EFFECTS OF COOKING CONDITIONS ON SENSORY CHARACTERISTICS OF RED-COOKED BEEF FLAVOR AND IDENTIFICATION OF THE FLAVOR COMPOUNDS
Red-cooked beef is a very popular food in China. The sensory characteristics and flavor compounds of red-cooked beef were investigated in the present study. Through the single-factor analysis of sensory score, it was changed under different cooking conditions, including pH value, cooking temperature and time. Response surface methodology and quantitative descriptive analysis were applied to investigate the effects of pH value, cooking temperature and time on the sensory score of red-cooked beef flavor. A suitable range for each factor (5–8 for pH value, 90–110C for cooking temperature and 1.5–2.5 h for cooking time) was chosen for building a mathematical regressive model. The mathematical model representing the sensory score of red-cooked beef flavor as a function of the independent variables within the region under investigation was expressed by the equation as follows: Y = 76.86 − 0.51X1 − 4.14X2 + 0.47X3 + 0.054X1X2 − 0.041X1X3 + 0.049X2X3 − 4.83 , where Y was the sensory score, and X1, X2 and X3 were the coded variables of pH value, cooking temperature and time, respectively. The optimal conditions to obtain the highest sensory score were 6.42 of pH value, 97.4C and 2.05 h, respectively. Under these optimal conditions, the experimental value agreed with the predicted one by analysis ofvariance. The potent flavor compounds of red-cooked beef were extracted by headspace solid phase micro-extraction technique, and 99 volatile compounds were detected using gas chromatography-mass spectrometry, which consisted of 23 aldehydes, 12 ketones, 10 esters, 11 alcohols, 15 carboxylic acids, 2 sulfur-containing compounds, 9 heterocyclic compounds, 12 alkanes and 5 alkenes. PRACTICAL APPLICATIONS
Response surface methodology is a statistical method that has shown significant advantages in application of food process. In the present study, this methodology was employed to investigate the effects of pH value, cooking temperature and time on the sensory characteristics of red-cooked beef flavor. A mathematical regressive model was built with a good fitness, and the optimal cooking conditions were predicted. The flavor compounds of red-cooked beef cooked under the optimal conditions were identified by gas chromatography-mass spectrometry. Twenty-three aldehydes, 12 ketones, 10 esters, 11 alcohols, 15 carboxylic acids, 2 sulfur-containing compounds, 9 heterocyclic compounds, 12 alkanes and 5 alkenes were found contributing to the red-cooked beef flavor.
Document Type: Research Article
Affiliations: 1: College of Light Industry and Food SciencesSouth China University of TechnologyGuangzhou 510640, China 2: Guangdong H-BIO Biotechnology Co., Ltd.Guangzhou 510665, China 3: South China Botanical GardenChinese Academy of SciencesGuangzhou Leyiju 510650, China
Publication date: 01 February 2008