Albumen pH Research Articles

English

In this study, chitosan-coatings were prepared with acetic, lactic, propionic, gallic and caffeic acids and used for coating chicken and quail eggs to understand their effect on the quality and shelf-life of chicken and quail eggs. Shelf-life study of (weight loss, Haugh unit, yolk index, albumen pH, mineral levels and shell breaking strength) the coating formulations were investigated for 4 weeks. All chitosan coated chicken and quail egg samples showed greater interior (weight loss, Haugh unit, yolk index, albumen pH) and exterior quality (shell breaking strength) than non-coated samples (p<0.05).   Key words: Chitosan, phenolic substances, chicken egg, quail egg, shelf-life.

Influence of edible oil coating on internal quality characteristics and shelf life of chicken eggs stored at room temperature

Freshness is a foremost contribution to the egg quality. The present study was conducted to find out the edible oil coatings on physico-functional properties and internal egg quality of chicken eggs during storage at room temperature in Sri Lanka. 300 eggs were randomly divided into five treatments were defined with three replications viz. ; Sesame oil coted eggs (T1), coconut oil coated eggs (T2), olive oil coated eggs (T3), mustard oil coated eggs (T4), and uncoated eggs (T5). Eggs weight loss (%), Haugh Unit (HU), Yolk index (YI), Albumen pH, Yolk pH and Air Cell depth were determined. The data were analyzed using Complete Randomized Design by making use of Statistical Analysis System (SAS 9. 4) and the Least S results proved that, olive oil coated eggs significantly maintained a lower Weight loss (%), lower albumen pH, lowest yolk pH and maintained a higher Yolk Index (%), highest Haugh Unit during the storage time at 32 °C than followed by T1, T2and T4. Uncoated eggs show significantly lower internal quality than other treatments. Therefore, it could be concluded that olive oil edible coating is most suitable to preserve eggs and extending the shelf life of eggs in Sri Lanka.

Potential Implications of Natural Antioxidants of Plant Origin on Oxidative Stability of Chicken Albumen during Storage: A Review.

Enhanced albumen quality is reflected in increased thick albumen height, albumen weight, and Haugh unit value, while the antimicrobial, antioxidant, foaming, gelling, viscosity, and elasticity attributes are retained. Improved albumen quality is of benefit to consumers and to the food and health industries. Egg quality often declines during storage because eggs are highly perishable products and are most often not consumed immediately after oviposition. This review provides insights into albumen quality in terms of changes in albumen structure during storage, the influence of storage time and temperature, and the mitigation effects of natural dietary antioxidants of plant origin. During storage, albumen undergoes various physiochemical changes: loss of moisture and gaseous products through the shell pores and breakdown of carbonic acid, which induces albumen pH increases. High albumen pH acts as a catalyst for structural changes in albumen, including degradation of the β-ovomucin subunit and O-glycosidic bonds, collapse of the ovomucin-lysozyme complex, and decline in albumen protein–protein interactions. These culminate in declined albumen quality, characterized by the loss of albumen proteins, such as ovomucin, destabilized foaming and gelling capacity, decreased antimicrobial activity, albumen liquefaction, and reduced viscosity and elasticity. These changes and rates of albumen decline are more conspicuous at ambient temperature compared to low temperatures. Thus, albumen of poor quality due to the loss of functional and biological properties cannot be harnessed as a functional food, as an ingredient in food processing industries, and for its active compounds for drug creation in the health industry. The use of refrigerators, coatings, and thermal and non-thermal treatments to preserve albumen quality during storage are limited by huge financial costs, the skilled operations required, environmental pollution, and residue and toxicity effects. Nutritional interventions, including supplementation with natural antioxidants of plant origin in the diets of laying hens, have a promising potential as natural shelf-life extenders. Since they are safe, without residue effects, the bioactive compounds could be transferred to the egg. Natural antioxidants of plant origin have been found to increase albumen radical scavenging activity, increase the total antioxidant capacity of albumen, reduce the protein carbonyl and malondialdehyde (MDA) content of albumen, and prevent oxidative damage to the magnum, thereby eliminating the transfer of toxins to the egg. These products are targeted towards attenuating oxidative species and inhibiting or slowing down the rates of lipid and protein peroxidation, thereby enhancing egg quality and extending the shelf life of albumen.

