Storage Time Research Articles

Impact of storage time on microbial communities and flavor profiles in highland barley grains

Microbial activity and the resulting flavor changes in stored highland barley grains may reduce the product quality and pose potential risks to food safety with economic losses. This study aims to elucidate the association between microbial load and flavor compounds during the preservation of highland barley. High-throughput sequencing (HTS) was used to investigate the microbial composition in stored highland barley. The volatile flavor components of the latter were identified via the headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Moreover, the study examined the correlation between the types of microorganisms and volatile flavor molecules. The results indicated that the dominant phyla in highland barley were Ascomycota and Basidiomycota, with the dominant genera being Cladosporium, Vishniacozyma, Filobasidium, Udeniomyces, Cystofilobasidium, Aspergillus, Alternaria, Monographella, Didymella, and Neoascochyta. Inside，Cystofilobasidium, Itersonilia, Sarocladium, Ustilago, Penicillium and Pyrenophora served as effective biomarkers to distinguish highland barley grains stored at different times. Further, the highland barley samples contained 192 volatile organic compounds (VOCs), such as alcohols, ketones, esters, alkanes, aldehydes, etc. The top 20 volatile flavor compounds with differences were selected based on the variable importance of projection (VIP) > 1. Based on the correlation analysis findings, it was found that the genera Cystofilobasidium, Aspergillus, and Cladosporium hold promise in contributing volatile flavor compounds to highland barley. This study examined a pattern of changes in safety and quality across varying storage durations, providing crucial insights to enhance the flavor profile and texture of highland barley products.

Identification of Codonopsis Radix from different sources by integrating high‐performance liquid chromatography fingerprinting with chemometric approaches and Lobetyolin determination

AbstractCodonopsis Radix (CR) is often used as both a medicine and a food ingredient. However, identifying CR can be difficult due to various factors such as variety, sulfur fumigation, and storage time. Consequently, a comprehensive strategy based on fingerprinting and chemometric approaches was developed to distinguish different CRs. First, the fingerprints of CR were acquired by high‐performance liquid chromatography (HPLC). Secondly, various chemical pattern recognition methods were employed to identify CR. Additionally, 14 and 16 major compounds were identified as marker compounds to differentiate between different varieties and sulfur‐fumigated samples, respectively. Furthermore, the amount of Lobetyolin present in different samples was determined, showing that the content of Lobetyolin varied significantly across the samples. Codonopsis pilosula Nannf. var. modesta (Nannf.) L.T.Shen had the highest content of Lobetyolin, followed by Codonopsis tangshen Oliv., and Codonopsis pilosula (Franch.) Nannf. In addition, the content of Lobetyolin was highest when it was non‐sulfur‐fumigated and stored for 0 years. Conclusively, HPLC fingerprint in conjunction with chemical pattern recognition and component content determination, can be employed to differentiate different varieties and sulfur‐fumigated CR. Additionally, it is a reliable, comprehensive, simple, and rapid method for the identification of CR.

Microbiological and Physicochemical Evaluation of Hydroxypropyl Methylcellulose (HPMC) and Propolis Film Coatings for Cheese Preservation.

Dairy products are highly susceptible to contamination from microorganisms. This study aimed to evaluate the efficacy of hydroxypropyl methylcellulose (HPMC) and propolis film as protective coatings for cheese. For this, microbiological analyses were carried out over the cheese' ripening period, focusing on total mesophilic bacteria, yeasts and moulds, lactic acid bacteria, total coliforms, Escherichia coli, and Enterobacteriaceae. Physicochemical parameters (pH, water activity, colour, phenolic compounds content) were also evaluated. The statistical analysis (conducted using ANOVA and PERMANOVA) showed a significant interaction term between the HPMC film and propolis (factor 1) and storage days (factor 2) with regard to the dependent variables: microbiological and physicochemical parameters. A high level of microbial contamination was identified at the baseline. However, the propolis films were able to reduce the microbial count. Physicochemical parameters also varied with storage time, with no significant differences found for propolis-containing films. Overall, the addition of propolis to the film influenced the cheeses' colour and the quantification of phenolic compounds. Regarding phenolic compounds, their loss was verified during storage, and was more pronounced in films with a higher percentage of propolis. The study also showed that, of the three groups of phenolic compounds (hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids), hydroxycinnamic acids showed the most significant losses. Overall, this study reveals the potential of using HPMC/propolis films as a coating for cheese in terms of microbiological control and the preservation of physicochemical properties.

