The shellac and shellac nanocomposite coatings on enhanced the storage stability of fresh eggs for sustainable packaging.

Shellac bio-coatings can enhance to improve quality and storage stability of fresh egg qualities with improved shell strength therefore minimizing the reduction the egg losses. Shellac bio-chitosan at 3 concentrations (1 %, 4 % and 8 % w/w) and shellac-1 % montmorillonite nanocomposites were applied as biocoatings to improve storage stability. Shellac-8 % (SH-8 %) coated eggs exhibited the lowest weight loss (1.28 %), significantly. The weight loss of shellac 1 % + MMT and 4 % shellac (SH-4 %) coated eggs was similar each other and had lower weight loss than 1 % shellac (SH-1 %). The Haugh Unit (HU) of eggs with SH-8 % (63.75) had the significantly the highest HU. The SH-4 % (60.24) and SH-1 %/MMT-1 % (58.04) were similar, and the control was the lowest one. The albumin pH of SH-8 % (9.15) coated exhibited a significantly lower than SH-4 % (9.21) and SH-1 %/MMT-1 % (9.24), while the control (9.39) was the highest value at end of storage. For the shellac coated group, total soluble values of albumen reached 12.87 (initial) to 16.331 (SH-1 %), 15.96 (SH-4 %), 15.60 (SH-8 %) and 16.15 (SH-%1-MMT-1 %) at the end of storage. The RWC and foam stability of SH-8 %, SH-4 % and SH-1 % MMT-1 % were similar and higher than 1 % SH and uncoated egg samples. The rheology behaviors were maintained with increasing shellac concentration through the storage. SH-8 % biocoatings were very most effective in filling and sealing the porous in the eggshell and protecting the storage stability and enhancing the strength of the eggshell. Shellac bio-coatings acted as a tiny layer for an effective protective barrier to gas permeability for enhancing the storage stability of the fresh eggs. Higher shellac concentrations (4 and 8 %) and 1 %-MMT were enhanced the storage stability and can be vital solutions for improving shell strength, so it decreases breakage rates.

Combined effect of electrolyzed water (EW) and sonication with equilibrium modified atmosphere packaging for prolonging storage stability of fresh strawberry.

This research focuses on the effectiveness of electrolyzed water (50 and 100 ppm for 3 min), ultrasonication (80 W for 3 min), and their combinations on fresh strawberries, which are then packaged using microperforated film to enhance their storage stability. The gas composition in the headspace, pH, soluble solids, color (L*, a*, b*, and ΔE* values), anthocyanins, total phenolics, and texture profile was evaluated for the 35 days of storage at +4 °C. The lowest weight loss was measured at about 100 ppm electrolyzed water (EW; 0.47%), and the highest one was in the control group (0.57%) after storage. At the end of the storage, O2 in the headspace decreased from 20.90% to 10.50-8.10% and CO2 was accumulated from 0.03% to 16.4-14.34%. The results showed that soluble solids decreased (9.95 to 8.48-7.85 °Bx) and pH values increased (3.34 to 3.79-3.91) during storage. At the end of the storage, the total phenolics in the control group decreased by the most during storage (from 1209.09 ppm to 808.00 ppm), whereas the 50 ppm EW group had the highest (931.66 ppm). Further, the significantly highest anthocyanin amount was found to be 143.86 ppm in the 100 ppm EW group at the end of 28 days of storage. The EW can significantly delay the degradation of anthocyanin over the storage period. The sonication at 100 ppm EW damages strawberry tissues, reducing their hardness. The lowest decay rate was found in fruits treated with 100 ppm EW (41.67%), followed by 50 ppm EW (58.33%), compared to the control (75.00%). This study reveals that applications of the 50 ppm EW and also 50 pm EW combined with ultrasonication have great potential in the extending storage stability of the fresh strawberries.

Disinfection of Clostridioides difficile on spinach with epigallocatechin-based antimicrobial solutions and sodium hypochlorite.

The removal of C. difficile inoculated on fresh spinach leaves washed with antimicrobial solutions was investigated. In addition, the effect of washing solutions on the total aerobic mesophilic bacteria (TAMB) and Enterobacteriaceae in the fresh spinach was examined. The fresh spinach was washed through immersion in different concentrations (MIC, 2xMIC, and 4xMIC) of the natural disinfectant solution (NDS) consisting of EDTA, borax, and epigallocatechin gallate (EGCG) content developed in our laboratory and green tea extract-acetic acid (GTE-AA) for varying contact times (5 and 15 min). Different concentrations (50, 100, and 200 ppm) of sodium hypochlorite (NaOCl) and tap water as the control group were used to compare the effectiveness of the NDS. In addition, the effects of washing on the color, texture, and total phenol content of the spinach were determined. No statistical difference was observed in the washing of the spinach leaves with NDS prepared at 2xMIC and 4xMIC concentrations, while inhibition of C. difficile ranged between 2.11 and 2.32 logs. The highest inhibition was observed in the application of 50 ppm NaOCl for 15 min with a decrease of 2.88 logs in C. difficile spores. The GTE-AA and NDS decreased the number of TAMB by 2.27-3.08 log and, 3.21-3.66 log, respectively. Washing spinach leaves with natural disinfectant for 5 min caused a decrease of 2.58 logs in Enterobacteriaceae load, while washing with 50 ppm NaOCl for 15 min reduced Enterobacteriaceae load by 4 logs. Tap water was ineffective in reducing any microbial load. No difference was detected in the color parameters of the spinach through all washes. Although all antimicrobial washes made a difference in the texture of the spinach, the greatest loss in firmness was observed in the spinach washed with NaOCl. Washing spinach with epigallocatechin-based wash solutions can remove C. difficile in possible C. difficile contamination, thereby reducing the environmental load of C. difficile. Epigallocatechin-based disinfectants can be an alternative to chlorine-based disinfectants in improving the microbial quality of vegetables.

