1,720,972 research outputs found
Optimisation of Ontaku/ Oshikundu: Pearl millet and sorghum malts quality and convinient premix development
No full textA research dissertation submitted in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in Science (Biochemistry)Oshikundu/Ontaku is a nonalcoholic, acidic, opaque fermented beverage. It is comprised of pearl millet (Pennisetum glaucum (L.) R. Br) meal/flour, commonly known as mahangu, malts of pearl millet or sorghum (Sorghum bicolour (L.) Moench) and/or brans (pearl millet). Brewing of oshikundu remains an art in households with no empirical improvement of a controlled fermentation flow process to give a consistent product. Some of the major limitations to the formal commercialisation of this brew are the absence of standardised malting process that gives a consistent malt quality and microbial safety. The lack of standard ingredient ratios (flour/meal: malt: water) of brewing. Also, the sedimentation of adjunct particles at the bottom (dreg), thus creating the difference in viscosity of oshikundu. Well-defined fermenting microorganisms are not used, and the preparation method still relays on a laborious time-consuming process. Therefore, this study investigated conditions for malting, reduction of dreg, identification of fermenting microorganisms and formulation of ingredient ratio for an improved preparation process. Grains used in the study were collected from Omahenene Agricultural Research Station (2015 harvest), of the Ministry of Agriculture, Water and Forestry. Pearl millet varieties Okashana 2 (SDMV 93032), Kantana (landrace) and Kangara (SDMV 92040), while sorghum varieties are Macia (SDS3220) and landrace commonly referred to as red sorghum. Malts of the two cereals were prepared by steeping in static water at 20-22oC for 2 hours wet and 2 hours air-rest for a total of 8 hours and germinated at 30oC. Malts were dried between 50-55oC for 24 hours. Cereals germinative energy was above 90% as recommended for sorghum by the European Brewery Convention. Malting loss was high up to 30% in pearl millet varieties and Macia. Crude protein and fibre were found to increase following malting. Reducing sugars were not detected in nongerminated pearl millet grains. Malts reducing sugars were statistically significant (p ≤ 0.05) between cereals. The malt reducing sugars was as follows Macia> Red sorghum> Kantana>Okashana 2 = Kangara. Malting resulted in significantly increased free amino nitrogen (FAN) content. Kantana had the highest FAN followed by Macia malt. No amylolytic activity was detected in nongerminated grains irrespective of the cereal. Pearl millet was found not to contain condensed tannins. Malts had an unacceptable high aerobic plate count load above 6.3 Log cfu/g or (2 × 107 cfu/g) as specified for Southern African sorghum malts. However, results show that the malts were not contaminated by Salmonella spp., Shigella and coliforms. Regulated mycotoxins in malts were found to be below the legal limits. Cereal malts are not of safety concern from coliforms and mycotoxins under these malting conditions. Oshikundu is likely fermented by lactic acid bacteria (Lactobacillus. plantarum, L. pentosus, L. acidifarinae, L. paraplantarum, L. spicheri, L. namurensis, L. zymae, L. fermentum, L. brevis, L. delbrueckii subsp bulgaricus, L. buncheri, Leuconostoc gurlium and Pediococcus acidilactici) and yeast (Saccharomyces cerevisiae and S. paradoxus). However, the dynamics of LAB and yeast during fermentation are not known. The use of smaller amounts of dry ingredients and pre-gelatinisation of pearl millet meal in the process of making oshikundu significantly decreases total solids. This suggests that the amount of suspended particles in oshikundu that tend to settle during storage can also be reduced through this route, in the absence of consumer acceptability test. The study demonstrated a creative formulation of a dry powder premix for brewing oshikundu. Preliminary sensory evaluation showed that panellists extremely liked the ease of preparation method, where only water was required to be added to the premix. The study demonstrated that malting pearl millet and sorghum grains under set conditions gave malts of acceptable quality (reducing sugars, free amino nitrogen, alpha and beta amylase activity, phenolic content, radical scavenging activity, mycotoxins and microbial load). Also, a lower amount of pre-gelatinised adjunct can be used to achieve the same yield of oshikundu and at the same time reduce dregs. Also, ingredient ratios were formulated by the use of dry ingredients premix for making oshikundu that was easy to prepare
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Physicochemical, nutrient and microbiological analysis of Oshikundu; a cereal based fermented beverage from Namibia.
No full textA thesis submitted in fulfilment of the requirements for the Degree of Master of Science.The aim of this study was to determine the physicochemical, nutrients, predominant microflora mainly looking at lactic acid bacteria and spoilage bacteria in Oshikundu samples collected from Omusati, Oshana, Ohangwena and Oshikoto regions. Oshikundu is brewed from pearl millet (Pennisetum glaucum L. R.Br.,) meal locally known as Mahangu, malted sorghum (Sorghum bicolor L. Moench), bran and water. Oshikundu pH ranged between 3.33 ± 0.127 in Oshana region and 3.60 ± 0.014 in Oshikoto region. Titratable acidity as lactic acid was found to be ranged between 1.20 % in Oshikoto and 1.68 % in Ohangwena region. Meanwhile acetic acid ranged between 0.10 % in Omusati and 0.30 % in Ohangwena region. The protein content ranged between 0.133 ± 0.007 and 0.178 ± 0.02 (mg/mL), insoluble fibre, 0.025 ± 0.01 % and 0.028 ± 0.004 %, energy, 46.8 ± 8.45 and 54.4 ± 4.17 (kJ/100 mL) on dry basis. Micro-nutrients including vitamin B1 and B2, were detected in Oshikundu. Minerals were analysed and revealed the presence of B, Ca, Cu, Fe, K, Mg, Mn, Na, S, Zn and P which was the highest (ranged between 3.914 ± 0.452 and 11.511 ± 7.264 ppm). The microflora of Oshikundu included 6 predominant Lactic acid bacteria (LAB): Lactobacillus plantarum, Lactococcus lactis ssp. lactis, Lactobacillus delbrueckii ssp. delbrueckii, Lactobacillus fermentum, Lactobacillus pentosus and Lactobacillus curvatus ssp. curvatus. Five bacterial species were identified that are likely to be responsible for Oshikundu spoilage; Enterobacter cloacae, Enterobacter sakazakii, Pseudomonas luteola, Pseudomonas aeruginosa and Serratia ficaria. Further studies on microflora, starch structure and characterization of flow behaviour are necessary in understanding the rheological properties of Oshikundu for process design and product quality evaluation
Malts: Quality and phenolic content of pearl millet and sorghum varieties for brewing nonalcoholic beverages and opaque beers
No full textBackground and objectives: The use of malted sorghum and pearl millet in the production of traditional foods and beverages is ubiquitous in Africa and India. However, there is limited industrial production and little data on the phenolic content and quality of pearl millet and sorghum malts of different varieties. Therefore, this study investigated the proximate content, malt quality, and phenolics of pearl millet (Okashana 2, Kantana, and Kangara) and sorghum (Macia and a landrace referred to as Red sorghum) varieties.
