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 Nigerian traditional beverage made from millet and legumes such as cowpea and soybean. This study aimed to investigate 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 millet, cowpea, and soybean were processed into flours, mixed in different ratios, and malted to produce instant kunun zaki flours. These flours were then stored under controlled conditions for up to 12 weeks, and their physicochemical properties were analyzed at regular intervals. During storage, the instant kunun zaki flours showed changes in various physicochemical properties. The moisture content of the flours decreased steadily over time, indicating gradual drying and stabilization of the products. The pH levels of the flours slightly increased during the initial weeks of storage, possibly due to microbial activities, but stabilized thereafter. The total titratable acidity of the flours also exhibited a slight increase, suggesting possible fermentation processes during storage. The color properties of the instant kunun zaki flours were monitored using the CIE L*a*b* color space system. The lightness (L*) values of the flours decreased slightly over the storage period, indicating some darkening of the products. The redness (a*) values showed fluctuations, while the yellowness (b*) values increased, indicating changes in the color attributes of the flours during storage. The texture profile analysis (TPA) of the instant kunun zaki flours revealed changes in texture parameters such as hardness, cohesiveness, springiness, and chewiness during storage. The hardness of the flours increased gradually, while cohesiveness and springiness decreased over time. These changes in texture properties could be attributed to moisture loss and possible starch retrogradation during storage. Overall, the storage of instant kunun zaki flours produced from millet and legume malts led to changes in their physicochemical properties. Monitoring these changes is crucial for ensuring the quality and shelf life of the products. Further research is needed to optimize storage conditions and packaging materials to maintain the desired physicochemical properties of instant kunun zaki flours for extended periods.

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>