Evaluation of Physical, Chemical and Sensory Properties of Turkish Flat Breads (Bazlama and Yufka) Supplemented with Lupin, Buckwheat and Oat Flours

In this research, lupin, buckwheat and oat flours (30%) and their blends (15%+15% and 10%+10%+10%) were used in Turkish flat breads (bazlama and yufka) p roduction for nutrit ional enrichment. Some physical (diameter, thickness, spread ratio and color), chemical (moisture, ash, crude protein and mineral content) and sensory properties of bread samples were investigated. High protein levels of lupin flour (LF) increased the protein content of bazlama and yufka samples from 11.85% and 11.62 % to 19.97% and 19.74 %, respectively. The highest ash content was obtained with addition o f 30% buckwheat flour (BF) in flat breads. Generally all of the minerals in breads containing LF, BF and oat flour (OF) or their blends were found significantly h igher (p<0.05) than that of control breads. BF addition increased the darkness and redness of the bread samples. While the lowest sensorial scores for flat breads were obtained with 30% LF or 15% LF+15% OF addition, bazlama containing 30% OF or 10% LF+10% BF+10% OF and yufka containing 30% OF or 15% LF+15% BF or 10% LF+10% BF+10% OF appreciated with higher rates after control breads by panelists. Considering physical, chemical and sensory properties of flat breads, it can be concluded that LF, BF and OF can be used at 10% LF+10% BF+10% OF levels successfully for both bazlama and yufka production.


Introduction
Bread has a great impo rtance in human nutrition as a protein and carbohydrate source. In Turkey, cereal based products especially bread has great importance in diets, 66% of the energy consumed per capita is supplied fro m cereals and 56% of this energy is supplied only fro m breads [1]. There are so many flat bread types all over the world known with d ifferent names such as chapatti, tortilla, tandoori, p ita, baladi, taboon, lavash etc. [2]. Bazlama and yufka are the traditional flat bread types of Turkey. Bazlama is single layered, leavened, circu lar flat bread with creamy yellow color. It has average 3 cm thickness and diameters ranging fro m 10 to 20 cm [3]. Yufka is single layered but unleavened bread with 1-2 mm thickness, 40-50 cm diameters and cream-color surface [4], [5] .
Lupin (Lupinus albus spp) as a valuable ancient legume contains comparat ively h igher amount of protein (about 40%by weight) than cereals and other legu mes except soy.
Lysine content of lupin proteins is high whereas methionine content is low.
Oat is known with its high β-glucans content (2.2-7.8%) which is soluble dietary fibre [18], B co mplex v itamins, protein, fat and minerals [19]. Cereal β-glu kan usage, increase the functional quality of foods. It reduces the blood glucose, cholesterol and triglyceride level. It also protect humans against colon cancer [20], [21].
Considering nutritional and functional properties, lupin, buckwheat and oat flour has a high potential to be used in different foods.
Due to the being of basic food in our diet, it is aimed to increase the nutritional and functional quality of flat breads by the incorporation of LF, BF and OF.

Materials
Buckwheat groats (without hull) were obtained fro m Yar Gıda, Antalya, Turkey. Lupin (Lupinus albus L.) seeds were purchased fro m local market as tradit ionally debittered. Wheat flour, salt, sugar, fresh yeast and oat were purchased fro m local markets in Konya. Buckwheat, lupin seeds (after drying at 60 o C for 24 hr) and oat were ground in a hammer mill (Falling Nu mber-3100 Laboratory M ill; Perten Instruments AB, Huddinge, Sweden) to obtain wholegrain flour.

Bazlama and Yufka Preparation
Flat bread samples were prepared according to Akbaş [24], Başman and Kö ksel [4] respectively by using the formulat ions in Table 1. LF, BF and OF were rep laced with wheat flour at 30%, 15%+15% and 10%+10%+10% levels in both bazlama and yufka samp les. All the ingredients were mixed in a Hobart mixer (Hobart N50, Canada Instruments, North York, Ontario, Canada) for optimu m dough development.
For bazlama preparing, doughs were fermented for 1 hour at 30℃ and divided into two equal pieces and shaped with hand like a ball and allowed to rest for 6 minutes at room conditions. After that, doughs were sheeted to final thickness of 10 mm by using stainless steel circle o f 17 cm diameter and baked at 280 ± 5℃ on p reheated sac for 5 minutes (1500 W).
For yufka samp les, after mixing, doughs were allowed to rest at 30℃ for half an hour and div ided into four equal pieces, shaped like a ball, sheeted by hand rolling to the 1 mm thickness with the aid o f their own flour. After sheeting, it was baked on preheated sac 280 ± 5℃ for 1 min.
Baked bazlama and yufka samples were cooled at room temperature for 1 hour and after physical measurements and sensory evaluation, samples were stored in plastic bags for chemical analyses.
The color o f flours and bread samples was evaluated by measuring the L*, a* and b* values using a Minolta CR-400 (Konica M inolta Sensing, Inc., Osaka, Japan). Saturation index (SI) ((a* 2 + b* 2 ) 1/2 ) of the samples were calcu lated.

Chemical Analyses
The samples were analyzed for their moisture, ash, crude protein using AACC standard methods [25].
The mineral (Ca, Cu, Fe, Mg, Mn, P, K and Zn) contents of the samples were determined by an Inductive coupled plasma atomic emission spectrometry (ICP-A ES) (Vista series, Varian International A G, Zug, Swit zerland) as given by Bubert and Hagenah [26].

Sensory Analyses
Bazlama and yufka samp les were evaluated by 12 panelist who are familiar to flat breads. The sensory quality characteristics of bazlama (appearance, shape and symmetry, texture, mouthfeel, taste and odor, overall acceptability) and yufka samples (appearance, elasticity, mouthfeel, taste and odor, overall acceptability) were evaluated on a 1-9 scale where 1 represented "dislike extremely", 4-5 represented "acceptable" and 8-9 represented "like extremely".

