position, and vertical substrate position. The system is fully automated and, once started, does not require any user interaction. To demonstrate the capability of the automated system for patterning, electrochromic thin film devices using 50-bilayer laser patterned films using the polymers poly(allylamine hydrochloride) and sodium poly[2-(3-thienyl)-ethoxy-4-butylsulfonate] are presented. One device is patterned with the shape of a large "C," created by irradiating the sample (55 mW average power, 405nm) while the substrate was moved vertically up and down or the laser was moved horizontally. The laser irradiates the sample during only the dipping in the polycation polymer solution. A second electrochromic thin film device is based on a sample with five parallel laser patterned lines, where each line is fabricated with different average laser powers and, hence, different thicknesses. The thicknesses of the lines vary by about 30nm.

Utilising Response Surface Methodology to Optimise Food Additives and Treatments Reduces Disease Caused by Penicillium digitatum and Penicillium italicum in ‘Valencia’ Oranges

Penicillium digitatum and Penicillium italicum are responsible for citrus green and blue moulds (GM and BM), respectively, which are major citrus postharvest diseases. The aim of this study was to develop an optimal dipping mixture of an aqueous solution of different food additives: sodium bicarbonate (SB), sodium benzoate (SBen), and potassium sorbate (PS), in combination with heat, to control GM and BM using response surface methodology. The ranges of SB (0.0%, 3.0%, 6.0%), SBen (0.0%, 0.5%, 1.0%), PS (0.0%, 0.5%, 1.0%) and temperature (20 °C, 35 °C, 50 °C) with a dipping time of 60s were tested for their impact on GM and BM on artificially inoculated oranges. Within these tested ranges, SB reduced GM severity and incidences of both GM and BM. PS affected BM severity and incidence, but not GM. SBen and temperature did not have impact on GM and BM. The most suitable food additive concentrations were identified to be 4.7% SB, 1.0% SBen and 0.7% PS, with a dipping solution temperature of 50 °C. This treatment was shown to reduce GM and BM incidence from 85 and 86% on control fruit dipped in tap water at 20 °C to 3 and 10%, respectively. Additionally, the severity of GM and BM was reduced from 64 and 26 mm on control fruit to &lt;1 and 2.8 mm, respectively.

Risk factors contributing to tick-acaricide control failure in communal areas of the Oliver Tambo district eastern cape province, South Africa

Application of chemical acaricides in the control of ticks has led to the problem of tick-acaricide control failure. To obtain an understanding of the possible risk factors involved in this tick-acaricide control failure, this study investigated tick control practices on communal farms in the north-eastern part of the Eastern Cape Province (ECP) of South Africa. A semi-structured questionnaire designed to document specific farm attributes and acaricide usage practices was administered at 94 communal farms from the Oliver Tambo District municipality of the ECP. Data collected indicated that the main acaricide chemicals used at plunge dips of inland and coastal areas were synthetic pyrethroid formulations. Most (75%) farmers claimed not to have noticed a significant reduction in numbers of actively feeding and growing ticks on cattle after several acaricide treatments. Based on the farmers’ perceptions, leading factors that could have led to tick-acaricide control failure included: weak strength of the dip solution (76%); poor structural state of dip tanks (42%); and irregular tick control (21%). The rearing of crossbreeds of local and exotic cattle breeds, perceived weak strength of the dip solution and high frequency of acaricide treatment, were statistically associated with proportions of farms reporting tick-acaricide control failure. Furthermore, approximately 50% of farms reported at least four tick control malpractices, which could have resulted in the emergence and spread of tick-acaricide control failure. Other sub-optimal tick control practices encountered included incorrect acaricide rotation, and failure to treat all cattle in a herd. This data will inform and guide the development of management strategies for tick-acaricide control failure and resistance in communal farming areas.

Optical pH Sensor Based on a Long-Period Fiber Grating Coated with a Polymeric Layer-by-Layer Electrostatic Self-Assembled Nanofilm.

