Handbook of Meat Processing

130 Chapter 6

Heating of an Emulsion Type Sausage

Batter (with Fat)

The addition of salt and water at low tem-

peratures (0 – 10 ° C) causes a denaturation in

myofi bers by swelling and dissolving, as

described earlier. If the meat is heated, the

shrinkage is prevented, as shown in the

experiments given in Table 6.2.

The proteins in the myofi bers at physio-

logical conditions (about 0.1 M salt, pH 7,

and 37 – 38 ° C) are insoluble. They are kept

together by chemical bonds like S – S bridges

or (reduced) Schiff bases (such as those in

collagen), by ionic attraction (Van - der - Waal

forces), hydrogen bonds, or hydrophobic

interactions of the lipid side chains of the

amino acids. On denaturation with salt

and heat, the native structure changes differ-

ently, as shown in Figure 6.7. The heat

enhances the hydrophobic bonds of protein

side chains, and the proteins become insolu-

ble or shrink. With salt, the denaturation

leads to a different structure, where the

hydrophobicity is also enhanced (Fig. 6.7 ,

right side), due to the weakening of ionic

attraction and loss of hydrogen bonds.

The swollen myofi brillar protein structure

becomes wider, and the hydrophobic side

chains are at the surface.

41% from the reference value of 28%. But
if 2% salt is added to the meat plus water
(D) (Table 6.2 E), then the cooking loss is
low again, at 8%, near to what it would be
without water addition (C). The addition of
water and fat (F) shows a cooking loss of
33%. In experiment G, 2% salt is added to
the composition of F, and the cooking loss
is the lowest of all experiments shown in
Table 6.2.
If one relates the cooking loss to the total
content of water/fat in the product, then a
meat piece (reference) loses 37.5% of total
water; mincing (B) with the addition of 50%
water (D) or 25% water and 25% back fat
releases about 32/33% of the total water in
the product. The addition of 2% salt with or
without added water reduces the cooking loss
to 6.5/8% from 32/33% without salt; salt,
water, and fat (experiment G) reduces it
further to 2% of total water loss. The fat
cookout is also reduced by salt.
In conclusion: mincing (comminuting)
enhances the water - binding slightly; addition
of salt reduces the cookout considerably even
if water is added. The comminuting of addi-
tional fat and salt strongly improves the
water - and fat - binding. The latter happens in
emulsion type sausages, where salt and/or fat
are needed for a sausage without cookout.

Table 6.2. Infl uence of the addition of salt, water, fat on cookout in meat and comminuted meat
( B to G )

Heating was carried out from about 7 ° C with about 2.5 ° C/min until 80 ° C was reached. The size of meat in A

was 3 cubes of 10 g each, from B - G, 30 g of mince or batter; lean pork contains 75% water

Code Composition % water loss

at 80 ° C a

water loss of

total water % b

% fat loss

at 80 ° C a

fat loss of

total fat b

A

reference

piece of lean pork

( < 2% fat)

28 37.5 0 —

B minced lean pork

( < 2% fat)

24 32 0 —

C B + 2% salt 6 8 0 —

D B + 50% water 41 33 0 —

E D + 2% salt 8 6.5 0 —

F B + 25% water + 25%

back fat

33 33 10 37

G F + 2% salt 2 2 1 4

a % related to the material weight
b % related to total water/fat weight in the meat or mixture