Effectiveness of enzymes on structural, functional and creep-recovery behavior of freshly prepared meringue's batter using liquid egg albumen.

In this research, the impacts of varying concentration of phospholipase A2 (PLA), protease and lipase enzyme-treated liquid egg white (LEW) were prepared using meringue batters. The gelling physico-chemical, and rheological properties such as rheological creep-recovery compliance behavior, color value (L*, a*, b*, ∆E*, Chroma, Hue and WI), gelling strenght, pH value, gelling index as TPA parameter and specific density of freshly prepared meringue batter were analyzed. The specific density of meringue batter of control (0.49 ± 0.01) was significantly decreased (P < 0.05) after enzyme treatments of PLA (0.39 ± 0.01), lipase (0.33 ± 0.01), and protease (0.37 ± 0.01). Also, the enzymatic treatment significantly decreased the b* values from - 0.08 ± 0.07 to - 0.76 ± 0.04, - 0.70 ± 0.06, and - 0.73 ± 0.03, respectively. The Burgers model was used to characterize rheological behavior of enzyme treated and freshly prepared meringue samples. Creep-recovery responses of samples were satisfactory (R2 > 0.99) for evaluation of creep-recovery behavior. This research points out the efficacy of lipase pre-treated LEW in meringue preparation on improving functionality such as batter density and gelling properties.

Ozone treatment of shell eggs to preserve functional quality and enhance shelf life during storage.

BACKROUND: Eggs have long been recognised as a source of high-quality proteins. Many methods exist to extend shelf life of food and one of them is ozone treatment, which is an emerging technology for disinfecting surfaces in the food industry. This study aimed to extend the shelf life of fresh eggs using gaseous ozone treatments at concentrations of 2, 4 and 6 ppm with exposure times of 2 and 5 min during storage for 6 weeks at 24 °C. The effect of the treatments on interior quality and functional properties of eggs is also reported. RESULTS: Ozone concentration and exposure time significantly affected the Haugh unit (HU), yolk index, albumen pH, relative whipping capacity (RWC), and albumen viscosity of eggs during the storage. Control eggs had the highest albumen pH and lowest albumen viscosity. Attributes such as albumen pH and RWC of eggs exposed to ozone treatments were better than the control samples. The measurement results showed that ozone concentration at 6 ppm and exposure time of 5 min can be applied to fresh eggs and extend shelf life up to 6 weeks at 24 °C storage period. CONCLUSION: Ozone treatments helped to maintain egg quality for a longer time. Ozone concentrations at 2 and 4 ppm showed promising results in maintaining internal quality and functional properties of fresh eggs during storage. Ozone at high concentration (6 ppm) caused a detrimental effect on eggshell quality. As a result, this study demonstrated that ozone treatments of 2, and especially 4 and 6 ppm concentration maintained eggshell quality during the storage. © 2015 Society of Chemical Industry.

Efficacy of various protein-based coating on enhancing the shelf life of fresh eggs during storage.

The effectiveness of various coatings (whey protein isolate [WPI], whey protein concentrate [WPC], zein, and shellac) on functional properties, interior quality, and eggshell breaking strength of fresh eggs were evaluated during storage at 24 °: C for 6 weeks. Coatings and storage time had significant effects on Haugh unit, yolk index, albumen pH, dry matter (DMA), relative whipping capacity (RWC), and albumen viscosity. Uncoated eggs had higher albumen pH (9.56) and weight loss, and lower albumen viscosity (5.73), Haugh unit (HU), and yolk index (YI) during storage. Among the coated eggs, the shellac and zein coated eggs had the highest value of albumen viscosity (27.26 to 26.90), HU (74.10 to 73.61), and YI (44.84 to 44.63) after storage. Shellac (1.44%) was more effective in preventing weight loss than WPC (4.59%), WPI (4.60%), and zein (2.13%) coatings. Uncoated eggs had the higest value (6.71%) of weight lost. All coatings increased shell strength (5.18 to 5.73 for top and 3.58 to 4.71 for bottom) significantly (P < 0.05) compared to the uncoated eggs (4.70 for top and 3.15 for bottom). The functional properties such as albumen DMA (14.50 to 16.66 and 18.97 for uncoated) and albumen RWC (841 to 891 and 475 for uncoated) of fresh eggs can be preserved during storage when they are coated. The shellac and zein coatings were more effective for maintaining the internal quality of fresh eggs during storage. Fourier transform near infrared (FT-NIR) in the 800 to 2500 nm reflection spectra were used to quantify the contents of the fresh eggs at the end of storage. Eggs coated with shellac or zein displayed a higher absorbance at 970 and 1,197 nm respectively (OH vibration of water) compared with those coated with WPI or WPC and the uncoated group at the end of storage. The coatings improved functional properties and also shell strength and could be a viable alternative technology for maintaining the internal quality of eggs during long-term storage. This study highlights the promising use of various coatings to both enhance the functional properties and to reduce the breakage of eggs.

