African Journal of Agriculture and Food Security

African Journal of Agriculture and Food Security ISSN 2375-1177 Vol. 7 (9), pp. 001-007, September, 2019. © International Scholars Journals

Full Length Research Paper

Comparison of the degree of fermentation and fungal profiles of raw cocoa beans sourced from three Ivorian main producing regions

Tagro S. Guehi^1*, N’Dri D. Yao¹, Niamien P. Manizan², Koffi R. Nevry³, Louis B. Koffi ⁴ and Yao M. Konan³

¹Laboratoire de Biochimie et de Technologie Alimentaire. U.F.R-S.T.A, Université d’Abobo-Adjamé, 02 Bp 801 Abidjan 02 Côte d’Ivoire.

²Laboratoire d’Environnement et de Biologie Aquatique (LEBA). UFR-SGE Université d’Abobo- Adjamé, 02 Bp 801 Abidjan 02 Côte d’Ivoire.

³Laboratoire de Microbiologie et de Biologie Moléculaire. U.F.R-S.T.A, Université d’Abobo-Adjamé, 02 Bp 801 Abidjan 02 Côte d’Ivoire.

⁴Laboratoire de Biotechnologie et de Microbiologie. Programme Cacao. CNRA. 08 BP 33 Abidjan 08 - Côte d'Ivoire.

Accepted 22 April, 2019

Abstract

The degree of fermentation and incidence of contaminating fungi were determined in 90 raw cocoa bean samples. Excessive moisture content and low percentages of brown beans are recorded in cocoa samples from Soubré and Alépé, corresponding to maximum value of percentages of purple, mouldy and insect infested beans. Differences in mould counts were detected in cocoa beans according to the producing regions; cocoa from Alépé was most contaminated by moulds. Six fungi were commonly isolated that is, Absidia corymbifera, Rhizopus oryzae, Aspergillus tubingensis, Aspergillus tamarii, Aspergillus flavus and Penicillium chrysogenum. Nearly all of the fungi recovered can be considered as storage fungi. Studies of cocoa samples revealed that raw cocoa beans collected from Duékoué appeared to be of better quality than that from Alépé and Soubré.

Key words: Cocoa, fermentation, fungi, quality.

African Journal of Agriculture and Food Security ISSN 2375-1177 Vol. 7 (9), pp. 001-007, September, 2019. © International Scholars Journals

Full Length Research Paper

Extraction performances of polar and non-polar solvents on the physical and chemical indices of African breadfruit (Treculia africana) seed oil

Titus Ugochukwu Nwabueze^* and Kalu Sunday Okocha

Department of Food Science and Technology, Michael Okpara University of Agriculture, Umudike, P.M.B 7267 Umuahia, Abia State, Nigeria.

Accepted 10 May, 2019

Abstract

The physical and chemical indices of African breadfruit (Treculia Africana) seed oil extracted with polar (isopropanol, Hexane and butanol) and non polar (Acetone) solvents were investigated. The oil (19.85%) and energy contents 452.35 (Kcal) suggest that African breadfruit seeds are a high -energy food. The yields were significantly (P 0.05) different with hexane extracted (non-polar solvent) oil having 19.85 % whilst oil extracted with polar solvents ranged from 15.58 -19.30 %. Melting points were 34, 27, 26, 21 ⁰C for oil extracted with hexane, isopropanol, butanol and acetone respectively. Smoke points were within the limits of 170 – 255 ⁰C for the four oil samples. Iodine values ranged from 14.50 (hexane extracted) t0 25.17 (acetone extracted) . Saponification values ranged from 125.89-267.85 while peroxide values were 3.20 mg/kg (hexane) and 3.60-3.83 mg/kg for polar solvents. Free fatty (oleic) acid of oil extracted with hexane was 1.71% and polar solvent extraction ranged from 1.65- 1.78%. Hexane had the least peroxide value (8.74 mg/kg) compared to higher values for oil extracted with the polar solvents (9.10 - 9.83 mg/kg).

Keywords: African breadfruit, Treculia Africana, oil extraction, saponification, fatty acids, peroxide value, thiobarbituric acid

African Journal of Agriculture and Food Security ISSN 2375-1177 Vol. 7 (8), pp. 001-010, August, 2019. © International Scholars Journals

Full Length Research Paper

Some properties of starches from cocoyam (Colocasia esculenta) and cassava (Manihot esculenta Crantz.) grown in Malawi

Davies E. Mweta^1*, Maryke T. Labuschagne¹, Elizma Koen¹, Ibrahim R. M. Benesi² and John D. K. Saka³

¹University of the Free State, Department of Plant sciences, P. O. Box 339, Bloemfontein, 9300, South Africa.

²Chitedze Agricultural Research Station, P. O. Box 158, Lilongwe, Malawi.

³University of Malawi, Chancellor College, P. O. Box 280, Zomba, Malawi.

