Now my questions:
- In your opinion, is it necessary to have an environmental monitoring program? There arent too many cases where I whould say that a EMP program in not necessary. In your case I would have one.
If so, what microorganisms would you look for as pathogens (Salmonella) or indicators? I chose to look for indicator microorganisms (e.coli, aerobic plate counts, enterobacteriaceae, for zones 1,2,3,4);
Salmonella makes sense to me
E. coli makes sense to me.
enterobacteracea makes sense. E.coli is an entobacteracea so, doing both might not make sense.
aerobic plate count makes some sense. IMO opinion they are usefull after sanitation to validate cleaning. They are usefull to show how "dirty" equipment becomes over time to justify cleaning schedules, etc. Not super usefull to determine a pass/fail situation for food safety as the limits are pretty arbitratry.
- Would you perform swabbing during production (as for pathogens) or before the start of the shift?
Ideally both. If before production is after a sanitation, it gives you indication that sanitation was effective. Performing them during production gives you information on what is happening during the production process.
To be honest, I cant quite figureout what your products and processes are - what risks you control, whats rte and whats not, what a sterilized product is, etc. However, in general 0.65 will prevent the GROWTH of pathogenic bacteria. It is not reliably bacterialcidal. IMO
More importantly and widely misunderstood - time temperature charts are for specific products. Especially when you DRY products, all of the standard time temperature charts go out the window. (and well above listeria target 70°C for 2 min)as you stated. As you remove moisture, organims like salmonella become more heat resistant. You most likely need to validate your thermal process.
Salmonella spp. are bacteria that ordinarily are sensitive to heat and high acidity. This sensitivity is often the basis for food processing used to control the presence of the organism. For example, it takes only 3 seconds to achieve a 5-log reduction in Salmonella at 71 °C (equivalent to 160 °F) in fruit juices (Ref. 4).
While considered heat sensitive, Salmonella spp. can become heat resistant in dry food products such as powdered milk or in low water activity products like chocolate syrup and peanut butter (Refs. 5 and 6). The relationship of Salmonella heat resistance to water activity has been well-studied at water activities between 0.99 and 0.85. Generally, Salmonella becomes more heat resistant as the water activity of a food becomes lower (Refs. 7 and 8). For example, it takes less than 5 minutes to achieve a 5-log reduction of Salmonella at 140 °F in a food with a water activity of 0.99 (Ref. 9). However, it takes 50 minutes to achieve the same reduction of Salmonella at 140 °F in a food with a water activity of 0.85 (Ref. 10).
The influence of the food on the heat resistance of Salmonella is not limited to the effects of water activity. The composition of the food (such as fat content, protein content, and acidity) may also affect heat resistance. For example, it can take more than 6 hours to obtain a 5-log reduction of Salmonella in milk chocolate at a temperature of 194 °F and more than 30 hours to achieve the same log reduction at 160 °F (Ref. 5).