Sains Malaysiana 40(9)(2011): 1007–1011

Optimization of a Functional Cookie Formulation by Using Response

Surface Methodology

(Pengoptimuman Formulasi Suatu Biskut Berfungsi dengan Kaedah Respons Permukaan)

L.Y. Lee, K.S. Tan & S.L. Liew*

Food Science Program, School of Chemical Sciences & Food Technology, Faculty of Sciences & Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia

Received: 16 June 2010 /Accepted: 19 October 2010

ABSTRACT

A functional cookie formulation containing oligofructose, dietary fibre and lower calorie, fat and sugar contents than conventional cookies was optimized using Response Surface Methodology (RSM). Instant N-Oil II was used as a fat replacer, while Raftilose ®P95 was used as a sugar substitute with the addition of fructose to enhance sweetness. Selection of the optimal formulation was based on caloric content. An optimized formulation, V1, was obtained from the model Y = 4927.70 – 152.34X1 – 155.42X3 + 104.20X32 + 151.71X33 – 95.08X34, where Instant N-Oil II replaced 30% of butter and 24.4%, w/w (30.5g) fructose replaced 40.0%, w/w (50.0g) sucrose. Two additional optimized formulations, S1 and S2, were proposed which contained the same ingredients as V1, but both contained 19.0%, w/w (23.8g) Raftilose ®P95. Also, S2 had a higher fat replacement level (42%). A reference cookie prepared from a conventional recipe received significantly higher scores (P < 0.05) than the functional cookies V1, S1 and S2 in the sensory evaluation. However, when health benefits of the functional cookies were explained to the panel after the sensory evaluation had concluded, majority of the panelists stated that they would prefer S1, had they known of its health benefits. S1 contained 19.04% fat, 8.62% fructose and 0.74% sucrose, namely, significantly lower fat and sucrose levels and higher fructose content than the conventional cookie.

Keywords: Functional food; optimization; response surface methodology

ABSTRAK

Kaedah Respons Permukaan telah digunakan untuk mendapatkan formulasi optimum bagi menghasilkan biskut berfungsi yang mengandungi oligofruktosa, gentian diet dan kandungan kalori, lemak dan gula yang lebih rendah berbanding biskut biasa. Instant N-Oil II digunakan sebagai pengganti lemak dan Raftilose ®P95 digunakan sebagai pengganti gula. Fruktosa digunakan untuk meningkatkan rasa manis. Formulasi biskut optimum dipilih berdasarkan kandungan kalorinya. Formulasi optimum, V1 dihasilkan daripada model Y = 4927.70 – 152.34X1 – 155.42X3 + 104.20X32 + 151.71X33 – 95.08X34 dengan, Instant N-Oil II menggantikan 30% mentega dan 24.4%, b/b (30.5g) fruktosa menggantikan 40.0%, b/b (50.0 g) sukrosa. Dua formulasi tambahan telah dicadangkan berdasarkan model tersebut, iaitu S1 dan S2. Kedua-dua formulasi ini mengandungi ramuan yang sama seperti V1, tetapi juga mengandungi 19.0%, b/b (23.8 g) Raftilose ®P95. S2 juga mempunyai paras penggantian lemak yang lebih tinggi iaitu sebanyak 42%. Sampel biskut rujukan yang disediakan dengan menggunakan resipi biskut konvensional menerima skor yang lebih tinggi (P<0.05) dalam ujian penilaian sensori. Walau bagaimanapun, bila ciri-ciri positif biskut berfungsi dihuraikan kepada ahli panel selepas penilaian sensori selesai dijalankan, majoriti panel mengatakan bahawa mereka akan memilih biskut S1 setelah mengetahui ciri-ciri tersebut. Biskut S1 mengandungi 19.04% lemak, 8.62% fruktosa, 0.74% sukrosa serta mempunyai paras lemak dan sukrosa yang lebih rendah dan paras fruktosa yang lebih tinggi berbanding biskut formulasi rujukan yang dihasilkan daripada resipi konvensional.

Kata kunci: Kaedah respons permukaan; makanan berfungsi; pengoptimuman

REFERENCES

Association of Official Analytical Chemists (AOAC) 1990. Official Methods of Analysis of the Association of official Analytical Chemists. Arlington: Association of Official Analytical Chemists, Inc.

Box, G.E.P. & Draper, N.R. 1982. Measures of lack of fit for response surface designs and predictor variable transformations. Technometrics 24: 1-8.

Chang, A. 2002. Baking Made Easy. Kuala Lumpur: Chang & Lam Trading.

Fuller, G.W. 1994. New food product development: From concept to marketplace. Boca Raton, FL: CRC Press.

Furrie, E., MacFarlane, S., Kennedy, A., Cummings, J.H., O’Neil, D.A. & MacFarlane, G.T. 2005. Synbiotic therapy (Bifidobacterium longum/Synergy 1) initiates resolution of inflammation in patients with active ulcerative colitis: a randomised controlled pilot trial. Gut 54: 242-249.

Mazza, G. 1998. Functional Foods: Biochemical and Processing Aspects. Lancaster: Technomic Publishing Company.

Montgomery, C.D. 1991. Design and Analysis of Experiments. New York: John Wiley and Sons, Inc.

Myers, H.R. 1976. Response Surface Methodology. Michigan: Edwards Brothers.

ORAFTI Active Food Ingredients. Nutritional Benefits: Nutritional properties of inulin and oligofructose. http://www.orafti.com (3 Aug 2005).

Tungland, B.C. & Meyer, D. 2002. Non digestible oligo-and polysaccharides (dietary fiber): Their physiology and role in human health and food. Comprehensive Reviews in Food Science and Food Safety 1: 73-92.

*Corresponding author; email: siew@ukm.my