Dough farinographs

The Farinograph-E (Figure 6) uses a PC to process the data from the Farinograph this is a considerable improvement over measuring pieces of paper from a chart recorder. The software supplied runs under Windows and can multi-task so that one PC can handle data from several instruments. This is particularly convenient as the Farinograph is used to prepare doughs for the Extensograph. 

Farinograph doughs only contain flour and water, so the water absorption obtained is a theoretical value. The value obtained from the same batch of flour in a bread dough will always be lower. When the Farinograph is used to prepare doughs for the Extensograph, the doughs do contain flour, salt and water. 

The major use of the Farinograph in a bakery laboratory is to prepare doughs for the Extensograph. 

Figure 8-29 Typical Farinograph Curve. (A) Arrival time, (B) peak time, (C) stability, (D) departure, (E) mixing tolerance index, (F) 20-minute drop. Source From H.P. Wehrli and Y. Pomeranz, The Role of Chemical Bonds in Dough, Baker s Digest, Vol. 43, no. 6, pp. 22-26, 1969.

Four formulations were used to produce French bread dough with different ascorbic acid quantities, as listed in Table 27.1. AACC 54-21 (AACC, 1995), a commercial bakers flour (Moinho Pacifico, Brazil) with a water content of 13.60% and farinograph water absorption of 65.60%, was used for all formulations. 

The Brabender Farinograph measures and records the resistance of dough to mixing as it is formed from flour and water, developed and broken down. This resistance is called consistency. The maximum consistency of the dough is adjusted to a fixed value by... 

Fig. 2. Representative farinogram showing some commonly measured indexes. A consistency of 500 farinograph units (FU) corresponds to a power of 68 and 81 W per kilogram of dough in mixtures for 300 and 50 g of flour, respectively (Bloksma Bushuk, 1988).

FIGURE 15.5 The farinograph used to assess rheological properties of wheat dough, with its corresponding curve (photograph courtesy of Guadalupe A. Lopez-Ahumada, DIPA, Universidad de Sonora, Mexico). 

Determine arrival time, departure time, dough development time, dough stability, and mixing tolerance index of the following farinograph curve. In you opinion, what sort of flour is it What kind of products can you make with this flour ... 

Arrival time, farinograph Time required for the farinograph dough to first reach a consistency of 500 farinograph units. It is related to the water absorption capacity of the wheat flonr and the dough rheological properties. 

Dough stability Farinograph parameter estimated by subtracting departure time from arrival time or the time in which the dough has a consistency of 500 FU. The dough stability is closely related to flour and bread quality. Generally, hard wheat flours have higher stability compared to all-purpose and soft-wheat flours. 

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