Evaluation Of Physico-chemical And Functional Properties Of Composite .

Tharise et al./IFRJ 21(4): 1641-1649Table 1. Different treatment used to prepare compositeflourTreatmentT1T2T3T4T5T6T7T8T9Cassava Flour (%)504540454035403530Potato Starch (%)152025152025152025Soybean Flour (%)4.54.54.59.59.59.514.514.514.5solution for 5 minutes. The soaking solution wasdrained and the thin slices were sprayed in a tray andwere oven drying at 60oC for 10 hours and after whichit was milled into flour. The flours were screenedthrough a 80 mesh sieve. The flours were stored inpolyethylene bags before using.Potato starch preparationThe fresh potato tubers were sorted, washedthoroughly, macerated using grate machine, diluted1:3 w/v with tap water and filtered though cheesecloth.Starch in the filtrate was allowed to settle for 12 hoursat room temperature (27-30oC). The supernatant wasdecanted and discarded while starch were resuspendedin water for 3 hours and kept at room temperature for3 hours to settle. The starch sediment was dried in aconvection oven at 50oC for 12 hours, cooled to roomtemperature. The starch was then sieved through a 80mesh sieve, packed and sealed in polyethylene bagsbefore using.Soybean flour preparationSoybean grains were thoroughly cleaned toremove the dust and other foreign materials. Theclean grains were soaked into water for 6 hours andthen boiled in pressure cooker for 5 minutes. Theywere removed, dehulled and dried in the oven at 50oCfor 24 hours after which they were ground into flourin an electric grinder. The flour were sieved through80 mesh sieve. The flour samples were kept in airtightcontainer before using.Composite flour preparationThe constant percentage of rice flour at 30%due to it’s ability to increase the viscosity elasticityand a solid dough of composite flour (Dautant etal., 2007). The constant percentage of xanthan gumat 0.5% due to its function as a thickening agentand stabilizer to complete the characteristics offree gluten flour (Gambus et al., 2007). The threedifferent intervals of cassava flour, potato starch, andsoybean flour used in composite flours due to focuson the effect of the different ratio of each of flour onthe characteristics of composite flours. Cassava flour(CF) was blended with rice flour (RF) and soybeanflour (SF), potato starch (PS) and xanthan gum(XG) in different combination (Table 1) by using a1643mixer. The composite flour samples were stored inpolyethylene bags. Ingredient and composite floursamples the were analyzed for proximate, physical,functional and pasting properties. Wheat flour (WF)was used as control flour.Physicochemical properties of flourThe chemical analysis of individual flours (WF,CF, RF, SF, PS) and each treatment of compositeflour including moisture content by oven dryingmethod, crude protein by Kjeldahl’s method, crudefat by soxhlet method, ash by dry ashing, crude fiberby gravimetric methods (AOAC, 1995), and totalcarbohydrates obtained by difference. The chemicalused in this study were analytical grade. The colorof ingredient and composite flours were determinedby using a chromameter (Minolta Type CR-300,Japan) and considered the parameters L*, a* and b*.The L* scale ranges from 0 black to 100 white; the a*scale extends from a negative value (green hue) to apositive value (red hue); and the b* scale ranges fromnegative blue to positive yellow.Functional properties of flourThe functional properties of individual andcomposite flour such as water absorption index(WAI), oil absorption index (OAI) and swellingpower were determined by standard methods. WAIand OAI were determined according to the methodsof Valdez-Niebla et al. (1992), Ju and Mittal (1995)and Subrahmanyam and Hoseney (1995) as modifiedby Niba et al. (2001). Flour samples (1 g) weresuspended in 5 ml of water (for WAI) or vegetableoil (for OAI) in a centrifugal tube. The slurry wasshaken on a platform tube rocker for 1 minute atroom temperature and centrifuged at 3000 rpm for10 minutes. The supernatant was decanted anddiscarded. The adhering drops of water was removedand reweighed. WAI and OAI were are