Proximate Analysis and Safety Profile of Farmed Edible Bird’s Nest in Malaysia and Its Effect on Cancer Cells

Abstract

Edible bird’s nest (EBN) which is solidified swiftlet’s saliva contains high nutritional value. It is widely consumed in countries like Malaysia, Indonesia, and Thailand. However, previous proximate analysis of Malaysia EBN was not representative of all the regions in Malaysia. In recent years, safety issues such as high nitrate and nitrite contents, presence of heavy metal, adulteration, fungal infection, and cancer cell stimulation were associated with EBN. Hence, this study aimed to determine the proximate analysis, safety profile during normal weather and hazy periods, and its effect on cancer cells stimulation in Malaysia-farmed EBN. Seven raw cleaned EBN samples were sourced from 6 different regions in Malaysia. Proximate analysis and safety profile were performed using official AOCA methods and Malaysian Standard. High protein (53.03–56.37%) and carbohydrate content (27.97–31.68%) with an acceptable level of moisture (10.8–14.04%) and ash (2.22–3.38%) were reported. A good safety profile was obtained with low nitrite and nitrate levels, with undetectable heavy metals and no significant growth of pathogenic microorganism except mould. Epidermal growth factor was detected but below the quantification level with the chicken EGF ELISA kit. The microculture tetrazolium (MTT) assay was performed for growth stimulation assessment comparing human EGF and EBN. There was no significant cell growth observed in cancer cells after EBN treatment. In conclusion, EBN Malaysia has a good nutritional profile, free of heavy metals, and an acceptable level of nitrate, nitrite, and microorganism profile except for mould contents. Furthermore, the in vitro study indicated that EBN was not associated with cancer cell growth.

The Authentication and Grading of Edible Bird’s Nest by Metabolite, Nutritional, and Mineral Profiling

“…The proximate composition of different shaped EBN, which are half cup and stripe-shaped, is shown in Table 3 . This present finding of proximate composition was in the range of the other reported literature [ 15 , 35 ], with protein being the major content, followed by carbohydrate, moisture, and ash, while no fat was detected (lower than the limit of detection, LOD). Interestingly, fiber was found to be present in both EBN.…”

“…Moisture content found in the half cup and stripe-shaped EBN was 15.92 ± 0.08% and 19.51 ± 0.04%, respectively, which was relatively high compared with other studies, ranging from 7.50-14.00% [15,35]. However, another study had a similar range of moisture content as reported in this study (17.8-24.3%) [39].…”

Potential Residual Contaminants in Edible Bird's Nest

“…A proper cleaning process can reduce the nitrite and nitrate concentrations in EBNs (Chan et al, 2013;Hamzah et al, 2013). There are only limited studies (Quek et al, 2018;Tan et al, 2020) comparing the levels of nitrite and nitrate in house/farmed EBNs from different regions. Most studies compared between houses and cave/wild EBNs.…”

“…Although the nitrite and nitrate in the cave EBNs are significantly higher than the house EBNs on average, it can be seen from the Table 2 that the readings between the samples are widely distributed and the standard deviation value is high, especially in the cave EBNs. These nitrite and nitrate changes may be attributed to different cave and swiftlet farm environments, such as humidity, pH and climate; age of EBN when harvesting (harvesting time); contamination during harvest and the cleaning processes of the collected EBNs may all cause the different concentrations of nitrate and nitrate levels ( Paydar et al, 2013 ; Tan et al, 2020 ). The good management of the swiftlet houses, such as the frequent removal of swiftlet guano while the guano of the cave is left in the cave and not cleaned may contribute to lower nitrite level in the house nests.…”

“…The guano can produce nitrite through fermentation (to be discussed later). In addition, good ventilation design of the swiftlet houses also helps to reduce the bacterial anaerobic fermentation process, thereby reducing the concentration of nitrite ( Quek et al, 2015 ; Tan et al, 2020 ). Therefore, the management and design of the swiftlet houses results in a relatively low concentration of nitrite and nitrate in the house nests compared to the cave nests.…”