Effects of Addition of TiO2 Edible Coatings and Storage Periods on the Chicken Eggs Quality

The study aims to determine the effect of addition TiO2 solution on edible coatings of nanocomposite casein-chitosan on the internal chicken eggs quality observed at 7 and 14 days of storage. The design of the study was a Complete Randomized Factorial Design using 2 factors and the length of storage of chicken eggs. The data was analyzed using the Analysis of Variance (ANOVA) and continued with Duncan's Multiple Range Test if there is a significant difference. Edible coatings made from casein-chitosan with the difference between addition of 3, 5, 10 mL of TiO2 1% then applicated of the solution as coating on eggs. The egg stored at 25 ℃ for 7 and 14 days then observed in the study i.e yolk index, albumen index, Haugh Unit, yolk color, yolk pH, albumen pH, and Total Plate Count (TPC). The results showed that the yolk index ranged from 0.25-0.40; albumen index 0.03-0.08; Haugh unit 48.68-80.42; yolk color 7-9; pH yolk 8.17-9.20; pH Albumen 8.17-9.20; TPC 0.7×105-1.1×105 cfu/mL. Edible coatings of casein-chitosan with 5 mL TiO2 solution were able to reduce the decrease in the internal quality of chicken eggs observed at 7 to 14 days of storage. However, all treatments in this study showed better results in the 7 days storage period.

Effects of Marketing Channels and Season on Weight and Quality Grades Classification According to Gulf Cooperation Council Standardization Organization standard of Fresh Commercial Table Eggs Marketed in Riyadh City (Saudi Arabia)

The present study aimed to assess egg quality by identifying quality grades and weight class classification of fresh commercial Table eggs marketed in the city of Riyadh during winter and the summer seasons, and comparing the measured traits rendering to the Gulf Cooperation Council Standardization Organization. A total of 480 eggs were purchased from two different channels of marketing, four supermarkets and four grocery stores located in different areas of the city of Riyadh during summer and the winter seasons. It appeared from the outcomes that the eggs purchased from the supermarkets had significantly higher AA and A Haugh units, albumin pH and AA air cell grades and medium egg weight class, and they also had lower B and C Haugh units, albumen pH, A and B air cell depth grades, and very large, large and small eggs weight classes percentages than those obtained from grocery stores. Over and above, the eggs obtained in the winter had significantly higher AA and A Haugh unit, albumin pH, AA air cell depth grades percentages, very large and large egg weight class percentages, and had less B and C Haugh unit and albumen pH and B air cell depth grades and small weight class percentages than those obtained in the summer. In summary, marketing channels and season play a significant role in affecting quality traits of Table eggs, also those procured from supermarkets and in the winter presented better quality than those obtained from groceries or in the summer, respectively. Grocery stores or small shops have to follow proper handling and storage conditions requirements to maintain good quality of Table eggs, especially in the summer season.

Quality of free-range and commercial eggs subjected to different storage periods and temperatures

