Abstract
In the United States, eggs from commercial table layers must be stored at a temperature no greater than 7°C after being packaged for consumer consumption. Understanding how the overall eggshell quality deteriorates during a 28-day storage period at 4°C is beneficial information to the commercial table industry. The objective of this study was to evaluate how a 28-day storage period at 4°C affects the translucency score (TS) and overall eggshell quality of table eggs from Hyline W-36 hens. This study was conducted with 521 eggs from 55-week-old Hyline W-36 laying hens. Eggs were collected on day 0 and washed before undergoing initial external eggshell quality parameter testing (TS, weights, and L* scores), and eggshell thickness measurements. Subsequent external quality parameter testing was conducted on days 7, 14, 21, and 28. Additional TS measurements were taken on day 1. Internal eggshell quality parameter testing (albumen height, Haugh units, yolk color, and egg grade) and breaking strength measurements were taken on days 1, 14 and 28. Data was analyzed using PROC Mixed with LSMeans when appropriate, PROC GLM with Tukey’s HSD when appropriate, or a Chi-Square analysis with P ≤ 0.05. Storage duration and TS had a significant interaction effect on albumen height and Haugh units (P < 0.0001 for both variables). Eggshell thickness was only influenced by TS (P = 0.0196) with TS 1 and 2 eggs having the thinnest shells (0.460 mm and 0.462, respectively) and TS 3 eggs having the thickest shells (0.472 mm). The storage period significantly affected egg weight, L* scores, TS, yolk color, and egg grade (P < 0.0001, P < 0.0001, P < 0.0001, P = 0.0450, and P = 0.0456, respectively). The results from this study are not conclusive on the use of TS as an effective parameter for determining eggshell quality during the storage period. However, it can be concluded that overall eggshell quality does deteriorate during a 28-day storage period at 4°C.
Keywords: Translucency score, Eggshell quality, Storage, Layer
Introduction
In the poultry industry, table eggs are stored from the day of collection until they are sold to consumers, which must not exceed 30 days (Department of Agriculture, Food Safety and Inspection Service 2025). Increasing the quality of these eggs throughout the storage period could decrease the wastage of eggs due to poor quality. The Egg Product Inspection Act requires eggs packaged for consumer consumption to be stored and transported at a temperature no greater than 7.2°C (Department of Agriculture, Agriculture Marketing Service 1998). A better understanding of how eggshell quality is affected at a normal refrigerated temperature (4°C) could benefit the commercial table egg industry.
In previous research, the use of different storage durations and temperatures and their effects on eggshell quality have been conducted. Eggs that were stored at a temperature of 14°C for 28 days were found to have a significantly lower egg weight at day 28 than at day 0 (Wengerska et al., 2023). This study also found that albumen height was significantly lower on day 28 than on day 0 and that yolk color was significantly higher on day 28 than on day 0 (Wengerska et al., 2023). Grashorn et al. (2016) found that there was a significant interaction between storage duration and storage temperature on air cell size, weight loss, and Haugh units. For all variables, 6°C showed the smallest decline in quality, with 15°C showing the largest decline. However, considering each factor alone, a significant effect on air cell size, weight loss, Haugh units, and eggshell thickness was only observed due to the storage duration (Grashorn et al., 2016). This finding shows the importance of utilizing the correct storage length to maximize overall egg quality. An older study completed by Jones and Musgrove (2005) examined the quality of eggs stored for up to 10 weeks at 4°C. They found that Haugh units were above the requirements for AA eggs until week 5. At week 6, Haugh units fell into the grade A requirements where they stayed until the end of the study at week 10.