Hydrogen bonding dominated self-assembly mechanism of amphiphilic molecules in Chinese Baijiu

Molecular mechanisms underlying the aging of Chinese Baijiu remained elusive. This study proposed the self-assembly behavior of amphiphilic molecules dominated by hydrogen bonds in Chinese Baijiu for the first time. The self-assembly degree of amphiphilic clusters gradually intensifies with the prolonged storage time of Baijiu, comprehensively characterized at both micro and macro levels. The results indicated that the blue-shift of the Raman hydrogen bond vibrational peak (about 11 cm−1 and 7 cm−1, respectively), the increase in viscosity (5.71% and 2.22%, respectively), and the rise in dielectric constant (95.63% and 94.99%, respectively) during the 17-year cellaring process of Strong-flavor Baijiu and Jiang-flavor Baijiu were consistent with the evolutionary trends observed in molecular dynamics simulations. The essential driving factors of cluster structure alteration of amphiphilic aroma substances in Chinese Baijiu during cellaring were demonstrated from molecular level. This study provided a research approach to comprehending the aging mechanism of Chinese Baijiu from the micro level.

Evaluation of Dynamic Changes of Volatile Organic Components for Fishmeal during Storage by HS-SPME-GC-MS with PLS-DA.

Headspace solid-phase microextraction, combined with gas chromatography-mass spectrometry and partial least squares discriminant analysis, was adopted to study the rule of change in volatile organic compounds (VOCs) for domestic and imported fishmeal during storage with different freshness grades. The results showed that 318 kinds of VOCs were detected in domestic fishmeal, while 194 VOCs were detected in imported fishmeal. The total relative content of VOCs increased with storage time, among which acids and nitrogen-containing compounds increased significantly, esters and ketones increased slightly, and phenolic and ether compounds were detected only in domestic fishmeal. Regarding the volatile base nitrogen, acid value, pH value, and mold counts as freshness indexes, the freshness indexes were significantly correlated with nine kinds of VOCs (p < 0.05) through the correlation analysis. Among them, volatile base nitrogen had a significant correlation with VOCs containing nitrogen, acid value with VOCs containing carboxyl group and hydrocarbons, pH value with acids which could be used to adjust pH value, and mold counts with part of acids adjusting pH value and VOCs containing nitrogen. Due to the fact that the value of all freshness indexes increased with freshness degradation during storage, based on volatile base nitrogen and acid value, the fishmeal was divided into three freshness grades, superior freshness, corrupting, and completely corrupted. By using partial least squares discriminant analysis, this study revealed the differences in flavor of the domestic and imported fishmeal during storage with different freshness grades, and it identified four common characteristic VOCs, namely ethoxyquinoline, 6,7,8,9-tetrahydro-3H-benzo[e]indole-1,2-dione, hexadecanoic acid, and heptadecane, produced by the fishmeal samples during storage, as well as the characteristic VOCs of fishmeal at each freshness grade.