Abstract The objective was to evaluate the internal quality of eggs from commercial laying hens and free-range hens subjected to different storage periods and temperatures. For the experiment, 280 eggs were randomly distributed into different treatments, adopting a completely randomized design, in a 2 x 7 factorial arrangement of two temperatures, seven storage periods, totaling 14 treatments with 10 replications. The treatments consisted of two storage conditions: under refrigeration (6 ± 1.0ºC) and at room temperature (26.6 ± 1.0ºC). Eggs were analyzed for 30 days, with evaluations in different storage periods (0, 5, 10, 15, 20, 25 and 30 days). For each storage condition, 140 eggs were separated, 70 commercial eggs and 70 free-range eggs. There was a linear increase in egg weight loss, yolk weight, albumen pH, yolk pH, length and width of albumen and yolk of commercial and free-range eggs, as the storage period increased. There was a linear reduction in weight, height and albumen index and in the yolk index of commercial and free-range eggs as the storage period increased, with more pronounced responses for eggs stored at room temperature (P<0.05). Albumen percentage was linearly reduced only for commercial eggs (P<0.05). Eggs kept at room temperature reduce their quality after 15 days of storage, and the storage under refrigeration for 30 days is recommended to preserve the shelf life of the egg for consumption.

Influences of Egg Washing and Storage Temperature on Quality and Shelf Life of Duck Eggs During Storage

Studies on how washing and storage influence duck egg quality are scarce compared with those on chicken egg quality. The present study investigated the quality of washed and unwashed duck eggs stored at 7 ºC and 25 ºC for 8 weeks. Quality parameters, including Haugh unit (HU), yolk index, thick albumen ratio, albumen pH, and air cell size, indicated that egg quality deteriorated during prolonged storage, and cuticle staining confirmed that washing reduced cuticle coverage. Washed eggs stored at 7 ºC maintained high quality (grade B; HU: 54) according to the United States Department of Agriculture (USDA, 2000) after storage for 8 weeks, whereas unwashed eggs stored at 25 ºC exhibited a low but acceptable quality (grade B, but HU: 36) after 7 weeks. Strong correlations were observed between the quality parameters evaluated. In conclusion, duck eggs should be washed and then stored at 7 ºC to enhance microbial safety and maintain quality to achieve a shelf life of at least 8 weeks.

THE PROFILE OF FATTY ACIDS AND THE EGGS QUALITY FROM HENS FED TO THE DIET WITH FLAX SEEDS, RAPESEED MEAL AND VITAMIN E SUPPLEMENTS

This experiment investigates the effect of flaxseed meal, rapeseed meal and vitamin E supplementation, when used together, on the production parameters of fatty acid composition and eggs quality characteristics in Tetra SL laying hens (38 to 46 weeks of age). For this, 120 hens were allocated one of three treatments, with 40 hens in each group. The hens were fed either a control diet (C), a control diet including 2.5 % flaxseed meal and 2.5% rapeseed meal (E1) or 2.5% flaxseed meal and 2.5% rapeseed meal with 73 mg/ kg feed of vitamin E as an antioxidant supplement (E2) for 8 weeks. Hens consuming the E1 diet had greater egg production and egg mass than those from group C. The feed conversion ratio in both the E1 and E2 groups was lower (P < 0.05) than in the C diet group. E2 had considerably higher egg weight, albumen pH, yolk pH and Haugh unit than E1 and C (P0.05), as a response to the vitamin E antioxidant effect. The most α-linolenic fatty acid content (1.07 g FAME) was found in eggs produced by chickens fed the E2 diet, (1.07 g FAME), followed by E1 (0.91 g FAME), with both being significantly higher than C eggs (0.23g FAME). Furthermore, all n-6 studied fatty acids concentrations were significantly lower (P < 0.05) in E1 and E2, while all n-3 fatty acids concentrations were significantly greater (P > 0.05) in E1 and E2. When comparing the n-6/n-3 ratio of fatty acids from experimental treatments (6.44 and 6.74) with C treatment (18.19), a significant difference was observed (almost 65% lower).