Translucency was first reported by Holst et al. in 1932 and was described as moisture accumulation within the eggshell. Since its discovery, translucency score has been researched in both layer and broiler breeder hens to determine if it is linked to eggshell quality. It has been found that as bird age increases, there is an increase in the translucency score of their eggs (Roberts et al., 2013). However, there are conflicting results relating to the relationship between translucency score and eggshell quality measurements, with some studies finding that translucency score significantly increases the quality, and others finding no correlation (Holst et al., 1932; Talbot and Tyler, 1974; Wang et al., 2017; Ren et al., 2023; Xuan and Zheng, 2024).
To our knowledge, there has only been one study completed looking at the effect of the storage period and temperature on translucency score (Xuan and Zheng, 2024). In that study, they found that a higher storage temperature, regardless of storage duration, resulted in a greater translucency score. Talbot and Tyler (1974) discovered that translucency score was not a fixed parameter, and at the time of lay, no translucent areas were observed on the eggshell, but after 24 hours, the translucent areas became more visible. From these findings, we decided to explore the relationship between storage period, translucency score, and eggshell quality. We hypothesize that at a refrigerated temperature, overall eggshell quality and translucency score will decrease as the storage period increases.
Materials and methods
Eggs were collected from 55-week-old Hyline W-36 laying hens. All eggs were collected after a 22-hour laying period. Eggs that were free from visible malformations and cracks were utilized for this study, resulting in a total of 521 eggs. These eggs were then washed with municipal water using the Aquamagic (National Poultry Equipment Company, Marion, IA, USA) at the Poultry Research Farm at Mississippi State University. The clean eggs were then numbered sequentially (1-521). Eggs were then moved into an egg storage room with an average temperature of 4°C where they remained for up to 28 days.
External eggshell quality parameters
The parameters considered for external eggshell quality were egg weights, eggshell lightness (L* Scores; 0-100 scale, 0=black and 100=light), and TS. These parameters were taken on days 0, 7, 14, 21, and 28. L* scores were collected utilizing an electronic colorimeter (Nix Color Sensor, Nix Spectro L, Canada) and measurements were taken on the broad end of the eggshell. Translucency scores were measured using an eggshell candler and were scored on a scale of 1-3 (1: few to no translucent spots; 2: several and small translucent spots; 3: many and large translucent areas; Fig. 1; Holst et al., 1932; Baker and Curtiss, 1958; Orellana et al., 2023; Kroetz Neto et al., 2024). On day 1, TS was measured again and 20 eggs/TS were utilized to undergo eggshell-breaking strength measurements. Subsequent eggshell-breaking strength measurements were conducted on days 14 and 28. Eggshell breaking strength was tested using the Orka Eggshell Ultimate (Orka Food Technology, West Bountiful, UT, USA). Along with this, eggshell thickness measurements were taken on days 0 and 28 utilizing an ultrasonic eggshell thickness gauge (Orka Food Technology, Precision Ultrasonic Eggshell Thickness Gauge)
Fig. 1.
Example of eggs at each translucency score. A shows an egg with a translucency score of 1. B shows an egg with a translucency score of 2. C shows an egg with a translucency score of 3.
Internal eggshell quality parameters
The parameters considered for internal eggshell quality include Haugh unit, albumen height, egg grade, and yolk color. These parameters were measured on days 1, 14, and 28. Internal quality measurements were taken from the same 20 eggs/TS that were first utilized for breaking strength. All internal quality parameter measurements were collected using the Orka Eggshell Ultimate.
Statistical analysis
Statistical analyses for this study were performed utilizing SAS (Version 9.4, SAS Institute Inc., Cary, NC) with significance set at P ≤ 0.05. Eggs that were removed due to breakage or breaking strength/internal quality measurements were removed from the external quality analyses, resulting in a total number of 392 eggs being utilized for these measurements. Egg weights, thickness, L* scores and TS were analyzed using a PROC Mixed repeated measurements procedure with egg set as the random variable and TS, storage day and the interaction of the two as the fixed effects. Means from these analyses were separated using LSMeans when appropriate. A PROC GLM one-way ANOVA was used to analyze albumen height and Haugh unit, and where appropriate, Tukey’s HSD was utilized to separate means. A chi-square analysis was used to analyze yolk color and egg grade, and where appropriate a Kruskal Wallis test was used to separate means. For all analyses, eggs were pooled together by either storage duration or TS when looking at the main effects, and separated out by TS and storage duration when looking at the interaction between the two fixed effects.
