Food Biochemistry and Food Processing

28 Biochemistry of Fermented Meat 643

reduction of nitrite to nitric oxide is favored by the
presence of ascorbic and erythorbic acids or their
sodium salts. They also exert antioxidative action
and inhibit the formation of nitrosamines.
Carbohydrates like glucose and lactose are used
quite often as substrates for microbial growth and
development. Disaccharides, and especially poly-
saccharides, may delay the growth and pH drop rate
because they have to be hydrolyzed to monosaccha-
rides by microorganisms.
Sometimes, additional substances may be used
for specific purposes (Demeyer and Toldrá 2004).
This is the case of glucono-delta-lactone, added at
0.5%, which may simulate bacterial acidulation. In
the presence of water, glucono-delta-lactone is
hydrolyzed to gluconic acid and produces a rapid
decrease in pH. The quality is rather poor because
the rapid pH drop drastically reduces the activity of
flavor-related enzymes such as exopeptidases and
lipases. Phosphates may be added to improve stabil-
ity against oxidation; vegetable proteins, such as soy
isolates, to replace meat proteins; and manganese
sulphate as a cofactor for lactic acid bacteria.

Spices, either in natural form or as extracts, are

added to give a characteristic aroma or color to the

fermented sausage. There are a wide variety of

spices (pepper, paprika, oregano, rosemary, garlic,

onion, etc.), each one giving a particular aroma to

the product. Some spices also contain powerful

antioxidants. The most important aromatic volatile

compounds may vary depending on the geographi-

cal and/or plant origin. For instance, garlic, which

gives a pungent and penetrating smell, is typically

used in chorizo, and pepper is used in salchichón

and salami. Paprika gives a characteristic flavor

and color due to its high content of carotenoids

(Ordoñez et al. 1999). The presence of manganese in

some spices, like red pepper and mustard, is neces-

sary for the activity of several enzymes involved in

glycolysis and thus enhances the generation of lactic

acid (Lücke 1985).

STARTERS

Typical fermented products were initially based on

the development and growth of desirable indigenous

Table 28.2.Some Decisions to Adopt and Options to Choose in the Processing of Fermented

Meats

Aspects Options

Type of meat Pork, beef, etc.

Quality of meat Choose good quality. Reject defective meats (pork PSE and DFD), abnormal

colors, exudation, etc.

Origin of fat Choose either chilled or frozen (how long?) fats. Reject oxidized fats.

Type of fat Control of fatty acids profile (excess of PUFA?).

Ratio Choose desired meat:fat ratio.

Particle size Choose adequate plate (grinder) or speeds (cutter).

Additives: salt Decide concentration.

Additives: curing agent Nitrite or nitrate depending on type and length of process.

Additives: carbohydrates Type and concentration depending on type of process and required pH drop.

Spices Choose according to required specific flavor.

Microflora Natural or added as starter?

Starters Choose microorganisms depending on type of process and product.

Casing Material and diameter depending on type of product.

Fermentation Conditions depending on type of starter used and product.

Ripening/drying Conditions depending on type of product.

Smoking Optional application. Conditions depending on type of product and specific

flavor.

Color Depends on raw meat, nitrite, and processing conditions.

Texture Depends on meat:fat ratio, stuffing pressure, and extent of drying.

Flavor Choose adequate starter and process conditions.

Water activity Depends on drying conditions and length of process.