The Effect of Storage Duration on Some Quality Traits and Composition of Eggs from Different Housing Systems

Abstract The effect of storage time at a temperature of 8°C on the direction and dynamics of changes in quality traits of eggs was investigated in shelled table eggs obtained from different egg production systems (cage system – CS, barn system – BS, free-range system – FRS). After 7, 14 and 28 d of storage, eggs from each housing system were tested for physical characteristics and for cholesterol content and fatty acid profile in the yolk. The weight of eggs from all studied housing systems declined with storage duration. The rate of weight loss was smallest in eggs from CS (P<0.05). Storage duration influenced eggshell traits but the rate and direction of these changes did not differ among the studied housing systems. Albumen height and Haugh unit score for eggs from rearing systems under study declined during storage (P<0.05). The greatest reduction of albumen height (18.85%) after the storage period was observed for CS eggs and the lowest (13.24%) for FRS eggs (P<0.05). No effect of storage duration on yolk colour intensity was observed for eggs from all the studied housing systems (P>0.05). Albumen pH increased with storage duration in eggs from all the egg production systems (P<0.05). The increase in the yolk pH during storage was the highest in FRS eggs and the lowest in the CS eggs. The storage duration of eggs from the different housing systems did not significantly influence albumen foaming capacity but adversely affected foam stability. There was no impact of storage duration of eggs from different housing systems on cholesterol content in the yolk. Eggs obtained from the different housing systems showed diverse fatty acid profiles in the yolk but this parameter did not significantly change during storage (P>0.05).

EXTENDING POULTRY EGGS SHELF LIFE USING ETHNO BOTANICALS IN JOS PLATEAU STATE NIGERIA

Egg shelf-life extension is vital to minimizing egg waste especially during egg glut. In this research, ethanolic extracts from three ethno botanical plants –Eucalyptus torelliana (ET), Tamarindus indica (TI) and Anarcadium occidentals (AO) were used to coat poultry eggs to extend the egg shelf-life. All eggs both coated and uncoated were stored for ten weeks at an average temperature of 20+2oC and Humidity77+3%. The Haugh unit, weight loss, albumen pH, yolk lipid peroxidation, yolk index and yolk pH were measured every three days to monitor the deterioration of the eggs. Results reveal reduction in weight loss for AO 12%, TI 46% and ET 4%. No statistically significant difference in weight loss as compared to the control was observed for AO an ET coated eggs as p values were 0.9901 and 0.9808 respectively while TI had statistically significant weight loss reduction with p value (0.031); TI also demonstrated potency in maintaining yolk integrity of the eggs and minimized change in pH of egg albumen up to the seventh week of storage. Eggs coated with ET and AO were similar to the uncoated eggs in yolk pH, albumen pH, yolk index and Haugh unit. (TI) also demonstrated potency in minimizing egg yolk lipid peroxidation with lower malondialdehyde (MDA) levels as compared to all groups of eggs.

Obtaining of Chickpea Protein Isolate and its Application as Coating Enriched with Essential Oils from Satureja Hortensis and Satureja Mutica in Egg at Room Temperature

SummaryEggs are one of the most nutritious products on a daily basis. The objective of present research is to investigate the impact of coatings on improving storage time and internal quality of eggs. Coating treatments included control (C), coated with chickpea protein isolate (CPI), coated with PI containing Satureja hortensis (CPISH), coated with PI containing Satureja mutica (CPISM). Internal quality was assessed by air cell depth, shell strength, weight loss, haugh unit, yolk and albumen pH, yolk index, microbial evaluation and scanning electron microscope. The weight loss increased during storage and its highest value was 6.12%. Edible coatings (CPI, CPISH, CPISM) preserved internal quality according to the haugh unit, yolk index and pH over 4 weeks (20 °C) compared with C. Haugh unit (5.04), yolk index (0.31), albumen (9.51) and yolk pH (7.04) were detected in C after 7 weeks. CPISH and CPISM protected shell is observed by scanning electron microscope and these coatings affected the internal quality and were appropriate alternatives to extend storage.