Numerical simulation of a thermal energy storage system using sunrise and sunset transient temperature models

The temperature of the sun was modeled in this study using two transient solar temperature equations for sunrise and sunset that were developed for designing a latent heat thermal energy storage (LHTES) system for a concentrated solar power (CSP) plant. The derivation of the equations was based on the existing solar hour angle and the fundamental periodic function equations. Ansys' computational fluid dynamics code was used to investigate numerically the transient response of the conjugate melting and solidification of a phase change material (PCM) in a cylindrical shell and helical heat pipe (HHP) thermal system. The models for both equations were applied as user-defined functions (UDFs). The heat transfer medium was air. The predicted liquid and solid fractions provide quantitative data on the temperature and the stored solar energy. The effectiveness of both models in enhancing heat transfer and their suitability as real-time transient solar temperature models in heat transfer engineering is demonstrated by comparisons between their outputs. With high agreement, experimental data from the open literature was used to validate the numerical model's predictions. The solar temperature models aim to contribute to heat transfer enhancement for a reduced PCM energy storage time in designing a high-temperature solar thermal storage that is adequate to maintain a steady supply of electricity and energy for domestic and commercial applications and to accelerate the global transition to low-carbon energy.

Prediction of the Freshness of Grass Carp during Storage with Electric Nose Based on Signal Sequence Merging and Wavelet Transform

In order to predict the freshness of grass carp, a novel data preprocessing method was proposed for electronic nose (E-nose) signals. The signal sequences from six sensors were selected and subsequently normalized. The direct signal sequence merging (DSSM) and reversed signal sequence merging (RSSM) modes were used for signal sequence merging. Subsequently, the genetic algorithm (GA) was used to evaluate the contribution of diverse sensors, and the merged data sequence was compressed using wavelet transform (WT). Using approximation coefficient and detail coefficient based on different scales and different signal sequence merging modes, principal component analysis (PCA) discriminated successfully storage time of chilled fish fillet. The PCA plots clearly demonstrated that all extracted feature data fully retain the signal characters. The partial least squares (PLS) and artificial neural network (ANN) models were used to establish prediction models for the freshness of grass carp during storage. The DSSM-ANN-A5 and DSSM-PLS-D4 models were chosen as the TVB-N content prediction models, while the DSSM-ANN-D5 and RSSM-PLS-A0 models were selected as the K value prediction models. The R2 values of these models are higher than 0.9, and they have a good coefficient of determination. The results of this study suggest that it using E-nose signals to predict TVB-N content and K value is an effective method for assessing the freshness of grass carp during storage.

Polymer-coated urea applied at one-time mechanical topdressing increases nitrogen use efficiency and rice yield in the cold area

Context The application of slow and controlled release fertilisers can reduce nitrogen loss, but the research is still scarce in the cold rice region of China. Aims The study was conducted to screen slow-release or controlled-release fertilisers which can meet the nitrogen demand of rice and reduce NH3 volatilisation in different pH soils. Methods This experiment includes four fertilisation treatments: no fertiliser (control), urea, urea with N-(n-butyl) thiophosphorictriamide (NBPT), and polymer-coated urea (PCU). The amounts of urea-N, pH, ammonium-N (NH4+-N) in the surface water, and NH3 volatilisation were determined. Thereafter, to evaluate the effects of one-time mechanical topdressing of PCU mixed with compound fertilisers along with farmers’ fertilisation practice (FFP), field experiments carried out in wide soil pH differences were conducted. Key results Cumulative NH3 volatilisation was reduced in the NBPT treatment compared with the urea treatment. There was no significant difference between urea-N, NH4+-N, and pH in the surface water under PCU and control. NH3 volatilisation of PCU is negligible and significantly prolongs the soil nitrogen storage time. In the subsequent experiment, PCU blend increased yield, dry matter, nitrogen uptake, and the partial factor productivity of applied nitrogen (PFPN) compared to FFP. Conclusions PCU treatment slows down urea release and reduces ammonia volatilisation from paddy fields. In turn, it reduces ammonia-nitrogen levels and pH in surface water and further slows down the rate of ammonia volatilisation. Implications Application of PCU as a one-time mechanical topdressing fertiliser in rice fields in cold regions saves nitrogen fertiliser, increases crop yields, and reduces labour.

