OPTIMIZATION OF PARAMETERS FOR DEVELOPMENT OF MALT FROM GRAIN AMARANTHS Raghavananda Nayak, Minati Mohapatra*, U. S. Pal, N. R. Sahoo, M. K. Panda Department of Agricultural Processing and Food Engineering, College of Agricultural Engineering and Technology, OUAT, Bhubaneswar, Odisha Received: 23/10/2017 Edited: 31/10/2017 Accepted: 13/11/2017 Abstract: Amaranths malt was prepared varying different proportions of germinated amaranths (10-30% w/w): ragi: green gram in 50-50 % (by w/w) of the rest; different temperature (60,70,80 C) and time (10,15, 20 min) of roasting following response surface methodology at 3 levels and 3 parameters box behenken design of experiment. Addition of germinated roasted amaranths increased the reducing sugar and ascorbic acid content of the malt, whereas no significant change in protein, fat was observed. Increasing roasting temperature showed increase in reducing sugar, protein and ascorbic acid content initially and subsequently decreased at higher roasting temperature beyond 70 C. However, the fat content of malt decreased with increase in roasting temperature. Roasting time was found to have no significant (p<0.05) effect on the bio-chemical constituents of malt within the range of time studied. From the RSM optimization, it was found that roasted germinated amaranths at 65 0 C for 10 min when added in the proportion of 30% w/w gave maximum ascorbic acid content with less variation in protein, fat and reducing sugar content. Keywords: Germinated amaranths, malt, roasting of amaranths, Protein content, fat content, ascorbic content, proximate composition etc. Introduction Grain amaranth (Amaranthus. hypochondriacus L.) locally known as Ramdana is an underutilized food grain. The crude protein content of grain amaranth varies between 12.5 to 17.6 % (db) which is higher than in most common grains except soybeans. The protein contains around 5% lysine that is usually low in cereals and 4.4% sulfur amino acids, which are usually low in legumes and compares well with the required World health organization (WHO) protein standard. The total lipid content varies from 5.4-17.0% (db) and has a high level of unsaturation (about 75%), containing almost 50 % linoleic acid (Teutonico and Knorr, 1984; Opute, 1979). The anti-nutritional substances such as lectins, phenols, tannins and trypsin inhibitors, which may be present in varying amounts, could be partially or totally degraded by heat treatment. As it is rich in high quality protein and unsaturated fat, possibilities can be exploited to prepare different nutritious value added products like malt, puffed items, extruded products, burfi, cake, chapatti etc from this pseudocereal. Utilization of grain amaranth will help to exploit the market niches for high quality protein foods. Anigo et al., (2010) had prepared complementary food gruels formulated from malted cereals, soybeans and groundnut for use in Northwestern Nigeri to combat malnutrition in infant and growing children. Rathod and Udipi (http://archive.unu.edu/unupress/food/8f131e/8f 131E09.htm) had reported that amaranth grains and leaves can be effectively used at the community or village level for producing low-cost, nutrient-rich weaning mixes. Amaranth is known as "rajgeera" (the King's grain) and is often popped to be used in confections called "laddoos," or "alegria" in Mexico. These are eaten as gruel called "sattoo" or milled into a flour to make chappatis (Singhal and Kulkami 1988). It is used as a popular ingredient in breakfast cereal, malt and even as an alternative or can say as adulteration to poppy seed (postak) by the locals. The high crude protein content in grain amaranth ranging from 12.5 to 17.6 % (db) is rich in lysine (around 5%). This can UGC Approved Journal (Sr. No. 3430 Journal No. 62441) / NAAS Score 2017: 3.23, GIFactor: 0.9 25
