Novel hybrid mechanical cleaning process of raw edible bird nest using fruit based bio-enzymes

Edible bird’s nest (EBN) is made of salivary secretions from swiftlet called Aerodynamus Fuciphaga. It is consumed as a delicacy known as the “Caviar of the East” or as medicinal food in traditional Chinese medicine for health ranging from enhancing complexion, alleviating asthma, and strengthening the immune system. The tedious process of cleaning the feathers and dirt requires skilled and patient labor, since this process is time consuming due to the size of the feathers and dirt that is hardly seen. This study is conducted to test the effectiveness of using plant enzymes incorporated in a mechanical shaker to facilitate the cleaning process of EBN as quality improvement. Plant enzyme used are bromelain and papain reviewed to be the important plant-based enzyme normally used in various industries as meat tenderizer, pharmaceutical, detergents as well as in preparation of leather and wool. Since crude enzyme contain a lot of impurities, the purification of enzyme was done using Three Phase Partitioning (TPP) technique that uses ammonium sulfate and t-butanol as the medium of purification. The optimized operating condition for maximum specific enzyme activity on papain (1.1362 CDU/mg at ammonium sulfate concentration of 52.34%, t-butanol to enzyme ratio of 1.61:1.0 and at pH 6.88) and bromelain (1.8036CDU/mg at ammonium sulfate concentration of 47.5%, t-butanol to enzyme ratio of 1.5:1.0 and at pH 7.3) was predicted using the developed model with high accuracy (95% confidence level) and reproducibility. Optimization study for mechanical cleaning process of EBN using the mechanical shaker with the aid of enzyme was investigated. The effects of micro bubble time, shaking time and concentration of enzyme on the cleanliness of EBN was also investigated. Based on the OFAT studies, the optimum microbubble time was determined to be 5min, shaking time at 5min while enzyme concentration was at 5g/L. From the FTIR analysis conducted, it was observed that all samples with and without enzyme had similar trend in the fingerprint region (4000 cm-1 to 1000 cm-1). Thus showing that enzyme treated EBN does not alter the nutritional content in EBN. From SEM analysis, mites and feather strand was not visible in enzyme treated EBN. Comparison of manual cleaned EBN with papain and bromelain treated EBN shows an increase in protein content of 17.38% and 17.81% respectively and carbohydrate content of 8.56% and 10.39% respectively. Results showed that bird nest after treatment with enzyme has better quality and can replace traditional cleaning process of edible bird nest which is tedious and time consuming. It took only 10 minutes compared to 1 hour per sample using mechanical shaker incorporated with enzymes. Cleaned EBN can fetch a higher market value compared to raw edible bird nest.