YenzoWhat is E231 (orthophenyl phenol)?
It is ortho-phenylphenol, also called 2-phenylphenol or OPP; the JECFA record lists it as a preservative and flavouring agent. Directive 95/2/EC of the EU listed E231 as a preservative in and on citrus fruits.
E231Orthophenyl phenol
E231 is ortho-phenylphenol (2-phenylphenol, OPP), a preservative. In 2003 the EU moved E230, E231 and E232 out of the food additives directive because they fall under the legal definition of plant protection products.
Did you know? According to the 1999 JMPR, 2-phenylphenol and its sodium salt were first evaluated by the 1962 JECFA for "post-harvest treatment of fruits and vegetables to protect against microbial damage during storage and distribution in commerce".
- Code
- E231 · INS 231
- Group
- Preservative
- ADI
- 0.4 mg/kg bw (JMPR 1999 (2-phenylphenol))
In Vietnam✓ PermittedOn the list of permitted additives — Circular 24/2019, Appendix 1
Risk level on the Yenzo Scalemoderate?Based on a regulator's decision
The evaluators disagree. EU (2003) withdrew it from the list of substances permitted in food, while JECFA (1964) keeps an ADI for it.
How E231 appears on labels
IngredientsIllustrative example
Wheat flour, vegetable oil, salt, sugar, preservative (231), dried onion and garlic, pepper, natural colour (160a).
preservative (231)preservative 231E231INS 231On Vietnamese labels: Ortho-phenylphenol
Questions about orthophenyl phenol
Is 2-phenylphenol harmful?
In 1999 JMPR allocated an ADI of 0–0.4 mg/kg body weight for 2-phenylphenol. Also according to JMPR 1999, estimated intake from residues in all five GEMS/Food regional diets was 0% of the ADI. The EU moved E231 to plant protection products on a legal definition.
“The Meeting concluded that the intake of residues of 2-phenylphenol resulting from its uses that have been considered by the JMPR is unlikely to present a public health concern.”
FAO/WHO JMPR 1999: 2-Phenylphenol and its sodium salt (056)
Is E231 permitted in Vietnam?
Yes. Ortho-phenylphenol (INS 231) is listed in Appendix 1 of Circular 24/2019/TT-BYT, the list of additives permitted in food, as a preservative.
Other preservatives
E227Calcium hydrogen sulphitehighE228Potassium hydrogen sulphitehighE230Biphenyl (diphenyl)highE232Sodium orthophenyl phenolmoderateE234Nisinvery lowE235Natamycinlow
See all preservatives →Updated 21 October 2026
Sources (5)
- Regulator's decision. Regulation (EC) No 1333/2008 on food additives, Annex II (Union list of food additives approved for use in foods), https://eur-lex.europa.eu/eli/reg/2008/1333/oj: not in the Union list, moved to the plant protection rules (Directive 2003/114/EC). JECFA: 8th meeting (1964): ADI allocated. https://apps.who.int/food-additives-contaminants-jecfa-database/Home/Chemical/3846
- JECFA Evaluations: 2-PHENYLPHENOL (INS 231), INCHEM
- Thông tư 24/2019/TT-BYT (văn bản hợp nhất 09/VBHN-BYT), Phụ lục 1
- FAO/WHO JMPR 1999: 2-Phenylphenol and its sodium salt (056)
- Directive 2003/114/EC of the European Parliament and of the Council of 22 December 2003 amending Directive 95/2/EC on food additives other than colours and sweeteners