Results
External eggshell quality
No significant interaction effects were observed for this experiment. Eggshell thickness was not significantly affected by the storage period (P = 0.552; Table 1). However, eggshell thickness was significantly affected by the translucency score, with TS 1 and 2 eggs having a lower eggshell thickness than TS 3 eggs (P = 0.020; Table 1).
Table 1.
Effects on thickness*.
| Storage*Translucency Interaction | |||
|---|---|---|---|
| Storage | TS⁎⁎ 1 | TS⁎⁎ 2 | TS⁎⁎ 3 |
| Day 0 | 0.460 | 0.468 | 0.475 |
| Day 28 | 0.455 | 0.459 | 0.470 |
| SEM | 0.0049 | ||
| P-Value | 0.859 | ||
| Storage | |||
|---|---|---|---|
| Day 0 | 0.464 | ||
| Day 28 | 0.462 | ||
| SEM | 0.0025 | ||
| P-Value | 0.552 | ||
– differences within a column are denoted by differing superscripts.
– Proc Mixed Procedure with egg as the random variable and TS, storage, and the interaction of the two as the fixed variable.
– Translucency score is denoted by TS.
– Eggs were pooled from all storage points to determine these values.
Storage period had a significant effect on egg weights (P < 0.0001; Table 2), L* scores (P < 0.0001; Table 2), and eggshell translucency (P < 0.0001; Table 2). Eggs on day 0 had a significantly higher egg weight than days 14, 21, and 28. L* score measurements significantly increased from day 0 to day 14, and then significantly decreased on day 21. This means that eggshells were becoming lighter from day 0 to day 14 and then became darker from day 14 to day 21. TS significantly increased as the storage period progressed, with day 0 having the lowest average TS and increasing until day 7 and resumed increasing from day 14 to day 28. The distribution of TS throughout the storage period is shown in Fig. 2. TS (Table 2) had a significant effect on egg weights (P = 0.018), but no effect on L* scores (P = 0.191). TS 1 and TS 3 eggs were significantly heavier than TS2 eggs.
Table 2.
Main effects on external eggshell quality parameters*.
| Storage | Weights (g) | L* Scores |
|---|---|---|
| Day 0 | 63.76a | 70.19c |
| Day 7 | 63.37ab | 71.09b |
| Day 14 | 63.00bc | 72.10a |
| Day 21 | 62.65c | 71.38b |
| Day 28 | 62.40c | 70.84b |
| SEM | 0.2241 | 0.2663 |
| P-Value | <0.0001 | <0.0001 |
| Storage | Average TS* | |
|---|---|---|
| Day 0 | 1.35e | |
| Day 1 | 1.54d | |
| Day 7 | 1.90c | |
| Day 14 | 1.96c | |
| Day 21 | 2.04b | |
| Day 28 | 2.13a | |
| SEM | 0.0354 | |
| P-Value | <0.0001 | |
| TS | Weights (g)⁎⁎ | L* Scores⁎⁎ |
|---|---|---|
| TS 1 | 63.22a | 70.91 |
| TS 2 | 62.71b | 71.10 |
| TS 3 | 63.38a | 71.51 |
| SEM | 0.2231 | 0.2526 |
| P-Value | 0.018 | 0.191 |
– differences within a column are denoted by differing superscripts.
– Proc Mixed Procedure with egg as the random variable and TS, storage, and the interaction of the two as the fixed variable.
– Translucency score is denoted by TS
⁎⁎⁎– Eggs were pooled from all storage points to determine these values.
Fig. 2.
Distribution of translucency score at each storage period.