Amplicon sequencing and shotgun metagenomics reveal functional impacts of aminoethoxyvinylglycine-mediated ripening and cold storage on the microbiome of ‘NY1’ apples

Understanding community-level microbial dynamics provides more holistic insight into the nature of pathogen infection and biocontrol in fruits and vegetables. We investigated the impact of preharvest sprays of aminoethoxyvinylglycine (AVG, 0.25 g L−1), an inhibitor of ethylene production of fruit, to assess the association between ethylene-mediated ripening and the microbiome at harvest and during storage. ‘NY1’ (Snapdragon®) apples were sprayed on the tree two weeks before first harvest and the microbiome of the fruit was assessed at harvest and at one-week intervals across four weeks. Fruit from harvests 1 and 4 were stored in air at 3 °C for up to 6 months. The bacterial communities changed over harvest time while fungal communities were affected by AVG treatment. In addition, both harvest time and AVG, as well as storage time, were associated with bacterial and fungal variation after 2–6 months of storage. Postharvest fungal microbiomes showed consistent responses to variations in fruit maturation, with the microbial communities of AVG-treated apples being similar to those of early harvested apples. Fungal microbiome variation was linked to the soluble solids concentration and IAD, revealing further links between microbial dynamics and apple quality. Bacterial shifts that occurred from harvest to 6 months of storage were characterized by metagenome changes that resulted in a lower abundance of biofilm formation pathways after cold storage, which may limit the ability of these bacterial communities to block colonization by fungal pathogens. These findings advance our understanding of how the microbiome is connected to fruit quality and functional metagenomics related to biocontrol.

Novel PVA-based foams for cold chain logistics with high efficiency

The rapid advancement of fresh e-commerce has driven the growth of the cold chain logistics, which spurs a significant demand for the upgrading of the phase change material (PCM) ensuring the transported items maintain at the required low temperature. This paper reported a novel form-stable phase change material poly (vinyl alcohol) (PVA) -based foams (FPCMPFs) with high efficiency fabricated by combining thermal foaming of PVA and in-situ polymerization of polyacrylic acid (PAA). The constructed double network structure improved the water storage to as high as 85.81 wt%, and enhanced the mechanical strength to maintain the shape stability even under 60 % compressive strain, which endowed FPCMPFs with good cold storage performance with high latent heat of 309.6 J/g, and prevented the water leakage in use. 65 g FPCMPFs located in a 7.0 × 7.0 × 10.5 cm box extended the storage time of the precooled grapes at -1-0 °C keeping at 5 °C from 28.7 min to 229.1 min, demonstrating the significant prospects for application in the cold chain logistics.

Effect of formalin-fixation and paraffin-embedded tissue storage times on RNAscope in situ hybridization signal amplification.

RNAscope in situ hybridization (ISH) detects target RNA in formalin-fixed, paraffin-embedded (FFPE) tissues. Protocols suggest that prolonged FFPE storage and formalin fixation may impact signal detection, potentially limiting the utility of RNAscope ISH in retrospective studies. To develop parameters for RNAscope use with archived specimens, we evaluated the effect of formalin-fixation time by measuring the signal of a reference gene (16srRNA) in selected tissues fixed in 10% neutral-buffered formalin for 1, 2, 3, 5, 7, 10, 14, 21, 28, 60, 90, 180, and 270 d. The signal intensity and percent area of signal decreased after 180 d. Tissues had detectable signal at 180 d but not at 270 d of formalin fixation. To assess target detection in paraffin blocks, we qualitatively compared the signal of canine distemper virus (CDV) antigen via immunohistochemistry and CDV RNA via RNAscope ISH in replicate sections from blocks stored at room temperature for 6 mo, 1, 3, 6, 8, 11, 13, and 15 y; RNA was detected in FFPE tissues stored for up to 15 y. Our results demonstrate that RNAscope ISH can detect targets in tissues with prolonged paraffin storage intervals and formalin-fixation times.

Effects of Long-Term Cryopreservation on the Transcriptomes of Giant Grouper Sperm.