Accepted 05 May, 2019

Abstract

The physicochemical and functional properties of starch from cocoyam and ten varieties of cassava grown in Malawi were studied to unravel their potential in industrial application. The properties of starch varied significantly with crop and among varieties. Cocoyam starch granules exhibited polygonal truncated shapes and small sizes (average of 7 µm) while the cassava starch granules were rounded, irregular with oval and truncated ellipsoidal-granules with average size of 10.14 µm. The cocoyam starch gave lower values of amylose values content and paste clarity but higher phosphorus content, maximum wavelength of iodine complex absorption and blue value than cassava starches. Cassava starches gels were more stable to freeze thawing releasing 28.40 – 46.92% of the water than cocoyam which released 54.06% of its water. Swelling and solubility of both cocoyam and cassava starches increased with temperature (60 - 90°C) . Cocoyam starch exhibited lowered swelling power and solubility than cassava starches. The studies of gelatinization and retrogradation characteristics indicated similar enthalpy values of gelatinization of cocoyam and cassava starch; cocoyam starch displayed higher retrogradation tendencies than cassava starches.

Key words: Cocoyam, cassava, amylose, blue value, swelling, solubility, paste, freeze-thaw, gelatinization, retrogradation.

African Journal of Agriculture and Food Security ISSN 2375-1177 Vol. 7 (8), pp. 001-004, August, 2019. © International Scholars Journals

Full Length Research Paper

Effect of partially defatted soybeans or groundnut cake flours on proximate and sensory characteristics of kokoro

P. I. Uzor-Peters¹, N. U. Arisa^2*, C. O. Lawrence¹, N. S. Osondu¹, and A. Adelaja¹

¹Department of Food Technology, University of Ibadan, Ibadan, Nigeria

²Department of Food Technology, Bells University of Technology, Ota, Nigeria.

Accepted 15 April, 2019

Abstract

Kokoro a local maize snack was made from substitution of maize flour with either defatted soybean or groundnut cake flour (9:1, 7:3, 5:5, 3:7 and 1:9 substitution ratios) were evaluated for proximate and sensory qualities. Increase in substitution ratio produced kokoro with higher nutritional content (28.46 and 35.10 percent protein for those made from 1:9 substitution ratio respectively). Increase in substitution with the two substitutes progressively increased protein and fat content but reduced the ash, crude fibre and carbohydrate contents. More over the crispiness and over all acceptability of the kokoro decreased with increasing substitution. Products made from 9:1 substitution were well accepted and compared favourably with whole maize product.

Key words: Maize, soybeans, groundnuts, defatted, substitution, nutrition.

African Journal of Agriculture and Food Security ISSN 2375-1177 Vol. 7 (7), pp. 001-005, July, 2019. © International Scholars Journals

Full Length Research Paper

Evaluation of tigernut (Cyperus esculentus) -wheat composite flour and bread

Ade-Omowaye, B. I. O.*, Akinwande, B. A., Bolarinwa, I. F. and Adebiyi, A.O.

Department of Food Science and Engineering, Ladoke Akintola University of Technology, P. M. B. 4000, Ogbomoso, Oyo state. Nigeria.

Accepted 14 April, 2019

Abstract

Consumer interest in dietary fiber has continued to increase as more information about its potential impact on health has become available. Among the underutilized crops in Nigeria is tigernut which could find useful application in baking industry because of its high level of dietary fibre and other inherent properties. This study therefore aimed at widening tigernut utilization in the country. Substituted wheat flour (WF) with tigernut flour (TF) at varying proportions (100:0; 90:10; 80:20; 70:30; 60:40; 50:50) was evaluated for proximate composition and physico-chemical properties. Physico- chemical properties of dough as well as sensory and physical properties of the bread produced from the different flour samples were also evaluated. The proximate composition of the flour samples showed a reduction of about 14 to 38% in protein content but with a significant enhancement in the fibre content (167 to 967%) depending on the level of substitution. The fat and ash contents, as well as the pH of the flour samples increased with increase in the proportion of the tigernut. Dough with good viscoelastic properties and acceptable bread with qualities similar to 100% wheat bread was produced from 10% tigernut flour addition.

Key words: Wheat, tigernut, composite flour, bread, proximate composition.

African Journal of Agriculture and Food Security ISSN 2375-1177 Vol. 7 (7), pp. 001-004, July, 2019. © International Scholars Journals

Full Length Research Paper

Drawback of loop-mediated isothermal amplification

Wang Deguo¹, Huo Guicheng¹*, Wang Fugui², Li Yonggang¹ and Ren Daxi¹

¹Key Laboratory of Dairy Science, Ministry of Education of China, Northeast Agricultural University, Harbin150030, China.

²Gansu Animal Husbandry Engineering Vocational Technical College, China.

Accepted 14 April, 2019

Abstract

Loop-mediated isothermal amplification (LAMP) was a novel nucleic acid amplification method that amplified DNA with high specificity, efficiency and rapidity under isothermal conditions using a set of four specially designed primers and a DNA polymerase with strand displacement activity. In our research, LAMP was developed to detect foodborn Salmonella in raw milk, a set of six primers, two outer, two inner and two loop primers, were designed from Salmonella genomic DNA targeting invA. Temperature condition for detection of Salmonella was optimized to be 61°C. At the same time, LAMP was found to be effective when the template was pure; however, the usefulness of LAMP methods can be limited by the presence of inhibitors in the analysis of raw milk, unlike all the reports about LAMP, the sensitivity of LAMP was lower than that of PCR methods.

Key words: Loop-mediated Isothermal Amplification, LAMP, Foodborn Salmonella, raw milk, sensitivity.