Internal eggshell quality
A significant interaction effect was found on albumen height (P < 0.0001; Table 3) and Haugh units (P < 0.0001; Table 3). TS 3 eggs on day 1 had the highest albumen height, and TS 1 and TS 2 eggs on day 28 had the lowest albumen heights. Similarly, TS 3 eggs on day 1 had the highest Haugh unit, and TS 1 and TS 2 eggs on day 28 had the lowest Haugh units.
Table 3.
| Albumen Height | |||
|---|---|---|---|
| Storage | TS* 1 | TS 2 | TS 3 |
| Day 1 | 6.65bc | 6.71b | 7.44a |
| Day 14 | 6.77b | 6.55bc | 6.66b |
| Day 28 | 5.84d | 5.90d | 6.09cd |
| SEM | 0.2019 | ||
| P-Value | <0.0001 | ||
| Haugh Unit | |||
|---|---|---|---|
| Storage | TS 1 | TS 2 | TS 3 |
| Day 1 | 80.51ab | 80.32b | 84.30a |
| Day 14 | 80.58ab | 79.12bc | 79.81bc |
| Day 28 | 74.31d | 74.90d | 75.97cd |
| SEM | 1.4150 | ||
| P-Value | <0.0001 | ||
– differences are denoted by differing superscripts.
– Proc Mixed Procedure with egg as the random variable and TS, storage, and the interaction of the two as the fixed variable
⁎⁎– Translucency score is denoted by TS.
The storage period (Table 4) alone had a significant effect on albumen height and Haugh units (both P < 0.0001), but no effect on breaking strength (P = 0.819). Albumen height and Haugh units were highest on day 1 and day 14, and lowest on day 28. On day 1, there was a significant difference in albumen height with TS 3 having the highest albumen height, and TS 1 having the lowest (P = 0.041; Table 4). There were no other significant differences observed on day 1, day 14, or day 28 (Table 4).
Table 4.
Main effects on internal egg quality parameters and breaking strength for days 1, 14, and 28.
| Storage | Albumen Height (mm) | Haugh Unit | Breaking Strength (kg) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day 1 | 6.93a | 81.71a | 4.37 | ||||||||||||
| Day 14 | 6.66a | 79.84a | 4.41 | ||||||||||||
| Day 28 | 5.95b | 75.06b | 4.30 | ||||||||||||
| SEM | 0.1181 | 0.8176 | 0.1263 | ||||||||||||
| P-Value | <0.0001 | <0.0001 | 0.819 | ||||||||||||
| Day 1 | Day 14 | Day 28 | |||||||||||||
| TS*1 | TS 2 | TS 3 | SEM | P-Value | TS 1 | TS 2 | TS 3 | SEM | P-Value | TS 1 | TS 2 | TS 3 | SEM | P-Value | |
| ⁎⁎Albumen Height (mm) | 6.65 | 6.71 | 7.44 | 0.2382 | 0.041 | 6.77 | 6.55 | 6.66 | 0.2007 | 0.736 | 5.84 | 5.90 | 6.09 | 0.1589 | 0.502 |
| ⁎⁎Haugh Unit | 80.51 | 80.32 | 84.30 | 1.6549 | 0.168 | 80.58 | 79.12 | 79.81 | 1.3618 | 0.750 | 74.31 | 74.90 | 75.97 | 1.1888 | 0.610 |
| ⁎⁎Breaking Strength (kg) | 4.19 | 4.23 | 4.69 | 0.1990 | 0.148 | 4.33 | 4.67 | 4.23 | 0.2408 | 0.400 | 4.25 | 4.16 | 4.49 | 0.2125 | 0.528 |
– differences within a column are denoted by differing superscripts.
- Translucency score is denoted by TS.
– Eggs were pooled from all storage points to determine these values.
