Nondestructive characterization gender of chicken eggs by odor using SPME/GC-MS coupled with chemometrics.

It's a difficult task for researchers to identify the gender of chicken eggs by nondestructive approach in the early of incubation, which not only could reduce the cost of incubation, but also could improve the welfare of chicks. Therefore, SPME/GC-MS has been applied to investigate its potential as a nondestructive tool for characterizing the differences of odor between male and female chicken eggs during early of incubation and even before hatch. The results showed that more volatiles were found in female White leghorn eggs during early of incubation and 6,10-dimethyl-5,9-undecadien-2-one, 6-methyl-5-hepten-2-one, nonanal, decanal, octanal, 2-nonen-1-ol, etc.

Characterization and classification of volatiles from different breeds of eggs by SPME-GC-MS and chemometrics.

Volatiles of shell eggs were identified by SPME-GC-MS to characterize and discriminate white Leghorn (W), Hy-line brown (H) and Jing fen (J) hatching eggs with comparison, principal components (PC), partial least squares (PLS), random forest classification (RFC) and canonical discriminant (CD) analyses. DVB/CAR/PDMS fiber and extraction 60 min were suited to analyze the volatiles emitted from eggs. A total of 17 or 18 volatile compounds were identified in raw shell hatching eggs, namely, nonanal, decanal and 6-methly-5-hepten-2-one were the main volatile components with contributions that over 70%.

Non-destructive characterization of egg odor and fertilization status by SPME/GC-MS coupled with electronic nose.

Background: Early and non-destructive identification of fertile (F) eggs is a difficult task in the process of breeding laying hens. The odors emitted from unfertilized (UF), infertile (IF), and fertile (F) eggs were characterized by solid-phase microextraction / gas chromatograph-mass spectrometry (SPME/GC-MS) and electronic nose (E-nose) to determine their differences by principal component, partial least squares, and canonical discriminant analyses.

Results: A total of 14 volatiles were identified in unhatched shell white Leghorn eggs, such as nonanal, decanal, 6-methyl-5-hepten-2-one, and 6,10-dimethyl-5,9-undecadien-2-one.

Study on Non-Destructive Detection Method for Egg Freshness Based on LLE-SVR and Visible/Near-Infrared Spectrum.

The freshness of egg is an important index to reflect the internal quality. In order to achieve non-destructive detection of freshness, micro fiber spectrometer was used to sample 550～950 nm transmittance spectra of eggs which performed quantitative analysis with haugh unit of eggs. Different pretreatment was combined with partial least squares regression(PLS) and support vector regression(SVR) respectively to find that first derivative combined with SVR predicted better than others through comparison, and it was better to model by SVR than by PLS.

[Quantitative Approach to Melamine Detection in Egg White with Surface-Enhanced Raman Spectroscopy].

Due to the harmfulness of melamine to human, the quantitative detection of melamine in egg is very necessary. In the present study, the surface enhanced Raman spectra technology combined with chemometric analysis method was used to conduct melamine quantitative detection in egg white. Firstly, the melamine egg sample could be got by the method of artificial feeding hens usingdifferent feeding formulation.

[Study on the stability of chicken egg yolk immunoglobulin (IgY) modified with mPEG].

The objective of the present paper was to study the effect of monomethoxypolyethlene glycol (mPEG) modification on the stability of chicken IgY and compare the stability of the modification products by Fourier transform infrared spectroscopy (FTIR), CD spectrooscopy and fluorescence spectroscopy. NHS-mPEG was used to modify IgY after mPEG was activated with N-hydroxysuccinimide (NHS). The optimal reaction condition for modification was 1:10 molar rate of IgY to mPEG at pH 7, reaction for 1 h, and the product was obtained with modification rate of 20.

[Effect of heat treatment on the allergenicity and microstructure of ovomucoid].

The effect of heat treatment on the allergenicity and microstructure of ovomucoid was studied by enzyme-linked immunosorbent assay (ELISA), CD spectra, ANS fluorescence probe emission spectra and UV absorption spectra. The results showed that the allergenicity of ovomucoid decreased with increasing temperatures and time. CD spectra were used to examine the changes in the secondary structure of the ovomucoid treated by different temperatures.

[Study of the effect of temperature on the conformation of ovotransferrin by two-dimensional infrared correlation spectroscopy].

The conformation changes of Apo-Ovotransferrin and Holo-Ovotransferrin were studied with the heat treatment 25-95 degrees C by using Fourier transform infrared spectroscopy (FTIR) and two-dimensional correlation spectroscopy analyzer. The results of one-dimensional infrared spectroscopy showed that with the increase in temperature, the peak at 3 300 cm(-1) of Apo-Ovo-transferrin shifted more than that of Holo-Ovotransferrin. The peak at 3 300 cm(-1) derived from stretching vibrations of N-H and O-H indicates that iron-binding enhanced the role of hydrogen bonds and resistance to heat.

[The detection of hatching eggs prior to incubation by the near infrared spectrum].

The detection of the infertile eggs and fertile eggs by the near infrared diffuse reflectance spectra was proposed. Models based on different band regions range, different principal component numbers and the different spectral pre-processing methods were compared and the optimal calibration model was established. The results show that qualitative forecasting model of hatching eggs is established by Mahalanobis Distance, which is with band regions range being 4 119.

[Investigation of interaction between riboflavin and riboflavin binding protein by fluorescence spectroscopy].

The interaction between riboflavin and egg white riboflavin binding protein (RBP) was investigated using fluorescence spectroscopy. The binding mode, binding constants, thermodynamic parameters between riboflavin and RBP and energy transfer were studied. The experimental results showed that riboflavin has the ability to quench the intrinsic fluorescence of RBP because of a complex formed, and the quenching mechanism is static quenching.

[Effect of S-configuration transformation on the microstructure of ovalbumin].

The effect of S-configuration transformation on the microstructure of ovalbumin was studied by CD spectra, XRD spectra, ANS fluorescence probe emission spectra and UV absorption spectra. CD spectra was used to examine the changes in the secondary structure of the ovalbumin during S-ovalbumin information process. When the induction time was prolonged, the mutual transformation between alpha-helix, beta-sheet, beta-turn and the random coil was observed, and the orderliness of the secondary structure was increased with alpha-helix decreasing slightly and beta-sheet increasing correspondingly.

[A facile colloid aqueous method for synthesis of water soluble ZnSe quantum dots with high fluorescence and stability characterization].

Highly fluorescent and stable ZnSe quantum dots were synthesized by a facile colloid aqueous phase route. It overcame the defects such as instability and low quantum yields of the quantum dots synthesized by early aqueous phase route. Optimum conditions were found.

[Second derivative FTIR spectroscopic study of Bacillus cereus].

Some particular cell components of intact Bacillus cereus could be detected and identified by Fourier transform infrared spectroscopy (FTIR). FTIR were collected directly, then the FTIR spectra of the samples were converted into second derivative spectra. Typical marker bands were used to identify these bacterial cell components such as capsules, endospores or storage materials.