Statistical Analyses
All data were subjected to analysis of variance (ANOVA) and Student's t comparison test. Statistical analyses were performed using the Statistical software JMP 5.0.1 (SAS Institute).

Raw Materi al Properties
The analyses results of flours used in the production of bazlama and yufka are presented in Table 2. The ash content of BF was significantly higher (p<0.05) than that of other flours. LF had higher protein and mineral content (especially Ca, Cu, Fe, Mn, P and Zn) according to BF and OF. A lso, BF was found to be a good source for Mg and K minerals. Literature knowledge confirmed our ash, protein and mineral analyses for different flours [6], [27], [28], [29].
As expected, BF gave the lowest L*(lightness) and the highest a*(redness) values. The highest b* (yellowness) value was obtained with LF due to the natural seed characteristics. It is reported by Doxastakis et al. [27] that the yellow colors of the LF have a considerable appeal and would be a value in many foods.

Pyhsical Properties of Bazl ama and Yufka
The diameter, th ickness and spread ratio of flat breads are summarized in Table 3. The usage of LF, BF and OF or their blends did not significantly (p>0.05) affected the dia meters of bazlama samples, but decreased thickness and increased spread ratio. The lowest thickness and highest spread ratio values were obtained with LF supplemented bazlama samp les.
Yıldız [30] reported that BF usage (0-30 %) in bazlama formulat ions did not significantly affected the diameter and thickness of the samples. In present study, usage of LF, BF and OF or their b lends decreased the diameter and spread ratio of yufka samp les. While 15% LF+15% OF and 10% LF+10% BF+10% OF gave higher diameter and spread ratio after control samp les, 15%LF+15%BF caused the highest decrement in these parameters in yufka samples.

3.3.Chemical Compositions of B azlama and Yufka
Chemical co mpositions of flat bread samp les are given in Table 4. The moisture content of bazlama and yufka samples with 15% BF+ % 15 OF and 15% LF+15% OF were not found significantly different (p>0.05) co mpared to control.
The usage of BF at 30% level increased the ash content of bazlama and yufka samples fro m 1.25% and 1.20% to 1.71% and 1.65%, respectively. In the literature, it is reported that the ash content of spaghetti and tarhana increased with the addition of BF due to the rich ash content of BF [6], [29]. Protein contents of bazlama and yufka samples were found between 11.85% and 19.97%; 11.62% and 19.74%, respectively. The highest protein value was obtained with the addit ion of LF in both bazlama and yufka samples. Jayasena et al. [31] reported that there was 42% increment in protein content of instant noodles by replacing only 20% wheat flour with LF. A lso Ballester et al. [32] found the increment in protein content of the cookies up to 55.7% with LF (5-25%) addition.

Mineral Compositions of B azlama and Yufka
Mineral contents of bazlama and yufka samples are given in Table 5. The rich mineral content of LF, BF and OF caused to increase in mineral content of flat breads. The increments in bazlama and yufka samp les with 30% LF supplementation were found as 2. It is reported that the lupin enriched pasta samples showed higher amounts of protein, Ca, P, Mg and Zn content than control pasta [33]. Bilgiçli [29] found increments in the mineral contents (especially K, Mg and P) of tarhana samples with the addition of BF. In the study conducted by Tamime et al. [34] Mn, P and Mg content of Kishk samp les made fro m oat varieties were found higher than that of barley and wheat. In another study, it is reported that K, Ca and Fe contents of couscous prepared with oat flour were higher than that of traditional couscous and couscous with eggs [35].

Color val ues of bazl ama and yufka
Color values of samples are presented in Table 6. Raw material colo rs directly affected the color of flat breads. The lowest L* values were observed in 30% BF and 15% BF+15% OF bazlama and yufka samples. Bilg içli [29] and Lin et al. [36] reported that BF enriched tarhana and bread had lower L and higher a and b values than that of control products. The natural dark pig mentation of whole BF and the tendency of BF on Maillard reaction could be effective on this color change [37]. The usage of LF increased the b*(yellowness) values of bazlama and yufka samples at all addition levels. Similarly, it was reported that the crumb colors of breads prepared with LF became more yellowish [27]. Generally b* and SI values showed same tendency, the highest SI values were found in LF at 30% levels.

Sensory Properties of Bazl ama and Yufka Samples
The sensory scores of bazlama and yufka samp les are presented in Table 7 and 8. Enriched bazlama samples prepared with the addition of OF at 30% level and blends of LF, BF and OF at equal ratios (10%) were scored higher for their appearance, shape and symmetry, texture, taste and odor after control b read. Yu fka samp les produced with 30% OF or 15% LF+ 15% BF or the b lends of LF, BF and OF at equal ratios (10%) gave high overall acceptability scores. Supplementation of breads with 30% LF or 15% LF + 15% OF gave the lo west sensory attributes in flat breads. The highest decrement on taste and odor scores of bazlama and yufka samp les was found at 15%LF +15%OF and 30% BF addition respectively.

Conclusions
In the present study, bazlama and yufka (Turkish flat breads) enriched with LF, BF, OF and the effects of these flours on the physical, chemical and sensory properties of breads were investigated. The rich composition of LF, BF and OF improved the nutritional quality of bazlama and yufka samp les in terms of ash, protein and mineral content (Ca, Cu, Fe, Mg, Mn, P, K, Zn ). The yello w color of LF and dark colo r of BF d irectly affected the surface color of bazlama and yufka. It can be concluded from the results of this study that acceptable bazlama and yufka can be produced by the addition of the LF, BF and OF at equal ratio (10%).