Maintaining functional properties of shell eggs by ultrasound treatment.

BACKROUND: Ultrasonic treatment is an emerging technique that could be an alternative to existing thermal processing techniques in foods. Ultrasonic treatments may also be used to extend the shelf life of egg during storage period in ambient temperature. The effectiveness of ultrasound treatment with different power levels (200 W, 300 W, 450 W) and treatment times (2 min and 5 min) was evaluated for enhancing the functional properties of eggs during storage at 24 ° C for 6 weeks. RESULTS: Ultrasound treatment power and treatment time had significant effects on Haugh unit, yolk index, albumen pH, dry matter, relative whipping capacity, and albumen viscosity resulting in extended shelf life. Attributes such as yolk index, Haugh unit, pH, whipping capacity, dry matter for 300 W and 450 W treatments were better than control and 200 W treatments. Longer treatment time and power showed a significant influence on functional properties. CONCLUSION: Power levels of 300 W and 450 W of ultrasound treatments had improved internal quality of fresh eggs during storage, but negative effect on shell strength. The study showed that ultrasound treatment could be an alternative and effective technique for maintaining the internal qualities of fresh eggs during long-term storage while Fourier transform near infrared spectroscopy could be used as a new tool for the assessment of freshness.

Antimicrobial lysozyme-chitosan coatings affect functional properties and shelf life of chicken eggs during storage.

BACKGROUND: The interior quality, shell impact strength and functional characteristics of eggs coated with chitosan and lysozyme-chitosan combinations were evaluated for enhancing egg freshness during storage. A 10% (w/w) lysozyme solution was incorporated into 1% (w/w) chitosan film-forming solution at ratios of 0, 10, 20 and 60% (w/w). RESULTS: Storage time and coating had significant effects on Haugh unit, yolk index, weight loss, albumen pH, dry matter, relative whipping capacity (RWC) and albumen viscosity. Uncoated eggs had higher albumen pH and weight loss and lower albumen viscosity. All coated eggshells showed greater puncture strength than uncoated eggshells, resulting in extended shelf life. The 20 and 60% lysozyme-chitosan coatings were more effective in maintaining the internal quality of eggs (e.g. pH, dry matter and RWC). Attributes such as pH, dry matter and RWC were better after the 20% lysozyme-chitosan treatment than after the other treatments. CONCLUSION: The 10, 20 and 60% lysozyme-chitosan coatings, considered active packaging, showed promising attributes. They could be a viable alternative to existing techniques for maintaining the internal quality of fresh eggs during long-term storage. Chitosan coatings also improved shell strength. This study also confirms that measurements of albumen quality (pH, dry matter, viscosity and RWC) are excellent indicators of egg freshness.

Effect of latanoprost/timolol and dorzolamide/tiomolol on intraocular pressure after phacoemulsification surgery.

AIM: To evalaute the effect of fixed-combination latanoprost 0.005%/timolol maleate 0.5% and dorzolamide hydrochloride 2%/timolol maleate 0.5% on postoperative intraocular pressure after phacoemulsification cataract surgery. METHODS: This study is a prospective, randomized, double-masked and placebo-controlled. The study included 90 eyes of 90 patients which were scheduled to have phacoemulsification surgery. Patients were randomly assigned preoperatively to 1 of 3 groups (30 eyes of 30 patients). Two hour before surgery, the patients received one drop latanoprost/timolol (group 1), dorzolamide/timolol (group 2) and placebo (group 3, control group). The IOPs were measured at preoperative and postoperative 4, 8, and 24 hours. RESULTS: The preoperative mean intraocular pressure was not statistically significant between both drug groups and control group. In group 1 and 2, the postoperative mean IOP [group1: (14.03±3.15)mmHg and group 2: (14.16±4.43)mmHg] at 24 hours were significantly lower than the control group [(16.93±3.70)mmHg, (P<0.05)]. In addition, the postoperative mean IOP of group 1 [(14.90±3.69)mmHg] at 8 hours was significantly lower than the control group [(17.70±3.89)mmHg, (P<0.05)], but there was no significant difference between group 2 [(16.16±5.23)mmHg] and control group at 8 hours (P>0.05). CONCLUSION: When compared with placebo, the use of preoperative fixed combination of latanoprost/timolol and dorzolamide/timolol is an effective method for preventing intraocular pressure elevation in 24 hours after phacoemulsification surgery, but did not completely prevent IOP spikes.