A) Ingredient database
(Need UNIFYING LANGUAGE to link and identify (implicit) quality drivers)
Key for internal and external knowledge management
B) (Parallel) Processing effects on Quality Indicators
C) Closed shelf-life: Product distribution and storage effects
D) Consumer use effects
Appendix: Quantitative Integrated Preservation Microbiology
Preservation Microbiology dimensions
1) The initial microbial contamination level and its history will be represented in dimensions which account for :
- The organism’s distribution in raw materials and ingredients.
- The organism’s state (e.g., process susceptibility, injury, acquired stress response, etc.).
2) The nature of the preservation process, e.g.,
- The heating intensity (pasteurization, sterilization)
- Alternative, non or reduced thermal preservation technologies and their parameters (e.g.: High Pressure Pasteurization(HPP), electron beam (EB), filtration)
3) The product’s characteristics, including formulation and storage, e.g.,
- Temperature, pH, water activity, organic acids, salt, chemical and biological preservatives (sorbic acid, nisin) and “cryptobials” (hidden antimicrobial factors).
- Microstructure, e.g., emulsion type, solid matrix’s strength.
4) Economic and social factors such as:
- Consumer use
- Logistic considerations, mass production, etc.
Traditional preservation process and product design can usually be treated as a relatively simple solution to an optimization process in a small number of dimensions. Examples are finding the optimal conditions of static retorting, acidification, drying, freezing, salting, etc. Process bottle-neck organisms are historically known (bacterial sporeformers, lactobacilli, (osmophilic) yeasts, etc.). This may result in compromising the products quality which could have been avoided had more dimensions been considered. Adding or change in dimensions may fundamentally alter the selection pressure in the preservation system and can create or amplify niches for (new) hazardous (e.g. prions) or spoilage process bottleneck microorganisms. The traditional target in low acid foods sterilization, Clostridium botulinum spores is not the most heat resistant microorganism. For UHT processes Bacillus sporothermodurans has emerged as a notable example.
Common rules, like the F0 = 3’ at 121°C requirement (based on a 12D reduction of C.botulinum spores and simplifications like the first order inactivation kinetics assumption (the D- and Z-value concept) have recently come under renewed criticism (e.g., Peleg & Cole, 1998, van Boekel 2002). There are potential situations where they may even pose a safety or spoilage risk.
The time seems to be ripe to consider and develop a new unified approach to food preservation, which will allow a more balanced evaluation of outstanding problems and a more realistic estimation of the associated safety and spoilage risks. The traditional “worst case scenario” or fail-safe approach may not be the best guide if delivering the full range of health and other benefits of foods is to be accomplished. This is particularly the case when mildly preserved products are concerned.
Alternative approaches like the current version of Microbiological Quantitative Risk Assessment may be insufficient because it only deals with direct safety hazards but not with the reduction or elimination of spoilage, which is key to making stable food products.