Revised IFU Method No. 12 for Alicyclobacillus spp. Testing in Fruit Juices

Alicyclobacillus spp. can be difficult to control in fruit juice products as their spores survive juice pasteurization temperatures and may subsequently germinate and grow after processing if conditions are suitable. The economic impact of such incidents can be very high. The International Fruit and Vegetable Juice Association (IFU) published a revised Method No. 12 standard for detection and enumeration of spore-forming, thermo-acidophilic bacteria (Alicyclobacillus spp.) in 2019.

• juice and juice-related products and their ingredients intended for human consumption
• environmental samples including process water in the area of juice, juice-related production, and handling
• other beverages not containing juices and their ingredients including syrups

This third edition from 2019 cancels and replaces the second edition of IFU Method No. 12: 2007, which has been technically revised. The main changes introduced in the third version, compared to IFU Method No. 12:2007, are considered as major. The IFU method no. 12 is now more precise, more structured, and therefore more reproducible. It includes improved culture media formulations and performance criteria which are in agreement with ISO procedures.

Changes to IFU Method No. 12

An ISO-compliant validation within the IFU Microbiological Working Group was performed, ensuring a user-friendly laboratory implementation. The main changes, compared to IFU method no. 12:2007, will be the following

• the title of the method has been changed to “Method on the Detection and Enumeration of Spore-forming Thermo-Acidophilic Spoilage bacteria (Alicyclobacillus spp.)”,
• the optional usage of several media has been changed to the usage of one liquid (BAT broth) and one solid medium (BAT agar),
• a new pour plating method is introduced for enumeration in 1 g sample,
• performance testing for the quality assurance of the culture media has been added,
• the determined performance characteristics for this method have been added as a summery,
• optional pre-incubation of packed ready-to-drink products has been added to Annex E,
• matrix-dependent special processes have been added to Annex F.

11-minute talk: The new IFU Method No. 12:2019

Dr. Andreas Bubert explains the Alicyclobacillus spp. test procedure according to the new IFU Method No. 12:2019.

Procedure A:
Direct Enumeration by Pour Plate Technique acc. New IFU Method No. 12:2019

Procedure B:
Direct Enumeration by Filtration Technique acc. IFU Method No. 12:2019

Procedure C:
Detection of Alicyclobacillus spp. by Enrichment acc. New IFU Method No. 12:2019

As a worldwide leading provider of a broad range of granulated and ready-to-use culture media for food, beverage and water microbiology, we closely track and support the development of relevant standards aimed at increasing consumer confidence and safety.

Our GranuCult^® granulated media, Readybag^® pre-weighed granulated media in ready-to-use bags, ReadyPlate™ and ReadyTube^® ready-to-use media are all compliant with EN ISO 11133:2014. All information regarding compliance with additional reference standards are displayed on the product label and in the product’s technical information available on our website.

Figure 1. GranuCult^® Prime BAT Agar and BAT Broth

Figure 2. Alicyclobacillus spp. on BAT Agar