The Effects of Walnut Oil and Kefiran on the Texture and Rheological Properties of Ice Cream

Subject Areas : Microbiology

P. Habibi ¹ (دانش آموخته کارشناسی ارشد دانشکده علوم و صنایع غذایی، دانشگاه کشاورزی و منابع طبیعی گرگان، گرگان، ایران)
M. A. Ziaiifar ² (استادیار گروه مهندسی و طراحی مواد دانشکده علوم و صنایع غذایی، دانشگاه کشاورزی و منابع طبیعی گرگان، گرگان، ایران)
F. Khodayean Chegini ³ (دانشیار گروه علوم و مهندسی صنایع غذایی، پردیس کشاورزی و منابع طبیعی دانشگاه تهران، کرج، ایران)

Received: 2016-08-25 Accepted : 2016-08-25 Published : 2016-09-22

Keywords: Ice Cream, Kefiran, Rheology, Texture, Walnut Oil,

Abstract :

Introduction: The replacement of saturated fatty acids by unsaturated fatty acids in ice cream formulation for patients with cardiovascular disease is quite desirable. In addition due to the positive nutritional effects of kefiran this product might be employed as a stabiliser in dairy products. Materials and Methods: Samples of ice cream, containing kefiran (0.1-0.5%) and walnut oil (0-8%), were produced. The viscosity, rheology and texture (hardness and adhesion) were evaluated and the obtained data concerned with the mentioned tests were analysed using a central composite design with response surface method. Results: Kefiran and walnut oil exhibited significant effects on the samples of ice cream. The addition of kefiran significantly increased the viscosity, consistency coefficient and reduced the flow index, hardness and adhesion (p<0.05). By increasing the concentration of walnut oil, consistency coefficient, hardness, adhesion, apparent viscosity decreased and flow index increased. Interaction of kefiran and walnut oil also had significant effect on viscosity reduction (p<0.05), but did not have significant effect on other characteristics (p>0.05). Conclusion: 2% of walnut oil and 0.5% of kefiran might be regarded as a good combination to obtain a product with suitable rheological characteristics.