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The cassava plant is grown in tropical and subtropical countries, which represents, alongside with its by-products, an important source of food and feed. Hence, this plant has the capacity to promote the economic development of those countries and provide food security. However, cassava has some disadvantages due to the antinutrient compounds produced in its tissues. In addition, the cassava roots have a low protein content. Due to the economic and practical advantages, the solid-state fermentation (SSF) has been used as a cost-effective and efficient processing method to detoxify the cassava products and enrich them in nutrients. This chapter reviews the solid-state fermentation technique of cassava products for the production of valuable components for food and feed applications, microorganisms involved in this process, and key factors used to optimize the SSF process.
Department of Chemical Engineering, Institut Teknologi Sepuluh Nopember (ITS), Surabaya, Indonesia
Tri Widjaja
Department of Chemical Engineering, Institut Teknologi Sepuluh Nopember (ITS), Surabaya, Indonesia
Setiyo Gunawan*
Department of Chemical Engineering, Institut Teknologi Sepuluh Nopember (ITS), Surabaya, Indonesia
*Address all correspondence to: gunawan@chem-eng.its.ac.id
1. Introduction
Cassava (Manihot esculenta Crantz) is grown in tropical and subtropical countries. It is a vital source of food and feed and it can promote economic development and provide food security [1]. Cassava production has been promoted globally by the International Fund for Agricultural Development (IFAD) and the United Nations Food and Agriculture Organization (FAO) to develop cassava strategies [2]. Reports indicate that production rates will reach 300 million tons per year by 2020 [3]. Due to its high drought tolerance, cassava plant cultivation can take place even under critical environmental conditions, with an ideal high yield of approximately 50% for leaves and 6% for roots at plant maturity [4]. Its peel may make up 10–20% of the roots’ wet weight [5]. However, cassava has some disadvantages; its tissues contain anti-nutritional compounds and very low protein content [6, 7].
Among all the antinutrients, hydrogen cyanide (HCN) is of great concern, the concentration of which is in cassava and its by-products are much higher than the World Health Organization (WHO) safe limit for human consumption (10 ppm) [8, 9]. Konzo is an irreversible neurological disease associated with intake of HCN [10]. Therefore, a detoxification process is needed to reduce anti-nutritional levels in order to consume cassava safely. Solid-state fermentation (SSF) has been used as an economical and efficient processing method for enriching and detoxifying cassava and its by-products [11, 12]. Various process parameters such as particle size, moisture content, water activity, pH, the inoculum size, incubation time, concentration of nutrient supplementation, and temperature can affect the microbial growth, enzyme production, and formation of the product during the SSF process [13].
This chapter discusses fermented cassava products through solid-state fermentation for food and feed applications, as well as microorganisms involved in solid-state fermentation and the essential processing variables used to optimize the process.
Fermentation has been one of the most used technologies to improve the taste and sensory properties of food and continues to be one of the most widely used methods of preserving the food for a length of time [14, 15]. The cassava fermentation process is a strategy to improve nutritional value by enriching protein and detoxifying toxic and anti-nutritional compounds, in particular by reducing toxic cyanogenic glycosides to a safe level of consumption in cassava products as well as reducing post-harvest losses [16, 17, 18].
There are two kinds of fermentation, i.e., spontaneous (natural) fermentation and controlled fermentation. For the natural fermentation, the conditions are selected so that to produce the most suitable microorganisms for the production of growth by-products characteristic of a particular type of fermentation [19]. The controlled fermentation is generally used when the natural fermentation is unstable or the bacteria are not able to grow. In this case, specific microbial strains, such as lactic acid bacteria (LAB), yeast, and fungal are isolated, characterized, and preserved for later use as starter cultures [20]. Under optimal growth conditions, these cultures can be used as single or combined starter cultures. As a result, the quality of products and their organoleptic characteristics are well controlled and predictable [20, 21].
However, the fermentation process can be broadly categorized into submerged fermentation (involving soaking in water) and solid-state fermentation (without soaking in water) [22]. The solid-state fermentation (SSF) technique has several advantages over submerged fermentation (SmF). However, the SSF has some constraints. Table 1 illustrates the advantages and disadvantages of SSF over SmF [23].
2.1 Solid-state fermentation and its application in cassava products
In recent years, the cassava population has developed numerous processing methods (soaking, boiling, drying, and fermentation) [24, 25, 26]. SSF is one of the promising processes of enriching protein and detoxifying of cassava products [27, 28, 29].
Fermented cassava products by SSF, such as flour, gari, starch, bread, and biomass contain high protein content that can either be consumed by humans or animals, replacing expensive, conventional protein sources in different parts of Latin America, Africa, and Asia [30]. The major fermented cassava products by SSF can be derived from different parts of the cassava plant, such as roots, peels, and leaves.
2.1.1 Cassava roots
Cassava is grown in many developing countries for its roots as a primary source of carbohydrates and ranks third in the developing countries as the leading source of energy in human diets along with rice and wheat [31]. World production of cassava is estimated at 277 million tons of fresh root in 2017 [32]. Cassava root has several advantages compared to other crop roots, including high productivity, resistance to droughts and pests, flexible harvesting age, and it can be kept in the ground until they are needed [33]. However, cassava root also has certain disadvantages; its tissues contain toxic compounds (a cyanogenic glycoside), low protein content (1% fresh root weight), and short shelf life of 1–3 days [34].
