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Summary: In this study, the effect of combined preheating time (2, 5, and 10 min) and extraction medium pH (2.5, 3.5, and 4.5) on total monomeric anthocyanin yield, and removal of off‐odour in red radish anthocyanins were evaluated. The tentative anthocyanin identification showed twelve pelargonidin anthocyanins, and only nine were identified in samples preheated for 10 min. Sample preheated for 10 min and extracted at pH 4.5 showed lower the anthocyanin yield (98.02 mg/100 g, FW), lighter colour and higher percentage polymeric colour compared with that preheated for 2 min and extracted at pH 2.5. However, prolonged preheating time (10 min) significantly reduced myrosinase enzyme activity by 73%. Additionally, results showed that preheating time and extraction medium pH have negative and significant effect on the total monomeric anthocyanin yield, while they showed positive and negative significant effect on the total glucosinolate degradation. Furthermore, the sensory evaluation results revealed no significant difference in radish odour for samples preheated for 2 and 5 min followed by anthocyanin extraction in pH 2.5 medium. It might therefore be concluded that the combination of moderated preheating treatment time (≤5 min) and lower extraction medium pH could be effective to reduce the off‐odour characteristics and maintaining high yield and stable red radish pigment. [ABSTRACT FROM AUTHOR]

The effect of processing conditions (heating temperature, reaction time, and pH) and ingredients of beef flavor system (including enzymatic tallow hydrolysate, DL-methionine, L-cysteine, glucose, and D-xylose) on 3-monochloro-1, 2-propanediol (3-MCPD) esters concentration, and sensory characteristics of beef flavors are investigated. The results indicates that DL-methionine and L-cysteine had similar effects on the content of 3-MCPD esters, promoting their formation at low concentration, whereas, reducing them when added at high concentration. 3-MCPD esters concentration increased with increasing enzymatic tallow hydrolysate and D-xylose concentration. However, the addition of glucose has no significant effect on 3-MCPD esters concentration. Considering 3-MCPD esters concentration and sensory characteristics, the optimal addition of flavor precursors is finally selected as: Enzymatically hydrolyzed tallow (10%), L-cysteine (1.2%), DL-methionine (1.2%), glucose (1%), and D-xylose (0.5%). In addition, 3-MCPD esters concentration is also strongly dependent on heating temperature, reaction time, and pH. In conclusion, beef flavor is prepared using the optimal concentrations of flavor precursors and heated at 110 °C with initial pH 7.0 for 100 min. Practical Application: This study provides a promising way of controlling the formation of 3-MCPD esters without changing the flavor quality of savory flavors. It promotes the food safety control technology of savory flavoring from passive defense to active forewarning. Also, it provides theoretical guidance and technical support for the sustainable and healthy development of savory flavoring industry. In this study the effect of processing conditions and ingredients on 3-MCPD esters concentration and sensory characteristics are evaluated. It can provide references for the reduction 3-MCPD esters without changing its quality during beef flavor processing. [ABSTRACT FROM AUTHOR]

The effect of heating parameters on pork bone soup flavor generation in electrical stewpot was investigated. Four sensory attributes including meaty, fatty, kokumi and off-flavor were used to evaluate the sensory characteristics of different pork bone soups. Twenty-nine odor active compounds were identified by direct-time intensity method of gas chromatography-mass spectrometry/olfactometry (GC-MS/O). Only eleven of them were detected in both traditional clay and commercial electrical stewpots. One of the electrical stewpot samples showed good sensory characteristics compared with other samples and its corresponding heating parameters were as follows: heating rate of 2.419°C/min, constant temperature time of 20 min, low temperature of 80°C and its holding time of 50 min. Correlation analysis between sensory attributes and odor active compounds through Partial Least Squares Regression (PLSR) revealed that hexanal, octanal, 6-methyl-5-hepten-2-one, 2-nonanone, decanal, benzaldehyde, (E)-2-nonenal had significant correlation with the sensory attributes. [ABSTRACT FROM AUTHOR]