Processors Should Ponder Using Mechanical Action for Boneless Meat
Mechanical action should be considered when manufacturing any boneless meat item.
Tumbling, blending or massaging accelerates cure, salt and phosphate distribution; thus, improving product bind and color.
Massaging serves to equilibrate ham color uniformity better than other systems. Massaging should be considered over other forms of mechanical action when improved color uniformity is expected and when muscles of varying myoglobin concentrations are combined to form a product.
This is particularly important when knuckles are utilized in conjunction with other ham muscle groups. Severe disruption of muscle pieces and myoglobin migration are provided by the prolonged massaging durations allowing equilibration of myoglobin concentration among the various muscle groups.
Tumbling provides mechanical energy to the food system when muscle integrity must be maintained. Tumbling imparts primarily collision energy providing excellent cure distribution and muscle softening; some frictional energy is employed by this process, as well.
Vacuumization during tumbling is required to avoid foaming of extracted proteins.
Foam formed during tumbling without use of a strong vacuum is largely denatured salt soluble proteins. This denaturation reduces the functionality of the protein glue that serves as glue for holding muscle groups together.
The protein foam detracts from the final product appearance as small bubbles or pinholes form throughout the musculature of the cooked ham and in larger voids located between muscle pieces.
Massaging is the application of frictional energy. Distribution of cure solutions and resultant salt soluble protein extraction is slower for massaging than for tumbling; consequently, recommended durations for massaging are longer for massaging than for tumbling or blending.
Generally, four hours of continuous tumbling are equivalent to 12 hours of intermittent massaging or eight hours of continuous massaging.
Since meat tearing and muscle structural loss occurs during massaging, massaging should not be considered where products having relatively intact muscle structure and some form of muscle orientation are required product characteristics.
Blending should employ vacuumization. Moreover, blending requires short extraction times as a result of the severe muscle tearing produced by blending; blending duration is rarely longer than 30 minutes.
Blending, tumbling and massaging characteristics are summarized in the following table:
Duration Capacity Muscle
(hrs.) (lbs.) Tearing
Massaging 8-12 1,100 Severe
Tumbling 4 15,000 Slight
Blending .5 15,000 Very Severe
Several commercial systems employ combinations of tumbling and massaging; and usually tumbling guidelines are utilized for meat conditioning employing combination systems.
Product temperature control
Product temperature control during addition of mechanical energy is very important. Two programs regarding temperature regulation during tumbling or massaging have evolved. Many phosphates precipitate from solution (regardless of whether the phosphate is in the brine solution or within the meat itself).
The lowest safe temperature for brine injection and ham conditioning was long considered to be 37 degrees F. and 40 degrees F. Phosphates soluble in ice water, and that remain soluble in brines at temperatures as low as 18 degrees F, allow ham tumbling and massaging at temperatures as low as 26 degrees F to 28 degrees F.
Claims exist that salt soluble protein extraction is improved using lower temperatures.
Use of lower temperatures for blending possibly allows less of the protein extracted to become denatured via meat enzymes, salt and temperature.
However, it is important to note extensive research has demonstrated that optimal protein extraction occurs at temperatures near 45 degrees F.
Whether cold or warm temperatures are maintained during curing, the form utilized for the addition of mechanical activity remains a matter of preference, as well as a matter of what works and doesn't work in a given situation.
This should be kept in mind for new product development and when considering new technology.