Food processing techniques have been used to convert cassava tubers into flour as an alternative way to preserve the roots after harvesting and then further use it for industrial and traditional purposes [35, 36]. Gari and flour are the most popular fermented food products from cassava roots by SSF. In West Africa, approximately 200 million people consume gari [37, 38]. Figure 1 shows the production of flour and gari under the solid-state fermentation [11].
Figure 1.
The production chart of cassava products (flour and gari) under SSF.
The purpose of cassava root fermentation is to increase the low protein content from 2% to about 7% or more than the critical crude protein content [39]. To achieve this goal, several solid-state fermentation techniques have been used. Raimbault et al. [40] reported the principle underlying the SSF procedure for the enrichment of cassava flour. This procedure led to the enrichment of crude protein from 1 to 18–20%, which improved between 1700 and 1900% after 30 h of fermentation. Oboh and Elusiyan [41] studied the effect of solid-state fermentation by R. oryzae and S. cerevisiae on the improvement of nutritional values of cassava flour produced from two different varieties of cassava root. The nutritional contents of cassava flour were assayed before and after 72 h of fermentation. This study has observed that S. cerevisiae was more effective than R. oryzae in the nutrient enrichment of cassava flour. The results of this study are presented in Figures 2–5. Essers et al. [42] investigated the effect of SSF on the degradation of hydrogen cyanide level in cassava root using six fungal strains, namely Rhizopus stolonifer, Rhizopus oryzae, Mucor racemosus, Bacillus sp. Geotrichum candidum, and Neurospora sitophila. The reduction in cyanide content was more than 60% after 72 h of fermentation.
Figure 2.
Proximate composition of the cassava flour obtained from cassava varieties of low HCN subjected to SSF.
Figure 3.
Proximate composition of the cassava flour obtained from cassava varieties of medium HCN subjected to SSF.
Figure 4.
Mineral contents of the cassava flour obtained from cassava varieties of low HCN subjected to SSF.
Figure 5.
Mineral contents of the cassava flour obtained from cassava varieties of medium HCN subjected to SSF.
In addition, Oboh and Akindahunsi [11] investigated the effect of solid-state fermentation with S. cerevisiae on the nutritional and antinutrient contents of cassava products (flour and gari). After 72 h of fermentation, the results revealed that the content of protein and fats in cassava flour increased by 10.9 and 4.5%, respectively. The protein and fat content of fermented gari also improved by 6.3% and 3.0%. In contrast, the content of cyanide in flour and gari decreased to 9.5 and 9.1 (mg/kg), respectively. However, the tannin content, crude fiber, and ash content of the cassava products did not change significantly under SSF.
2.1.2 Cassava peels
Cassava wastes, such as peels and leaves and starch residues make up 25% of the total cassava plant [43]. Cassava peel is the leading waste from the cassava plant, but its use is limited due to the high content of cyanide and fiber as well as low protein and therefore disposed of it after cassava processing into food or other industrial products [44, 45]. Many efforts have been made using SSF techniques to enrich the protein content and degrade the cyanide level of cassava peels for animal feed.
Bayitse et al. [12] studied protein enrichment of cassava residue using Trichoderma pseudokoningii under solid-state fermentation for 12 days, urea, and ammonium sulfate was used as a nitrogen source, and the moisture content ranged from 60 to 70%. The result showed an improvement in crude protein content of 12.5% using urea as a nitrogen source, and a moisture content of 70%, as compared to 8.89 and 6.37% improvement observed with ammonium sulfate as a nitrogen source, and without using nitrogen source. The study observed a decrease in cyanide content, but it did not attribute it to the fermentation effect of Trichoderma pseudokoningii, rather it stated that the reduction could have been as a result of the pre-processing of cassava peels.
Iyayi and Losel [43] also evaluated protein improvement of cassava peels using different types of microorganisms and fermentation time (Saccharomyces cerevisiae, Aspergillus niger, Rhizomucor miehei, and Mucor strictus). The solid-state fermentation of cassava peels by S. cerevisiae produced the highest protein content from 5.6 to 16.74% for 21 days. Also, they reported the maximum fermentation period for the protein enrichment of cassava peel to be from 12 to 15 days, after which no significant change was observed, which is in line with the work reported by Bayitse et al. [12].
Ezekiel and Aworh [13] evaluated the effectiveness of SSF with Trichoderma viride on the reduction of cyanide content and enrichment of the crude protein content of cassava peel by optimizing the fermentation conditions such as moisture content, pH, particle size, nitrogen source, and incubation temperature. The optimum SSF conditions were found at the initial moisture content of 60% (v/w), the particle size of 4.00 mm, a pH of 6.0, 30°C of temperature, and ammonium sulfate (10 g N/kg substrate) as nitrogen sources. After 8 days of fermentation, the cyanide content was reduced by 71% and improved the crude protein content from 4.2 to 10.43% at optimized conditions.
In another study by Ruqayyah et al. [45], the application of response surface methodology was used to optimize SSF conditions (moisture content, inoculum size, and pH) with P. tigrinus to enrich the crude protein content of cassava peel. A maximum protein content of 89.58 (mg/g) was obtained at 75% (v/w) moisture content, 7% (v/w) inoculum size, and pH of 5.3 with a fermentation time of 15 days. The optimum level resulted in a significant enrichment of the protein content by 55.16%.
Oboh [46] investigated the effect of solid-state fermentation of cassava peel with a mixture of Saccharomyces cerevisiae and two strains of lactic acid bacteria, Lactobacillus delbrueckii and Lactobacillus coryniformis to improve the nutritional value and detoxification of cassava peel. The chemical composition of cassava peel has been analyzed before and after fermentation. The results showed the effective performance of the SSF technique in removing cyanide by 86% after 7 days of fermentation. On the other hand, the mineral composition of the cassava peel did not change during the fermentation. The results of this study are presented in Table 2.
