Yield per cent
The yield per cent of EAP recorded in between 60.674±0.78 to 65.566±0.95 per cent (Table 1). The samples of T
3 group recorded the highest yield while that of T
4 recorded the lowest. This might be due to high fiber content in oat flour (3.53-5.87%).
(Youssef et al., 2016) and relatively higher moisture content in JRF (6.58-22.68%),
(Roy et al., 2010) which was added at the rate of 8%, while in T
4 it was added at 4% along with GRF (7.21% moisture),
(Qin et al., 2016). Statistically, only the T
4 sample differ significantly (P<0.05) in yield percentage from the other samples studied. However, the per cent yield recorded in the study was somewhat higher than those reported by
Deepthi et al., (2011) who had prepared EAP by incorporating WF and rice flour (RF).
Proximate composition
Moisture
A significant differences
P<0.05 in the moisture content were observed between control and T
1 in comparison with other formulations. The T
1 formulation recorded highest per cent (52.98±1.00) while T
2 formulation recorded lowest 44.35±0.73% (Table 1), which might be due to the incorporation of both the varieties of rice flours
i.e., Glutinous and Joha at 10% each in T
1 formulation, which are having a higher moisture contents of 7.21 and 6.58-22.68%, respectively
(Qin et al., 2016; Roy et al., 2010) and also superior water binding capacity
(Lee et al., 2004). The lowest moisture content in T
2 group might be due to the addition of more amount of oat flour with lower moisture content (9.96-10.47%)
(Youssef et al., 2016) as compared to the control containing rice and wheat flour with a moisture content of 12.08 and 12.67%, respectively
(Thomas et al., 2013; Kulkarni et al., 2012).
Crude protein
The formulations (T
2, T
3 and T
4) differed significantly (P<0.05) from control and T
1 formulation in having a higher CP content (Table 1). Highest CP was recorded in T
2 and lowest in T
1 formulation. Such high percentage of CP might be ascribed to high protein content in oat flour
i.e., 11.61-13.62%
(Youssef et al., 2016) added at 12% level as compared to the control with a protein content of 5.96% in rice flour
(Thomas et al., 2013) and 10.55% in Wheat flour
(Kulkarni et al., 2012)..
Crude fat
Ether extract content differed significantly between (
P<0.05) control and T
1 as compared to other formulations of EAP. The higher Ether Extract content in T
4 formulation might be due to the incorporation of oat, joha and glutinous rice flours, which have higher fat content (7.23-8.92%, 2.03-2.88% and 0.71%, respectively),
(Roy et al., 2010; Youssef et al., 2016; Qin et al., 2016) as compared to others. The lowest EE content registered in the control formulation might again be a reflection of very low fat content in wheat flour (0.94%),
Kulkarni et al., 2012) added at 15% level along with 5% level of rice flour (1.24% crude fat),
(Thomas et al., 2013). A lower EE per cent was reported by
Deepthi et al., (2011) for dehydrated EAP, which might be due to the differences in varieties of rice and wheat incorporated as flours in EAP preparation.
Total ash
The present study revealed a highly significant differences (
P<0.01) between the different formulations for ash content. The highest TA per cent was registered in T
3 formulation, which might be due to the addition of oat which contains much higher percentage of ash (2-2.15%)
(Youssef et al., 2016) as compared to other flours incorporated in EAP preparation. On the other hand, the lowest TA registered in Control formulation might be due to the incorporation of rice and wheat flour both of which contains much lower percentage of TA (0.39 and 0.94%, respectively),
(Thomas et al., 2013; Kulkarni et al., 2012).
However, the total ash per cent recorded in the present study was somewhat lower than those reported by
Deepthi et al., (2011) who prepared EAP by incorporating WF and RF.
Texture profile analysis (TPA)
Hardness
A highly significant difference was found between Control and Treatment groups of EAP (P<0.01) (Table 2) for hardness values. Highest value found in T
3 (1.288±0.18) followed by C (0.997±0.02) and lowest in T
1 (0.404±0.04) formulation. This might be due to variation in both fiber and protein content in GRF (6.78% protein),
(Qin et al., 2016), JRF (7.7-9.9% protein),
(Saikia et al., 2012) and oat flours (11-13.62% protein),
(Youssef et al., 2016). Besides, the differences in the moisture content of these flours might have also lead to these differences.