Yolk color was significantly affected by the storage period (P = 0.045; Table 5), but not by TS at any storage period (P = 0.641; P = 0.414; P = 0.663; Table 5). A similar pattern was found for egg grade; where egg grade was significantly affected by the storage period (P = 0.0456; Table 6), but not by TS at any storage period (P = 0.851; P = 0.574: P = 0.766; Table 6).
Table 5.
Main effects on yolk color for days 1, 14, and 28.
| Day 1 |
Day 14 |
Day 28 |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Yolk Color ⁎⁎ | TS*1 | TS 2 | TS 3 | TS 1 | TS 2 | TS 3 | TS 1 | TS 2 | TS 3 |
| 1 | 0.00 | 0.00 | 5.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
| 2 | 0.00 | 0.00 | 5.00 | 5.00 | 5.00 | 5.00 | 0.00 | 0.00 | 0.00 |
| 3 | 0.00 | 10.00 | 10.00 | 20.00 | 0.00 | 10.00 | 10.00 | 15.00 | 10.00 |
| 4 | 25.00 | 30.00 | 30.00 | 35.00 | 65.00 | 50.00 | 20.00 | 25.00 | 45.00 |
| 5 | 60.00 | 50.00 | 35.00 | 40.00 | 30.00 | 35.00 | 55.00 | 50.00 | 40.00 |
| 6 | 15.00 | 10.00 | 10.00 | 0.00 | 0.00 | 0.00 | 15.00 | 10.00 | 5.00 |
| 7 | 0.00 | 0.00 | 5.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
| P-Value | 0.641 |
0.414 |
0.663 |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Yolk Color | Day 1 | Day 14 | Day 28 | ||||||
| 1 | 1.67 | 0.00 | 0.00 | ||||||
| 2 | 1.67 | 5.00 | 0.00 | ||||||
| 3 | 6.67 | 10.00 | 11.67 | ||||||
| 4 | 28.33 | 50.00 | 30.00 | ||||||
| 5 | 48.33 | 35.00 | 48.33 | ||||||
| 6 | 11.67 | 0.00 | 10.00 | ||||||
| 7 | 1.67 | 0.00 | 0.00 | ||||||
| P-Value | 0.045 | ||||||||
– Translucency score is denoted by TS.
– Eggs were pooled from all storage points to determine these values.
Table 6.
Main effects on egg grade for days 1, 14, and 28.
| Day 0 |
Day 14 |
Day 28 |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| TS*1 | TS 2 | TS 3 | TS 1 | TS 2 | TS 3 | TS 1 | TS 2 | TS 3 | |
| ⁎⁎Grade AA (%) | 90.00 | 85.00 | 90.00 | 90.00 | 95.00 | 85.00 | 70.00 | 80.00 | 75.00 |
| ⁎⁎Grade A (%) | 10.00 | 15.00 | 10.00 | 10.00 | 5.00 | 15.00 | 30.00 | 20.00 | 25.00 |
| P-values | 0.851 |
0.574 |
0.766 |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Day 0 | Day 14 | Day 28 | |||||||
| Grade AA (%) | 88.33 | 90.00 | 75.00 | ||||||
| Grade A (%) | 11.67 | 10.00 | 25.00 | ||||||
| P-values | 0.046 | ||||||||
– Translucency score is denoted by TS.
– Eggs were pooled from all storage points to determine these values.
Discussion
External eggshell quality
No interaction effects between storage duration and TS were found for any of the external eggshell quality parameters. We hypothesize that no interaction was observed because egg TS is not a fixed parameter, and the egg was absorbing moisture throughout the entire storage period. Eggshell thickness was only significantly affected by eggshell TS; with TS 3 eggs having the highest thickness, which agrees with previous research conducted in laying hens (Talbot and Tyler, 1974; Wang et al., 2017) and broiler breeders (Orellana et al., 2023; Morris et al., 2025). The differences in eggshell thickness due to TS are most likely related to the differences in the ultrastructural arrangements of the eggshell in each of the different TS. Chousalkar et al. (2010) found that compared to non-translucent eggs, translucent eggs had good quality mamillary caps that were more closely adhered to the shell membrane. This increased attachment of the mamillary caps to the eggshell membranes could be the cause of the increased thickness that is observed in TS 3 eggs.