The combined effect of green tea and peppermint oil against pathogenic bacteria to extend the shelf life of eggs at ambient temperature and the mode of action

AbstractThis work investigated the antimicrobial activities of green tea (GT) at 5 and 10.0% wt/vol and peppermint oil (PP) at 0.1, 0.15, and 0.2% wt/vol against major pathogen bacteria (Escherichia coli, Salmonella enteritidis, and Staphylococcus aureus) found on eggs at room temperature (30°C). The quality factors (weight loss, Haugh unit, albumen pH, egg yolk, and albumen index) of treated eggs were also measured while they were stored at room temperature for 14 days. A 9‐point hedonic scale was used for sensory evaluation. Scanning electron microscopy was used to examine the morphology of bacteria cells to understand this study's mechanism of action. It was found that combining 10% GT and 0.15% PP had complete antibacterial activity against all pathogenic bacteria investigated, and could extend the shelf life of treated eggs from 7 days (control) to at least 14 days. The treated egg's coliforms (≤3.0 log10 colony‐forming unit [CFU] g−1), E. coli (≤1.8 log10 CFU g−1), TVC (≤4.3 log10 CFU g−1), Salmonella spp., (not detected in 25 g), and S. aureus (not detected in 25 g) were better able to meet the microbiological criteria for egg after 14 days of storage, when compared to the control, which exceeded the criteria within 7 days. In addition, consumers rated egg acceptability as favorable by giving a sensory score ranging from like slightly to like moderately (~6.7). Furthermore, when compared to the control (6–7 days), all treated eggs retained their quality during storage for 14 days and met the microbiological criteria for egg in food standard (<4.7–6.0 log10 CFU g−1 for total visible count). Compound leakage from within the bacteria, which was the mode of action when GT and PP were combined, resulted in a wrinkled appearance of bacteria cells and serious defects in bacteria membrane morphology. These findings suggest that a sanitizing spray derived from GT and PP can extend the shelf life of eggs and ensure their safety for human consumption at room temperature without using a refrigerator.

Inactivation of Salmonella enterica Serovar Enteritidis on Chicken Eggshells Using Blue Light

Salmonella enterica serovar Enteritidis (S. Enteritidis) is a pathogen that poses a health risk. Blue light (BL), an emerging sanitization technology, was employed for the first time in the present study to inactivate S. Enteritidis on eggshell surfaces and its influence on maintaining eggshell freshness was investigated systematically. The results showed that 415 nm-BL irradiation at a dose of 360 J/cm2 reduced 5.19 log CFU/mL of S. Enteritidis in vitro. The test on eggshells inoculated with S. Enteritidis showed that a BL dose at 54.6 J/cm2 caused a 3.73 log CFU reduction per eggshell surface and the impact of BL inactivation could be sustained in post-5-week storage. The quality of the tested eggs (weight loss, yolk index, Haugh unit (HU) and albumen pH) demonstrated that BL treatments had negligible effects on the albumen pH of eggs. However, compared to the control, BL-treated eggs showed lower weight loss and higher HU after 5 weeks of storage at 25 °C and 65% humidity and yolk index in the control group could not be determined after 5 weeks of storage. Besides, the total amino acid content of the BL-treated egg was higher than the control, exhibiting an advantage of BL irradiation in maintaining the nutrient quality of whole eggs. The current study determined the efficacy of BL against S. Enteritidis on eggshell and suggested that BL could be an effective application in maintaining the freshness and quality of eggs.

