ST reader Vivian Tan wrote in to say that her in-laws recently thawed a piece of cod fish to cook porridge for her eight-month-old baby.
She added that her in-laws intended to thaw the fish, divide it into smaller pieces, then use one piece and re-freeze the rest.
She objected to this as she thought it was not advisable to thaw raw meat more than once.
Her in-laws said that all fish are frozen and then thawed to be sold in the supermarket.
She wanted to know the practice by fishmongers/ butchers and supermarkets, and whether fish and meat can be frozen again after being bought from the market.
In particular, she asked for the Agri-Food and Veterinary Authority's (AVA) take on this and the risk of food poisoning or food turning bad with this practice.
Mind&Body editor Ng Wan Ching finds an answer.
Any raw or cooked food that has been thawed can be refrozen as long as it was thawed properly in the refrigerator and not on the counter, and has not spoiled.
That is the view of a registered dietitian with the United States Department of Agriculture's Food Safety and Inspection Service.
This applies to raw meat, poultry and seafood.
The key is in how the frozen food was thawed.
It should be thawed in the refrigerator, and never by placing it on the counter at room temperature or by running it under warm tap water.
This is because bacteria like a warm environment and multiply rapidly at room temperature.
You should also not allow thawed raw meat, poultry and seafood to sit in the fridge for too long before refreezing it because it can spoil in the refrigerator too.
The signs of spoiled food include it giving off a bad or "off" smell, and it may be sticky or slimy.
Ths Straits Times understands that imported seafood, including fish, comes in various forms - live, chilled and frozen.
The consumer can check with the fishmonger whether the fish he has for sale has been thawed before.
Likewise, the consumer can also check at the supermarkets whether the fish, meat and seafood products were thawed before being put up for sale.
The AVA advises consumers not to thaw and re-freeze seafood and meat.
Thawing and re-freezing will affect the quality of the product, said a spokesman from AVA.
Bacteria will also start to multiply once seafood/meat is thawed, which may lead to spoilage or cause food poisoning.
After purchasing frozen seafood and meat, consumers should portion them out into suitable servings size before storage.
This good food safety practice will help consumers avoid the need to re-freeze any unused portion of thawed seafood or meat, said the AVA spokesman.
This article was first published on Oct 10, 2016.
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