expresses asthe weight of sediment/initial weight of flour sample(g/g).The swelling power of flours were determinedbased on a modified method of Leach et al. (1959).Approximately 0.1 g of sample was transferred intoa weighed graduated 50 ml centrifuge tube. Distilledwater was added to give a total volume of 10 ml. Thesample in the tube was stirred gently by hand for 30s at room temperature, and then heated at 60oC for 30min. After cooling to room temperature, the sampleswere centrifuged for 30 min at 3000 rpm. The weightof sediment was recorded.Pasting properties of floursPasting properties of WF, RF, CF, PS andcomposite flour were evaluated with Rapid Visco

1644Tharise et al./IFRJ 21(4): 1641-1649Analyzer (RVA, Model Tecmaster Newport Scientific,Australia). A suspension of 3 g (14% w.b.) of flourin 25 g of distilled water underwent a controlledheating-and-cooling cycle under constant shear whereit was held at 50oC for 1 minute, heated from 50 to95oC at 6oC/minutes, held at 95oC for 5 minutes. Thefollowing data were recorded: pasting parameters oftime from onset of pasting to peak viscosity (P time);temperature at which peak viscosity was reached (Ptemp); peak viscosity (PV); viscosity at the end ofholding time at 95 C or hot paste viscosity (HPV);breakdown (BD) PV-HPV; viscosity at the end ofthe hold time at 50oC or cold paste viscosity (CPV);setback viscosity (SB) CPV-HPV, stability ratio(SR) HPV/PV, and setback ratio (SBR) CPV/HPV.Data analysisData using completely randomized design wasanalyzed using SAS Version 9.2 for windows. Thedata reported in all tables are an average of triplicateobservations subjected to one-way anlysis ofvariance (ANOVA). Differences between the rangeof the properties were determined using the methodof Least Significant Difference (LSD) tests at 95%confidence level (p 0.05).Results and DiscussionPhysicochemical properties of Composite FlourThe chemical composition of individual andcomposite flours are given in Table 2 and Table3, while color characteristics of composite flour areshown in Table 4. From Table 2 it was found that themoisture content of potato starch was higher thanothers, while ash, protein and fat were highest insoybean flour, and the highest fiber content was foundin cassava flour. Chemical analysis of compositeflour (Table 3) revealed that various treatments ofcomposite flours significantly affected the moisture,ash, protein, fat and fiber contents. There weresignificant differences in the colours of compositeflours (Table 4).There were significant differences in the moisturecontents of various composite flours, and weresignificantly lower than that of the control (wheatflour). The moisture content of composite floursamples in the present study ranged from 9.37% to11.94% compared to reported values of 11 to 15%depending upon storage conditions and hygroscopicnature of flour (Shahzadi et al., 2005). The level ofmoisture content in the composite flours were withinthe recommended moisture levels 14% for safestorage. The moisture content should be below 14%Table 2. Chemical composition of potato starch and rice,cassava, and soybean flours as raw materials for compositefloursFlourPotato StarchRice FlourCassava FlourSoybean FlourMoisture(%)15.98 0.3612.85 0.228.51 0.226.63 0.09Ash(% db)0.16 0.050.39 0.051.06 0.064.23 0.09Protein(% db)4.54 0.285.14 0.854.98 0.2113.70 0 .70Fat(% db)0.29 0.100.58 0.100.65 0.0527.15 0.55Fiber(% db)0.47 0.010.74 0.032.62 0.292.35 0.09The values are expressed as the mean of three replicate samples standard deviationTable 3. Chemical composition and color characteristicsof composite flour from rice, cassava and soybean flour,potato starch and xanthan gumFlourT1T2T3T4T5T6T7T8T9WFMoisture(%)11.62 0.24b12.07 0.11 b11.94 0.13 b10.33 0.47 c9.98 0.39c10.16 0.86c9.37 0.01d10.03 0.12 c10.14 0.20c13.32 0.16aAsh(% db)1.08 0.04 a0.87 0.25 c0.75 0.09 c1.05 0.03 ab0.89 0.03 bcd0.99 0.01 bc1.12 0.04 a1.08 0 a1.05 0.02 ab0.75 0. cProtein(% db)5.36 0.90 bcd5.28 0.16 cd4.50 0.55d5.39 1.03 bcd5.37 0.29 bcd4.72 0.50 d6.22 0.07 b5.71 0.28 bc5.37 0.55bcd11.49 0.07 aFat(% db)1.79 0.13e1.56 