Relatively small scale, newly designed equipment is needed
The industrial level is available
Inoculation
Spore inoculation, batch process
Easy inoculation, continuous process
Contamination
Contamination risk of low-growth fungi
Contamination risk of single strain bacteria
Energy
Low consumption of energy
High consumption of energy
Equipment volumes
Low volumes and low equipment costs
High volumes and high equipment costs
Pollution (effluents)
No volumes of effluents
High volumes of effluents
Concentration/products
100/300 g/L
30–80 g/L
Table 1.
Comparative characteristics of solid-state and submerged fermentations.
Composition
Fresh
Naturally fermented
Fermented with a mixed culture
Crude protein (%)
8.2 ± 0.1
11.1 ± 0.3
21.5 ± 1.2
Crude fiber (%)
11.7 ± 0.5
6.5 ± 0.5
11.7 ± 0.5
Fat (%)
3.1 ± 0.4
3.5 ± 0.2
2.1 ± 0.1
Ash (%)
6.4 ± 0.4
6.0 ± 0.2
7.2 ± 0.2
Carbohydrate (%)
64.6 ± 0.2
67.3 ± 0.4
51.1 ± 0.4
Moisture (%)
5.1 ± 0.3
5.7 ± 0.2
6.4 ± 0.4
Ca (ppm)
0.03 ± 0.00
0.03 ± 0.00
0.03 ± 0.00
Na (ppm)
00.04 ± 0.00
0.04 ± 0.00
0.04 ± 0.00
Zn (ppm)
0.01 ± 0.00
0.01 ± 0.00
0.01 ± 0.00
K (ppm)
0.05 ± 0.00
0.05 ± 0.00
0.05 ± 0.00
HCN (mg/kg)
45 ± 0.3
24 ± 0.2
6.1 ± 0.4
Table 2.
The effect of fermentation on the chemical composition of cassava peels.
2.1.3 Cassava leaves
Cassava leaves are an extremely rich source of proteins, vitamins, and minerals that exceed some of the other green vegetables [47, 48]. The production of cassava leaves is estimated at 10 tons of dry leaves per hectare, which has a similar yield with the roots [49]. Cassava leaves are consumed in most Southeast Asian and African societies, such as Indonesia, Malaysia, Congo, Madagascar, and Nigeria [50, 51]. However, cassava leaves contain both nutritive (33.8–37.4% protein content) and anti-nutritional compounds [301.04–192.47 (mg/100 g) HCN content] [52]. Boiling, soaking, steaming, drying the sun, drying the oven, and cooking are the most common methods for processing cassava leaves in African and Asian countries [53].
The origin of HCN in the cassava leaves is a two-step process [54, 55]. First, the linamarin, a cyanogenic glycoside, which represent 93% of cyanogenic glycosides found in cassava (7% is lotaustralin), is hydrolyzed by linamarase (a beta-glycosidase) into glucose and cyanohydrin. Then, in the second step, the cyanohydrin is decomposed, either enzymatically or not, to HCN and acetone. The nonenzymatic pathway depends on pH. At pH > 6, the HCN is liberated, but at an acidic pH (~5), the process is much lower, and the resulting HCN is therefore relatively lower in concentration. However, this approach did not assure full hydrolysis of cyanogens. The partial breakdown of the leaf cells only partially releases linamarase resulting in only a certain proportion of the cyanogenic compounds being converted to HCN. This implies that a proportion of the cyanogens remain present in the leaves after processing and resulting in the release of HCN directly into the human body upon consumption.
The conventional methods have been proven to be ineffective for lowering the cyanide content in cassava leaves to the safe limit, at the same time causing a significant loss of protein and essential nutrients, which is highly desired from the cassava leaves [56, 57, 58, 59, 60]. Hence, the establishment of a universally acceptable method that produces edible leaves with low cyanide level while maintaining maximum nutritional content is challenging and still far away from being established. Among the efforts made so far, Morales et al. [61] proposed a solid-state fermentation of cassava leaves, reducing the cyanide content while improving the nutritional value of the processed leaves. SSF was performed using Rhizopus oligosporus, and babassu mesocarp flour was the substrate used, supplemented by cassava leaf flour. The solid-state fermentation decreased the total cyanide content of the cassava leaves by 94.18%, also SSF increased the quantity and quality of crude protein content by 15%, resulting in the relative nutritional value of 98.18% for food, which is equivalent to casein (100%). Furthermore, Kobawila et al. [62] investigated the effect of alkaline fermentation on the reduction of cyanide level in cassava leaves to produce ntoba mbod. The dominant microflora in the fermentation of the cassava leaves was Bacillus subtilis, Bacillus macerans, and Bacillus pumilus. These bacteria can utilize cyanide acid for their nutrition [63]. Thus, they are responsible for the reduction of the cyanide content in the medium of fermentation (~70% removal). However, the report did not provide the effect of the fermentation process on the protein content of cassava leaves.
One of the essential criteria for the solid-state fermentation is the selection of an appropriate microorganism [64]. Several research works have explored different types of microorganisms mainly fungi, yeasts, and bacteria, as well as different substrates to favor the metabolism of the microorganisms in SSF of cassava products. Examples of microorganisms associated with solid-state fermentation of cassava products for food and feed applications are summarized in Table 3.
