Quality changes of stabilizer-free natural peanut butter during storage
The storage stability of preservative-free peanut butter was evaluated for changes in physicochemical quality including moisture content and water activity, microbiological properties, oxidative stability and textural quality in terms of spreadability and firmness. The study was conducted for 16 weeks at storage temperature of 10, 25 and 35 °C on natural and pure peanut butter produced from two varieties of peanuts, the Virginia and Spanish TMV-2 varieties of China and India origin, respectively. The peanuts were ground using a high speed grinder for 2.5 and 3.0 min to produce peanut butter without addition of other ingredient. The natural peanut butter exhibited stability and had acceptable microbial count during storage. Storage at 10 °C gave similar textural quality with commercial product until week 8 and without appreciable loss in oxidative stability until week 12. At higher storage temperatures of 25 and 35 °C, oxidative stability was shortened to 4 weeks of storage. Among the factors of storage temperature and time, grinding time and peanut variety, storage temperature had the most significant effects on quality changes of natural peanut butter.
KeywordsNatural peanut butter Storage Physicochemical properties Microbial count Oxidative stability Textural quality
Authors are thankful to the Ministry of Education of Malaysia and Universiti Sains Malaysia for their financial support of scholarship programme under Academic Staff Teaching Schemes (ASTS/SLAI), and Universiti Putra Malaysia for funding of this project through Research University Grant Scheme No. 05-02-11-1399RU.
- AOAC (1996) Official methods of analysis. Washington, D.C., Association of Official Analytical ChemistsGoogle Scholar
- FDA (1998). Bacteriological Analytical Manual. Chapter 3 (Edition 8, Revision A)Google Scholar
- Kirk RS, Sawyer R (1991). Pearson's composition and analysis of foods, 9th edn. Longman Sci Tech Harlow, pp 609–617Google Scholar
- Mallia S, Piccinali P, Rehberger B, Badertscher R, Escher F, Schlichtherle-Cerny H (2008). Determination of storage stability of butter enriched with unsaturated fatty acids/conjugated linoleic acids (UFA/CLA) using instrumental and sensory methods. Int Dairy J 18(10–11):983–993CrossRefGoogle Scholar
- Schorno AL, Manthey FA, Hall III CA (2009). Effect of particle size and sample size on lipid stability of milled flaxseed (Linum usitatissimum L.). J Food Process Preserv 34(2010):167–169Google Scholar
- Suchoszek-Łukaniuk K, Jaromin A, Korycińska M, Kozubek A (2011). Chapter 103 - health benefits of peanut (Arachis hypogaea L.) seeds and peanut oil consumption. In: Preedy VR, Watsons RR, Patel VB (eds) Nuts and seeds in health and disease prevention. Academic Press, San Diego, pp 873–880CrossRefGoogle Scholar
- United States Department of Agriculture (2010). Commodity requirements PP12 peanut products for use in domestic programs, farm service agency (FSA), Washington, DCGoogle Scholar
- United States Department of Agriculture (2011). Grading manual for peanut butter, USDA, Washington, DCGoogle Scholar
- Woodroof JG (1983). Peanut Butter. In: JG Woodroof Peanuts: Production, Processing, Products. The AVI Publishing Company, Westport, Connecticut, pp 181–225Google Scholar