ارزيابي حسي و تعيين ماندگاري پخشينه كم چربي و كم ترانس

Sensory evaluation and shelf-life of low-fat and low-trans spreads

Background and Objective: The prevalence of obesity and cardiovascular diseases in the world has prompted production oflow-fat and low-trans-fatty acid margarine-like products or low-fat and low-trans spreads. An increase in water content of such products can affect their sensory characteristics and shelf-life. The aim of this study was sensory evaluation and shelf-life detcrrnination of low-fat and low-trans spread samples produced at a laboratory scale. Materials and Methods: Six samples of low-fat (40%) and low-trans «1 %) spreads were produced at a laboratory scale (2kg) by combining three oil phases and two stabilizers, i.e., F, and F, formulas with palm stearin and canota oils (40:60) and sodium alginate (F,), or modified waxy maize starch or MWMS (F2) ; F3 and F4 formulas with fully hydrogenated soybean oil (flake) and soybean oil (25:75) and sodium alginate (F]), or MWMS (F,); F, and Fo formulas with palm, cottonseed and canola oils (40:40:20) with sodium alginate (Fe), or MWMS (Fg), and full fat spread or Fl (80%fat) with palm stearin and canola oils (40:60), without stabilizer. as a control. Sensory evaluation (surface texture, spreadabiliry. flavour and mouth feel, and overall acceptance) was carried out by 30 in-house panelists (ranking method). Shelf-life of the spread samples stored in refrigerator (5°C) was determined by measuring peroxide value, oiling off and microbial characteristics (total aerobic bacterial count, and mold and yeast counts). Results: There were significant differences among the samples as regards overall acceptance (p<0.05). Sensory evaluation showed similar results for F2 and Fl , and samples with MWMS had better acceptance compared to samples containing sodium alginate. Peroxide value did not reach the discard point (5meq/kg), even after 10 weeks of storagc. Results of oiling off tests were satisfactory for most samples; oiling off was found only in F, and F" after six weeks of storage. All samples reached the discard point after 10 weeks of storing at 5°C, taking into account total bacterial and mold and yeast counts. Conclusion: The final ranking of the spread samples based on the nutritional value (P/S+ T), physical characteristics. sensory evaluation and shelf-life was as follows: Fl>F,>F,>F6>Fj>F3>F,. Considering the necessity of production of low-fat and low-trans-fatty acid products from a nutritional and public health point of view, the F, formula is recommended for further research.