The process control of the solid-state fermentation parameters is closely related to the metabolic regulation of microorganisms [74]. Based on the metabolic needs of the fermentation microorganisms, the control of water activity, oxygen content, temperature, and pH are the main solid-state fermentation parameters [23]. In the solid-state fermentation process, the water, gas, and heat caused by the growth microbes are the dominant factors that determine the environmental changes. The environmental factors can affect the microbial growth and formation of the product during the SSF process [75, 13]. Therefore, the physical-chemical parameters must be controlled.
3.1 Water activity and moisture content
The unique feature of solid-state fermentation is that there is almost no free water in the substrate [76]. However, microorganisms can grow depending upon the water activity of the substrate [64, 75]. The growth of fungi and some yeast usually requires a water activity value between 0.6 and 0.7 [77]. In addition to meet the microbial physiological requirements, the water content level plays a decisive role in the variation of the three-phase structure relating to water retention, permeability, and thermal conductivity. The degree of swelling in the SSF system was low at a lower moisture level and hence increased water stress reduces nutrient solubility. On the contrary, the higher level of humidity results in changes in substrates that reduce porosity, thus contributing to stickiness and reduced gas exchange [78, 79]. According to Grover et al. [80], the required moisture content should range between 60 and 80% for an efficient SSF system.
3.2 Temperature
The fermentation temperature affects microbial growth, spore germination, and the formation of product [81]. Heat generation in solid-state fermentation system is more problematic than in liquid fermentation. Due to poor heat conductivity and accumulation of metabolic heat in the material combined with substrate shrinkage and decreased porosity, gas convection is severely impeded. Previous studies showed that the significant resistance to heat transfer in solid-state fermentation was low conduction efficiency [82, 83].
Therefore, moisturizing is a common measure of temperature control. In addition, routine operations (e.g., forced ventilation and jacket cooling) all can solve these problems [84]. The evaporative cooling is one of the main solid-state fermentation temperature control measures [85, 86]. In general, the aeration could reduce the temperature gradient of the medium [23]. The forced ventilation can take away more than 80% of the heat generated from the substrate [84]. From the current investigation, it is difficult to maintain the temperature at an ideal range in SSF system. To reach this aim, the main strategy used in large-scale solid-state fermentation is to combine ventilation and humidity [77].
3.3 Oxygen concentration
The gas environment is a critical factor that significantly affects the relative levels of biomass and the production of an enzyme [23]. Oxygen uptake rate (OUR) and carbon dioxide production (CDPR) can be used to assess the state of the solid-state fermentation process. However, different microorganisms cause these assessments to vary. Ghildyal et al. [87] studied the impact of the gas concentration gradient on product yield in a tray solid-state fermentation bioreactor. The results showed that the variations of O2 and CO2 concentration gradients were visible, which severely affected product yield. The yield decreased when gradient increases. Gowthaman et al. [88] also studied the impact of gas concentration gradient on the product in a packing bed bioreactor. The results showed that the gas concentration gradient could be eliminated and the ability of mass transfer can be enhanced by forced ventilation, which increased enzyme activity.
3.4 pH value
In general, if the initial pH value of the medium is adjusted, the variations of pH value during the solid-state fermentation process need to be considered [89]. During the fermentation process, the pH values change drastically. The reason is that organic acids including citric and lactic are secreted during the fermentation process, which decreases the pH [23]. While the increase in pH was rationalized in terms of organic acid decomposition and protein degradation in the raw materials into amino acids and peptide fractions [90]. The pH values are difficult to determine by conventional detection in SSF due to the low water content of the substrate. Nitrogen-containing inorganic salts (such as urea) are often used as sources of nitrogen to offset the pH variation in the fermentation process [91, 92].
In the study conducted by Ezekiel and Aworh [13] to evaluate the effect of pH on protein enrichment and soluble sugars of cassava peel by Trichoderma viride, the fungus was grown in a controlled pH medium of 4.– 6.0 with an incubation time of 8 days. The optimal growth condition was observed at pH 6.0. The protein increased in cassava peels from 230 at pH 4.0 to 270 (mg/gm) at pH 6.0. Also, the sugars yield at pH 5.0 and 6.0 was five times higher compared to pH 4.0. According to the study, the growth rate of the fungi at pH below five was affected by high acidity, leading to reduced bio-conversion of sugars into protein.
The results discussed in this chapter highlighted the importance of the SSF technique applied to cassava to improve its nutritional value. The solid-state fermentation using microbial protein is beneficial for the reduction of cyanide contents while the content of protein and other nutrients is increased compared to those obtained by the conventional approaches, i.e., soaking, boiling, and drying. Thus, the SSF technique for processing cassava products is better suited for developing societies and rural communities in the African and Asian countries that do not have easy access to available protein sources.
The authors are thankful to the Ministry of Research, Technology and Higher Education of the Republic of Indonesia for its financial support to this project through the grant no. 849/PKS/ITS/2018.