Findings: Malting increased the protein in all the varieties, except for Kangara. Germinative energies were >97% for all varieties, except for Red sorghum. Malt quality (reducing sugars, free amino nitrogen, and β‐amylase activity) was highest for Macia followed by Kantana. All pearl millet varieties and Macia had no condensed tannins. The total phenolic content and radical scavenging capacity decreased after malting for all the varieties.
Conclusions: Macia and Kantana can be candidates for industrial malting for brewing nonalcoholic beverages and opaque beers. Kantana and Red sorghum had higher amounts of phenolic compounds and can potentially be vectors of delivering phenolics into human diets.
Significance and novelty: This study investigated the phenolic content and quality of malts of different pearl millet and sorghum varieties, which can potentially be used to brew particularly low‐alcohol beverages
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Optimation of Ontaku/ Oshikundu: Pearl millet and sorghum malts quality and conveniet premix development
No full textA research dissertation submitted in fulfillment of the requirements for the Degree of Doctor of Philosophy in Science (Biochemistry)Oshikundu/Ontaku is a nonalcoholic, acidic, opaque fermented beverage. It is comprised of pearl millet (Pennisetum glaucum (L.) R. Br) meal/flour, commonly known as mahangu, malts of pearl millet or sorghum (Sorghum bicolour (L.) Moench) and/or brans (pearl millet). Brewing of oshikundu remains an art in households with no empirical improvement of a controlled fermentation flow process to give a consistent product. Some of the major limitations to the formal commercialisation of this brew are the absence of standardised malting process that gives a consistent malt quality and microbial safety. The lack of standard
ingredient ratios (flour/meal: malt: water) of brewing. Also, the sedimentation of adjunct particles at the bottom (dreg), thus creating the difference in viscosity of oshikundu. Welldefined fermenting microorganisms are not used, and the preparation method still relays on a laborious time-consuming process. Therefore, this study investigated conditions for malting, reduction of dreg, identification of fermenting microorganisms and formulation of ingredient ratio for an improved preparation process. Grains used in the study were collected from Omahenene Agricultural Research Station (20 15 harvest), of the Ministry of Agriculture,
Water and Forestry. Pearl millet varieties Okashana 2 (SDMV 93032), Kantana (landrace) and Kangara (SDMV 92040), while sorghum varieties are Macia (SDS3220) and landrace commonly referred to as red sorghum. Malts of the two cereals were prepared by steeping in static water at 20-22°C for 2 hours wet and 2 hours air-rest for a total of 8 hours and germinated at 30°C. Malts were dried between 50-55°C for 24 hours. Cereals germinative energy was above 90% as recommended for sorghum by the European Brewery Convention. Malting loss was high up to 30% in pearl millet varieties and Macia. Crude protein and fibre
were found . to increase following malting. Reducing sugars were not detected in
nongerminated pearl millet graiJ.'ls. Malts reducing sugars were statistically significant (p ~0.05) between cereals. The malt reducing sugars was as follows Macia> Red sorghum> time reduce dregs. Also, ingredient ratios were formulated by the use of dry ingredients premix for making oshikundu that was easy to prepare
Identification of lactic acid bacteria and yeast from Oshikundu using 16S and 26S rDNA gene sequencing
No full textOshikundu is brewed from fermentation of pearl millet (Pennisetum glaucum (L.) R.Br) meal commonly known as mahangu, sorghum (Sorghum bicolor (L.) Moench)/pearl millet malt, water and/or bran (from pearl millet). Consumption of this brew is daily in many households mostly in the Northern Namibia. Oshikundu samples were collected from north central and central region of Namibia. Isolation of lactic acid bacteria (LAB) was carried out on deMan Rogosa Sharpe (MRS), M17 and Rogosa agars, meanwhile malt extract and potato dextrose agars were used for yeast. DNA from isolates was amplified using standard polymerase chain reaction (PCR) and PCRâĂŞproducts were sequenced thereafter. Sequence was multiple aligned through Basic Local Alignment Search Tool (BLAST) and compared to the known DNA sequences in databases found in National Center for Biotechnology Information (NCBI)/GenBank database for LAB and yeast identification from oshikundu. Identified LAB were Lactobacillus plantarum, L. pentosus, L. fermentum, L. acidifarinae, L. spicheri, L. namurensis, L. zymae, L. brevis, Leuconostoc gurlium, L. delbrueckiee subsp. bulgaricus, L. buncheri and Pediococcus acidilactici. Meanwhile for yeast were Saccharomyces spp., and Pichi
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
