Rice Parboiling Practices and Technologies in Kano State

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59

RICE PARBOILING PRACTICES AND TECHNOLOGIES IN KANO STATE

Bello, M. M.1*, Abubakar, M. S.2, Lawan, I.2

1Centre for Dryland Agriculture, Bayero University, Kano, Nigeria 2Department of Agricultural Engineering, Bayero University, Kano, Nigeria * Corresponding Author: [email protected], +2348038872599

ABSTRACT

Paddy parboiling is an important aspect of rice processing which determines, to a large extent, the quality of milled rice. Although large amount of paddy is produced and processed in Nigeria, the country is still one of the leading importers of rice, with the imported rice being patronized more. This is due to the better quality of the imported rice. Therefore this study was conducted to assess the parboiling practices in Kano State, and to identify constrains hindering the local parboiling technology. A structured questionnaire and field study were used to evaluate the process as used in the rice clusters in the State (Kura,Karfi,Garko,Chiromawa,Kwanar Dawaki, and Tudun Wada). Information sought from the rice processors and other relevant organizations in the Study Area include; method of parboiling, equipment used, cost of parboiling, variety of paddy used, parboiling capacity and challenges of the parboiling activity. The survey revealed that parboiling is mostly done manually, using the soaking temperature range of between 55 0C to 700C and soaking time range of 9 to 17 hours. Aluminum and drum pots are predominantly used for the parboiling activity. Lack of modern parboiling technologies and poor understanding of the process of parboiling are the major constrains faced by the processors. With the large volume of paddy being produced and the involvement of many local people, particularly women in the parboiling industry, potentials exist once appropriate technologies are provided. This will result in having rice of better quality which may compete with the imported rice, as well as improving the livelihood of the local people.

Keywords: Parboiling; Rice Quality; Parboiling Technologies; Prospects and Challenges; Livelihood

1. INTRODUCTION

Rice serves as the staple food to more than half of overnight and then dried in the sun. The apparent world’s population and about half of the world benefit was that the rice hulls would split open paddy is parboiled (Miah et al., 2002). Parboiling and thus easily removed from the rice kernel. In is a hydrothermal treatment that is given to paddy recent times, parboiling involves soaking the prior to milling stage. The main objective of paddy in hot water, which reduces soaking time, parboiling is to gelatinize the starch (Das et al., and subsequent steaming of the soaked paddy 2004) which improves some properties of the rice before drying it. It has been established that and makes it easier for dehusking. Parboiling parboiling improves the milling quality of rough originates from India many years ago and its rice. Kernel defects such as cracks, chalkiness and primary purpose was to ease the removal of the immaturity are completely eliminated on husk (Kratochvil et al., 1992). In those days, parboiling (Farouk and Islam, 1995). Rice bran parboiling involves soaking the paddy in warm layers are rich in proteins, fibers, vitamins, and water overnight and then removing the husk in fats (Paiva et al., 2015) which migrate into the the morning. Velupillai et al., (1989) reported that endosperm of the rice during parboiling (Farouk in the early history of parboiling, the rough and Islam, 1995). Physical as well as chemical (paddy) rice was simply soaked in warm water modifications occurred in the grain, leading to www.bayerojet.com 52

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59 favorable changes such as easier shelling, higher Despite the huge amount of paddy produce in head rice yield, fewer broken grains, increased Nigeria, it’s still one of the leading importers of resistance to insects, better retention of nutrients parboiled rice. This is as a result of poor qualities and higher oil content in the bran (Igathinathene of the locally parboiled rice which makes the et al., 2005). Therefore, milling paddy without local population prefer the better quality imported parboiling results in rice that is devoid of these ones. This has a negative impact on the country’s nutrients (Paiva et al., 2014). These desirable economy and the livelihood of the local farmers. qualities of parboiled rice make it a highly Thus, this study was undertaken to identify the demand product worldwide, particularly in challenges and prospects of parboiling countries such as Nigeria, India, Italy, Turkey, technologies in Kano State, one of the leading USA and Bangladesh (Patindol et al., 2008). producers of rice in Nigeria