An optical fiber pH sensor based on a long-period fiber grating (LPFG) is reported. Two oppositely charged polymers, polyethylenimine (PEI) and polyacrylic acid (PAA), were alternately deposited on the sensing structure through a layer-by-layer (LbL) electrostatic self-assembly technique. Since the polymers are pH sensitive, their refractive index (RI) varies when the pH of the solution changes due to swelling/deswelling phenomena. The fabricated multilayer coating retained a similar property, enabling its use in pH-sensing applications. The pH of the PAA dipping solution was tuned so that a coated LPFG achieved a pH sensitivity of (6.3 ± 0.2) nm/pH in the 5.92-9.23 pH range. Only two bilayers of PEI/PAA were used as an overlay, which reduces the fabrication time and increases the reproducibility of the sensor, and its reversibility and repeatability were demonstrated by tracking the resonance band position throughout multiple cycles between different pH solutions. With simulation work and experimental results from a low-finesse Fabry-Perot (FP) cavity on a fiber tip, the coating properties were estimated. When saturated at low pH, it has a thickness of 200 nm and 1.53 ± 0.01 RI, expanding up to 310 nm with a 1.35 ± 0.01 RI at higher pH values, mostly due to the structural changes in the PAA.

Effects of Post-Harvest Processing Methods on the Quality of Radix et Rhizoma Salviae Miltiorrhizae

The effect of pretreatment, drying and storage methods on maintaining the quality of Radix et Rhizoma Salviae mitiorrhzae postharvest was studied. The experiments used organic acids as acid citric and sodium bisulfate solution to evaluate the pretreatment of Radix et Rhizoma Salviae mitiorrhzae. Rhizome and roots of Salvia miltiorrhiza Bunge were pretreated and dried by convection drier and heat pump drier and were preserved by low pressure. The results showed that dipping acid citric solution pH 2.5-3 for 30 minutes restricted the developing of total microorganisms. Using heat pump drier were good sensory quality and retaining tanshinone IIA, salvianolic acid content in Radix et Rhizoma Salviae mitiorrhzae. The method of preserving Radix et Rhizoma Salviae mitiorrhzae by the low pressure 200 mmHg, and 400 mmHg after 9 months at ambient temperature (25-30 oC), humidity (80-85%) maintained better quality than the control. Beside, the moisture&amp;rsquo;s medicine, tanshinone IIA, salvianolic acid content, and total microorganisms in the experiment samples changed slowly during the storage period.

Rhamnolipids‐based glycosylated coating for preparing non‐charging polymeric materials surfaces

AbstractPolymer materials are typical insulators that are easily charged by contact electrification. Static charge generated by contact electrification on their surfaces can lead to lots of undesirable consequences, including a reduction in efficiency of manufacturing processes, damage to equipment, and even explosions. Thus, it is important to develop effective strategies to prevent the generation of static charge when surfaces of polymer materials come into contact. Here, we coated polymer materials with rhamnolipids (RLs) to create non‐charging surfaces. This innovative technique, based on glycosylated coatings using RLs, offers a universal solution that can be easily applied to a wide range of polymeric materials conferring resistance to surface charging via contact electrification. The amount of static charges generated was found to reduce dramatically in both low (~15%) and high (~60%) humidity situations. The reduction of charge is due to either or both of the following two mechanisms: by increasing surface conductivity driven by the hydrophilic groups of the RLs molecules, and or by their radical‐scavenging properties. Predictably, this new effective strategy is ideal for producing antistatic dipping and spray solution for various practical applications.

The influence of pretreatments on the quality characteristics and in vitro biological activity of freeze-dried Thai Tom-Yum ingredients

This study aimed to investigate the effects of pretreatments on quality characteristics, bioaccessibility of phenolic compounds, and antioxidant activities (AA) of freeze-dried Thai Tom-Yum ingredients during in vitro digestion. Hot water (B), steam (S), microwave blanching (MW), ultrasound (US), and blanching with dipping in chemical solution (D) were performed on lemongrass, red onion, kaffir lime leaves, chili, galangal, and coriander. In most samples, D significantly lowered water activity (Aw) and moisture content (MC) while preserving color attributes. D was the best pretreatment with the highest total phenolic compounds (TPC) for lemongrass, red onion, and galangal, US for kaffir lime leaves and chili, and S for coriander. The AA assessed by DPPH and FRAP showed a correlation with TPC values (0.731 and 0.576 at p < 0.01). Bioaccessibility of phenolic compounds and FRAP in selected herbs were higher under intestinal phase. After digestion, kaffir lime leaves treated with US had the highest TPC and FRAP values, ranging from 26.63 to 34.34 mg GAE/g db and 80.07–105.07 μmol FeSO4/g db, respectively. A decrease in DPPH values was observed in lemongrass, red onion, chili, and galangal. These findings show that pretreatments and freeze-drying have considerable effects on the qualitative attributes, bioaccessibility of phenolic compounds, and AA of dried herbs.

