List of ingredients:
1. The ingredients are not fresh or there are too many impurities, which leads to the contamination of natto strains. It is recommended to choose fresh and clean ingredients and pay attention to the hygiene of storage and use.
2. Improper proportion of ingredients may lead to incomplete or excessive fermentation of natto, resulting in peculiar smell. It is recommended to make it according to the correct proportion of ingredients and ensure that all materials are fully mixed.
As far as production steps are concerned:
1. Improper control of fermentation temperature and time may lead to excessive or insufficient fermentation of natto and odor. It is suggested that fermentation should be carried out at suitable temperature and time, and attention should be paid to observation and control.
2. natto machine or containers are not thoroughly cleaned, which may lead to mixed bacteria pollution and odor. It is recommended to thoroughly clean the natto machine or container before use to keep it clean and hygienic.
In short, there are many reasons why homemade natto tastes bad. It is necessary to pay attention to the freshness and hygiene of ingredients, as well as the control of temperature, time and container during the production process. If the smell still appears, you can try to adjust the production steps or change the strain to make it again.