In order to evaluate the effect of lactic acid (LA)-assisted low-temperature plasma on the preservation of yellow-feathered broiler carcass, single factor experiments and response surface methodology were used to investigate total viable count (TVC), coliform count (CC) and fat oxidation value as a function of three variables, namely LA concentration (V/V), discharge voltage, and discharge time. Microbiological, physicochemical, and quality indicators of chicken were determined during storage after sterilization under optimized conditions. The results showed that the optimal sterilization parameters were LA concentration of 2.0%, discharge voltage of 150 kV, and discharge time of 115 s. Under these conditions, the TVC and CC on the surface of chicken and its fat oxidation value were 3.02, 1.00 (lg(CFU/g)) and 0.58 mg/kg, respectively. On the 7th day of storage, the inhibitory effects of LA-assisted low-temperature plasma on TVC and CC increased by 26.75% and 19.72% compared with those of LA, by 34.51% and 24.87% compared with those of low-temperature plasma, respectively, and the combination decreased the total volatile basic nitrogen (TVB-N) content by 27.35% and 12.25% compared with single treatments with LA and low-temperature plasma, respectively. In addition, the combination treatment delayed the increase in pH of chicken during storage, improved the texture, and significantly slowed down the deterioration of sensory quality (P < 0.05). Low-temperature plasma treatment increased the fat oxidation value at the early stage (from day 1 to 3) of storage, but did not have a significant impact on the sensory evaluation of meat in terms of odor or color. Overall, LA combined with low-temperature plasma was more effective in preserving yellow-feathered broiler carcass than either alone.

In order to reveal the unique texture characteristics of Tibetan chicken breast meat and their correlation with chemical composition and microstructure, this study tested the shear force, texture profile analysis (TPA) parameters and stress relaxation characteristics of breast meat from Tibetan chicken, and Xueshan chicken, spent hen and white feathered broilers with the same age or body mass as Tibetan chicken, and it also analyzed the correlation between the texture properties and chemical properties (moisture content, fat content, protein content, collagen content, and pH) as well as histological characteristics (muscle fiber diameter and density). Meanwhile, partial least squares regression (PLSR) was used to explore the significant factors that affect the texture characteristics of chicken meat. Our results indicated that PLSR could quantify various chemical indices related to chicken meat texture as comprehensive quality indices. Shear force was more suitable to establish a model to predict chicken meat texture properties. The R_X² and R_Y² of the proposed model were 0.621 and 0.739, respectively, suggesting good fitness. The Q_cum² of the model was above 0.6, showing acceptable prediction accuracy. The loading plot showed that shear force was positively correlated with pH, total collagen content and muscle fiber diameter significantly (P < 0.05), but was negatively correlated with fat content, muscle fiber density, soluble collagen content and collagen solubility significantly (P < 0.05). Collagen solubility, muscle fiber density, soluble collagen content and muscle fiber diameter all contributed significantly to the model. These findings provide data support for revealing the unique “chewiness” of Tibetan chicken meat from the perspective of its texture, and a theoretical basis to enrich research on meat mechanical properties.

In order to investigate the effect of low-temperature air cooling on the postmortem energy metabolism and meat quality of yellow-feathered broilers during mixed cooling (first water cooling and then air cooling), 85-day-old broilers were slaughtered and divided into three groups: treatment (water cooling at 0—4 ℃ followed by air cooling at -8, -18, -25 or -31 ℃), control (traditional water cooling at 0—4 ℃) and traditional mixed cooling (water cooling at 0—4 ℃ followed by air cooling at 0—4 ℃) groups. Finally, all carcasses were cooled to an internal temperature of 4 ℃, and the optimal air cooling temperature was determined by measuring cooling rate, pH, energy metabolism and quality indexes. The results showed that the cooling time of air cooling at -25 and -31 ℃ was 2537 and 2272 s, respectively, which was shortened by 27.78% and 35.33% compared with the traditional water cooling and by 51.87% and 56.90% compared with the traditional mixed cooling, respectively. Air cooling at -25 and -31 ℃ delayed the decrease in pH, reduced the drip loss and cooking loss of broiler breast muscle, significantly increased the shear force and the content of immobilized water compared with the control group (P < 0.05). Compared with the other groups, the activities of muscle hexokinases, phosphate-3-phosphate dehydrogenase and lactate dehydrogenase in the air cooling treatments at -25 and -31 ℃ were lower, and the consumptions of adenosine triphosphate (ATP) and glycogen, the production of lactic acid and adenosine monophosphate (AMP) and AMP/ATP ratio were the smallest (P < 0.05). The above findings showed that air cooling at -25 and -31 ℃ significantly inhibited the rate of anaerobic glycolysis during the early postmortem period in chicken meat, delayed the rate of pH decline, and effectively improved muscle water retention. From the perspective of industrial energy saving, -25 ℃ is determined as the best temperature for air cooling treatment.

Spicy taste have been utilized in the food industry as appetizers, stomachics, and beverages and in the health sector to alleviate high cholesterol and hypertension. However, an understanding of  neural mechanisms and cognitive processes associated with spicy diets remains limited due to the lack of instruments that directly monitoring the brain’s reaction to spicy sensations.  This study aimed to examine the neural responses of participants to oral capsaicin solutions through functional near-infrared spectroscopy and reveal distinct neural activation patterns associated with  spiciness induction and relief phases. Results showed that the perception of spiciness is a dynamic process, and significant differences in sensory intensity and emotion were observed between the phases. The prefrontal regions of the brain were activated during spicy flavor perception and presented clear lateralization effects.  Further spatial localization results indicated that the orbitofrontal, dorsolateral prefrontal, and ventral lateral prefrontal cortices were the main causes of difference in activation among the phases. In addition, correlational analyses indicated that spicy flavor perception activated cortical areas related to emotion and reward processing. Overall, this research enhances our understanding of the neural mechanisms underlying addiction to spicy food and may be useful in the development of food on the basis of consumers’ preferences and behavioral responses.

As a serious threat to the broiler industry, woody breast (WB) requires precise classification that is theoretically aligned with the advantage of bioelectrical impedance detection. This research used normal chicken breast (NORM) and three levels of WB condition, namely, mild, moderate and severe (SEV), based on sensory evaluation. The basic objective quality indicators and impedance characteristics of the samples were detected, and then the various levels of WB were categorized by model-classification approach. At a consistent frequency, the impedance amplitude of samples decreased with increased WB level. Significant differences in the absolute value of the phase angle existed among different levels of WB. The increase in WB level led to a considerable increase in intracellular resistance (R_i) and in the characteristic frequency (f_c). However, four other indices including the radius of Cole-Cole curve arc, the extracellular resistance (R_e), the polarization coefficient (K), and the relaxation factor (α) substantially dropped with increased WB level. The accuracy of SEV training, NORM and SEV test samples achieved a perfect score of 100% according to the partial least squares (PLS) prediction model. The PLS model also exhibited an overall accuracy of 91.70% for training samples compared with the value of 88.35% from limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) deep-learning prediction model. However, the L-BFGS model achieved a higher overall correct rate for test samples (90.00%) than PLS model (80.00%). These results provided valuable information for the classification of WB based on the characteristics of bioelectrical impedance.