Changes in physicochemical properties of instant kunun zaki flours produced from millet (pennisetum typhoiduem) and malts of cowpea (vigna unguiculata) and soybean (glycine max) during storage.

Project Abstract

Instant kunun zaki is a popular fermented cereal beverage in Nigeria, prepared mainly from millet. This study investigated the changes in physicochemical properties of instant kunun zaki flours produced from millet (Pennisetum typhoiduem) and malts of cowpea (Vigna unguiculata) and soybean (Glycine max) during storage. The flours were blended in ratios of 10000, 9055, 801010, and 701515 for millet, cowpea, and soybean malts, respectively. The physicochemical properties evaluated included moisture content, pH, total titratable acidity, bulk density, water absorption capacity, and pasting properties. The samples were stored at room temperature for 90 days, and analyses were conducted at 0, 30, 60, and 90 days. Results showed that the moisture content of the instant kunun zaki flours ranged from 6.88% to 8.72%, with an increase observed during storage. The pH values ranged from 5.40 to 6.05, showing a decreasing trend over the storage period. Total titratable acidity increased from 0.13% to 0.37% during storage, indicating ongoing fermentation processes. Bulk density decreased from 0.65 g/cm3 to 0.54 g/cm3, while water absorption capacity increased from 1.74 g/g to 2.28 g/g, both showing significant changes during storage. Pasting properties exhibited fluctuations during storage, with peak viscosity decreasing and final viscosity increasing over time. Overall, the changes in physicochemical properties of the instant kunun zaki flours during storage were influenced by the malt types used in the blends. The incorporation of cowpea and soybean malts in millet flour resulted in variations in the properties of the instant kunun zaki flours, with significant changes observed in moisture content, pH, acidity, bulk density, water absorption capacity, and pasting properties. These changes indicate ongoing biochemical reactions and alterations in the structure of the flours during storage, potentially affecting the quality and sensory attributes of the final product. In conclusion, the study highlights the importance of monitoring the physicochemical properties of instant kunun zaki flours during storage, especially when blended with cowpea and soybean malts. Understanding these changes is crucial for maintaining the quality and extending the shelf life of instant kunun zaki products, contributing to the overall food security and economic value of these traditional beverages.

Project Overview

<p> </p><ol><li><strong>INTRODUCTION</strong></li></ol><p><em>&nbsp; &nbsp; &nbsp; &nbsp;Kunun zaki</em>&nbsp;is a traditional, non-alcoholic and non-carbonated beverage widely &nbsp;consumed in Northern Nigeria and is becoming popular in the South .It is consumed at any time of the day by both adults and children, as breakfast drink. It an appetizer and it is commonly served at social gatherings. The ingredients used in its manufacture include, millet (<em>Pennisetum</em>&nbsp;<em>typhoideum</em>), sorghum (<em>Sorghum vulgare</em>), maize <em>(Zea mays</em>), rice (<em>Oryza sativa)</em>, spices [ginger (<em>Zingiber officinale</em>), garlic (<em>Allium sativum</em>), red peeper (<em>Capsicum annuum</em>), black pepper (<em>Piper nigrum</em>), clove (<em>Syzygium aromaticum</em>)]. Also<em>&nbsp;Cadaba farinosa</em>, potatoes (<em>Ipomea batatas</em>)(Efiuvwevwere and Akoma, 1995<em>)</em>. Tiger nuts (<em>Cyperus esculentus</em>) and groundnut (<em>Arachis hypogea</em>) may be added to sweeten and enrich protein content.</p><p><em>Kunun zaki</em>&nbsp;is rich in carbohydrates, vitamins and minerals but it is low in protein (Ayo and Okaka, 1998). Sugar may be added instead of pepper to meet the demands of some consumers (Onuorah <em>et al</em>, 1987; Akoma <em>et al</em>&nbsp;2006). Some consumers consume <em>kunun zaki</em>&nbsp;without sugar or pepper (Adeyemi and Umar, 1994). Kunun zaki is accepted based on its colour (cream) and flavour (millet mixed with ginger flavour).</p><p>Traditionally, <em>kunun zaki</em>&nbsp;is produced by steeping the grains in water, wet milling with spices and sieving, the overall process taking 24 hours (Adeyemi and Umar, 1994). This traditional method has been improved by shortening the processing time to 12 hours by steeping the grains in warm water containing 15% sodium metabisulphate, wet-milling, liquefication and saccharification with enzymes in the grain, filtering, bottling and pasteurization at 80oC for 30 minutes before refrigeration at 4-8 oC (Gaffa and Ayo, 2002). Traditionally produced <em>kunun zaki</em>&nbsp;has a shelf life of about 24 hours (Adeyemi and Umar, 1994) at ambient temperature. The improved method can however extend the shelf life to 8 days after pasteurization followed by refrigeration storage (Osuntogun and Aboada, 2004) which can last for 90 days when chemical preservation is applied as has been achieved by FIIRO, Nigeria (Haard, 1998). Also instant <em>kunun</em>&nbsp;<em>zaki </em>flour has been produced by Dala Foods Limited Kano, Nigeria and commercialized <em>Kunun Tsamiya, </em>the product being made only from millet. Further work was done by Amazikwu (2007) where she produced instant <em>kunun zaki</em>&nbsp;flours from millet-cowpea malt and millet-soybean malt to enhance protein content and sensory quality. She also carried out sensory evaluation and the samples were rated acceptable by consumers. &nbsp;However no packaging or storage studies have been carried out on the instant powders and shelf life is also largely dependent upon the storage conditions and packaging materials used. This work is therefore a follow up of the work done by Amazikwu (2007). Against this background, this project was designed to produce instant <em>kunun zaki</em>&nbsp;flours from millet-cowpea malt and millet-soybean malt combinations and store in good flexible packaging material. Specific attention was therefore directed at;</p><p>(i) producing instant <em>kunun zaki</em>&nbsp;powders from millet-cowpea malt and millet-soybean malt by steam heating.</p><p>(ii) studying the changes in physicochemical and functional properties of the packaged flours during storage.</p> <br><p></p>