Notice of Modification to the List of Permitted Food Enzymes  to Enable  the Use of Hexose Oxidase from  
Hansenula polymorpha  (B13 -HOX4 -Mut45) as a Food Enzyme in Certain Cheese, Bakery and Milk Products  
  
Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch     1 
  
Notice of Modification to the List of Permitted Food 
Enzymes  to Enable  the Use of Hexose Oxidase from 
Hansenula polymorpha  (B13 -HOX4 -Mut45) as a Food 
Enzyme in Certain Cheese, Bakery and Milk 
Products   
 
 
Notice of Modification – Lists of Permitted Food Additives  
Reference Number: [NOM/ADM -0010 ] 
 
 
 June  4, 2013   
Notice of Modification to the List of Permitted Food Enzymes  to Enable  the Use of Hexose Oxidase from  
Hansenula polymorpha  (B13 -HOX4 -Mut45) as a Food Enzyme in Certain Cheese, Bakery and Milk Products  
  
Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch     2 Summary  
 
Food additives are regulated in Canada under Marketing Authorizations  (MAs) issued by the 
Minister of Health and the Food and Drug Regulations.  Approved food additives and their 
permitted conditions of use are set out in the Lists of Permitted Food Additives  that are 
incorporated by reference in the MAs.  A petitioner can request that Health Canada approve a 
new additive or a new condition of use for  an already approved food additive by filing a food 
additive submission with the Department's Food Directorate.  Health Canada uses this premarket 
approval process to determine whether the scientific data support the safety of food additives 
when used unde r specified conditions in foods sold in Canada.  
 
Health Canada received a food additive submission seeking approval for the use of hexose 
oxidase as a food enzyme at a maximum level of use in accordance with good manufacturing 
practice in the manufacture of pizza mozzarella cheese, part -skim pizza mozzarella cheese, ultra -
heat treated (UHT) milk, and dough for bread, baking and pasta . 
 
The results of Health Canada’s evaluation of available scientific data support the safety and 
efficacy of hexose oxidase when used as set out in the table below.  Since this is a food additive 
that was not previously permitted for use in Canada, Health Canada published its  proposal, 
entitled,  Information and Consultation Document on Health Canada's Proposal to Enable the 
use of the Food Additive 'Hexose Oxidase' in pizza mozzarella cheese, part -skim pizza 
mozzarella cheese, ultra -heat treated milk, and dough for bread, bakin g and pasta , in November 
2012, requesting comments.  One comment was received  during the consultation , in which no 
objection to the proposal was expressed. Given that n o new scientific information was submitted 
to the Department during the consultation , and s ince the conclusions of the evaluation remain as  
proposed , Health Canada has modified the List of Permitted Food Enzymes  as indicated in the 
table below.  
 
Health Canada’s proposal identified the potential need for modifying the regulatory standards fo r 
the standardized foods that are covered by the proposal. It has since been determined that such 
modification will not be required at this time in order to enable the use of hexose oxidase.   
 
Modification to the List of Permitted Food Enzymes  
Item 
No. Column 1  
Additive  Column 2  
Permitted 
Source  Column 3  
Permitted in or upon  Column 4  
Maximum Level of Use 
and Other Conditions  
H.2 Hexose 
oxidase  Hansenula 
polymorpha 
(B13 -HOX4 -
Mut45)  (1)  
Bread; Flour; Whole 
wheat flour  (1) 
Good Manufacturing 
Practice  
(2)   
Unstandardized bakery 
products  (2) 
Good Manufacturing 
Practice   
Notice of Modification to the List of Permitted Food Enzymes  to Enable  the Use of Hexose Oxidase from  
Hansenula polymorpha  (B13 -HOX4 -Mut45) as a Food Enzyme in Certain Cheese, Bakery and Milk Products  
  
Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch     3 (3)  
Milk , partly skimmed 
milk, skim milk and 
sterilized milk ,  heat-
treated to at least 100°C  (3) 
Good Manufacturing 
Practice  
(4) 
Part skim pizza 
mozzarella cheese; Pizza 
mozzarella cheese  (4) 
Good Manufacturing 
Practice  
 
 
Rationale  
 
Health Canada’s Food Directorate completed a pre -market safety and efficacy assessment of 
hexose oxidase obtained from the genetically -modified production organism, Hansenula 
polymorpha (B13 -HOX4 -Mut45). This strain expresses a gene from the alga Chondrus crispus  
(Irish moss or carrageenan seaweed) that encodes hexose oxidase.  The assessment considered 
chemical, microbiological, toxicologic al, and technical aspects of hexose oxidase when  used as 
requested in the food additive submission.  
 