be added in other cereals, pulses to enrich the nutritional components. The processing technologies like malting, puffing/popping, extrusion, baking and blending for enrichment could be tried to prepare different nutritious value added products. The feasible process technologies will be helpful for better utilization of this under utilized and under exploited nutritious grain and fetch more profit to the farmers. The objective of the present study is to standardization the process technology for preparation of malt as a value added products from grain amaranth with optimization of different grain compositions, puffing time and temperature. Materials and Methods Grain amaranths spikes were obtained from Central farm, Orissa University of Agriculture and Technology, Bhubaneswar. The spikes were dried and threshed in VIVEK millet thresher-cum-pearler. The threshed grain was sieved in a vibrating sieve to obtain the cleaned amaranths grain. Preparation of malt Malt was prepared using three grain ingredients i.e. grain amaranths, green gram and ragi. The proportion of amaranths flour was varied between 0-30% and rest amount was given as green gram and ragi in 50-50% proportion. Amaranths and green gram were sprouted for 48 h and ragi was sprouted for 24 h at room temperature. All the sprouted grains were dried at 50 o C for 14 h. Dried ragi and green gram were roasted at 100 o C for 10 min and ground to powder (sieve size 40 mesh). Dried grain amaranths were roasted at different temperature and time settings. Germinated green gram and ragi flour were taken in the ratio of 50:50 by weight and different proportions of germinated, dried and roasted amaranths flour was blended (Fig. 1) to it for malt preparation as per treatment given in Table 1 to optimize the biochemical parameters such as protein, fat, ascorbic acid and reducing sugar. The protein and fat content of amaranths malt were determined using Kjeldhal digestion and ether extract methods, (AOAC, 1992) respectively. The reducing sugar and ascorbic acid content of raw, roasted and germinated amaranths flour were determined to study the effect of germination on nutritive value. Results and Discussion Effect of germination on nutritive value of grain amaranths The effect of germination of grain amaranths had an positive improvement in its nutritative value with respect to reducing sugar and ascorbic acid content (Colmenares and Bressani, 1990). The reducing sugar content increased after germination indicating Fig.1 Preparation of Malt from sprouted amaranths hydrolysis of polysaccharides into simpler forms (Colmenares and Bressani, 1984), which was not detected in raw and roasted flour. Ascorbic acid content increased from 2.49 to 5.60 mg/100g by germination process. However, ascorbic acid content significantly (p<0.05) decreased after roasting (Table 1). UGC Approved Journal (Sr. No. 3430 Journal No. 62441) / NAAS Score 2017: 3.23, GIFactor: 0.9 26
Table 1: Effect of germination on nutritive value of amaranths Sample Reducing sugar content (%) Ascorbic acimd content (mg/100g) 1. Raw amaranths flour - 2.49±0.065 2. Roasted amaranths flour - 2.08±0.06 3. Germinated roasted 2.69±0.05 5.60±0.20 amaranths flour CD at 5 % level - 0.16 Optimization of malt compositions supplemented with amaranths The biochemical compositional analysis of malt prepared with different proportions of amaranths (10-30%), roasting temperature (60-80 C) and time (10-20 min) are given in Table 2. Increase in amaranths % increased the ascorbic acid content of the malt, whereas, it was more liable to reduction with increase in roasting temperature (Table 2 and Fig 2). However, roasting time did not show any definite trend (Fig. 2). Similarly, addition of more amaranths content increased the protein content of the resultant malt, whereas, with increase in roasting temperature above 70 C decreased in protein content (Fig. 2) of the malt prepared. The application of high temperature above 70 C may result into protein denaturation which led towards reduction in protein content of the roasted amaranths malt. Similar results were also reported by Muyonga et al., (2014) and Bressani et al., (1987), that heat treatment led to Table 2 Compositional analysis of amaranth us supplemented malt Treat No. Amaranth (%) by w/w Temp. C Time min. Protein (%) a reduction in protein quality and digestibility, the effect being higher in popped than in roasted amaranths samples. Increasing roasting temperature showed increase in reducing sugar, protein and ascorbic acid content initially and