The Case Against Raw Frozen Pet Foods
presents few problems, however, any residual ATP present in the tissue during freezing will contract the muscle upon thawing resulting in a more unpalatable product. Mixed RF foods would hide this problem.
6. Free Radical Problems Masked – Essential fatty acids and other health enhancing lipids are critical in the diet. Once foods are ground, mixed, exposed to air, light and pro-oxidants such as heme iron and other metals found in plant and animal tissue, the contained lipids are oxidized to chain reaction producing free-radicals, causing rancidity and oxidant toxins. Freezing at appropriately low temperatures slows this process but does not stop it. The temperature in conventional freezers used for RF foods is not insurance against such oxidation. Because the frozen state masks olfactory detection of rancidity, foods that would be otherwise rejected end up being consumed. The free-radical pathology potential can then work its chronic degenerative disease and immune weakening effects.
7. Freezer Burn Indicates A More Serious Problem – Air reaching the meat surface is the cause for the freezer burns that result in the typical grayish-brown leathery spots. Frozen water on the surface or just beneath it sublimates (from solid state directly to vapor) into the air, causing moisture to be lost from the meat over time resulting in discoloration and a dry, leathery texture. Proper packaging helps maintain quality and prevent freezer burn, however most packaging is permeable to air. The prevalence of freezer burn in RF products speaks to the fact that the product is being oxidized and with that creating free radical toxins to lay the seeds for various degenerative diseases.
8. Display Packaging Causes Free Radicals – Light, as well as air, can promote free radical production. Retail display packaging that is clear or light permeable permits light to catalyze the free radical (disease promoting) process.
9. Frozen Products Are Not Inert To Degradation – In frozen storage there is deterioration in organoleptic quality – meat texture, fat turning granular and crumbly, and discoloration. Microbial enzymes also remain active, especially lipases that break down fats increasing their susceptibility to oxidation.
10. Frozen Foods Can Lead To Acidemia – Tissue degradation and oxidation under high heat freezing (above 29° F), which occurs along the supply chain with most RF products, also leads to acidification. Increasing acid consumption can contribute to acidemia that lies at the base of virtually every chronic degenerative disease plaguing modern pets. (See reference below.)
11. Temperature And Time Are Critical – Ice nucleation, as opposed to ice crystallization, is the primary vector in producing a stable, tasty, frozen product. Freezing is a technically complex process based on the optimum combination of temperature and time, amongst other factors. In the wrong processor’s hands, slips in proper freezing care can lead to a microbiologically unstable product and/or a sensory inferior one. Rapid freezing leads to nucleation, thereby preventing undesirable large ice crystals from forming throughout the product. With rapid freezing the molecules don’t have time to form positions in the characteristic six-sided snowflake, so nucleation overrides crystallization. On the other hand, slow freezing (the usual RF situation) creates large ice crystals, which on thawing causes cellular damage to the meat. This in turn causes meat to “drip” – lose juiciness – and form a perfect liquid medium for bacterial growth.
12. The High Risk In Thawing – Thawing is another critical phase in the freezing process as it involves a change from crystal ice to melted water, which upon reabsorption results in microbial reactivation. Pathogenic bacteria inherently contaminate raw meat, fish, and poultry and will begin to multiply again when the temperature reaches just 29.3º F – which is below freezing! Thus a product that may appear subjectively frozen could be a veritable incubator of pathogens. When consumers attempt to thaw RF foods, dangers dramatically increase. The surface temperature rises long before the interior is sufficiently thawed to serve. For example, it takes about 15 hours for the middle of a 22-pound turkey to get to 32º F. In the interim the surface temperature rises to 53º F. In this amount of time there would be about 4 multiplications
of spoilage bacteria as well as non-detectable multiplications of pathogens. The FDA Model Food Code (1999) recommends that food be thawed in the refrigerator or in flowing water. Thawing RF food in the refrigerator can be inefficient and time consuming, in addition to occupying refrigeration space required for other food items. Most of all, this lengthy procedure can lead to the risk of cross-contamination when the drip from