Effect Of Steeping Period On Yield And Acceptability Of Starch Extracted From Sorghum
Need help with a related project topic or New topic? Send Us Your Topic
DOWNLOAD THE COMPLETE PROJECT MATERIAL
Effect Of Steeping Period On Yield And Acceptability Of Starch Extracted From Sorghum
ABSTRACT
Starch was extracted from two kinds of sorghum bicolour grains (white and red) that had been steeped for 6, 8, and 12 hours using the wet milling method. The starch samples were then evaluated for yield, functional characteristics, and acceptability.
The output of the white variety varied from 0.45 to 0.70kg, whereas the red variety was 0.40 to 0.50kg. The outcome of their functional qualities was as follows: Bulk density, white (0.700 – 0.733g/ml) and red (0.723 – 0.753g/ml). Temperatures for gelation: white (70-72oC) and red (73-74oC).
The lowest gelation concentrations are white (0.60 – 0.90g/10ml) and red (0.70 – 1.00g/10ml). Metabolisable energy values: white (3.12 -3.82 kcal/g), red (3.73 -3.82 kcal/g). Glycosidic cyanide content: white (4.5–8.5%), red (8.5–10.5%).
Starchy samples steeped for shorter periods performed better in terms of functional characteristics, metabolisable energy value, and percentage moisture content. Starch samples soaked for longer periods produced higher yields but lower functional characteristics.
The white cultivar tested cyanide-free and performed better than the red kind. The sensory evaluation found a significant difference in colour and consistency between the samples at p(0.05) and p(0.01), respectively. However, there was no significant difference at p(0.05) and p(0.01) in taste, texture, and overall acceptance.
Chapter one
1.0 Introduction
Starch is a non-crystalline white powder that does not dissolve in cold water.
It can be hydrolysed into simpler molecules by heating with an acid or a specific enzyme. (Awan & Okaka, 1983).
Sorghum and millets store the majority of their carbohydrate as starch. It is made up of amylopectin, a branched chain polymer of glucose, and amylose, a straight chain polymer (FAO, 1992).
The digestibility of starch, which is dependent on hydrolysis by pancreatic enzymes, dictates cereal grain energy content. Sorghum starch is more digestible when it is processed using procedures such as steaming, pressure cooking, flaking, puffing, or Micronesian.
This has been attributed to the liberation of starch granules from the protein matrix, making them more vulnerable to enzymatic digestion (FAO 1992).
When starch is heated in water (wet heat), it forms a gel, which is crucial for thickening gravies and sauces, baking bread, and making custards (Awan and Okaka, 1983).
The textural features of grain-based foods are influenced by the starch’s physicochemical properties.
The behaviour of starch in water is temperature and concentration dependant (Malleshi and Desikachar, 1985).
Starches in general have relatively little water intake at room temperature, and their swelling power is extremely low. At higher temperatures, water uptake rises and starch granules collapse, resulting in the solubilisation of amylose and amylopectin to produce a colloidal solution. This is the gelatinisation stage. The temperature at which starch gelatinises is affected by both genetic and environmental factors.
Heat treatment of starch in a little amount of water causes swelling of the granules with little loss of soluble material and partial gelatinisation of the starch (Watson, 1970).
When cooked, gelatinised starch transitions from a soluble, dispersed, and amorphous form to an insoluble crystalline state.
This reaction is known as retrogradation or setback, and it is accelerated by cold temperatures and high starch concentrations (Rooney, 1991). Amylose, the linear component of starch, is more prone to degradation than amylopectin (Freeman and Bocan, 1973).
1.1 Statement of the Problem
Steeping sorghum for an extended amount of time wastes time and lends an unpleasant flavour to the starch recovered from the sorghum due to the action of spoiling microorganisms. As a result, it is necessary to lower the steeping duration and determine the influence on yield and sensory qualities.
1.2 The general goal of the study is to create a procedure for extracting starch from two different sorghum cultivars using varying steeping times.
The null hypothesis states that cultivar and steeping period have no effect on the quantity and functionality of extracted starches.
The specific purposes are:
To assess the impact of the steeping time on:
1. The yield of starch.
2. The Functional Properties of Starch
3. Organoleptic characteristics of starch.
4. The glycosidic cyanide content of the starch
5. The metabolisable energy value of the starch.
Need help with a related project topic or New topic? Send Us Your Topic