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FoodCap Science - FAQ

FoodCap Primal Handling

The benefits of the FoodCap Primal Handling are predicted largely on the basis of the generally accepted principles that define meat product quality, together with proprietary knowledge about the effects of the capsule on product attributes. The confidence that the FoodPac system will exceed the minimum performance requirements are based on the contribution of three key processing controls: 

  1. Improved temperature control to reduce microbial load and enhance shelf life.
  2. Use of modified atmospheres will reduce microbial load, enhance appearance and enhance shelf life.
  3. The mechanical pressure used in the boneless meat system to improve water binding, improving product appearance and eating quality.

 Any one of these process controls can be expected to produce a measurable benefit; the three together offers a substantial margin of safety.

Micro Performance

The actual microbiological status of any piece of meat passing through the system will depend on its initial microflora and subsequent contamination during further processing and handling.

Creation of an anoxic environment within the FoodPac Capsule prevents the growth of the high spoilage potential strictly aerobic Pseudomonas spp and effects an ecological shift that allows a low spoilage potential lactic acid bacteria dominated microflora to develop.

Furthermore, because fermentative metabolism is less efficient in respect to energy production, the development of the low spoilage potential lactic microflora is considerably slower than that of its high spoilage potential aerobic counterpart. An additional microbiological bonus is provided by anaerobiosis; the high spoilage potential facultative micro-organisms such as Brochothrix thermosphacta, Shewanella putrefaciens and psychrotrophic members of the family Enterobacteriaceae are unable to grow on meat of pH less than 5.8.

Product Shelf Life

The shelf life of fresh meat products is defined primarily by meat colour: during retail display, the red oxymyoglobin that is responsible for the desired fresh meat colour converts to the brown metmyoglobin. Generally recognised strategies to maintain colour stability and, hence, shelf life of meat products are:

  • Exclusion of oxygen during storage
  • Effective temperature control
  • Use of a modified atmosphere 

Strict exclusion of oxygen during storage maintains the native antioxidant capacity.
All body tissues have antioxidant systems that are essential to maintaining their normal function. Many of these survive in meat, and contribute to preventing the browning reaction of myoglobin. However, since they are not replenished in meat as they would be in living systems, there is a finite amount of antioxidant available in a meat product, and their rate of usage depends on the degree of exposure to oxygen.

The material used in the manufacture of the FoodCap capsule is effectively impervious to oxygen, if only because of its far greater thickness compared with barrier bags. Furthermore, the surface area to volume ration is much larger for the capsule compared to an individually wrapped primal. The net effect is that there is no depletion of antioxidant during storage in the capsule.

Reference MIRINZ 2002 (C. Daly)

Product Appearance

The appearance of fresh meat products is largely defined by meat colour, and the use of the low temperature/high oxygen treatment will ensure a high level of oxygenation of the surface myoglobin layers and, hence, a vibrant red colour.
 
A second major determinant of product appearance is the influence of the water binding capacity of meat. High water binding capacity gives meat a fresh, hydrated appearance, and retards the loss of fluid from the meat during display in the retail pack. The drip that accumulates in the retail pack is not only unattractive in itself, but its loss can give the meat a wilted appearance.
 
The FoodCap primal compression system increases the water binding capacity of meat.
There are no generally recognised techniques to control water binding capacity in meat. The normal procedure is to disguise the drip by the use of soaker pads to absorb the exudates.
 
In contrast, a well-documented benefit of the FoodCap primal compression system is the ability to increase water binding capacity in meat. The benefit arises from the use of mechanical pressure to compress the meat during storage. In the period immediately after death, the protein structures in muscle contract and expel fluid from inside the cell into the intercellular spaces. This water is then able to migrate to a cut surface and escape to form drip. The use of mechanical pressure in the capsule immobilises the unbound fluid, which then can become reincorporated into the cells of the meat when the protein structures breakdown during the tenderising process. The fluid fraction, once reincorporated, is firmly bound and does not accumulate in retail packs as drip.
 
A demonstrated benefit of using the system is to produce well hydrated meat with very minimal tendency to drip during retail display.
 
The increased water binding capacity of meat processed by the system will have benefits for eating quality. During cooking, meat can lose up to 30% as fluid losses. By increasing water binding capacity, these losses are reduced, and eating quality enhanced through improved juiciness and reduced perception of toughness.

Reference MIRINZ 2002 (CC. Daly)

Modified Atmosphere

The FoodCap uses modified atmospheres to control microbial growth.

