Is rice with weevils safe to eat?

Rice weevils are a type of beetle that occur mainly in the tropics. Small in size, they are found in crops in the field before harvest, but usually only become visible some time later, usually after processing. Signs of rice weevils include round holes in rice kernels, and grains which feel damp, due to the increase in moisture levels.

In many countries, rice weevils occasionally present themselves in rice stocks and smaller batches purchased by consumers. This is no different in Singapore. Far from tossing out the rice, here’s what can be done and how to prevent weevils from infesting your rice in future. 

Protecting rice from rice weevils: What can importers and warehouse operators do?

While weevils are not food safety threats, they are a sign of poor storage practices and can be avoided. At the same time, good storage and handling practices also help ensure the overall safety and quality of the rice. These practices include:

1. Ensuring proper storage conditions for rice

• Ensure humidity levels are kept low to prevent mould and spoilage

• Ensure low temperatures to reduce oxidation (rancidity) and the growth of pests and mould

2. Implementing good pest management practices

• Conduct weekly checks for pests: If pests are found, treat the grain (e.g. freeze them) to kill the pests

• Conduct thorough cleaning of premises to get rid of insects, especially those that may be hiding in crevices

• Reduce availability of loose grains and other food that may attract pests

• Install perimeter pest control measures (e.g. traps) around the warehouse

• Isolate infested sections for treatment

3. Following Good Manufacturing Practices, such as packing rice immediately after processing

Weevils in rice bought by consumers: To toss the rice out?

While good storage and handling practices by importers and warehouse operators can keep rice weevils at bay, consumers may still encounter weevils in rice that they have purchased from time to time. As weevils do not compromise the safety of the rice, consumers need not throw the rice away if there are weevils present. They can simply remove the weevils from the rice during washing and before cooking.

If the bag of rice is infested with weevils, place small batches of the rice on a baking pan with a baking sheet. Bake the rice at 140F or 60^oC for 20 minutes, then remove it and let it cool. Check for weevils and remove them by hand or sieve. Thereafter, place the rice in a fresh air-tight container. Do not place it back in its original container or bag as there could be remnants of the infestation.[1]

Consumers, too, can play a part in reducing instances of weevils in their rice by ensuring the safety and quality of the grains. Here are some tips:

1. Store rice in a tightly sealed container and in a cool and dry place

2. Buy rice in smaller quantities if your typical consumption of rice is low

3. Only open the rice pack when needed, and do not open multiple packs at a time. Consume the opened pack of rice within a month

4. If there is space, keep the rice in the refrigerator. This will help preserve the quality of the rice and prevent insects from infesting it

5. Once you have used up a container of rice, wash and dry the container used to store rice before re-filling it with a new pack of rice

6. Check the rice at home regularly to check for weevils. If weevils are present, quickly remove the weevils and try to consume the remaining stock of rice quickly