A safety evaluation of the potential exposure to lauryl trimethyl ammonium bromide, which is 
used in the extraction of the enzymes from the production organism, was also conducted.  
 
Based on the results of the safety assessment, Health Canada’s Food Directorate considers that 
the data support the safety of hexose oxidase from Hansenula polymorpha (B13 -HOX4 -Mut45) 
when used under the conditions of use set out in the table above.  The Department has therefo re 
enabled the use of hexose oxidase as described in the table above.  
 
Other Relevant Information  
 
Since the food additive submission requested the use of hexose oxidase  in foods that are 
standardized under the Food and Drug Regulations , the Canadian Food Inspection Agency 
(Dairy Program) and the appropriate food industry associations were consulted.  
 
 The food industry associations consulted expressed their support of the proposal to 
legally permit the use of hexose oxidase.  
 
The Canadi an Food Inspection Agency had no objections to the use of hexose oxidase in pizza 
mozzarella cheese, part -skim pizza mozzarella cheese, UHT milk, and dough for bread, baking 
and pasta. It was also noted that the Dairy Products Regulations  (Canada Agricultural Products 
Act)  list "part skim pizza mozzarella" and "pizza mozzarella" as varieties of cheese in section 
28.1, the table to which specifies maximum percentage of moi sture and minimum percentage of 
milk fat for a large variety of different cheeses.  
  
Notice of Modification to the List of Permitted Food Enzymes  to Enable  the Use of Hexose Oxidase from  
Hansenula polymorpha  (B13 -HOX4 -Mut45) as a Food Enzyme in Certain Cheese, Bakery and Milk Products  
  
Bureau of Chemical Safety, Food Directorate, Health Products and Food Branch     4 Regarding its status in other countries, hexose oxidase has GRAS (Generally Recognized as 
Safe) status for use in foods in the United States of America. It is considered acceptable for use 
in foods in  Denmark , in accordance with the guidelines for the former Scientific Committee for 
Food of the Commission of the European Communities. Hexose oxidase is listed as a processing 
aid in the Food Standards Code of Australia and N ew Zealand.  
 
Internationally, it is listed in the Inventory of Processing Aids of the Codex Committee on Food 
Additives. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has 
specifications for hexose oxidase from Chrondus crispus  expressed in Hansenula polymorpha .  
These specifications were prepared at the 63rd meeting of JECFA in 2004, at which time an 
acceptable daily intake of “not specified” was established.   This designation is assigned to 
substances that have a very low toxicity and, on t he basis of available data and the total dietary 
intake, do not pose a health hazard.  
 
Notification – Summary of Comments  
 
In response to Health Canada’s Information and Consultation Document on Health Canada's 
Proposal to Enable the use of the Food Additive 'Hexose Oxidase' in pizza mozzarella cheese, 
part-skim pizza mozzarella cheese, ultra -heat treated milk, and dough for bread, baking and 
pasta , published in November 2012, only one comment was received, in which no objection to 
the proposal was ex pressed , and no  new scientific information was submitted.  
  
Implementation and Enforcement  
 
The above modification came into force June 4, 2013 , the day it was published in the List of 
Permitted Food Enzymes . 
 
The Canadian Food Inspection Agency is responsible for the enforcement of the Food and Drugs 
Act and its associated regulations with respect to foo ds.  
 
Contact Information  
 
Health Canada's Food Directorate is committed to reviewing any new scientific information on 
the safety in use of any food additive, including hexose oxidase. Anyone wishing to submit new 
scientific information on the use of this  additive or to submit any inquiries may do so in writing, 
by regular mail or electronically. If you wish to contact the Food Directorate electronically, 
please use the words " hexose oxidase " in the subject line of your e -mail.  
 
   Bureau of Chemical Safety  
   251 Sir Frederick Banting Driveway  
   Tunney’s Pasture, PL: 2202C  
   Ottawa, Ontario K1A 0L2  
   E-mail: bcs-bipc@hc -sc.gc.ca