The giant grouper fish (Epinephelus lanceolatus), one of the largest and rarest groupers, is a fast-growing economic fish. Grouper sperm is often used for cross-breeding with other fish and therefore sperm cryopreservation is important. However, freezing damage cannot be avoided. Herein, we performed a transcriptome analysis to compare fresh and frozen sperm of the giant grouper with frozen storage times of 0, 23, 49, and 61 months. In total, 1911 differentially expressed genes (DEGs), including 91 in El-0-vs-El-23 (40 upregulated and 51 downregulated), 251 in El-0-vs-El-49 (152 upregulated and 69 downregulated), and 1569 in El-0-vs-El-61 (984 upregulated and 585 downregulated), were obtained in the giant grouper sperm. DEGs were significantly increased at 61 months of cryopreservation (p < 0.05). GO and KEGG enrichment analyses of the DEGs revealed significant enrichment in the pilus assembly, metabolic process, MAPK signaling pathway, apoptosis, and P53 signaling pathway. Time-series expression profiling of the DEGs showed that consistently upregulated modules were also significantly enriched in signaling pathways associated with apoptosis. Four genes, scarb1, odf3, exoc8, and atp5f1d, were associated with mitochondria and flagella in a weighted correlation network analysis. These genes may play an important role in the response to sperm freezing. The experimental results show that long-term cryopreservation results in freezing damage to the giant grouper sperm. This study provides rich data for studies of the mechanism underlying frozen fish sperm damage as well as a technical reference and evaluation index for the long-term cryopreservation of fish sperm.

Global patterns in river water storage dependent on residence time

Accurate assessment of global river flows and stores is critical for informing water management practices, but current estimates of global river flows exhibit substantial spread and estimates of river stores remain sparse. Estimates of river flows and stores are hampered by uncertainties in land runoff, an unobserved quantity that provides water input to rivers. Here we leverage global river flow observations and an ensemble of land surface models to generate a globally gauge-corrected monthly river flow and storage dataset. We estimate a global river storage mean (± monthly variability) of 2,246 ± 505 km3 and a global continental flow of 37,411 ± 7,816 km3 yr−1. Our global river water storage time series demonstrates that flow wave residence time is a fundamental driver that can double or halve river water stores and their variability. We also reconcile the wide range in previous estimates of monthly variability in global river flows. We identify previously underappreciated freshwater sources to the ocean from the Maritime Continent (Indonesia, Malaysia and Papua New Guinea) amounting to 1.6 times the Congo River and illustrate our capability of detecting severe anthropogenic water withdrawals.

Visualisation of moisture content distribution maps and classification of freshness level of loquats

Moisture content (MC) and freshness undergo evident changes during the storage of loquat fruits and thus are important indices of loquat fruit quality. Conventional methods for assessing MC and freshness are typically destructive and time-consuming, and cannot provide distribution maps of MC in the whole loquats. In this study, the use of hyperspectral imaging (HSI) was investigated for rapid and non-destructive prediction of MC in loquats, and for the visualisation of their MC distribution maps. Furthermore, freshness level discrimination models for loquats at different storage times were established using partial least squares discriminant analysis (PLS-DA), multinomial logistic regression (MLogR), and back-propagation neural network (BPNN) classification models. MC was well-predicted, with the best residual predictive deviation (RPD) of 2.40. Using the best prediction model, the distribution maps of MC in loquats were visualised. Additionally, the competitive adaptive reweighted sampling (CARS)-BPNN model obtained superior discrimination performance, with 95.56 % and 93.33 % accuracy for the calibration and prediction sets. Our results show that HSI is a promising fast and non-destructive method for determining MC and freshness of loquats.

