Borax: An Unhealthy Caviar Additive?

Mostly used by Iranian producers of beluga caviar, does borax really pose as a health threat – especially kidney damage - when used as a food preservative in caviar packaging?


By: Ringo Bones


An overwhelming majority of caviar purists – make that beluga caviar purists – say that pasteurization ruins the taste of caviar despite of a guaranteed sanitation and extended shelf-life of the finished product. I mean pasteurization is used supposedly to perform partial sterilization of a substance – in this case caviar – at a temperature that destroys objectionable microorganisms – especially those that causes food spoilage and food poisoning - without major chemical alteration of the substance. Sadly for us caviar connoisseurs, the words ”without major chemical alteration of the substance” has enough of an effect to alter the taste of pasteurized beluga caviar. If pasteurization just won’t do, then what is the alternative?

Iranian caviar manufacturers have over the years resorted to borax – which had become their signature process – as a way to guarantee the extended shelf-life of processed caviar without the negative effects, when it comes to taste, of pasteurization. Borax is a hydrated sodium borate, often used as a cleaning agent and as a flux in soldering and welding, it is also used as a preservative. Borax - from my tongue's perspective - has a slight bitter taste, but at quantities used by Iranian caviar producers, it is far below the taste threshold of the most finicky caviar connoisseur. But is this quantity small enough not to damage the kidneys of you typical caviar connoisseur?

Iranian caviar producers add borax to the salt mix supposedly to give their caviar a “softer and sweeter finish”. Unfortunately, borax is considered an illegal food additive in the United States due to its suspected negative effects to the human kidneys. But Iranian caviar producers swear that the quantities of borax that they add to their caviar are far below the health risk threshold established by the US Environmental Protection Agency when it comes to borax ingestion. Due to the lucrative nature of the caviar trade in the United States, the US Food and Drug Administration (FDA) has recently changed its policy on adding borax to caviar. Seems like profits trumps health concerns.