Pork bundle

Aroma Development in Chinese Fried Pork Bundle... 

Traditionally pork bundle is homemade. In this study, muscle of Rectus femoris was sliced into 20 x 10 x 10 cm3 cubes and boiled in water (100°C) for 1.5 hours to denature the muscle protein. When... 

The average temperature of the pork in the frying pan was about 80°C. A period of 70-80 minutes was needed to remove nearly 75% water, and the average final water activity was 0.70. The partially dried and disintegrated pork bundle was further fried in the same frying pan to form the desired color, flavor and mouthfeel. In the final frying stage, wheat flour was added to absorb lard and coat the surface. 

Model systems composed of the seasoned pork bundle, sucrose and lard were used to investigate the effect of the frying temperature and lard content on flavor and color development in Chinese fried pork bundle. Seasoned pork bundles were prepared as described previously, except superheated steam was used to provide the various heating temperatures following the designs of Box and Behnken (1). 

As shown in Figure 2, the raw meaty odor of pork bundles decreased as the heating temperature increased, while increases in lard content had no significant effect. A possible explanation is that the raw meaty odor was covered by the flavor formed during heating. 

Frying temperature was found to be the crlterial parameter that determined the flavor quality in Chinese pork bundle. Cooked meat aroma increased as the heating temperature varied from 134°C to 172°C., as shown in Figure 3. Below 130°C neither cooked meat aroma nor brown color developed. Slightly higher temperatures have been reported for the optimum flavor formation in fried potato chips at 180°C (2), and roasted beans at 200°C (3). 

Figure 1. Development of redness and aroma during the frying of pork bundle.

Figure 2. The effect of temperature and lard content on the raw meat aroma of Chinese fried pork bundle.

Table I. Amino Acid Compositions in Chinese Fried Pork Bundles...

Amino Acid Pork Bundle Seasoned Fried... 

The basic fraction of the volatiles identified in the fried pork bundle contained 16 alkylpryazines. Among them, methylpyrazine (nutty, roasted), 2,5-dimethylpyrazine (grilled chicken, roasted peanut), 2,6-dimethylpyrazine (ether-like), 2,3,5-trimethylpyrazine (nutty, roasted) and 2-ethyl-6-methylpyrazine (grassy) were predominant. The combination of these alkylpyrazines may cause the characteristic cooked meat aroma of Chinese fried pork bundle. Quantitative analyses showed that alkylpyrazine formed during the final frying stages, as shown in Table II. 

FIG. 1. Drying rate curve for heated pork muscle bundle. Drying rate curves were determined at a dry bulb temperature (Tab) of 40°C, a wet bulb temperature (Twb) of 35°C, and an air velocity (V) of 1.0 m/sec. The specified time in minutes for each curve (0,10,20, and 30 min) represents the tumbling time for the heated muscle bundles before the determination. Source Chang et al. (1991). Reprinted with kind permission from Elsevier Science Ltd. 

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