White light diffraction phase microscopy for imaging of red blood cells for different storage times

In this study, the effects of different storage times on the surface morphology of red blood cells (RBCs) were investigated using white light diffraction phase microscopy (WDPM). Blood samples collected from 10 volunteer and stored for 56 days, were imaged on WDPM at every 7 days without any sample preparation. To obtain the phase profiles of RCBs, first the sample and then the reference interferograms were obtained from the experimental setup. Then, surface profiles were calculated from these interferogram images using Fourier transform (FT). With the experiment performed every 7 days, 10 RBC phase information were obtained from each sample and surface profiles were created. From these profiles, 7 parameters related with RBC morphology (average cell thickness—ACT; mean corpuscular volume—MCV; projected surface area—PSA; total surface area—SA; diameter—D; mean corpuscular haemoglobin—MCH; surface area to volume ratio - SAV) have been calculated. Therefore, changes in the morphology of RBCs during storage were evaluated quantitatively. Additionally, phase calibration target was used to confirm the accuracy of our experimental setup system. From the interferogram images, the depth of the phase target (GRP 9 and element 3) was obtained as 309 nm, in accordance with the produced depth. By this way, the reliability of the WDPM setup is demonstrated. This study suggests that the morphology of RBCs can be quantitatively obtained in a reliable manner at higher resolution with WDPM without sample preparation.

Study on Clarification Effect and Stability of Fragrans Mead by Clarification Process

In order to study the best clarification conditions of osmanthus honey wine, single factor experiment and orthogonal experiment were used. The experimental results show that: When the type of clarifying agent was chitosan, the concentration of clarifying agent was 0.25%, and the clarifying time was 14 h, the maximum light transmittivity was 80.8±0.10%. After cold and hot treatment, standing at room temperature and oxidation stability test results showed that the stability of osmanthus honey wine with chitosan and potassium pyrosulfite was the best, and the wine body could not only maintain the flavor of the original wine, but also maintain the flavor of the original wine. The storage time is longer.After clarification, the sensory evaluation of the product was 86.9±0.69 points, the light transmittance was 80.8±0.10%, and the alcohol content was 6.4±0.05 %Vol.

Effect of selenium nanoparticles-supplemented INRA96 extender on Turkmen stallion sperm quality and lipid peroxidation during storage at 5°C.

Oxidative damage to sperm during cooled storage is a significant issue, and selenium with antioxidant potential could be a solution. Moreover, nano-sized selenium offers more advantages compared to its ionic forms. This research aimed to assess the impact of selenium nanoparticles (SeNPs) supplemented in the INRA96 extender on the quality of Turkmen stallion sperm and lipid peroxidation during 72 h of cooled storage. A total of 25 ejaculates were treated using different concentrations of SeNPs, including no SeNPs (Control), 0.5 μM SeNPs (SeNPs 0.5), 1.0 μM SeNPs (SeNPs 1.0), and 1.5 μM SeNPs (SeNPs 1.5). The samples were then evaluated for sperm quality characteristics and lipid peroxidation. The results indicated a significant decrease (P < 0.05) in total and progressive motility, viability, and plasma membrane functionality after 48 h of cooled storage, along with an increase (P < 0.05) in spermatozoa abnormality and malondialdehyde (MDA) levels as the cooled storage time increased. However, SeNPs demonstrated an improvement (P < 0.05) in sperm total motility after 24 h of cooled storage, progressive motility throughout the entire 72-hour period, functionality of the plasma membrane after 48 hours of cooled storage, spermatozoa abnormality after 48 h of cooled storage, and semen MDA levels throughout the cooled storage (P < 0.05). In conclusion, the enrichment of the INRA96 extender with nano-sized selenium can enhance the quality of Turkmen stallion sperm during storage at 5°C by increasing total, progressive, and curvilinear motilities, improving plasma membrane functionality, and reducing sperm abnormalities and lipid peroxidation.