2. METHODOLOGY

2.1. Study Area questionnaires administered to them, thus a total Kano State is one of the 36 states of Nigeria, a of 300 questionnaires were administered and country in sub-Saharan Africa, which lies retrieved. The sample of the questionnaire used is between longitude 90 30’ and 12 0 30’ North and attached in the appendix. The questionnaire was 0 0 clear, succinct and unambiguous. Information latitude 9 30’ and 8 42’ East. The state is one of related to the method of parboiling, equipment, the most important rice producing areas of the costs, variety of paddy used, parboiling capacity country. This is largely due to the availability of and challenges of the parboiling method and more than 22,000 ha of irrigated schemes of the equipment used, etc were solicited in the HadejiaJama’are River basin Development questionnaire. Based on the responses, field study Authority, the vast Fadama areas that were further was further conducted to evaluate the process of developed under the erstwhile National Fadama parboiling and the equipment use by the farmers. Information was also sought from the Ministry of Development Project and the upland production Agriculture and other relevant organizations. area of Tudun Wada and Rogo towns (PrOpCom, These were analysed together with the 2007a). More than 20,000 farmers are involved in questionnaires’ responses and the field rice production, which is later processed and sold observations. Pertinent literatures were also in the Kano markets that serve a population of reviewed. over 9,000,000 people (PrOpCom, 2007b). Preliminary study conducted revealed that the 2.3 Instrumentation Rice Cluster Areas within the State includes; The instruments that were used includes; Kura, Karfi, Garko, Chiromawa, Kwanar Dawaki electrical weighing balance and ordinary and Tudun Wada. Thus, these Areas were used weighing balance for measuring weight of the for the study. paddy, calibrated plastic bucket for measuring volumes, grain moisture meter for measuring 2.2. Field Survey moisture content, stop watch for measuring time, 50 respondents were selected at random each mercury in glass thermometer for measuring from the aforementioned locations and temperature and digital camera.

www.bayerojet.com 53

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59

3. RESULTS AND DISCUSSION

3.1. Parboiling Methods an improved parboiling technology. Table 1 Majority of the respondents use traditional below shows the distribution of the respondents method of parboiling paddy. Only a fraction of in respect of the method of parboiling. the respondents adopt what they described as Table 1: Distribution of parboiling method used Method Frequency Percentage (%)

Traditional 297 99 Improved 03 1 Total 300 100

From the table above, it can be seen that the average mean of 61.3 oC and standard deviation traditional method of parboiling is the one of 4.95oC, and the duration of the soaking is mostly adopted in the study area with 99% of within the range of 9 – 17 hours from the the respondents using it, whilst only 1% of the observation of different sites in the area. The respondents are using an improved method. average total soaking time is 13.35 hours with This agrees with the findings established by standard deviation of 2.33 hours. This variation PrOpCom (2007b) which revealed that may be due to the difference in parboiling majority of the processors in Kano rice clusters equipment which have different conductivity. used the traditional method of parboiling. This soaking time is rather too long, as hot soaking was developed to reduce the 3.1.1 Traditional rice parboiling method processing time. For example, Bello et al. used by respondents The steps involved in the (2006) used a soaking time of 5 to 10 minutes traditional parboiling method as done in the with temperatures of 85 to 90 0 C in their study area are; soaking, steaming and drying. investigation of the optimum conditions for Figure 1 below shows the flowchart for paddy parboiling. The long duration of soaking parboiling one bag (75 kg) of paddy in the is adopted where cold water is normally used. study area. The flowchart depicts the basic unit With hot water, soaking time should be shorter operations of parboiling and the quantity of which will reduce the overall process time. water used in the parboiling. This traditional method is time consuming and laborious as Steaming This is the process where the paddy most of the processors can only parboiled is exposed to steam at a high temperature for between 1 to 3 bags of paddy per day. the paddy to reach gelatinization state. The steaming time is the duration in which the Soaking In this process, the paddy is immersed paddy is subjected to steam after soaking, for in water and heated for some hours. The heat gelatinization to take place. The steaming sources would then be withdrawn and the temperature use by the respondents varies mixture of parboiled paddy and water is left for between the range of 900C to 1000C with an some time before draining some of the water. average mean steaming temperature of 96.70C The soaking temperature refers to average and standard deviation of 4.985 and the temperature attained by the water. The total duration of steaming ranges from 45 min to 65 soaking time is the duration from the onset of min with the average mean of 56.2 min and heat application to the time by which water is standard deviation of 6.194 min. This drained, before steaming. The soaking temperature is unnecessarily high as starch temperature ranges from 50 - 70 oC with an gelatinization can be achieved at lower www.bayerojet.com 54

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59 temperatures, the range of gelatinization for of paddy which may affect the milling world rice being 55 to 75 oC (Bello et al. 2006). qualities. This result in waste of energy and over-cooking

Drying Drying is a critical part in parboiling in the paddy grain which results in breakage of activities. Drying in the study area is generally rice during milling. Also, the drying process done using open sun drying. The parboiled using this method is difficult during raining paddy is spread on the floor, tarpaulin sack or season poses another problem of open air mat and exposed to direct solar radiation as drying by increasing the process time. Almost shown in Plate 1. This process may be 100% of the respondents are using the responsible for the formation of internal stress traditional method of drying.