Yang et al., (2009) also reported that moisture content significantly affects the hardness of the food product.
Springiness
Springiness values differed significantly (P<0.05) for the control and treated samples, with the highest score in C (0.577±0.07) followed by T
4 (0.479±0.05) and the lowest in T
1 (0.325±0.02) formulations. Though T
1 formulation recorded higher moisture per cent yet the springiness value was lowest in T
1 formulation. This might be due to the presence of higher fiber content in GRF. The highest springiness recorded in C formulation might be ascribed to lower fiber and also moisture content in WF. Springiness behavior varies significantly with the processing techniques and could be correlated with the influence of moisture in the product
(Hsu and Yu, 1999).
Cohesiveness
No significant differences between control and treatment groups of EAP were found for cohesiveness. Mean value was highest in T
2 (0.715±0.05) and lowest in T
4 (0.537±0.08). Even though T
2 registered a low moisture content, the highest cohesiveness score registered by it might be due to high fiber content in GRF that acted as strong binding agent. The C group exhibited second highest cohesiveness character next to T
1 and this could be due to higher moisture content as compared to T
2 formulation.
Chewiness
Chewiness values differed significantly
(P<0.05) between control and treated groups. The formulation of T
3 (0.412±0.06) was found to be the highest and that of T
1 was the lowest (0.088±0.01). This might be due to the presence of low moisture content in T
3 than that of T
1.
Resilience
For resilience no significant differences was found between control and treated groups. Mean value was highest for T
3 (0.506±0.15) and lowest in T
4 (0.332±0.10) group which might be due to variations in both fiber and protein content in GRF, JRF and oat flours. Besides, differences in the moisture content of these flours might have also lead to the differences.
Colour profile
No significant differences were found among the treatment and control samples for
L* value (Lightness or Darkness),
a*(Redness or Greenness) and
b* Yellowness or Blueness. Nevertheless, the highest mean score for
L* was recorded in T
1 (86.1287±0.2341) and the lowest in C (85.1177±0.5511) group. For
a* score, T
3 group recorded the highest one (0.5567±0.1447) and control group with the lowest (0.1630±0.2584). The score for
b* was highest in control group (17.0610±2.242) and lowest in T
1 group (15.6636±0.4037). The changes in color attributes of the products might have influenced by the processing methods
(Pesek and Wilson, 1986), degree of exposure to light
(Kim et al., 2002) and ingredients interactions
(Osuna-Garcia et al., 1997).
Microbiological qualities
The studies on microbiological qualities of EAP revealed no growth of colonies in total viable plate count (TVPC), total psychrophillic count (TPC) and also for Yeast and Moulds up to 90
th day of storage. This might be due to the presence of albumen protein
i.e. conalbumen in egg albumen that binds iron making it unavailable for bacterial growth and multiplication (Gram positive organisms). The enzyme lysozome of egg albumen also have an anti-bacterial property
(Wang and Shelef, 1991). Addition of mallic acid in EAP preparation have anti-fungal property inhibiting the growth of yeast and moulds.
Deepthi et al., (2011) also evaluated the microbiological quality of EAP prepared by incorporation of Wheat flour (WF) and Rice flour (RF) and stored for 6 months at 27±2°C. They recorded standard plate count (SPC) and Yeast and Mould counts fluctuate within the range of 0.90±0.05 to 3.25±0.05 and 0.84±0.04 to 2.52±0.33 log cfu/g respectively during the storage period. This discrepancy might be primarily due to the difference in the storage temperature of EAP which was 5-7°C in the present study besides, differences in the quality of ingredients used (GRF and JRF) and their incorporation levels in EAP preparation.
Sensory evaluation
Though, no significant differences were observed in respect of appearance, colour, flavour, texture and overall acceptability scores among the control and treatment groups (Table 3) the control group of EAP (incorporation of 15% wheat flour and 5% rice flour) recorded the lowest sensory evaluation scores for all the eating quality parameters. The relatively better appearance and colour scores recorded in T
1 formulation (GRF 10% and JRF 10%) might be due to the correct matching of colours of rice flours with that of Egg Albumen. The T
3 formulation with better flavour scores might be attributed to incorporation of JRF alongwith oat flour in EAP preparation. Highest texture score in T
2 formulation signifies more fineness of the product. The highest overall acceptability score in T
3 formulation might be primarily related to its superior flavour quality imparted by incorporation of JRF.