Factors influencing the particle size distribution of flaked meat. I. Effect of temperature, aperture size and prebreaking before flaking

Abstract

Steer chuck and blade were pre-broken by grinding at --3.0°C and -7.0"C, re-tempered to -3.O"C and -7.0°C, respectively, and then flaked through aperture sizes of 6.1 mm, 9.9 mm or 19.0 mm. Meat was also flaked at -34°C without being pre-broken.More ice melted at the lower temperature; the gain in enthalpy was also higher at -7°C than at -3°C. Size measurements, made using video image analysis, showed that particles produced at the lower temperature had a smaller mean diameter and a greater surface area. Of the three factors investigated, temperature was the most important influence on particle thickness. For a given feed material there was a good correlation between mean diameter and aperture size.High speed photography results showed that pre-broken meat tended to break-up more readily on the impeller than intact pieces, resulting in pieces of smaller mean diameter.

Effect of temperature on the particle size distribution of flake‐cut meat

“…This is to be expected because the specific heat of meat at -2°C is about seven times that at -7°C (Miles et al, 1983) and, thus, a given heat input would result in a greater rise in product temperature at -7°C than at -2°C. That significantly more ice melted at -7°C (P<0.05) is in agreement with previous results (Ellery, 1985;Sheard et al, 1989Sheard et al, ,1990b and suggests that more heat is gained at the colder temperatures, probably because of greater frictional heating (Sheard et al, 1990b). There was a significant effect of temperature at flaking on the number of particles per gram of sample, projected surface area per gram and mean thickness of particles (P<O.OOl) (Fig.…”

“…Previous results from this laboratory have shown that particle size depends upon the temperature at which meat is comminuted (Ellery, 1985;Sheard et al, 1989Sheard et al, , 1990b. Two to three times more particles are produced at -7°C than at -3°C (Sheard et al, 1989(Sheard et al, ,1990b and, as this has been shown to be true for at least two different methods of comminution (meat pre-broken by grinding, and flake-cut meat), the effect has been attributed to the temperature-dependent mechanical properies of the raw material (Sheard et al, 1989).…”

“…Two to three times more particles are produced at -7°C than at -3°C (Sheard et al, 1989(Sheard et al, ,1990b and, as this has been shown to be true for at least two different methods of comminution (meat pre-broken by grinding, and flake-cut meat), the effect has been attributed to the temperature-dependent mechanical properies of the raw material (Sheard et al, 1989).…”

Factors influencing the particle size distribution of flaked meat. II. Effect of aperture size, number of cutting stations, rotational speed and impeller design

“…In the light of this, and previous work (Sheard et al, 1990b), we are able to comment on the relative importance of some of the large number of factors that potentially could influence the size distribution of flaked meat. Seven factors have been examined: aperture size, number of cutting stations, rotational speed, impeller design, temperature of the meat, whether or not it has been pre-broken, and input piece size.…”

“…Diced meat flaked through an aperture size of 6.1 mm, for example, resulted in more particles than bandsawn meat flaked through the same aperture size, with the same number of cutting stations (72 compared with 38 particlesg-I), but less particles than meat which was pre-broken and then flaked (164 particlesg-l) (see Table 3 in this paper and Table 5 in Sheard et al, 1990b). These three treatments also differed in their size distributions, with the diced material having a greater proportion of large particles than the pre-broken material but less than the bandsawn material (Fig.…”