A procedure used to manage microbial growth in food products is the use of modified atmospheres. The most important of these is high carbon dioxide (CO2) atmospheres, which, at concentrations greater than 15%, is capable of either killing microorganisms, or substantially reducing their ability to multiply.
 
There is also evidence that the use of high oxygen environments can reduce viable microbial numbers when the exposure follows soon after a prolonged period in anaerobic conditions. Because the vacuum pack environment has very low oxygen levels (some diffusion of oxygen may take place through the barrier bag) or completely oxygen free in the case of the FoodCap capsule, the microorganisms adapt to this environment and a sudden exposure to high oxygen conditions becomes toxic.

Reference MIRINZ 2002 (CC. Daly)

Mechanical Compression of Boneless Meat

Mechanical pressure is applied to the meat after the FoodCap capsule has been packed in the boning room. This pressure serves to remove residual air pockets and void space between the meat cuts inside the capsule.

Although loaded capsules (containing boneless meat) are evacuated (using FoodCap’s unique deep space vacuum process) and then gas flushed after sealing, they should not be considered to be carbon dioxide packaging systems as only the head space above the bulk of meat is gassed. The combination of mechanical compression and deep vacuum/gassing flushing the head space together create the anaerobic environment necessary to allow prolonged storage.

In the case of the bone-in meat storage, the meat primals or portions are packing in the capsule without the use of the compression system. The capsule is sealed after packing and undergoes FoodCaps deep space vacuum – gas flush process. Capsules can be flushed with a range of gas formulations and rations depending on the customers specific storage requirements.

Product Yield Loss (purge)

The mechanical pressure used in the FoodPac capsules (boneless meat) forces the meat cuts together and maintains a compressive force against all the cut surfaces of the meat. This has the effect of countering capillary action that draws loosely bound fluid within the meat to the surface, where the fluid is lost from the cut as purge. These capillary forces are prevalent in the interface between meat and vacuum pack barrier bags, and contribute to increasing purge loss during storage and ageing.

Compression of the meat between the internal pressure plates effectively creates a single “block of meat”. Consequently, the bulk of the meat, although not exposed to the antimicrobial influence of carbon dioxide, is however very effectively maintained in a highly anoxic condition.
 
In addition to reducing purge, immobilising the loosely bound fluid in the meat during the ageing period allows the fluid to be reabsorbed into the cellular structure. During the period immediately after slaughter and before rigor mortis sets in, muscle undergoes a contraction that generate pressures inside the muscle cells; these pressures contribute to squeezing fluid from inside the cell and into spaces between the cells. Once outside the cell, the fluid is in a loosely bound state and is easily lost as purge. As the ageing process progresses, the muscle structure breaks down (this is the process responsible for tenderisation) and the ‘squeeze’ within the cells relaxes; so that fluid can then be reabsorbed into the cell if it hasn’t migrated to the outside as purge.

This reabsorption means that meat cuts become more firm (turgid) in the raw state, less prone to losing fluid during retail display and less loss of fluid during the cooking.

Reference Carne Technologies 2002 (CC Daly)
Reference MIRINZ CR578 (RG Bell, CC Daly)
Reference MIRINZ CR429 (N. Penney, S.J. Mott, R.G. Bell)

Food Safety

The meat packed in FoodCap capsules is typically handled fewer times from the point of boning/packing to the point of further processing. The system does not require meat to be removed from vacuum bags for either slicing or sawing before being packed onto consumer trays.

There is increasing concern that the psychrotrophic pathogens Aeromonas hydrophila, Clostridium botulinum, Listeria monocytogenese and Yersinia enterocolitica could grow on meat during prolonged chilled storage. If the packaging system allowed such pathogen growth but inhibited the growth of spoilage micro-organisms, thereby removing any organoleptic warning that excessive microbial growth had occurred, consumers might ingest high numbers of pathogens on the apparently wholesome meat.

With raw meats cooked before consumption, the hazard to health so posed would probably be minimal except where pathogen growth was accompanied by toxin formation (Clostridium botulinum). However, this would not be the case where meats are consumed raw, eg. steak tartare, or if the meats cross contaminate other foods that are not cooked before consumption.

The conditions within a FoodCap capsule are not expected to eliminate either the cold tolerant or mesophilic pathogens that must be assumed, on occasion, to be present on raw meat. No amount of carcass inspection or process hygiene can assure the absence of pathogens from raw meat. However, their proliferation can be effectively prevented by adequate refrigeration. Therefore, the use of FoodCap capsules for ageing and storing meat is unlikely to potentiate a health hazard above the acceptable level currently associated with conventional vacuum packaging.