subsequently decreased at higher roasting temperature beyond some optimum value. However, the fat content of malt decreased with increase in roasting temperature and increased with increase in roasting time from 10 to 20 minute (Fig. 2). Except the fat content, roasting time was found to have no significant effect (p<0.05) on the other chemical constituents of malt within the range of time studied. From the RSM optimization technique (Fig. 3), it was obtained that roasted germinated amaranths at 65 0 C for 10 min when added in the proportion of 30% gave maximum ascorbic acid content with less variation in protein, fat and reducing sugar content (Fig. 3). Fat (%) Ascorbic acid content(mg/100gm) Reducing sugar (%) 1 30 70 10 12.3 6.58 5.6 2.85 2 10 70 20 11.8 6.38 4.86 2.83 3 20 80 20 10.5 6.13 4.16 ---- 4 10 80 15 8.4 6.04 3.83 ----- 5 20 70 15 12.2 6.64 5.23 3.15 6 30 80 15 9.3 6.08 3.87 --- 7 30 70 20 11.4 6.56 5.58 3.12 8 20 60 10 12.3 6.08 4.83 2.85 9 20 70 15 12.1 6.61 5.14 3.13 10 20 70 15 12.2 6.58 5.23 3.06 11 10 60 15 11.6 6.84 4.72 2.81 12 30 60 15 12.3 7.01 5.65 2.78 13 20 70 15 12.2 6.58 5.32 3.15 14 20 80 10 10.3 6.12 4.01 --- 15 20 60 20 11.3 7.03 4.58 2.83 16 20 70 15 12.1 6.68 5.63 3.01 17 10 70 10 12.2 6.38 5.23 3.08 UGC Approved Journal (Sr. No. 3430 Journal No. 62441) / NAAS Score 2017: 3.23, GIFactor: 0.9 27
Fig. 2 Response surface plots for optimization of malt preparation UGC Approved Journal (Sr. No. 3430 Journal No. 62441) / NAAS Score 2017: 3.23, GIFactor: 0.9 28
Fig. 3 Optimization of parameters for malt preparation with optimum level of bio-chemical constituents Conclusion significant (p<0.05) effect on the bio-chemical Germination of grain amaranths increased the constituents of malt within the range of time studied. reducing sugar and ascorbic acid content of the malt, Roasted germinated amaranths at 65 0 C for 10 min whereas no significant change in protein, fat was when added in the proportion of 30% by w/w and rest observed. Increasing roasting temperature showed 50-50% as green gram and ragi gave maximum ascorbic increase in reducing sugar, protein and ascorbic acid acid content with less variation in protein, fat and content initially and subsequently decreased at higher reducing sugar content. The prepared malt from roasting temperature beyond 70 C. However, the fat germinated amaranths could be a better supplement to content of malt decreased with increase in roasting coup up with malnutrition in children and grown temperature. Roasting time was found to have no persons. References Anigo, K.M., Ameh, D.A., Ibrahim S and Danbauchi, S.S. 2010. Nutrient composition of complementary food gruels formulated from malted cereals, soybeans and groundnut for use in North-western Nigeria. African Journal of Food Science Vol. 4(3), 65-72. Association of official analytical chemists. 1992. Official Methods of Analysis, 14th ed. The Association: Washington, DC. Bressani R., Kalinowski L.S., Ortiz M.A., Elías L.G. 1987. Nutritional evaluation of roasted, flaked and popped Amaranths. caudatus., Arch Latinoam Nutr.,37(3), 525-531. Colmenares De Ruiz A.S. and Bressani R.1990. Effect of Germination on the chemical composition and nutritive value of amaranthus grain. Cereal Chem., 67(6), 519-522. Muyonga, J.H., Andabati, B. and Ssepuuya.G. 2014. Effect of heat processing on selected grain amaranth physicochemical properties, Food Sci Nutr., 2(1), 9 16. Opute, F.I. 1979. Seed lipids of the grain amaranths. J. Ext. Bot. 30:601-609. Paredes-lopez, O., and Mora-escobedo, R. 1989. Germination of amaranth seeds: Effects on nutrient composition and color. J. Food Sci. 54:761-75 Rathod K.and Udipi. S.A.The nutritional quality and acceptability of weaning foods incorporating amaranth. http://archive.unu.edu/unupress/food/8f131e/8f131e09.htm. Singhal S. and Kulkami R.K.1988. Review: Amaranths-an underutilized resource. International J of Food Science and Technology, 23, 125-139. Teutonico R.A. and Knorr D. 1984. Plant tissue culture: Food applications and the potential reduction of nutritional stress factors. Food Technol. 38(2): 120. UGC Approved Journal (Sr. No. 3430 Journal No. 62441) / NAAS Score 2017: 3.23, GIFactor: 0.9 29