1.FAO, IFAD. The global cassava development strategy and implementation plan. In: Proceedings of the FAO and IFAD Validation Forum on the Global Cassava Development Strategy; 26-28 April 2000; Rome. Rome: FAO and IFAD; 2001. pp. 13-15
2.Howeler RH. Endorsement of the global cassava development strategy. In: Proceedings of the FAO and IFAD Validation Forum on the Global Cassava Development Strategy; 26-28 April 2000; Rome. Rome: FAO and IFAD; 2001. p. 57
3.Agustian A. Bioenergy development in the agricultural sector: Potential and constraints of cassava bioenergy development. Analisis Kebijakan Pertonian. 2015;13(1):19-38
4.Tewe OO, Lutaladio N. Cassava for Livestock Feed in Sub-Saharan Africa. Rome: FAO; 2004. p. 64
6.Gunawan S, Widjaja T, Zullaikah S, Istianah N, Aparamarta HW, Prasetyoko D, et al. Effect of fermenting cassava with Lactobacillus plantarum, Saccharomyces cereviseae, and Rhizopus oryzae on the chemical composition of their flour. International Food Research Journal. 2015;22(3):1280-1287
7.Hawashi M, Ningsih TS, Cahyani SBT, Widjaja KT, Gunawan S. Optimization of the fermentation time and bacteria cell concentration in the starter culture for cyanide acid removal from wild cassava (Manihot glaziovii). MATEC Web of Conferences. 2018;156:01004. DOI: 10.1051/matecconf/201815601004
9.Hadiyat MA, Wahyudi RD. Integrating steepest ascent for the Taguchi experiment: A simulation study. International Journal of Technology. 2013;3:280-287. DOI: 10.14716/ijtech.v4i3.132
10.Bradbury JH. Simple wetting method to reduce cyanogen content of cassava flour. Journal of Food Composition and Analysis. 2006;19(4):388-393. DOI: 10.1016/J.JFCA.2005.04.012
11.Oboh G, Akindahunsi AA. Biochemical changes in cassava products (flour & gari) subjected to Saccharomyces cerevisae solid media fermentation. Food Chemistry. 2003;82(4):599-602. DOI: 10.1016/50308-8146(03)00016-5
12.Bayitse R, Hou X, Laryea G, Bjerre AB. Protein enrichment of cassava residue using Trichoderma pseudokoningii (ATCC 26801). AMB Express. 2015;5(1):80. DOI: 10.1186/s13568-015-0166-8
13.Ezekiel OO, Aworh OC. Solid state fermentation of cassava peel with Trichoderma viride (ATCC 36316) for protein enrichment. World Academy of Science, Engineering and Technology. 2013;7(3):6892-6991
14.Motarjemi Y. Impact of small scale fermentation technology on food safety in developing countries. International Journal of Food Microbiology. 2002;75(3):213-229. DOI: 10.1016/S0168-1605(01)00709-7
15.Smid EJ, Hugenholtz J. Functional genomics for food fermentation processes. Annual Review of Food Science and Technology. 2010;1:497-519. DOI: 10.1146/annurev.food.102308.124143
16.Caplice E, Fitzgerald GF. Food fermentations: Role of microorganisms in food production and preservation. International Journal of Food Microbiology. 1999;50(1-2):131-149. DOI: 10.1016/S0168-1605(99)00082-3
17.Kostinek M, Specht I, Edward VA, Schillinger U, Hertel C, Holzapfel WH, et al. Diversity and technological properties of predominant lactic acid bacteria from fermented cassava used for the preparation of Gari, a traditional African food. Systematic and Applied Microbiology. 2005;28(6):527-540. DOI: 10.1016/j.syapm.2005.03.001
18.Achi OK, Akomas NS. Comparative assessment of fermentation techniques in the processing of fufu, a traditional fermented cassava product. Pakistan Journal of Nutrition. 2006;5(3):224-229
19.Stiles ME, Holzapfel WH. Lactic acid bacteria of foods and their current taxonomy. International Journal of Food Microbiology. 1997;36(1):1-29. DOI: 10.1016/S0168-1605(96)01233-0
20.Zulu RM, Dillon VM, Owens JD. Munkoyo beverage, a traditional Zambian fermented maize gruel using Rhynchosia root as amylase source. International Journal of Food Microbiology. 1997;34(3):249-258. DOI: 10.1016/S0168-1605(96)01195-6
21.Oguntoyinbo FA, Cho GS, Trierweiler B, Kabisch J, Rösch N, Neve H, et al. Fermentation of African kale (Brassica carinata) using L. plantarum BFE 5092 and L. fermentum BFE 6620 starter strains. International Journal of Food Microbiology. 2016;238:103-112. DOI: 10.1016/j.ijfoodmicro.2016.08.030
22.Ray RC, Swain MR. Bio-ethanol, bioplastics and other fermented industrial products from cassava starch and flour. In: Colleen MP, editor. Cassava: Farming, Uses and Economic Impact. Hauppauge: Nova; 2011. pp. 1-32
23.Raimbault M. General and microbiological aspects of solid substrate fermentation. Electronic Journal of Biotechnology. 1998;1(3):26-27. DOI: 10.4067/S0717-34581998000300007
24.Nambisan B, Sundaresan S. Effect of processing on the cyanoglucoside content of cassava. Journal of the Science of Food and Agriculture. 1985;36(11):1197-1203. DOI: 10.1002/jsfa.2740361126
25.Bradbury JH, Denton IC. Rapid wetting method to reduce cyanogen content of cassava flour. Food Chemistry. 2010;121(2):591-594. DOI: 10.1016/j.foodchem.2009.12.053
