COMPARISON OF ALVEOGRAPH CHARACTERISTIC OF FLOUR OBTAINED FROM DIFFERENT TYPES OF COMMON WHEAT AND SPELT WHEAT
D. Zhygunov, I. Toporash, Y. Barkovska, Y. Yehorshyn
Zernovì Produkti ì Kombìkorma
Practice of processing of new types of wheat is widespread in the world, but it's almost unknown in the CIS countries, because selection for many years aimed at obtaining exclusively high protein bread-baking varieties of wheat. But not known what technological properties of flour possesses from wheat types of a special intended purpose, and that it's necessary to consider when conducting varietal grinding of such raw material. The alveograph measures the viscoelastic properties of wheat flour.
... According to the standard method ISO 27971 the amount of added water is initially calibrated directly as a percentage of dough moisture. This method is designed for standard types of flour and may not be suitable for evaluating the rheological properties of flour with different water absorption capacity. To find out the properties of new types, standard methods may not be suitable, therefore, methods should be studied and adapted if necessary. To investigate the relationship between water absorption capacity and viscoelastic properties of the dough, alveograph tests were conducted on eight flour samples obtained from different types of wheat. The studies were performed using a standard test (calculated for WAC of flour = 53%) and a test with adaptive moistening, for which the amount of added water was calculated according to the water absorption capacity (WAC) of the flour, which was determined on mixolab. Flour from common red wheat (Kuyalnik) is the benchmark of common bakery wheat and according to the results of standard alveogram has the highest strength (W) and elasticity (Ie) of all samples. The wheat with W= 43910-4J corresponds to strong wheat (W>20010-4J). The addition of water in accordance with the WAC softens the dough W=26010-4J, but it's still optimal for bakery purposes. The results of studies of common black wheat (Chornobrova) correlate with the results of wheat Kuyalnik, but the baking properties were worse. For waxy wheat (Sofiika), the test on the alveograph with adaptive moistening gave her more water, which led to an increase in elasticity (Ie=52.4%) and extensibility (L=77 mm) and became closer to an optimal P/L ratio (0.74) that was more suitable for the bake bread (0.8-1.2). Flour from soft wheat is expected to have average baking properties (W>15510-4J), but in all respects it is slightly better than Chornobrova. Adaptive moistening, unlike the sharp deterioration of rheological characteristic of Chornobrova, does not alter the properties of the Belyava and Oksana dough, due to the low WAC value (53.8% and 54.0%). Spelt wheat flour has low strength(W<6210-4J), lower P/L ratio 0.25-0.50 and unsuitable (fluid, sticky) test consistency. All samples of Spelt with adaptive moistening showed similar result – its decrease of P indicator and increase of extensibility (L). In a result we observe decrease of P/L ratio to 0.18-0.29, thus indicating extremely extensible doughs with very little elasticity. For all samples, with adaptive moistening a decrease in resistance to extension (P) and an increase in extensibility (L) are observed, in a result of the decline in the P/L ratio. Adaptive moistening for common wheat (Kuyalnik) will show the change in P and L and the P/L ratio in real cooking conditions, since the standard alveograph test assesses only the potential of wheat. By adjusting the amount of water, we can achieve optimal dough characteristics for different products. For soft and spelt wheat, adaptive moistening is not necessary, because the WAC and moisture content are the same, and according to the standard of the experiment. It is advisable to carry out an alveograph test with adapted moistening for waxy wheat, that giving it more water, which leads to an increase in elasticity and extensibility, as a consequence, and leading to an optimal P/L ratio that was more suitable for the bake bread (0.8-1.2). Based on its special application, it is necessary to develop specific recommendations for determining its properties on the alveograph.