Influence of fenugreek seeds flour on the rheological characteristics of wheat flour and biscuit quality

الملخص EN

Nowadays, demand for health-oriented products such as functional foods which has
high fiber products is increasing.

So, this work studied the effect of partial replacement of wheat flour
(72% extraction) by different levels (5% , 10% , 15% and 20% ) of raw, soaked and germinated
fenugreek seed flour (Trigonella foenum graecum).

The chemical and rheological characteristics for
produced dough blends, and on the sensory, physical and chemical characteristics for produced
biscuits were studied.

Results indicated that incorporation of fenugreek seed flour (FSF) obviously (P≥
0.05) increased in protein, fat, crude fiber, and ash with increasing FSF supplementing levels.

The
mineral contents of treated fenugreek seed flours almost was higher than the control samples.

Germination process of fenugreek seed flour caused a decrease in the most of minerals compared with
the soaking process.

The replacement of wheat flour with fenugreek seed flour caused a decrease (P≥
0.05) in extensibility of the dough as measured by the extensograph and an increase (P≥ 0.05) in
resistance to extension, proportional number and dough energy tests.

Farinograph results showed that
all additions of fenugreek seed flour increased water orption, dough development time and mixing
tolerance index, while decreased dough stability and weakening values in the case of higher replacing
with fenugreek seed flour levels.

The effects on dough development time, water orption, and
mixing tolerance indices were intensified with GF (germinated fenugreek seed flour) samples under
5% or 10% levels.

Generally, the addition of germinated fenugreek flour to wheat flour at ratio of 5 or
10 levels had a less deleterious effect on the chemical and rheological properties of dough than that of
RF(raw fenugreek seed flour) and/or SF(soaked fenugreek seed flour).

The sensory evaluation results
of supplemented biscuit showed that a maximum of 10% FSF can be incorporated to made acceptable
quality biscuits.

While, biscuits containing 15 or 20% FSF were unacceptable to the panelists as
compared with the control biscuit.

Results of chemical analyses indicated that incorporation of FSF
into biscuits formula obviously (p≥0.05) increased each of protein, fat, crude fiber, ash and
indispensable amino acid (IAAs) contents with increasing FSF supplementing levels.

The amino acids
composition revealed that supplemented biscuits with FSF contained the most of IAAs and will cover
a highly percentages of reference protein pattern of FAO/WHO (1973).

Lysine was the first limiting
amino acid in control biscuit samples.

Supplemented biscuits with germinated FSF had higher lysine
contents than other treatments.

It could be concluded that, incorporation up to a 10% level of
germinated FSF into wheat biscuit formula resulted in improving their chemical, sensory quality
characteristics and complementing the deficiency in lysine amino acid.