26.Ezekiel OO, Aworh OC, Blaschek HP, Ezeji TC. Protein enrichment of cassava peel by submerged fermentation with Trichoderma viride (ATCC 36316). African Journal of Biotechnology. 2010;9(2):187-194. DOI: 10.5897/AJB09.620
27.Reade AE, Gregory KF. High-temperature production of protein-enriched feed from cassava by fungi. Applied and Environmental Microbiology. 1975;30(6):897-904
28.Vlavonou BM. Cassava processing technologies in Africa. In: Proceedings of the Interregional Experts’ Group Meeting on the Exchange of Technologies for Cassava Processing Equipment and Food Products; 13-19 April 1988; Ibadan, Nigeria. New York: UNICEF House; 1988. pp. 19-25
29.Akindahunsi AA, Oboh G, Oshodi AA. Effect of fermenting cassava with Rhizopus oryzae on the chemical composition of its flour and Gari products. Rivista Italiana delle Sostanze Grasse. 1999;76:437-440
30.Behera SS, Ray RC. Microbial linamarase in cassava fermentation. In: Ramesh RC, Christina MS, editors. Microbial Enzyme Technology in Food Applications. Boka Raton: CRC Press; 2017. pp. 337-346
31.Food and Agricultural Organization. Food Outlook: Global Market Analysis. Rome: FAO; 2009. pp. 23-27
32.Food and Agricultural Organization. Food Outlook: Biannual Report on Global Food Markets. Rome: FAO; 2018
33.Gunawan S, Istighfarah Z, Aparamarta HW, Syarifah F, Dwitasari I. Utilization of modified cassava flour and its by-products. In: Klein C, editor. Handbook on Cassava. New York: Nova Science Publisher; 2017. pp. 271-295
34.Westby A. Cassava utilization, storage and small-scale processing. In: Hillocks RJ, Thresh JM, Bellotti AC, editors. Cassava: Biology, Production and Utilization. New York: CABI Publishing; 2002. pp. 281-300
35.Defloor I, Nys M, Delcour JA. Wheat starch, cassava starch, and cassava flour impairment of the breadmaking potential of wheat flour. Cereal Chemistry. 1993;70(5):526-530
36.Dakwa S, Sakyi-Dawson E, Diako C, Annan NT, Amoa-Awua WK. Effect of boiling and roasting on the fermentation of soybeans into dawadawa (soy-dawadawa). International Journal of Food Microbiology. 2005;104(1):69-82. DOI: 10.1016/j.ijfoodmicro.2005.02.006
37.Yao AA, Dortu C, Egounlety M, Pinto C, Edward VA, Huch M, et al. Production of freeze-dried lactic acid bacteria starter culture for cassava fermentation into gari. African Journal of Biotechnology. 2009;8(19):4996-5004
38.Udoro EO, Kehinde AT, Olasunkanmi SG, Charles TA. Studies on the physicochemical, functional and sensory properties of gari processed from dried cassava chips. Journal of Food Processing & Technology. 2014;5(1):293. DOI: 10.4172/2157-7110.1000293
39.Aro SO. Improvement in the nutritive quality of cassava and its by-products through microbial fermentation. African Journal of Biotechnology. 2008;7(25):4789-4797. DOI: 10.5897/AJB08.1005
40.Raimbault M, Deschamps F, Meyer F, Senez JC. Direct protein enrichment of starchy products by fungal solid fermentation. In: Proceedings of the 5th International Conference on Global Impacts of Applied Microbiology; 21-26 November 1977. Bangkok; 1977
41.Oboh G, Elusiyan CA. Changes in the nutrient and anti-nutrient content of micro-fungi fermented cassava flour produced from low-and medium-cyanide variety of cassava tubers. African Journal of Biotechnology. 2007;6(18):2150-2157. DOI: 10.5897/AJB2007.000-2336
42.Essers AA, Jurgens CM, Nout MR. Contribution of selected fungi to the reduction of cyanogen levels during solid substrate fermentation of cassava. International Journal of Food Microbiology. 1995;26(2):251-257. DOI: 10.1016/0168-1605(94)00116-N
43.Iyayi EA, Losel DM. Protein enrichment of cassava by-products through solid state fermentation by fungi. Journal of Food Technology in Africa. 2001;6(4):116-118. DOI: 10.4314/jfta.v6i4.19301
44.Iyayi EA, Tewe OO. Effect of protein deficiency on utilization of cassava peel by growing pigs. In: Proceedings of the IITA/ILCA/University of Ibadan Workshop on the Potential Utilisation of Cassava as Livestock Feed in Africa; 14-18 November 1988. Ibadan: IITA; 1988. pp. 54-57
45.Ruqayyah TI, Jamal P, Alam MZ, Mirghani ME, Jaswir I, Ramli N. Application of response surface methodology for protein enrichment of cassava peel as animal feed by the white-rot fungus Panus tigrinus M609RQY. Food Hydrocolloids. 2014;42(15):298-303. DOI: 10.1016/j.foodhyd.2014.04.027
46.Oboh G. Nutrient enrichment of cassava peels using a mixed culture of Saccharomyces cerevisae and Lactobacillus spp solid media fermentation techniques. Electronic Journal of Biotechnology. 2006;9(1):46-49. DOI: 10.4067/S0717-34582006000100007
47.Montagnac JA, Davis CR, Tanumihardjo SA. Nutritional value of cassava for use as a staple food and recent advances for improvement. Comprehensive Reviews in Food Science and Food Safety. 2009;8(3):181-194. DOI: 10.1111/j.1541-4337.2009.00077.x