A new universal detection system for high-performance thin-layer chromatography plates using chemiluminescence

High-performance thin-layer chromatography (HPTLC) is a cost-effective method for the separation of small molecules, such as active pharmaceutically ingredients. The method can be used without sophisticated equipment. For example, the detection and quantification of colored compounds on an HPTLC plate can be performed with a CCD camera. For noncolored compounds, a new dipping solution for the generation of chemiluminescence on an HPTLC plates is presented. In combination with a charge-coupled diode (CCD) camera, this can be used as a universal detection system. The efficiency of this new staining reagent is demonstrated by the detection of trimethoprim and sulfamethoxazole from a fixed-dose combination in a ratio of 1:5.

Effects of ascorbic acid and kelulut honey as antibrowning agent on the quality of minimally processed jackfruit (Artocarpus heterophyllus)

Minimally processed jackfruit is gaining popularity for its economic importance to the fruit industry, but its high susceptibility to enzymatic browning has been its limitation. This study determines the effects of applying ascorbic acid (AA) and kelulut honey (KH) on the shelf life of minimally processed jackfruit (MPJ) stored at chill and ambient temperature for 12 days. The quality of treated and untreated minimally processed jackfruit was evaluated by weight loss, firmness, colour (L* and b*), ascorbic acid content and browning inhibition. A microbiological analysis was performed to estimate the shelf-life. The MPJs dipped in 3% ascorbic acid and 3% kelulut honey and stored at 4°C showed the least weight loss of 0.75% and 0.42%, respectively, and the significantly least reduction in firmness of 67.93% and 65.24%, respectively. Ascorbic acid was found to be more efficient in reducing the discolouration of MPJ compared to kelulut honey. Depending on the temperature, the 3% KH dipping solution is more efficient than ascorbic acid in inhibiting the browning activity of MPJ with an inhibition of 9.29%, retaining ascorbic acid content (16.45 mg/100 g) and inhibiting microbial growth (6.20 log CFU/g) of MPJ up to 9 days of storage.

Oxidative Stability of Side-Streams from Cod Filleting-Effect of Antioxidant Dipping and Low-Temperature Storage.

Currently, side-streams (e.g., head, backbone, tail, and intestines) generated in the fish processing industry often end up as low-value products for feed applications or even as waste. In order to upcycle such side-streams, they need to be preserved to avoid oxidative degradation of the lipids between the generation point and the valorization plant. In the cod filleting industry, three main solid side-streams: viscera, heads, and backbones, are obtained. Hence, this study aimed to identify the most efficient antioxidant for preserving the cod side-streams using a dipping-based strategy prior to pre-valorization storage at low temperatures (ice and frozen storage). The dipping solutions evaluated contained: (i) a lipophilic rosemary extract (0.05% and 0.2% in 0.9% NaCl), (ii) Duralox MANC (a mixture of rosemary extract, ascorbic acid, tocopherols, and citric acid; 2% in 0.9% NaCl), and (iii) NaCl (0.9%) w/w solution. One group was not dipped. No dipping and dipping in NaCl were included as controls. The results showed a positive effect of dipping with solutions containing antioxidants as measured by peroxide value (PV), TBA-reactive substances (TBARS), and sensory profiling, e.g., rancid odor. Moreover, the oxidative stability increased with decreased storage temperature. The cod side-streams were in general most efficiently preserved by Duralox MANC, followed by the lipophilic rosemary extract (0.2%), compared to no dipping and dipping in NaCl solution and the lower concentration of the lipophilic rosemary extract (0.05%). The efficiency of the antioxidant treatments was independent of the side-stream fraction and storage temperature. Thus, using antioxidant dipping combined with low temperature storage is an efficient preservation method for maintaining the quality of the lipids in cod solid side-streams during their pre-valorization storage.