Plate 1: Traditional Drying Method

The amount of moisture of the paddy after higher moisture content wants to avoid high drying varies amongst the respondents within level of breakage while milling. This reason the study area. From data obtained, it was reported by the respondents is agreeing with discovered that the moisture content of paddy the findings of Bhattacharya and Indudhara, after drying is in the range of 11% to 17% wb, (1967) which showed that the cracks and with an average of 14.3% wb and standard fissures begin to appear when the moisture deviation of 1.825% wb. The respondents content of paddy falls below 18% wb. revealed that those that leave the paddy with

www.bayerojet.com 55

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59

Figure 1: Flow Chart for parboiling 1 bag of paddy

3.2. Parboiling Equipment Used in the Study prices of these parboilers are 1,500 Naira and 2, Area 500 Naira respectively. The respondents The survey revealed that 98% of the claimed that the main reason why they are respondents are using aluminum pot parboiler using this aluminum pot parboiler is because of and only 2% of the respondents are using a its good heat conductivity which minimizes the drum parboiler. The aluminum pot parboilers energy source used. The drum pot parboiler are made of aluminum plate and exist in (Plate 3) is made from a typical cylindrical various volumes ranging from one that can drum. It’s a normal drum with an opened top; consume 1 bag of paddy (75kg) to that which only 2% of the respondents are using it. The can consume 2 bags of paddy (150kg) per cycle drum pot parboilers require more energy, respectively. The typical aluminium pot according to the processors. This may be due to parboiler is shown in plate 2. The average its thickness. thickness of each is 8mm. The corresponding

Plate 2: Aluminium Pot Parboiler www.bayerojet.com 56

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59

Plate 3 : Drum Parboiler

3.3 Quality of Kano Parboiled Rice 3.5 Assistance from Governmental and Non Governmental Organizations It was observed that in the study area, the The respondents revealed that a lot of parboiled rice has poor qualities such as dark investigative studies were carried out with colour, broken head and chalkiness. These regards to the parboiling activity in the study qualities are attributed to lack of efficient area, but there were no any kind of assistance parboiling technologies and poor understanding provided to these processors in the Study Area. of the parboiling process. The consequence of Thus, the processors were left with their crude this is that local rice is rejected in preference to and traditional methods of parboiling paddy. the better qualities imported ones. The method predominantly used involved a lot 3.4 Cost of Parboiling of drudgery, untimeliness and inefficient. The variable costs incurred in paddy parboiling Therefore, the parboiling activity was found to activities include cost of paddy rice, cost of be helpless both from governmental and non- labour, cost of energy sources and cost of water governmental organizations in Study Area. used. The cost of the paddy varies with the variety. Jamila is the most expensive variety 3.6 Prospects and Challenges of Parboiling which cost about 6, 500 Naira per bag (75 kg), There are many challenges facing the while Dukusa variety which cost about 5,500 parboiling industry in Kano State. The two Naira per bag. Other varieties cost between 4, major problems are the absence of modern 900 to 5, 000 Naira per bag. The total cost of parboiling technologies and poor understanding labour was found to be about 70 Naira per bag. of the parboiling process by the local The majority of the respondents (90%) are processors. The local processors used using straw of sorghum, millet and paddy husk aluminum pots or drums for soaking and as their sources of energy. Two rolls of straw steaming. The aluminum pots used required are usually used to parboil one bag of paddy high amount of water for a successful steaming (75kg) which cost 200 Naira. All the and this causes the paddy at the bottom to end respondents claimed to be using 80 liters of up partially cooked while the one at the top is water for parboiling one bag of paddy (75kg) poorly parboiled. As a result, the paddy which cost 60 Naira. Based on these findings, becomes dark after milling, this affect the the total cost of parboiling 75 kg of paddy is quality of the rice. Also, the respondents approximately 330 Naira. claimed to be having difficulties in draining of www.bayerojet.com 57