SURVIVAL AND PROLIFERATION OF CAMPYLOBACTER IN ALBUMEN, YOLK, AND SHELL MEMBRANES OF BROILER BREEDER HATCHING EGGS

Fertile eggs were collected from 47-week-old broiler breeder hens, brought to the laboratory, and separated in 3 segments: albumen, yolk and membranes. Membranes were peeled away from the shell and wiped with 10.0 mL of buffered peptone. Initial pH of albumen and yolk was determined, but no pH was determined for the membranes due to settling of the membrane to the bottom of the tube. Then each segment was stored under refrigeration (4°C), at room temperature (22°C) and in an incubator (37°C) for 2 and 7 d with pH's taken at each time interval. Five replications (individual eggs) were taken. In addition, an inoculum of 3.4 A— 102/mL of a gentamicin-resistant Campylobacter coli was added to each segment of the egg and incubated at 22°C for 3 h; then C. coli was enumerated. Three full replications were conducted. Initial pH was 8.7 and 6.1 for the albumen and yolk. After 48 h at 4°C, 22°C and 37°C, the pH of the albumen, yolk and membrane were 9.0, 9.2, 9.4; 6.3, 7.1, 7.2; 8.2, 8.6, 8.4, respectively. When 2.53 log10 of C. coli was inoculated into albumen, yolk and membrane, the numbers increased in all 3 and were log10 3.0, 2.94, and 2.82, respectively. This demonstrates that Campylobacter not only survives in the different portions of the fertile egg but multiplies slightly, thereby strengthening the argument that Campylobacter may pass from one generation to the next via the fertile egg.Fertile eggs were collected from 47-week-old broiler breeder hens, brought to the laboratory, and separated in 3 segments: albumen, yolk and membranes. Membranes were peeled away from the shell and wiped with 10.0 mL of buffered peptone. Initial pH of albumen and yolk was determined, but no pH was determined for the membranes due to settling of the membrane to the bottom of the tube. Then each segment was stored under refrigeration (4°C), at room temperature (22°C) and in an incubator (37°C) for 2 and 7 d with pH's taken at each time interval. Five replications (individual eggs) were taken. In addition, an inoculum of 3.4 A— 102/mL of a gentamicin-resistant Campylobacter coli was added to each segment of the egg and incubated at 22°C for 3 h; then C. coli was enumerated. Three full replications were conducted. Initial pH was 8.7 and 6.1 for the albumen and yolk. After 48 h at 4°C, 22°C and 37°C, the pH of the albumen, yolk and membrane were 9.0, 9.2, 9.4; 6.3, 7.1, 7.2; 8.2, 8.6, 8.4, respectively. When 2.53 log10 of C. coli was inoculated into albumen, yolk and membrane, the numbers increased in all 3 and were log10 3.0, 2.94, and 2.82, respectively. This demonstrates that Campylobacter not only survives in the different portions of the fertile egg but multiplies slightly, thereby strengthening the argument that Campylobacter may pass from one generation to the next via the fertile egg.

Surface decontamination of whole eggs using pulsed light technology and shelf life study of combined pulsed light and vaseline coating during room temperature storage

It has been proved that pulsed light (PL) technology could effectively inactivate bacteria on egg surface. However, shelf life research on eggs after PL inactivation was limited. In this study, the decontamination effect of PL and interior quality of eggs during storage were investigated. In the decontamination study, shell eggs were inoculated with Escherichia coli ATCC 8879 strain and treated by PL for different intensities and pulse numbers. In the shelf life study, the non-inoculated eggs were treated by 4 procedures: untreated, PL treated, washing + vaseline coating and PL + vaseline coating. The interior qualities of the eggs were evaluated every week during storage at 25 °C for 6 weeks. The results revealed that maximum of 3.77 log CFU/egg of E. coli inactivation was achieved at PL fluence of 1.32 J/cm2 without causing significant effect (P > 0.05) on the temperature of the eggs. As storage time increased, the overall Haugh unit value and yolk index decreased, the albumen pH and weight loss increased. PL didn't affect albumen quality and there were no significant differences (P > 0.05) between washing + coating and PL + coating in the interior quality of eggs. These results demonstrate that PL has promising potential for surface decontamination of whole shell eggs as a possible industrial application.

Effect of dietary pumpkin (Cucurbita moschata) seed meal on layer performance and egg quality characteristics.

