Effect of Fermentation by Rhizopus oligosporus or Amylomyces rouxii on In-Vitro Starch and Protein Digestibility of Decorticated Red Sorghum (Sorghum bicolor L. Moench)

Yudi Pranoto, Abdi Christia, - Sardjono


Solid substrate fermentation of cooked decorticated red sorghum was carried out by using mould Rhizopus oligosporus or Amylomyces rouxii. This study aims to investigate the growth of mould biomass by determining glucosamine and investigating the effects of fermentation on the changes in proximate composition, pH and total titratable acidity, and in-vitro starch and protein digestibility. Red sorghum was decorticated using a carborundrum discs to remove the bran. Decorticated sorghum was soaked in water (12 h for R. oligosporus and 1 h for A. rouxii fermentation), heated up to 90oC for 30 min, steamed for 30 min, and sterilized at 121oC for 20 min). Fifty g of sterile sorghum was inoculated with R. oligosporus (6.103 spore/g substrate) or A. rouxii spores (2.103 spore/g substrate) then incubated at 30oC. Samples were taken at 0, 12, 18, 24, 30, and 36 h for R. oligosporus fermentation and 0, 24, 48, 72, 120, and 168 h for A. rouxii fermentation. The results indicated that glucosamine content of fermented sorghum by R. oligosporus and A. rouxii were 4.49 and 11.72 mg/g dry matter at the end of fermentation, respectively. R. oligosporus hydrolyzed up to 11.4% of initial starch and 63.4% by. A. rouxii. There were more protein and fat losses in R. oligosporus fermentation than A. rouxii. Both fermentations produced acid and lowered pH to about 3.0, but pH went up to 4.0 at the end of R. oligosporus fermentation. Mould fermentation improved in-vitro starch digestibility, in A. rouxii it went up from 31.3% to 37.9% and down again to 11.4% at the end of fermentation. In R. oligosporus fermentation, it went up to 35.4%. In-vitro protein digestibility went up from about 35.0% to 37.0% and to 51.8% by R. oligosporus and A. rouxii fermentation, respectively.


red sorghum; fermentation; Rhizopus oligosporus; Amylomyces rouxii; starch digestibility; protein digestibility.

Full Text:



A.B. Obilana, Sorghum: Breeding and Agronomy. Encyclopedia of Grain Science. C. Wrigley, H. Corke, C. E. Walker, Eds. Edinburgh, Scotland: Elsevier Academic Press, 2004.

M.P. Sirappa, “Prospek pengembangan sorgum di Indonesia sebagai komoditas alternatif untuk pangan, pakan, dan industry”, Jurnal Litbang Pertanian, Vol. 22(4), pp. 133-140, 2003.

M.P. Oria, B. R. Hamaker, and J. M. Schull, “In vitro protein digestibility of developing and mature sorghum grain in relation to [alpha]-, [beta]-, and [gamma]- kafirin disulfide crosslinking”, Journal of Cereal Science, Vol. 22(1), pp. 85-93, 1995.

G.Y. Zhang and B. R. Hamaker, “Low alpha-amylase starch digestibility of cooked sorghum flours and the effect of protein”, Cereal Chemistry, Vol. 75(5), pp. 710–713, 1998.

K.G. Duodu, J. R. N. Taylor, P. S. Belton, and B. R. Hamaker, “Factors affecting sorghum protein digestibility”, Journal of Cereal Science, Vol. 38(2), pp. 117-131, 2003.

C.N. Day and R.O. Morawicki, “Effects of fermentation by yeast and amylolytic lactic acid bacteria on grain sorghum protein content and digestibility”, Journal of Food Quality, Vol.2018, pp. 1-8, 2018.

J.K. Mugula, “The nutritive quality of sorghum-commonbean tempe”, Plant Foods for Human Nutrition, Vol. 42(3), pp. 247-256, 1992.

K.A. Hachmeister, and D. Y. Fung, “Tempeh: a mold-modified indigenous fermented food made from soybeans and/or cereal grains”, Critical Reviews in Microbiology, Vol. 19(3), pp. 137-188, 1993.

J.K. Mugula, and M. Lyimo, “Evaluation of the nutritional quality and acceptability of sorghum-based tempe as potential weaning foods in Tanzania”, International Journal of Food Sciences and Nutrition, Vol. 51, pp. 269-277, 2000.

E.S. Murtini, A. G. Radite, and A. Sutrisno, “Characteristics of chemical content and disgestibility of brown sorghum tempeh”, Jurnal Teknologi dan Industri Pangan, Vol. XXII (2), pp. 150-155, 2011.

W.H. Holzapfel, “Appropriate starter culture technologies for small-scale fermentation in developing countries”, International Journal of Food Microbiology, Vol. 75(3), pp. 197-212, 2002.

A. Blandino, M. E. Al-Aseeri, S. S. Pandiella, D. Cantero, and C. Webb, “Cereal-based fermented foods and beverages”, Food Research International, Vol. 36, pp. 527-543, 2003.

H.L. Wang, E. W. Swain, and C. W. Hesseltine, “Glucoamylase of Amylomyces rouxii”, Journal of Food Science, Vol. 49(4), pp. 1210, 1984.

