A bulletin for the Australian Food Industry February 2001
Contents: BSE Inquiry Report | Airborne transmission of food related viruses | Chloropropanols in food | Processing and distribution of cook-chill foods
Chloropropanols in food
Chloropropanols occur at low levels in many foods or food ingredients as a result of processing or storage conditions. At least two of the group, 3-monochloropropane-1, 2-diol (3-MCPD) and 2 3-dichloro-2-propanol (1,3-DCP), are considered potential carcinogens and hence the impetus to reduce their levels in foods to the lowest levels practicable.
The Codex Committee on Food Additives and Contaminants
will consider a position paper on chloropropanols 
which has
been prepared by the United Kingdom with assistance from
Canada and the United States and distributed widely for
comment. Each of these countries sets or is about to set guide-lines
or regulations for these components in foods. In the case
of the UK, they will follow a European Commission proposal.
In the summary of the position paper, it is noted that chloropropanol contamination is a food safety issue that has international implications and therefore a harmonised approach to control chloropropanol levels in food is required to protect consumers. The Joint FAO/WHO Expert Committee on Food Additives will consider chloropropanols in June 2001 with a view to establishing a provisional tolerable daily intake for these contaminants. This will pave the way for the setting of upper limits in foods which should receive international acceptance. At the moment different countries have set different limits.
3-MCPD is a well established contaminant of acid hydrolysed vegetable protein (acid HVP), a savory ingredient in stock cubes, soups, prepared meals and snack foods. It is found in a range of other foods and ingredients most notably in soy sauce.
The procedure used to manufacture acid HVP can result in the formation of both 3-MCPD and 1, 3-DCP. Most acid HVP is produced using hydrochloric acid. 3-MCPD is formed as a result of the high temperature chlorination of fats present in the protein starting materials. Surveys carried out by the UK government in 1990 and 1992 showed levels of 3-MCPD of up to 100 mg/kg were quite common at that time in acid HVP. Following advice from the UK government to reduce the level of 3-MCPD and 2,3-DCP to the lowest practicable level, manufacturers of acid HVP modified their process. A follow up survey in 1999 (MAFF Food Surveillance Information Sheet No. 181. June 1999) showed that levels of these contaminants had declined since the earlier investigations but the results for a number of samples were high relative to the limit recommended (0.01 mg/kg).
In 1999 the UK Government also conducted a survey of 40 samples of soy sauce and similar products to determine the levels of 3-MCPD. Two-thirds of the samples contained 3-MCPD at levels very close to or below 0.01 mg/kg. However, the remaining samples contained levels above 0.01 mg/kg, the highest being 30mg/kg. (MAFF Food Surveillance Information Sheet, No. 187, September 1999).
The products examined were imported from China and Hong Kong, Taiwan, Singapore and the Philippines.
Chloropropanols may also be found in trace quantities in some other foods but these are not seen as significant contributors to the dietary intake. Hydrolysed vegetable protein and soy sauces are also of course used in relatively small quantities.
Food Science Australia
PO Box 52, North Ryde 1670. Tel +61 2 9490 8397 Fax +61 2 9490 8499
Email enquiries@csiro.au