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Salted egg is easily preserved of egg products. The making process was added liquid smoke. Therefore, the objective was to determine chemical characteristics (yolk index, oil exudation and salt content) of duck egg salted. Completely Randomized Design (CRD) was used throughout the research. They were run triplicate with differences concentration of liquid smoke (control, 1%, and 1.25%). They were differences salting time process (0, 1, 2, 3, and 4 weeks). Yolk index of control sample were no different statically compared to that of salted egg with liquid smoke treatment (p > 0.05). Significant different of yolk index (p < 0.05) increased along with increase of salting time (4 weeks). Significant differences (p < 0.05) were found on oil exudation of control sample compared to that salted egg with presence of liquid smoke. Oil exudation of salted egg yolk increased with increasing salting time (p < 0.05) up to 4 weeks. Significant differences (p < 0.05) were obtained on the salt content of control compared to that salted egg white treatment of liquid smoke. Salt content white increased along with the increase of salting time (p < 0.05).

A novel two-step controlled basic water phase method has been developed for synthesizing size-tunable and water-soluble CdTe/Cd(OH) 2 core/shell quantum dots with high quantum yield and good stability. The size of the prepared CdTe/Cd(OH) 2 core/shell quantum dots can be easily manipulated by varying the concentrations of NaOH solution step by step. The maximal emission wavelengths of the series CdTe/Cd(OH) 2 core/shell QDs were from 513 nm to 610 nm (emission colors tuned from green to red). The CdTe/Cd(OH) 2 core/shell quantum dots not only possess high quantum yield (up to 83%) but also exhibit excellent photostability (being stable after being stored for more than 2 months). The CdTe/Cd(OH) 2 core/shell quantum dots were characterized by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray powder diffraction spectrometry, ultraviolet–visible spectrometry and fluorescence spectrometry. The water-soluble nature of the CdTe/Cd(OH) 2 core/shell quantum dots offers great potentiality for their chemical and biological applications. This method is easily controlled, low-cost and reproducible. So it is possible to extend this approach to the preparation of other size-tunable inorganic metal hydroxide capped core/shell quantum dots.

The characteristic of Listeria monocytogenes' pyrolysis product was found by fingerprint analysis of high resolution pyrolysis gas chromatography and mass spectrometry (HRPGC/MS), which hold a great potential to rapidly detect L. monocytogenes with the application of selected ion monitoring (SIM). Food products (beef and milk) contaminated by L. monocytogenes and uncontaminated were evaluated. The retention time of the characteristic peak of pyrolysis product was 19.056min, the ion of m/z were 54, 98. The results showed that the peak at retention time 19.056min was detected in agricultural products that contaminated by L. monocytogenes, while the result of the uncontaminated food, there is no peak at the retention time 19.056min. Qualified by the retention time of chromatographic and mass spectrometry, it can eliminate the interference induced by different types of agricultural products. The results prove united technologies of HRPGC/MS and SIM is not only reliable, reproducible, but also a new method for rapid detecting L. monocytogenes in food products.

Near-infrared spectroscopy was used for prediction of the alkalinity in the feed liquid of processing preserved-eggs. Using the techniques of partial least square (PLS), principal component regression (PCR) and stepwise multiple linear regression (SMLR), three NIRS-based models for estimating the alkalinity were established. According to the standards of coefficient of determination (R2), root mean square error of calibration (RMSEC) and root mean square error (RMSEP), a best calibration model of PCR was achieved for the prediction of the alkalinity in the feed liquid of processing preserved-eggs. R2=0.93478, RMSEC=0.0101 and RMSEP=0.0126 by PCR, and a satisfying prediction precision was achieved. The results indicated that near infrared spectroscopy could be successfully applied for the prediction of the alkalinity in the feed liquid of processing preserved-eggs and PCR model could achieve a best prediction results.

This paper reported an electrical stimulation instrument in order to meet the tenderizing requirements for different varieties and parts of the beef. Based on pulse-width modulation (PWM), this instrument has at its core single-chip microcomputer MSP430 and H-bridge with four MOSFET. By controlling the duty cycle of the PWM/SPWM (Sinusoidal PWM) produced by single-chip microcomputer, this instrument could realise the inversion of direct current by H-bridge, thus generating different wave forms. This paper introduced the functions, operation principles, hardware and software structure of the instrument. The results showed that: The instrument was able to produce 5 types of the waveforms, namely, DC, square wave, sine wave, triangular wave and sawtooth wave. The each parameters of electrical stimulation instrument were all adjustable. The peak voltage range of each waveform was 0∼110V and frequency adjustment range was 1∼450HZ. Finally the paper concludes with an experiment whose result shows that the output of electrical stimulation parameters could achieve the tenderizing requirements with its high precision, which has provided the technical support for the beef tenderizing processing.