0.04ef1.33 0.06f2.92 0.15c2.23 0.27d2.64 0.25c4.91 0.16a4.26 0.28b4.14 0.05b2.12 0.04dFiber(% db)1.94 0.07a1.89 0.03a1.13 0.06c1.93 0.06a1.34 0.01b1.35 0.06b1.40 0.04b1.32 0.07b1.31 0.06b1.31 0.10bThe values are expressed as the mean of three replicate sampels standard deviation.Values with similar superscripts in a column do not differ significantly (P 0.05)Table 4. Color characteristics of composite flour from rice,cassava and soybean flour, potato starch and xanthan gumFlourT1T2T3T4T5T6T7T8T9WFL*96.67 0.08 b96.74 0.20ab97.10 0.59 a96.52 0.11 bc96.30 0.02 c96.29 0.23 c95.88 0.06 d95.78 0.05 d95.71 0.07 d95.02 0.01 eColora*-0.73 0.06a-0.79 0.04b-0.87 0.01c-0.98 0.01d-1.03 0.03e-1.01 0.01de-1.05 0.01e-1.11 0.02f-1.13 0.00f-0.90 0.01cb*5.83 0.08f5.66 0.05f5.77 0.01f7.27 0.05d7.11 0.09de6.99 0.02e7.92 0.31c8.12 0.11bc8.20 0.16b10.01 0.05 aThe values are expressed as the mean of three replicate sampels standard deviation. Values with similar superscripts in a column do notdiffer significantly (P 0.05)to prevent microbial growth and chemical changesduring storage (Shahzadi et al., 2005).The ash contents of composite flours ranged from0.75-1.12% and were significantly higher than thatin wheat flour. Maximum ash content (1.12%) wasobserved in T7 (40% CF, 15% PS, 14.5% SF) butstatistically was not difference from other treatment,except that in T3 (40%CF, 25%PS, 4.5%SF). Thetreatment of T3 (40% CF, 25% PS, 4.5% SF) had thelowest ash content. The T1 (50% CF, 15% PS, 4.5%SF) and T2 ( 45% CF, 20% PS, 4.5% SF) treatmenthad the higher ash content than T3 (40% CF, 25% PS,4.5% SF) even though they had the same level to thatof soybean flour. In the T1 (50% CF, 15% PS, 4.5%SF) and T2 (45% CF, 20% PS, 4.5% SF) treatment,the cassava flour levels were higher than that in T3(40% CF, 25% PS, 4.5% SF). It can be concluded thatash content will be increased as the level of soybeanand cassava flour increased.

1645Tharise et al./IFRJ 21(4): 1641-1649Table 3 shows that the protein contentof composite flours in various treatment weresignificantly lower than the wheat flour samples.Among of composite flours the treatment of 40%CF, 15% PS, 14.5% SF (T7) has the highest proteincontent. It was observed that, the protein contentincreased as the level of soybean and cassava flourincreased. This may be due to the high protein contentin soybean and cassava flour compared with potatostarch as shown in Table 2. This similar observationwas made in a research study by Akpapunam et al.(1997) and Olaoye et al. (2006).Fat content of composite flours ranged from1.33% to 4.91% being lowest for T3 (40% CF, 25%PS, 4.5% SF) and highest for T7 (40% CF, 15% PS,14.5% SF). The highest fat content were recordedfor the highest soybean and cassava flour level incomposite flour. The initial fat content of the rawmaterial affected the fat content of the respectivecomposite flour. Soybean flour has the highest fat of27.15% (Table 2).The fibre content obtained in composite flours, asshown in Table 3 ranged from 1.31% to 1.94%. Thehighest fibre content was found in T1 (50% CF, 15%PS, 4.5% SF) treatment and was not significantlydifference than those in T2 (45% CF, 20% PS, 4.5%SF) and T4 (45% CF, 15% PS, 9.5% SF), while thelowest fibre content was found in T3 (40% CF, 25%PS, 4.5% SF). Cassava and soybean flour had thehigher fibre content than those in potato starch andrice flour. At the same level of soybean flour, thehigher fibre content occurs in the higher cassava flourlevel. This is may due to the higher fibre content inthe cassava flour than that in soybean flour.The color of the composite flours wassignificantly whiter but less red than that of wheatflour (Table 4). All of the composite and wheat floursin this study were more green as shown in negativevalue of b*. The highest and the lowest L* value orwhite color were found in T3 (40% CF, 25% PS, 4.5%SF) and T9 (30% CF, 25% PS, 14.5% SF), respectively.It can be noted that the L* value decreased as the levelof soybean flour increased. The color of compositeflour depends on the soybean flour level.Functional properties of composite floursThere was