University of Ghana, College of Basic and Applied Sciences, School of Agriculture, Department of Agricultural ExtensionBudu, A.S.Saalia, F.K.Sakyi-Dawson, E.Atengdem, B. P.Dongdem, A.M.2014-08-072017-10-132014-08-072017-10-132013-03http://197.255.68.203/handle/123456789/5485Thesis (MPHIL) - University of Ghana, 2013Thesis (MPhil) - University of Ghana, 2014The most important processed form of peanuts in Ghana is peanut paste. The predominant use of this peanut paste is for the preparation of soup. This soup is a traditional delicacy enjoyed in most countries of West Africa. However, peanut soup preparation is time consuming and the soup has poor keeping qualities. Furthermore, the safety of peanut soup is of great concern because of perceptions of adulteration of the paste on the Ghanaian market and the high probability of aflatoxins contamination of peanuts. This study aimed to develop a process for a safe and consumer acceptable canned peanut soup base and to evaluate the product characteristics. A suitable variety of peanuts (i.e. Chinese variety) was selected from among four most popular local varieties (Manipintar, Chinese, Sinkarzie and Bugla local). The selection was based on proximate composition, and variability in physical characteristics (seed dimensions and bulk density) as well as availability of the variety of peanuts. The manual color sorting method to minimize aflatoxin levels in peanuts was used and the aflatoxins levels monitored using HPLC procedures. To determine the optimum proportions of secondary ingredients required for the soup, eight (8) ingredient formulations were generated using mixture designs procedures (extreme vertices option) for the three secondary ingredients (pepper: 5 – 15g, Onion: 100 – 180g, tomato paste: 75 – 150g). The ingredient formulations were evaluated by 48 panelists in an optimization study and validated to obtain the most acceptable secondary ingredient formulation for peanut soup base. A 3 X 3 full factorial design for retort processing temperature (115, 120, 125°C) and processing time (40, 50, 60mins.) was used to determine the most adequate thermal process for a canned peanut soup base. The physical characteristics of the peanuts showed significant difference among varieties (p < 0.05). The Chinese variety was selected for the project because it is the predominant variety in major markets of Greater Accra Region of Ghana and also the most cultivated variety among peanut farmers. Its seed dimensions - width and length - were also most variable (standard deviations ±0.62cm and ±2.27cm) compared to the other varieties which made it a better choice to be milled into peanut paste rather than used for products that may require uniformity in seed dimensions. Total peanut weight loss due to the colour sorting was high (25%) however the total aflatoxin concentration of the clean sorted peanuts was below 4μg/kg, which is one of the strictest maximum limit of total aflatoxins in peanuts acceptable in some Countries. The most suitable secondary ingredient formulation for peanut soup base was determined to be 12.30g pepper, 100.80g onion and 146.90g tomato paste per 300g of peanut paste. The limits of the thermal process for canned peanut soup base were established to range from 122°C to 124°C for 51 to 44mins respectively to achieve shelf-stability. The estimated sterilizing values (F o ) under the thermal process conditions ranged from 0.04 to 1.92mins. The minimum thermal process treatment of 115°C for 40mins recorded the highest plate counts of 10,000cfu/g for APC and also 10,000cfu/g for Yeasts and Moulds Count. Peanut soup base subjected to the severest thermal process (125°C for 60mins) yielded no observable growth (at dilutions 10 2 ml) for both APC and Yeast and Moulds count. Findings from this study show that a virtually aflatoxin-free peanut soup base, acceptable to consumers can be obtained by manually sorting peanuts, roasting to an appropriate colour, grinding into a smooth paste, mixing with predetermined proportions of secondary ingredients, and subjecting it to an established thermal process schedule.xv, 108p.xi, 77p, ill.enThesisUniversity of GhanaUniversity of Ghana