ObjectiveThe objective of this study was to investigate the effect of dietary pumpkin (Cucurbita moschata) seed meal (PSM) on laying hens’ performance, quality, fatty acids, cholesterol, antioxidant compounds and shelf life of eggs.MethodsEighty Tetra SL laying hens, 50-week-old, were randomly divided into two equal groups, having 10 replicates with 4 birds in each. The control (CON) treatment was fed with basal diet, while experimental treatment was fed a diet with 9% PSM, for a 6 week period.ResultsDietary PSM significantly decreased average daily feed intake (p<0.05), with no significant effect on other performance parameters. The PSM, enriched the eggs with polyunsaturated fatty acids, especially α linolenic acid (0.33 vs 0.21 g/100 g) and linoleic acid (20.65 vs 18.37 g/100 g), whereas it reduced the amount of arachidonic acid with 3.91% and n−6/n−3 ratio in PSM eggs compared with CON. The inclusion of 9% PSM significantly (p<0.05) diminished the cholesterol concentration in yolk with 11.31% and in egg with 10.38%, in respect to the CON samples. The significantly (p<0.05) higher concentration of polyphenols and antioxidant compounds, determined in PSM eggs, proved to be effective on shelf life of eggs preserved at refrigerator (5°C) and room temperature (21°C) for 28 days, by delaying the lipid oxidation and protein denaturation. This effect was reflected in significantly (p<0.05) higher Haugh unit in eggs stored 28 days at 21°C and lower albumen pH values for the overall storage time, both at 5°C and 21°C, proving the antioxidant effect of pumpkin.ConclusionDietary PSM supplementation was significantly effective on average daily feed intake and egg quality by increasing some fatty acids while lowering the cholesterol concentration. Also, PSM proved to be effective improving shelf life of eggs for 28 days storage time.

Development of an innovative green coating to reduce egg losses

Coatings based on plant by-products can contribute to the enhancement of raw material by preparing value-added products. In addition, the extension of shelf-life of eggs contributes to the reduction of food losses and decreases the use of refrigeration, energy demand, production costs, and consequently avoid the increase in the price of the final product. The rice protein concentrate (RPC) and plus Brazilian green propolis (GP), were used in the manufacture of coatings used to extend the shelf-life of eggs during storage for 6 ​wk at 20 ​°C. In this regard, some quality parameters of eggs were analyzed in this research. The coatings based on RPC and GP delayed the loss of internal egg quality, since avoided moisture loss through the pores of the eggshell. The weight loss increased ( P ​< ​0.001) during storage and uncoated eggs had the worst weight loss (5.41%) after 6 ​wk of storage and coatings of RPC (4.25%) or GP (4.08%), and RPC ​+ ​GP (4.14%) solutions effectively reduced the weight lost ( P ​< ​0.001). In addition, uncoated eggs had the worst value of HU (58.54), albumen pH (9.51), and yolk index (YI 0.33) after storage ( P ​< ​0.001). Correlations were observed between the quality parameters evaluated. The improvement of the quality attributes showed the potential of using coatings, such as the RPC and GP coatings analyzed in this research. • Eggs stored at room temperature presents fast degradation. • Coatings offer protection, increase shelf-life, and reducing egg waste. • A new green coating for eggs was developed. • Rice protein and green propolis coating is a new method to extend shelf-life.

Egg characteristics of Japanese quail fed diets containing guava extract (Psidium guajava L.)

The main purpose of this study was to evaluate the characteristics of eggs produced by Japanese quails fed with guava extract. A total of 400 eggs collected from the quails fed with experimental diets, were distributed in a completely randomized design in factorial arrangement 4 x 4 with main effects including four dietary levels of guava extract (0, 3, 6 and 9 g kg-1) and four storage periods (0, 9, 18 and 27 days) totalizing 16 treatments with five replicates of five eggs. The eggs were produced by Japanese quails, fed with experimental diets. The diets were isonutritive formulated by corn-soybean basis. The eggs were stored for different periods, at the same conditions, to constitute the treatments. The parameters evaluated were egg weight loss (g and %), yolk color, Haugh unit, specific gravity, eggshell thickness and pH of the yolk and albumen. Data were submitted to ANOVA, and means were compared using Scott-Knott test, using α = 0.05. The specific gravity of fresh eggs was better with the use of 6 g kg-1 of guava extract in the diet. The use of 3 g kg-1 of guava extract resulted in smaller eggshell thickness of fresh eggs. The Haugh unit was affected just by the storage periods. The dietary guava extract (3, 6 or 9 g kg-1) increased the pH of albumen in eggs stored for 27 days. The use of 6 g kg-1 of guava extract in quails diet increase the specific gravity in fresh eggs and increase the yolk color when the eggs are stored.