no significant in water absorptionindex of composite flours and wheat flour (Tabel5), but in oil absorption index and swelling powerthere were significant differences among compositeflours and wheat flour. Water absorption index forcomposite flour ranged from 2.36 g/g for T7 (40%CF, 15% PS, 14.5% SF) and 2.63 g/g for T6 (35%CF, 25% PS, 9.5% SF), while in wheat flour 2.12Table 5. Functional properties of composite floursFlourT1T2T3T4T5T6T7T8T9WFWater Absorption Index(g/g)2.53 0.22a2.53 0.17a2.62 0.03a2.45 0.14a2.59 0.43a2.63 0.04a2.36 0.01a2.44 0.00a2.53 0.01a2.12 0.02aOil Absorption Index(g/g)2.08 0.17a2.03 0.07ab1.87 0.01c1.92 0.07bc1.93 0.05bc1.88 0.06c1.94 0.00abc1.94 0.02abc2.05 0.06ab2.02 0.10aSwelling Power(g/g)9.63 0.07 c10.86 0.16b12.21 0.05a8.15 0.57d9.16 0.29c9.62 0.30c4.27 0.32f4.46 0.20f6.75 1.11e7.13 0.89eThe values are expressed as the mean of three replicate sampels standard deviation.Values with similar superscripts in a column do not differ significantly (P 0.05)g/g. There was also minimal variability in waterabsorption index among the composite flours. Waterabsorption index is an important processing parameterand has implications for viscosity. It is also importantin bulking and consistency of products, as well as inbaking application (Niba et al., 2001).Oil absorption index of composite flours rangedfrom 1.87 g/g for T3 (40% CF, 25% PS, 4.5% SF)to 2.08 g/g for T1 (50% CF, 15% PS, 4.5% SF). Thehighest oil absorption index for composite flour wasfound in T1 (50% CF, 15% PS, 4.5% SF) and did notdiffer significantly with T2 (45% CF, 20% PS, 4.5%SF), T7 (40% CF, 15% PS, 14.5% SF), T8 (35% CF,20% PS, 14.5% SF), T9 (30% CF, 25% PS, 14.5%SF) and wheat flour, while the lowest oil absorptionindex was found in T3 (40% CF, 25% PS, 4.5% SF)and did not differ significantly with T4 (45% CF, 15%PS, 9.5% SF), T5 (40% CF, 20% PS, 9.5% SF), T6(35% CF, 25% PS, 9.5% SF), T7 (40% CF, 15% PS,14.5% SF) and T8 (35% CF, 20% PS, 14.5% SF).These results showed that the oil absorption index ofcomposite flour were affected by soybean and cassavaflour level. In T1 and T2 although the soybean flourlevel were lower than T4 (45% CF, 15% PS, 9.5%SF), T5 (40% CF, 20% PS, 9.5% SF), and T6 (35%CF, 25% PS, 9.5% SF) but the cassava flour levels inthese treatment were higher than T4 (45% CF, 15%PS, 9.5% SF), T5 (40% CF, 20% PS, 9.5% SF) and T6(35% CF, 25% PS, 9.5% SF). In the treatment of T7(40% CF, 15% PS, 14.5% SF), T8 (35% CF, 20% PS,14.5% SF) and T9 (30% CF, 25% PS, 14.5% SF) thesoybean flour level were higher than other treatments.The oil absorption index is influenced by the lipophilicnature on the granula surface and interior whichwere influenced for functional properties of starches(Babu and Parimalavalli, 2012). The major chemicalaffecting oil absorption index is protein, which iscomposed of both hydrophilic and hydrophobicparts. Non-polar amino acid side chains can formhydrophobic interactions with hydrocarbon chainsof lipid (Eltayeb et al., 2011) and has implication infunctional properties of flours. Oil absorption indexis importance since oil acts as flavor retainer and

Tharise et al./IFRJ 21(4): 1641-16491646Table 6. Pasting profile of composite fluorsFlourT1T2T3T4T5T6T7T8T9WFPtemp (oC)72.02 0.03 a71.78 0.23 a71.62 0.03 a72.05 0.00 a71.88 0.25 a71.38 0.28 a72.07 0.03 a72.05 0.00 a71.35 0.22 a77.80 10.58 aPV (Cp)4266.67 53.98 b4423.00 11.36 a4347.00 52.09 a3124.00 90.27 c3019.00 37.64 d3107.00 97.78 cd2311.67 23.80 f2358.00 36.43 ef2390.67 8.02 ef2433.00 46.29 eHPV (Cp)1864.00 11.53 b1985.33 14.57 a1975.33 18.01 a1597.00 34.00 c1506.00 18.52 d1575.00 39.96 c1313.67 24.09 fg1353.00 28.62 f1398.67 10.07 e1281.67 20.50 gBD (Cp)2402.67 42.77 ab2437.67 4.73 a2371.67 34.27 b1527.00 56.43 c1513.00 43.58 c1532.00 58.21c998.00 11.41 e1005.00 8.54 e992.00 18.08 e1151.33 28.38 dSB (Cp)CPV (Cp)SR1199.33 29.74 f 3063.33 19.86 c 0.44 0.00 e1320.00 10.39 e 3300.00 12.53 c 0.45 0.00 e1439.67 11.02 bc 3415.00 27.87 a 0.45 0.00 e1234.00 32.74 f 2831.00 66.36 de 0.51 0.00 d1363.67 3.51 d 2869.67 16.92 d 0.50 0.01d1556.33 49.57 a 3131.33 88.95 c 0.51 0.00 d1305.00 