Coconut water is sterile in the interior cavity of the coconut fruit. However, once the coconut is opened and repackaged, the coconut water beverage may become a breeding ground for bacteria and fungi, leading to the production of harmful mycotoxins. This study aimed to detect the usage of preservatives and sweeteners, also the levels of the common carcinogenic contaminant benzo[a]pyrene and harmful mycotoxins in bottled coconut water sold on the market. By using national standard methods, no preservative such as benzoic acid and sorbic acid, no sweetener sodium saccharin, and no contaminant benzo[a]pyrene were detected in this batch of coconut water beverages. This study also investigated the level of mycotoxins in bottled coconut water stored at low temperatures (4-8 ℃) for 21 days. No zearalenone (ZEN) or deoxynivalenol (DON) was detected in the coconut water stored at 4-8 ℃ for 21 days. During monitoring, the response signal for aflatoxin B1 (AFT B1) in one of the samples had an increasing trend with prolonged storage time but the level did not exceed the quantitative limit specified in the national standard method. Electron microscope observation of the bottled coconut water stored at low temperatures revealed a large number of moving microorganisms in 1-3 days, with the aerobic plate count increasing exponentially. After 21 days of low-temperature storage, infrared spectra showed new characteristic absorption peaks, indicating that the coconut water had undergone qualitative changes. It is recommended that bottled coconut water from freshly cut coconuts should be consumed on the same day.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |