Tuesday, August 10, 2010

Hazard Analysis and Assignment of Risk Categories

Overview
Hazard analysis consists of a system evaluation of a specific food and its raw materials or ingredients to determine the risk from biological (primarily infectious or toxin producing food borne illness microorganism), chemical, and physical hazards. The hazard analysis is a step procedure: hazard analysis and assignment of risk categories.

The first step is to rank the food and its raw materials or ingredients according to six hazard characteristics (A-F). A food is scored by using a plus if the food has the characteristic, and a zero (0), if it does not exhibit the characteristic. The six characteristics ranking system is applied for microbiological, chemical and physical hazard ranking, although the characteristics are somewhat different for microbiological and chemical/physical hazard as described later.

The second step is to assign risk categories (VI) to the food and its raw materials and ingredients based on the results of ranking by hazard characteristics. In addition, note that whenever there is a plus for hazard characteristics A (special class that applies to food designated for high risk population), the resulting hazard categories is always VI, even though other hazard characteristics B-F may or may not be a plus.

Several preliminary steps are needed before conducting the hazard analysis. These include developing a working description of the product, listing the raw materials and ingredients required for producing the product, and preparation of a diagram of the complete food production sequence. The listing of raw materials and ingredients is the starting point for the hazard analysis. If the specific mode of preservation for an ingredient is not known (raw, frozen, canned, etc), the ingredient may be assessed for each type of preservation technique that may be utilized in preserving the ingredient.


Microbiological Hazard Characteristics Ranking
Several minor changes in hazard F, to differentiate ranking for consumer products and raw materials and ingredients as received by the processor before any manufacturing steps. As indicated earlier, rank the product and its raw materials and ingredients exhibit the characteristic and a zero when they do not.

A sensitive ingredient is defined as any ingredient historically associated with a known microbiological hazard. The term ingredient normally also applies to raw materials. Sensitive ingredient was coined for microbiological hazards (infectious agents and their toxins) but it is also now used for ingredients and raw materials that are historically associated with known chemical or physical hazards.

The original list of microbiologically sensitive foods was based on the potential presence of the Salmonella species. Now any type of hazardous microorganism may cause a food to be sensitive, and the list of sensitive foods has grown, particularly with the recognition that Listeria monocytogenes is a known threat in many foods. If there is a question as to whether foods sensitive, it should considered sensitive until more information is available for purposes of clarifying its status.

Compounded ingredients may be considered sensitive if they are combinations of sensitive and non-sensitive ingredients. For example, a fat coated on milk powder, or compounded cheese flavor coated on starch. It is best to list all components of a blended materials to determine if the blend contains a sensitive ingredient and also determine if it has received a controlled processing step that destroy hazardous microorganisms. In some cases, it is important to determine if microbiological toxins may also be present in a processed food if it is to be used as an ingredients (e.g. heat stable staphylococcus enterotoxin in canned mushroom).

Many raw materials and ingredients are not considered microbiologically sensitive even though they may occasionally be contaminated with hazardous microorganism.

Chemical and Physical Hazard Risk Assessment Procedures

Hazard characteristics for chemical and physical agents were developed in 1990 for use in the ESCA genetics Corporation training course, “A Practical Application of HACCP,” and were recently published. They are designed so that both chemical and physical hazards in food may be assessed by using the same six hazard characteristics.
Generally, hazard analysis for chemical and physical hazard is conducted like the procedure for microbiological hazards provided in the NACMCF guide. Although the six hazard characteristics are somewhat different, the same plus (+) and zero (0) scoring system and hazard assignment procedure are used.