Storage duration had a significant effect on egg weights with day 0 being significantly higher than day 28. Our results align with previous research, that found egg weights on day 0 were significantly higher than on day 28, regardless of storage temperature (Scott and Silversides, 2000; Silversides and Scott, 2001; Jones and Musgrove, 2005; Wengerska et al., 2023). As the storage period progresses, the eggshell quality deteriorates allowing for more moisture to be evaporated out of the eggshell, resulting in a lower egg weight. Egg weights were also significantly affected by TS, with TS 1 and TS 3 eggs being heavier than TS 2 eggs. We hypothesize that these differences are due to TS 1 eggs having minimal areas of translucency that hinder the internal content’s ability to evaporate out of the eggshell; conversely, TS 3 eggs have an increased incident of translucent areas, indicating that the moisture from the internal contents has not been able to completely evaporate out, and is getting caught in the ultrastructural arrangement of the eggs, and thus increasing the weight of the egg. Previous research from laying hens of similar ages found conflicting results. Wang et al. (2017) found that there was no difference in egg weight between opaque and translucent eggshells in 50-week-old White Leghorn pure line hens, whereas Ren et al. (2023) found that egg weight was significantly higher in translucent eggs compared to opaque eggs in 67-week-old Rhode Island Red-White Layers. Further research should be conducted to fully understand the effect TS has on egg weights.
L* scores were only significantly influenced by the storage duration. L* scores increased from day 0 to 14 and then decreased from day 14 to day 28. A previous study found that eggs that were washed had a higher L* score value regardless of storage duration (Kim et al., 2024). Therefore, we hypothesize that the washing of eggs in this study could have caused the increase in L* score from day 0 to day 14. However, to our knowledge, there have been no other studies conducted evaluating the effect of storage on L* score, and the findings from this study warrant the need for further research in this area.
Translucency score was significantly impacted by the storage period. The significant increase in TS from day 0 to day 1 highlights the need for a 24-hour drying period to ensure all translucent spots are developed before TS measurements are taken (Talbot and Tyler, 1974). Measuring TS on day 0 could lead to misclassifications due to the translucent spots not being fully developed and thus result in inaccurate eggshell quality determinations. On day 0, the average TS was 1.35 and increased to an average of 2.13 by the end of the storage period. We hypothesize that TS was significantly affected by the storage duration because a longer storage duration resulted in more moisture that could be evaporated out of the internal contents and into the ultrastructure of the eggshell resulting in an increase in the TS of the eggs. Further research should be conducted to evaluate how other storage temperatures and durations affect TS.
Breaking strength was not significantly impacted by the storage period or TS in this study. Previous research has found that regardless of storage duration, there is not a difference in breaking strength (Jones and Musgrove, 2005), which aligns with the results we observed. However, it has previously been found that TS does affect eggshell breaking strength (Garlich et al., 1975). The differences between our study and the previous study could be that in our study we used a three-point scale for TS whereas they classified eggs as opaque or translucent. We hypothesize that the strength of the eggshell is more closely related to amount of calcium found in the eggshell, which is not changed by either the storage duration or TS. Further research should be conducted to determine how the three-point TS scale affects breaking strength.