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59 water after the activity, unlike with the producers of parboiled rice in the country. With improved parboiler that has control tap attached a lot of people involved in the parboiling to it at the bottom of the pot which makes the industries, albeit at small-scale level, there draining very easy. Also, because opened already exists a large market for the products containers are used for parboiling, there is a lot especially when quality is improved. of inefficiency in the energy utilized. The use Fortunately, the Nigerian government has of firewood and other agricultural biomass as recently turned its attention to value chain sources of energy is a source of concern addition and policies are being made that especially in the face of climate change. The would help the local farmers upgrade their drying is a critical unit operation in parboiling production level and technology. Once modern and it is generally done using open sun parboiling technologies are available and dryingin the study area. The steamed paddy is capacity of local processors is upgraded, the spread on the floor, tarpaulin sack or mat and qualities of local parboiled rice would improve, exposed to direct solar radiation. This is thereby making it more acceptable to the reported to cause internal stress in the paddy population. It’s pertinent to point out that the grain, which result to breakage of rice during local people are ready to patronize the local milling. The drying process during raining product provided it can give as much qualities season is also difficult as there is less sunshine. as the imported one. This would result in poverty reduction and improvement of Nigeria is one of the countries with high livelihood of the local farmers as well as demand of parboiled rice (Otegbayo, et. al., contribute to the country’s GDP. 2001) and Kano State is one of the leading

4.0 CONCLUSION

Paddy parboiling remains problematic in parboiling process hinder the local parboiling Nigeria despite its well establishment in many industry. Thus, there is need for improved countries. The locally parboiled rice in the technologies of parboiling in the area. The Study Area was found to have poor qualities. presence of huge market for parboiled rice and That is the possible reason why the local rice is the recent interest of the Nigerian Government rejected in preference to the better qualities to transform agricultural production signify imported ones. Lack of modern parboiling potentials in the local parboiling industry technologies and poor understanding of

REFERENCE Bello, M., Baeza, R. and Tolaba, M. P. (2006). issues/1967/Documents/Chem44_592.pdf on Quality Characterization Milled and Cooked 04/01/2014 @ 21:30 Rice Affected by Hydrothermal Treatment. Journal of Food Engineering. 72, pp. 124-133. Das, I., Das, S.K. & Bal, S., 2004. Specific Energy and Quality Aspects of Infrared (IR) Bhattacharya, K. R. and Swamy Induhara Y. M. Dried Parboiled Rice. Journal of Food (1967). Conditions of Drying Parboiled Paddy Engineering, 62, pp. 9 – 14. for Optimum Milling Quality. Contribution from Central Food Technological Research Farouk, S. M. and M. N. Islam (1995). Effects Institute, Mysore, India. Paper IV in series: of Parboiling and Milling Parameters on Processing and Quality Factors in Parboiling of Breakage of Rice Grain. Agricultural Rice, Accessed from http://www.aaccnet.org Mechanization in Asia, African, and Latin publications/cc/back America. 26(4): 33 – 34. www.bayerojet.com 58

ISSN : 1597-5835 Bello et al. (JET) Journal of Engineering and Technology Vol. 10 (2) 2015 ,52-59

V.Z., Wood, D., Williams, T., James P.J., and Igathinathane, C., P.K. Chattopadhyay, and Elias, M.C. (2015). Polishing and Parboiling L.O. Pordesimo (2005). Combination Soaking Effect on the Nutritional and Technological Procedure for Rough Rice Parboiling. Properties of Pigmented Rice Subjected to Transaction of the American Society of Different Degrees of Milling. Journal of Food Agricultural and Biological Engineers. ISSN Composition and Analysis, 35(1): 10 – 17 0001 – 2351, 48(2): 665 – 671. doi:10.1016/j.jfca.2014.05.003

Kaddus Miah, M. A, Haque, A., Douglass, M.P. Patindol, J., Newton, J. and Wang, Y.J. (2008). and Clarke B. (2002). Parboiling of Rice. Part Functional Properties as Effected by II: Effect of Hot Soaking Time on the Degree Laboratory Scale Parboiling of Rough Rice and of Starch Gelatinization. International Journal Brown Rice. Food Engineering and Physical of Food Science and Technology. 37:539 – 545. Properties. 73(8): 370 – 377. Kratochvil, C.P., Y.H.E., Lin and T.J. Novak (1994). Parboiled Rice Product and Method of PROPCOM (2007a). Financial Report on the Making Same. United State Patent 5316783. Baseline Survey of the Kano Rice Value Chain. Funded by the UK’s Departmental for Otegbayo B.O., Osamuel F., Fashain JB. International Development (DFID) (2001). Effect of Parboiling on Physico – chemical Qualities of Two Local Rice Varieties PROPCOM (2007b). Political Process Study of in Nigeria. Journal of Food Technology Africa. the Kano Rice Wholesale and Retail Market. 6:130 – 2. (Monograph Series# 11). Funded by the UK’s Department for International Development Paiva, F.F., Vanier, N. L., Berrios, J.D.J., Pinto, (DFI)