17.00 e2618.67 14.36 f 0.57 0.01 b1415.67 11.93 c 2768.67 37.61 e 0.57 0.00 b1478.67 10.69 b 2877.33 11.06 d0.59 0.0 a1311.33 18.50 e2593.00 39.00 f 0.53 0.00 cSBR1.64 0.02 g1.66 0.01 g1.73 0.00 f1.77 0.01 e1.91 0.01 d1.99 0.01 c1.99 0.03 c2.05 0.02 ab2.06 0.01 a2.02 0.00 bPtemp pasting temperature, PV Peak viscosity, HPV hot paste viscosity, BD Breakdown viscosity, B setback viscosity, CPV cold paste viscosity, SR Stability ratio, SBR setback ratio.The values are expressed as the mean of three replicate sampels standard deviation. Values with similar superscripts in a column do not differ significantly (P 0.05)increase the mouth feel of foods, improvement ofpalatability and extension of shelf life particularlyin bakery or meat products where fat absorptions aredesired (Aremu et al., 2007).Swelling power in the composite flours rangedfrom 4.27 g/g for T7 (40% CF, 15% PS, 14.5% SF)to 12.21 for T3 (40% CF, 25% PS, 4.5% SF). Therewere significant differences in swelling power amongformulation treatments of composite flour as well aswheat flour. Swelling power decreased as the levelof soybean flour increased, but in the same level ofsoybean flour, the swelling power increased as thelevel of potato starch increased and cassava flourdecreased. Swelling power is often related to theirprotein and starch content (Woolfe,1992). A higherprotein content in flour may cause the starch granulesto be embedded within a stiff protein matrix, whichsubsequently limits the access of the starch to waternd restricts the swelling power (Aprianita et al.,2009). The amylopectin is primarily responsible forgranule swelling, the higher amylopectin content incomposite flour with higher level of potato starchwould increase the swelling power of compositeflour (Tester and Morrison, 1990). Moorthy andRamanujam (1986) reported that the swelling powerof granules is an indication of the extent of associativeforces within granule.Pasting properties of composite floursTable 6 shows the pasting profile of compositeflours as well as wheat flour. The pasting temperatureis an indication of the minimum temperature requiredto cook or gelatinize the flour (Kaur and Singh,2005). There were no significant differences inpasting temperatures between various treatments ofcomposite flours as well as wheat flour, but in generalthe pasting temperature in composite flours werelower than that of wheat flour. This may be due to theaddition of xanthan gum in composite flours. Theseresults are in accordance with those reported by Hoand Noor Aziah (2013) that the addition of xanthangum to composite flour blends gives a lower pastingtemperature.The results of the pasting characteristics indicatethat the higher level of soybean flour reduced thepeak viscosity (PV), hot paste viscosity (HPV), breakdown viscosity (BD) and cold paste viscosity (CPV)of composite flour this due to the present of fat fromsoybean flour that decrease the viscosity (Dautant etal., 2007). In general the viscosity of composite flourwas higher than wheat flour, but at the soybean levelof 14.5% it was found that the viscosity of compositeflour was quite similar with that of wheat flour. Theaddition of xanthan gum in composite flour may beattributed to the higher viscosity than wheat flour (Hoand Noor Aziah, 2013).The PV of composite flours ranged from 2311.67cP for T7 (40% CF, 15% PS, 14.5% SF) to 4347.00 cPfor T3 (40% CF, 25% PS, 4.5% SF). At the level ofsoybean flour 14.5%, the PV value was not differencesignificantly with that of wheat flour. The relativelylow peak viscosity in the higher level of soybean incomposite flour indicates that the flour may be suitedfor products requiring low gel strength and elasticity(Abioye et al., 2011).The HPV is the minimum viscosity valuemeasur

from cassava, rice, potato, soybean and xanthan gum as alternative of wheat flour Abstract This work aims at examining the physical, chemical and functional properties of composite flour produced with cassava, rice, soybean flours, and potato starch and added with 0.5% xanthan gum. Nine blends of composite flours were prepared by homogenously .