48.Wargiono J, Richana N, Hidajat A. Contribution of cassava leaves used as a vegetable to improved human nutrition in Indonesia. In: Proceedings of the Seventh Regional Workshop on Cassava Research and Development in Asia: Exploring New Opportunities for an Acient Crop; 28 October – 01 November 2002. Bangkok: CIAT; 2007. pp. 466-471
49.Morgan NK, Choct M. Cassava: Nutrient composition and nutritive value in poultry diets. Animal Nutrition. 2016;2(4):253-261. DOI: 10.1016/j.aninu.2016.08.010
50.Gidamis AB, O’Brien GM, Poulter NH. Cassava detoxification of traditional Tanzanian cassava foods. International Journal of Food Science and Technology. 1993;28(2):211-218. DOI: 10.1111/j.1365-2621.1993.tb01266.x
51.Balagopalan C. Cassava utilization in food, feed and industry. In: Hillocks RJ, Thresh JM, Bellotti AC, editors. Cassava: Biology, Production and Utilization. New York: CABI Publishing; 2002. pp. 301-318
52.Achidi AU, Ajayi OA, Maziya-Dixon BU, Bokanga M. The effect of processing on the nutrient content of cassava (Manihot esculenta Crantz) leaves. Journal of Food Processing & Preservation. 2008;32(3):486-502. DOI: 10.1111/j.1745-4549.2007.00165.x
53.Fasuyi AO. Nutrient composition and processing effects on cassava leaf (Manihot esculenta, Crantz) antinutrients. Pakistan Journal of Nutrition. 2005;4(1):37-42
54.Vetter J. Plant cyanogenic glycosides. Toxicon. 2000;38(1):11-36. DOI: 10.1016/S0041-0101(99)00128-2
55.Montagnac JA, Davis CR, Tanumihardjo SA. Processing techniques to reduce toxicity and antinutrients of cassava for use as a staple food. Comprehensive Reviews in Food Science and Food Safety. 2009;8(1):17-27. DOI: 10.1111/j.1541-4337.2008.00064.x
56.Padmaja G, Steinkraus KH. Cyanide detoxification in cassava for food and feed uses. Critical Reviews in Food Science and Nutrition. 1995;35(4):299-339. DOI: 10.1080/10408399509527703
57.Ngudi DD, Kuo YH, Lambein F. Amino acid profiles and protein quality of cooked cassava leaves or ‘saka-saka’. Journal of the Science of Food and Agriculture. 2003;83(6):529-534. DOI: 10.1002/jsfa.1373
58.Ngudi DD, Kuo YH, Lambein F. Cassava cyanogens and free amino acids in raw and cooked leaves. Food and Chemical Toxicology. 2003;41(8):1193-1197. DOI: 10.1016/S0278-6915(03)00111-X
59.Bradbury JH, Denton IC. Mild method for removal of cyanogens from cassava leaves with retention of vitamins and protein. Food Chemistry. 2014;1(158):417-420. DOI: 10.1016/j.foodchem.2014.02.132
60.Latif S, Müller J. Potential of cassava leaves in human nutrition: A review. Trends in Food Science and Technology. 2015;44(2):147-158. DOI: 10.1016/j.tifs.2015.04.006
61.Morales EM, Domingos RN, Angelis DF. Improvement of protein bioavailability by solid-state fermentation of babassu mesocarp flour and cassava leaves. Waste and Biomass Valorization. 2018;9(4):581-590. DOI: 10.1007/s12649-016-9759-y
62.Kobawila SC, Louembe D, Keleke S, Hounhouigan J, Gamba C. Reduction of the cyanide content during fermentation of cassava roots and leaves to produce bikedi and ntoba mbodi, two food products from Congo. African Journal of Biotechnology. 2005;4(7):689-696. DOI: 10.5897/AJB2005.000-3128
63.Knowles CJ. Microorganisms and cyanide. Bacteriological Reviews. 1976;40(3):652-680
64.Pandey A. Recent process developments in solid-state fermentation. Process Biochemistry. 1992;27(2):109-117. DOI: 10.1016/0032-9592(92)80017-W
65.Begum R, Rakshit SK, Rahman SM. Protein fortification and use of cassava flour for bread formulation. International Journal of Food Properties. 2011;14(1):185-198. DOI: 10.1080/10942910903160406
66.Jamal P, Tijani RI, Alam MZ, Mirghani ME. Effect of operational parameters on solid-state fermentation of cassava peel to an enriched animal feed. Journal of Applied Sciences. 2012;12(11):1166-1170. DOI: 10.3923/jas.2012.1166.1170
67.Purwadaria T. Solid substrate fermentation of cassava Peel for poultry feed ingredient. WARTAZOA. Indonesian Bulletin of Animal and Veterinary Sciences. 2013;23(1):15-22. DOI: 10.14334/wartazoa.v23i1.955
68.Thongkratok R, Khempaka S, Molee W. Protein enrichment of cassava pulp using microorganisms’ fermentation techniques for use as an alternative animal feedstuff. Journal of Animal and Veterinary Advances. 2010;9(22):2859-2862. DOI: 10.3923/javaa.2010.2859.2862
69.Phrueksawan P, Kulpreecha S, Sooksai S, Thongchul N. Direct fermentation of L (+)-lactic acid from cassava pulp by solid-state culture of Rhizopus oryzae. Bioprocess and Biosystems Engineering. 2012;35(8):1429-1436. DOI: 10.1007/s00449-012-0731-3
70.Roger DD, Jean-Justin EN, Francois-Xavier ET. Cassava solid-state fermentation with a starter culture of Lactobacillus plantarum and Rhizopus oryzae for cellulase production. African Journal of Microbiology Research. 2011;5(27):4866-4872. DOI: 10.5897/AJMR11.790
71.Essers AJ, Bennik MH, Nout MJ. Mechanisms of increased linamarin degradation during solid-substrate fermentation of cassava. World Journal of Microbiology and Biotechnology. 1995;11(3):266-270. DOI: 10.1007/BF00367096