Internal eggshell quality
A significant storage and TS interaction was found on albumen heights and Haugh units. Previous research has shown that as the storage period increased, albumen height (Scott and Silversides, 2000; Silversides and Scott, 2001; Jones and Musgrove, 2005) and Haugh units (Jones and Musgrove, 2005; Wengerska et al., 2023) are significantly decreased. In these studies, egg storage temperature varied, 20°C, 20°C, 4°C, and 14°C, respectively, compared to our storage temperature of 4°C, however, we did still find similar results. Previous research conducted by Wang et al. (2017) found that TS did not affect albumen height or Haugh units. To our knowledge, previous research has not been conducted looking at the interaction of TS and storage duration and its effect on albumen height and Haugh units. Based on the results we observed in this study, we hypothesize that eggs with a TS 3 degrade faster than all other eggs, as there was a significant decrease in both the albumen height and Haugh units from day 1 to 14 and from day 14 to 28. Whereas in TS 1 and TS 2 eggs, the albumen height and Haugh units on day 1 were similar to the results on day 14, and a significant decrease was observed from day 14 to day 28. However, it should be noted that regardless of degradation rate, eggs with a TS 3 had higher numerical values for both albumen height and Haugh units at each time point.
Haugh units are directly linked to the grade of the eggs, where a Haugh unit over 72 represents Grade AA, 60-72 represents Grade A, and less than 60 represents Grade B (USDA AMS 56, 2000). There was no effect of TS on egg grade at any of the storage periods. However, there was a significant difference in the prevalence of egg grades due to the storage duration. The eggs utilized on day 14 yielded the highest amount of grade AA eggs (90 %), whereas the eggs utilized on day 28 yielded the lowest amount of grade AA eggs (75 %); it is important to note that the grade determination was made based on the Haugh units of eggs used at each internal quality measurement. Jones and Musgrove (2005) found that eggs could be stored for up to 10 weeks without egg grades, based on average Haugh units, falling below grade A. Our results show the prevalence of grade AA and grade A eggs whereas Jones and Musgrove (2005) based their grade measurements on the average Haugh units of all the eggs, to determine the overall egg grade of the entire collection of the eggs, which could potentially be masking the prevalence of a lower Haugh unit and thus a lower grade egg.
Previous research has found that TS affects yolk color, with a highly translucent egg having a darker-colored yolk compared to more opaque eggs (Wang et al., 2017); however, in our study, TS did not affect yolk color. The differences observed between the previous study and our study could be due to the differences in the breed of hen used. Wang et al.’s (2017) study utilized brown egg dwarf layers whereas we used Hyline W-36 s. Storage duration significantly affected egg yolk color. On days 1 and 28, there was a higher prevalence of a darker-colored egg yolk compared to day 14. Previous research has suggested that yolk color is significantly reduced as the storage period increases (Jin et al., 2011). This reduction could be caused by the membrane degradation that allows water and other albumen properties to enter the yolk and dilute the color. In our study, we discovered a different pattern, however, our study looked at storage for up to 28 days, whereas the study mentioned above only looked at storage for up to 10 days.
Conclusion
Eggshell quality does significantly degrade throughout the storage period at a refrigerated temperature of 4°C. Based on our results, TS could be used to predict some internal egg quality parameters. However, the results found in this study are inconclusive on whether TS could serve as an effective predictive parameter of overall eggshell quality throughout the storage period. Further research should be conducted to further evaluate the use of translucency score as a predictive parameter of overall egg quality throughout the storage period.
CRediT authorship contribution statement
Cassidy A Morris: Data curation, Formal analysis, Investigation, Writing – original draft. Leticia Orellana: Investigation, Methodology, Writing – review & editing. Charis Waters: Methodology. Pratima Adhikari: Resources, Writing – review & editing. Kenneth Macklin: Funding acquisition, Supervision, Writing – review & editing.
Disclosures
All authors have participated in (a) conception and design, or analysis and interpretation of the data; (b) drafting the article or revising it critically for important intellectual content; and (c) approval of the final version.
This manuscript has not been submitted to, nor is under review at, another journal or other publishing venue.
The authors have no affiliation with any organization with a direct or indirect financial interest in the subject matter discussed in the manuscript
Acknowledgements
We would like to thank the Mississippi Agriculture and Forestry Experiment Station for their financial support during this study.
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