Effect of fermentation agents on the pH, tta and microbial composition of &lt;i&gt;Fufu&lt;/i&gt; dough

Fufu, a product of cassava has been adulterated by processors. They add toxic substances to the soaked roots to fasten the fermentation days and make quick money. There is need to evaluate the effect of these fermentation agents on the microbial, pH and total titratable acidity (TTA) of the fufu dough. Fufu dough was produced with fermentation agents; kerosene, detergent and palm ash and also with a control without agent. They were wrapped in polyethylene bags, stored at ambient temperature and evaluated for storage and microbial quality in the Biochemistry Laboratory of National Root Crops Research Institute, Umudike, Nigeria. These samples were assayed for chemical and microbial qualities which include pH and TTA. The results showed that the pH values ranged from 3.70 - 6.80, and Total Titratable Acidity (TTA) values ranged from 0.004 - 0.048 %. The microbial analysis showed increase in fungal (2.1×108 (cfu/g)) and bacterial (1.0 ×106 (cfu/g)) counts as the storage time increased with the control having the least microbial load. The fungal isolates from the samples are Aspergillus niger, Aspergillus flavus and Penicillium spp, while the bacteria isolates from the samples include Bacillus spp and Staphylococcus aureus. Statistically, there were significant differences (p&lt;0.05) in appearance of the fufu as storage time increased. The results from this study showed that the fufu with fermenting agents had higher microbial load than the control. It therefore encourages healthy practices among the fufu producers by stopping the use of fermenting agents to reduce the proliferation of pathogenic microorganisms in processed fufu.

The Impact of Blood Sample Processing on Ribonucleic Acid (RNA) Sequencing.

In gene quantification and expression analysis, issues with sample selection and processing can be serious, as they can easily introduce irrelevant variables and lead to ambiguous results. This study aims to investigate the extent and mechanism of the impact of sample selection and processing on ribonucleic acid (RNA) sequencing. RNA from PBMCs and blood samples was investigated in this study. The integrity of this RNA was measured under different storage times. All the samples underwent high-throughput sequencing for comprehensive evaluation. The differentially expressed genes and their potential functions were analyzed after the samples were placed at room temperature for 0h, 4h and 8h, and different feature changes in these samples were also revealed. The sequencing results showed that the differences in gene expression were higher with an increased storage time, while the total number of genes detected did not change significantly. There were five genes showing gradient patterns over different storage times, all of which were protein-coding genes that had not been mentioned in previous studies. The effect of different storage times on seemingly the same samples was analyzed in this present study. This research, therefore, provides a theoretical basis for the long-term consideration of whether sample processing should be adequately addressed.

Internal quality of commercial eggs subjected to different shell treatments and storage times

Five hundred sixty eggs from commercial layers aged 74 weeks were subjected to sanitization and shell-covering procedures. The treatments consisted of two egg sanitization methods, sanitized (S) and not sanitized (NS), and two methods of shell covering, not covered (NC) and covered (C) with whey protein concentrate solution, arranged in a completely randomized design in a 2 × 2 factorial scheme (sanitization × shell coating), with five replications obtained from the average of four eggs evaluated in seven storage periods (1, 7, 14, 21, 28, 35, and 42 days). Albumen pH and yolk lipid oxidation using the TBARS test were evaluated. The averages for each period were submitted to analysis of variance, any differences observed were submitted to the Tukey test (5%), and regression analysis was performed between periods for each method. Using SDS-PAGE, the protein profile of albumen at 1 and 42 days was evaluated descriptively. Using methods S and NS, the pH and TBARS of eggs did not change on any of the days evaluated (P&gt;0.05). Methods C and NC had similar pH values (P&gt;0.05) only when using fresh eggs; however, the pH was higher when using eggs from Method NC (P&lt;0.0001) compared with Method C. For all techniques, the analysis of pH regression between periods revealed quadratic behavior. While regression analysis demonstrated an increasing linear behavior for all methods, the TBARS analysis results for C and NC on all evaluated days were comparable (P&gt;0.05). Whey protein concentrate does not affect the pH of sanitized eggs. The protein profile of the albumen and TBARS values of egg yolks stored at room temperature are unaffected by sanitation and whey protein concentrate covering, and TBARS values increase over storage days in all cases.