72.Lateef A, Oloke JK, Kana EG, Oyeniyi SO, Onifade OR, Oyeleye AO, et al. Improving the quality of agro-wastes by solid-state fermentation: Enhanced antioxidant activities and nutritional qualities. World Journal of Microbiology and Biotechnology. 2008;24(10):2369-2374. DOI: 10.1007/s11274-008-9749-8
73.Azmi AS, Yusuf N, Jimat DN, Puad NI. Co-production of lactic acid and ethanol using Rhizopus Sp. from hydrolyzed inedible cassava starch and leaves. IIUM Engineering Journal. 2016;17(2):1-10. DOI: 10.31436/iiumej.v17i2.610
74.Chen HZ, Li ZH. Bioreactor engineering. Chinese Journal of Process Biotechnology. 1998;18:46-49
75.Nagel FJ. Process Control of Solid-State Fermentation: Simultaneous Control of Temperature and Moisture Content [Thesis]. Wageningen: Wageningen University; 2002
76.Pandey A. Solid-state fermentation. Biochemical Engineering Journal. 2003;13(2-3):81-84. DOI: 10.1016/S1369-703X(02)00121-3
77.Gervais P, Molin P. The role of water in solid-state fermentation. Biochemical Engineering Journal. 2003;13(2-3):85-101. DOI: 10.1016/S1369-703X(02)00122-5
78.Mahanta N, Gupta A, Khare SK. Production of protease and lipase by solvent tolerant Pseudomonas aeruginosa PseA in solid-state fermentation using Jatropha curcas seed cake as substrate. Bioresource Technology. 2008;99(6):1729-1735. DOI: 10.1016/j.biortech.2007.03.046
79.Mustafa SR, Husaini A, Hipolito CN, Hussain H, Suhaili N, Roslan HA. Application of response surface methodology for optimizing process parameters in the production of amylase by Aspergillus flavus NSH9 under solid state fermentation. Brazilian Archives of Biology and Technology. 2016;59. DOI: 10.1590/1678-4324-2016150632
80.Grover A, Maninder A, Sarao LK. Production of fungal amylase and cellulase enzymes via solid state fermentation using Aspergillus oryzae and Trichoderma reesei. International Journal of Advancements in Research & Technology. 2013;2(8):108-124
81.Lonsane BK, Ghildyal NP, Budiatman S, Ramakrishna SV. Engineering aspects of solid-state fermentation. Enzyme and Microbial Technology. 1985;7(6):258-265. DOI: 10.1016/0141-0229(85)90083-3
82.Saucedo-Castañeda G, Gutierrez-Rojas M, Bacquet G, Raimbault M, Viniegra-González G. Heat transfer simulation in solid substrate fermentation. Biotechnology and Bioengineering. 1990;35(8):802-808. DOI: 10.1002/bit.260350808
83.González-Blanco P, Saucedo-Castañeda G, Viniegra-González G. Protein enrichment of sugar cane by-products using solid-state cultures of Aspergillus terreus. Journal of Fermentation and Bioengineering. 1990;70(5):351-354. DOI: 10.1016/0922-338X(90)90150-U
84.Manpreet S, Sawraj S, Sachin D, Pankaj S, Banerjee UC. Influence of process parameters on the production of metabolites in solid-state fermentation. Malaysian Journal of Microbiology. 2005;1(2):1-9
85.Durand A, Arnous P, de Chardin OT, Chereau D, Boquien C. Protein enrichment of sugar beet pulp by solid-state fermentation. In: Ferranti MP, Fiechter A, editors. Production and Feeding of Single-Cell Protein. London: Applied Science Publisher; 1983. pp. 120-123
86.Grajek W. Cooling aspects of solid-state cultures of mesophilic and thermophilic fungi. Journal of Fermentation Technology. 1988;66(6):675-679. DOI: 10.1016/0385-6380(88)90072-6
87.Ghildyal NP, Gowthaman MK, Rao KR, Karanth NG. Interaction of transport resistances with biochemical reaction in packed-bed solid-state fermentors: Effect of temperature gradients. Enzyme and Microbial Technology. 1994;16(3):253-257. DOI: 10.1016/0141-0229(94)90051-5
88.Gowthaman MK, Ghildyal NP, Rao KR, Karanth NG. Interaction of transport resistances with biochemical reaction in packed bed solid state fermenters: The effect of gaseous concentration gradients. Journal of Chemical Technology and Biotechnology. 1993;56(3):233-239. DOI: 10.1002/jctb.280560303
89.Mitchell DA, Do DD, Greenfield PF, Doelle HW. A semi-mechanistic mathematical model for growth of Rhizopus oligosporus in a model solid-state fermentation system. Biotechnology and Bioengineering. 1991;38(4):353-362. DOI: 10.1002/bit.260380405
90.Awasthi MK, Pandey AK, Bundela PS, Khan J. Co-composting of organic fraction of municipal solid waste mixed with different bulking waste: Characterization of physicochemical parameters and microbial enzymatic dynamic. Bioresource Technology. 2015;182:200-207. DOI: 10.1016/j.biortech.2015.01.104
91.Raimbault M. Fermentation en milieu solid: Croissance de champignons filamentous sure substrate amylacé. Paris: ORSTOM; 1981. p. 291
92.Correia R, Magalhaes M, Macêdo G. Protein enrichment of pineapple waste with Saccharomyces cerevisiae by solid state bioprocessing. Journal of Scientific and Industrial Research. 2007;66(3):259-262
Written By
Mohamed Hawashi, Tri Widjaja and Setiyo Gunawan
Submitted: 13 March 2019Reviewed: 30 May 2019Published: 25 June 2019
Open access peer-reviewed chapter