T.C. Cronk, K. H. Steinkraus, L. R. Hackler, and L. R. Maitick, “Indonesian tape ketan fermentation”, Applied and Environment Microbiology, Vol. 33(5), pp. 1067-1073, 1977.

U. Baumann, and B. Bisping, “Proteolysis during tempe fermentation”, Food Microbiology, Vol. 12, pp. 39-47, 1995.

K. R Kuswanto, Industrialization of Tempe Fermentation. Industrialization of Indigenous Fermented Foods. K. H. Steinkraus, Ed. New York, USA: Marcel Dekker, Inc., 2004.

K.E.B. Knudsen, A. W. Kirleis, B. O. Eggum, and L. Munck, “Carbohydrate composition and nutritional quality for rats of sorghum to prepared from decorticated white and whole grain red flour”, Journal of Nutrition, Vol. 118, pp. 588-597, 1988.

F.J. Bueso, R. D. Waniska, W. L. Rooney, and F. P. Bejosano, “Activity of antifungal proteins against mold in sorghum caryopses in the field”, Journal of Agricultural and Food Chemistry, Vol. 48(3), pp. 810-816, 2000.

A. Melake-Berhan, L. G. Butler, G. Ejeta, and A. Menkir, “Grain mold resistance and polyphenol accumulation in sorghum”, Journal of Agricultural and Food Chemistry, Vol. 44(8), pp. 2428-2434, 1996.

J.M. Awika, C. M. McDonough, and L. W. Rooney, “Decorticating sorghum to concentrate healthy phytochemicals”, Journal of Agricultural and Food Chemistry, Vol. 53(16), pp. 6230-6234, 2005.

R.G. Elkin, M. B. Freed, B. R. Hamaker, Y. Zhang, and C. M. Parsons, “Condensed tannins are only partially responsible for variations in nutrient digestibilities of sorghum grain cultivars”, Journal of Agricultural and Food Chemistry, Vol. 44(3), pp. 848-853, 1996.

Sardjono, “The growth kinetics of Aspergillus oryzae KKB4 on solid state culture system and the activity of crude extracellular enzyme on reducing Aflatoxin B”, Agritech, Vol. 28(4), pp. 145-149, 2008.

C. Desgranges, C. Vergoignan, M. Georges, and A. Durand, “Biomass estimation in solid state fermentation”, Applied Microbiology and Biotechnology, Vol. 35, pp. 200-205, 1991.

A. Zamani, A. Jeihanipour, L. Edebo, C. Niklasson, and M. J. Taherzadeh. “Determination of glucosamine and N-acetyl glucosamine in fungal cell walls”, Journal of Agricultural and Food Chemistry, Vol. 56, pp. 8314-8318, 2008.

AOAC, Official Methods of Analysis. Washington, D.C, USA: Association of Official Analytical Chemist, 1990.

M. Somogyi, “Notes on sugar determination”, Journal of Biological Chemistry, Vol. 195, pp. 19-23, 1951.

A. Nunes, I. Correia, A. D. Barros, and I. Delgadillo, “Sequential in vitro pepsin digestion of uncooked and cooked sorghum and maize samples”, Journal of Agricultural and Food Chemistry, Vol. 52, pp. 2052-2058, 2004.

K.G. Duodu, A. Nunes, I. Delgadillo, M. L. Parker, E. N. C. Mills, P. S. Belton, and J. R. N. Taylor, “Effect of grain structure and cooking on sorghum and maize in vitro protein digestibility”, Journal of Cereal Science, Vol. 35, pp. 161-174, 2002.

R.A. Sparringa, M. Kendall, A. Westby, and J. D. Owens, “Effects of temperature, pH, water activity and CO2 concentration on growth of Rhizopus oligosporus NRRL 2710”, Journal of Applied Microbiology, Vol. 92(2), pp. 329-337, 2002.

A. Abe, I.-N. Sujaya, T. Sone, K. Asano, and Y. Oda, “Microflora and selected metabolites of potato pulp fermented with an Indonesian starter ragi tape”, Food Technology and Biotechnology, Vol. 42(3), pp. 169-173, 2004.

K. Saito, A. Abe, I.N. Sujaya, T. Sone, and Y. Oda, “Comparison of Amylomyces rouxii and Rhizopus oryzae in lactic acid fermentation of potato pulp”, Food Science and Technology Resources, Vol.10(2), pp. 229-231, 2004.

A.E. Elkhalifa, O., R. Bernhardt, F. Bonomi, S. Iametti, M. A. Pagani, and M. Zardi, “Fermentation modifies protein/protein and protein/starch interactions in sorghum dough”, European Food Research and Technology, Vol. 222, pp. 559-564, 2006.

L.I. Ezeogu, K. G. Duodu, and J. R. N. Taylor, “Effects of endosperm texture and cooking conditions on the in vitro starch digestibility of sorghum and maize flours”, Journal of Cereal Science, Vol. 42(1), pp. 33-44, 2005.

X. Xu, In vitro Digestibility of Starch in Sorghum Differing in Endosperm Hardness and Flour Particle Size. Manhattan, USA: Kansas State University, Department of Grain Science, and Industry, 2008.

DOI: http://dx.doi.org/10.18517/ijaseit.10.6.12056


  • There are currently no refbacks.

Published by INSIGHT - Indonesian Society for Knowledge and Human Development