Internal quality of commercial eggs stored under conditions that simulate storage from laying to consumption

This study evaluated the effects on the internal quality of eggs of various storage environments through which eggs may pass between being laid and being consumed. Commercial eggs (N = 648) from Dekalb White hens were used. Treatments consisted of T1: 28 days at 4 °C; T2: 28 days at 20 °C; T3: 7 days at room temperature (27 °C ± 2 °C) (humidity 55%) and 21 days at 4 °C; T4: 7 days at room temperature and 21 days at 20 °C; T5: 14 days at room temperature and 14 days at 4 °C; T6: 14 days at room temperature and 14 days at 20 °C; T7: 21 days at room temperature and 7 days at 4 °C; T8: 21 days at room temperature and 7 days at 20 °C; and T9: 28 days at room temperature. The characteristics that were evaluated consisted of Haugh unit (HU), yolk index (YI), colour (L*, a* and b*), albumen pH, yolk pH and lipid oxidation. Eggs stored 28 days were darker (L*), and had greater yolk pH and lipid oxidation than fresh eggs. Eggs stored under T1 and T3 conditions had greater HU and YI than eggs stored in the other environments. The albumin pH of eggs stored at room temperature (T9) was highest of the treatments. Yellowness was increased in eggs stored under T4, T6, T8, and T9 conditions. Eggs should be stored under refrigeration as this promotes maintenance of internal quality and mitigates negative effects of previous storage conditions.

Impact of Ginger Root Powder Dietary Supplement on Productive Performance, Egg Quality, Antioxidant Status and Blood Parameters in Laying Japanese Quails.

Medicinal plants with antibacterial effects have been used by humans for centuries. In the recent decade, due to the development of antibiotic resistant strains, many studies have focused on the use of natural compounds as feed additives in livestock. Ginger, among all, have repetitively shown numerous biological activities, antibacterial, and antibiotic properties. This study was conducted to evaluate the effects of ginger root powder (GP) on the performance, egg quality, and blood parameters of Japanese quail. A total of 240 10-weeks old female quails were used in a completely randomized design with 4 treatments, 4 replicates, and 15 birds per replicate. Dietary treatment were basal diet (control) and basal diet containing 0.5, 1, and 1.5 g/kg of ginger root powder. Growth performance and exterior and interior quality of egg were measured biweekly over eight-week period. At the end of experiment blood parameters were evaluated. The results showed that diet supplementation with different levels of GP had no significant effect on egg production, egg mass weight, and egg weight (p > 0.05). However, feed intake and feed conversion ratio were significantly lower in the treatment group than the control in the whole period (p < 0.05). Egg Quality traits (shape index, albumen index, the percentage of albumen, yolk and shell, yolk pH, and shell thickness and strength) were not affected by the supplements in the whole trial period. Addition of GP significantly increased the albumen height, Haugh unit, and albumen pH in comparison with the control treatment (p < 0.05). GP reduced blood triglyceride level yet was ineffective on blood total antioxidant capacity and malondialdehyde. In conclusion, dietary supplementation with GP, could improve productive performance and the egg quality of Japanese quails. Nonetheless a comprehensive study needs to be performed in order to evaluate the impact of quail dietary ginger supplementation on productive performance and egg quality and their stability during storage time for commercial use.