Reference MIRINZ 2002 (C. Daly)

Multi Species Storage

The use of the FoodCap Capsule for the chilled storage of beef, pork, venison, and lamb is hygienically acceptable and with the absence of off odour’s and the reduction in weight and quality loss associated with drip release offers potential advantages for the reliable storage and transportation of chilled meat.

Reference MIRINZ CR429 (N. Penney, S.J. Mott, R.G. Bell)

An essential requirement for any novel meat storage system is to demonstrate that it can at least match or surpass existing systems in terms of product storage life, food safety and product quality.

To this end, Carne Technologies has undertaker an extensive comparison between the FoodCap Primal 2 MAP system and a conventional vacuum packing storage system: this comparison considers a range of species; including beef, pork, poultry (chicken) and lamb, a range of primal cuts within each species, and a range of storage times for each of the primals (up to 63 days in beef and lamb, 35 days in pork, 21 days in beef and pork trim and 16 days in poultry).

After storage, the assessment evaluated microbiological status of the product, the magnitude of purge losses during storage, effects on retail display life and on the tenderness of the product.

The FoodCap Primal 2 system (modified atmosphere system) can be used for both bone-in and boneless product and places the primals on a shelving system inside the capsule. Atmospheric oxygen is removed via FoodCaps deep vacuum process and replaced with a modified atmosphere. Evaluations were undertaken on the Primal 2 system, based primarily on a 50% CO2 / 50% N2 gas mix.

The control of microbial growth during storage was assessed by measurements of aerobic plate counts (APCs) to provide a non-specific count of organisms, and of Entrobacteriaceae (EBCs) to provide a more specific measure of a class of spoilage organisms. None of the time-points reached the point of overt spoilage with either the FoodCap capsule or VP systems. However, generally the FoodCap Primal 2 system consistently resulted in lower APCs and EBC’s in all species and cuts than the VP across all periods of storage.

Reference Carne technologies (Dr N Simmons 2015)

Product Confinement Odour

Confinement odour is a rather loosely used term applied to unpleasant odour’s evident on opening vacuum-packs.
 
Characteristically, such odours dissipate when the meat is exposed to the air for a few minutes. True confinement odour, as opposed to packaging material taints, is indicative of incipient spoilage and generally becomes evident during the final quarter of a product’s storage life.
 
The absence of confinement odour even after prolonged storage in a FoodCap capsule can probably be attributed to the virtual exclusion of high spoilage potential facultative anaerobes from the microflora developing in the bulk of the meat. Furthermore, growth of these microorganisms on exposed surfaces would be prevented by the elevated concentration of carbon dioxide in the FoodCap atmosphere. This phenomenon also accounts for the characteristic absence of confinement odours in true carbon dioxide packs.
 
Meat stored in capsules can be expected to be unaffected by confinement odours provided strict attention is paid to temperature control and storage periods are not excessive.

Product temperature control

The principle determinant of growth rate of microorganisms on food products is environmental temperature, and the number of organisms present can be predicted from the initial level of contamination and the cumulative temperature history of the product. Therefore, the time/temperature history of a product will provide a good indication of the extent of microbial contamination.

The specified final temperature used in the FoodCap system, at -0.5°c to - 1.5°c, is as low as is possible without freezing the product. The benefits of this low temperature has been amply demonstrated in the chilled export of meat product, but is rarely attempted for the storage of product for the local market.

The FoodCap temperature control from the centralized cutting plant to the retail shelf is then maintained by the use of sealed capsules, where the capsules large size creates a thermal inertia that minimizes temperature fluctuations associated with transfers during transport.

 Reference MIRINZ 2002 (C. Daly)

Disclaimer

Fresh chilled meat processing and distribution is a highly complex area with no two supply chains or processing environments being exactly the same.
Many different practices, methods and technologies are used by meat processors during the multiple handling and preparation stages starting at the point of slaughter, then along the supply chain through to final processing, packing, and distribution.

The material in this website is provided as an overview of the FoodCap technologies and the potential outcomes that can be achieved, based on meat trials and operational experience gained using the systems in New Zealand.

Every effort has been made to ensure the accuracy of this information. However, because research and development can involve extrapolation and interpretation of uncertain data, FoodCap and research organisations involved in meat trials on behalf of FoodCap (MIRINZ, Ag Research, Carne Technologies) will not be responsible for any error or omission in the data presented. To the extent permissible by law, neither FoodCap or the research organisations named above nor any person involved in the generation of this information accepts any liability for any loss or damage whatsoever that may directly or indirectly result from any advice, opinion, representation, statement or omission, whether negligent or otherwise, contained in the information presented in this website.