For the production of good quality pasta, you should:
– make a choice of product range depending on the quality of the processed flour;
- use flour with good pasta properties;
— observe the optimal modes of conducting all stages of the technological process;
- use additives-improvers in the processing of low-quality flour.
Pasta Defects Pasta defects can be caused by two main reasons. Firstly, defects caused by the quality of the processed flour, and secondly, caused by deviations from the optimal modes of carrying out individual stages of the technological process.
Raw pasta defects include:
- sticking of products together;
- rough surface;
- whitish mealy surface;
- stretching of pressed out long products under the action of its own weight;
— longitudinal rupture of pressed out tubular products;
- crumpled ends of tubular products;
- flattened tubes;
- cracks in the places of inflection of products on bastuns.
The most typical defects in finished products are:
- the color is whitish and white with a gray or brownish tint (with a reduced yellowness index);
- powdery fracture;
- whitish surface;
- rough surface;
- the presence of crumbs and deformed products;
- reduced indicators of cooking properties (increased stickiness and dry matter content in cooking water, a decrease in the shape retention index);
- soaking (souring);
Whiteness. In the absence of vacuumization of the dough on screw pasta presses, whitish pasta can be pressed out even when durum wheat flour is used. It has been established that the whitish color of pasta is due solely to the physical process of saturating the dough with many tiny air bubbles during its intensive grinding in the screw chamber, i.e. is a consequence of a kind of whipping dough in the screw chamber and obtaining a foamy structure. As a result, the color of the products becomes white even in the presence of a significant amount of carotenoid pigments. When pressing steep pasta dough, the intensity of grinding increases, as a result of which the air remaining in the dough turns into microbubbles distributed throughout the dough.
There are two ways to eliminate the extrusion of whitish products on screw presses without vacuuming the dough or with an inefficient vacuuming system. The first is by increasing the pressing pressure, which will contribute to a more complete extrusion of air from the dough when it is compacted in the screw chamber. By cooling the dough by supplying cold water to the jacket of the screw cylinder and thus increasing the pressing pressure, the desired result can be achieved. However, when the dough is cooled, its viscosity increases, which means that the intensity of its grinding increases - the energy consumption for pressing increases, the pressing speed decreases, and the whitish color does not always disappear. More efficient is another way. To do this, increase the plasticity of the dough, in particular, increase the humidity or increase the temperature, but not by grinding the dough, but by preheating it before entering the pressing (high-temperature kneading and molding modes).
Roughness. When using metal matrices without plastic inserts, the surface of the pressed products is less smooth, and if the surface of the forming gap is not sufficiently processed, it becomes rough. This is due to the adhesion of the dough to the surface of the forming gap: the dough layer adhering to it remains motionless, and the next, inner layers move, overcoming the forces of adhesion of the dough particles to each other, breaking away from the adhered layer. As a result, burrs (tears) form on the surface of the products. Sometimes the layer of dough adhering to the forming gap under the influence of certain factors comes off and remains on the surface of the product in the form of a test ring called a “stocking”.
The value of the roughness of the products depends on the degree of adhesion of the dough to the surface of the forming gap and on plasticity: with a more plastic dough, the burrs are tightened, as it were, and the surface is smoother. The dough sticks most strongly to stainless steel, less to brass, and even weaker to bronze. The worse the surface of the forming gap is treated, the stronger the dough sticks, so grinding is mandatory in the manufacture of pasta matrices without fluoroplast.
Pasta dough practically does not stick to fluoroplastic, therefore, when using matrices with fluoroplastic inserts, products with a smooth surface are always obtained.
It should be remembered that a rough surface gives products a whitish color due to the scattering of light rays incident on it. Therefore, even when using flour with a high content of carotenoid pigments, such products will not have an amber yellow color. In addition, when cooking, products with a rough surface will lose a large amount of solids.
To improve the surface condition of pasta, you must:
- use pasta flour;
- use matrices from alloys with increased anti-adhesive ability (bronze, brass);
- install matrices with inserts and rings, inserts made of Teflon (fluoroplast);
- increase the plasticity of pasta dough by changing the humidity by 1-1.5% and the dough temperature in front of the matrix up to 60 ° C - for long ones and 70 ° C for short ones;
- use the high-temperature molding mode with heating the metal matrix up to 100-110 °C or up to 75-85 °C for matrices with Teflon inserts.
Darkening. The reasons for the darkening of pasta products are either the melanin formation reaction or the melanoidin formation reaction, which can occur during the production of pasta with enrichers when using ultra-high-temperature drying modes. Flour of lower grades, flour ground from sprouted or frost grains, has a greater ability to darken. Methods for preventing the browning of pasta products are aimed at inactivating the polyphenol oxidase enzyme. Physical methods: the use of high-temperature modes of kneading, molding, drying, thermoradiation (IR), microwave drying, steaming, preliminary heat treatment. Chemical methods: the introduction of ascorbic acid, sodium chloride.
Swelling, sagging. The causative agents of swelling and souring of pasta products are heterofermentative lactic acid bacteria. Swelling is possible with a strong contamination of flour and water, as well as with a delay in the molded semi-finished product before drying, i.e. in violation of the technological mode of cutting. Lactic acid bacteria ferment sugar flour with the formation of acids, including volatile ones. Pasta has an unpleasant sour taste, smell, increased titratable acidity. On the surface of the products, tubercles of various sizes with voids are observed.
Mold. The cause of mold is an increase in the moisture content of dry pasta above 16% under the action of mold fungi of the genus Aspengillus, Penicillium, Rhizopus, etc. Enzymes of these microorganisms hydrolyze carbohydrates, proteins, lipids. The products have a musty smell, an unpleasant taste, spots and stripes of different colors appear on the surface of the products: white, purple, gray-green, etc. To prevent microbiological spoilage of pasta, it is necessary:
– control the microbiological state of raw materials, equipment, containers, production shops;
- observe the optimal modes of dough preparation, blowing, drying, storage;
— carry out sanitization of equipment, workshops, etc.