ABSTRACT
Four formulas of canned tuna in spring water and tuna in mayonnaise and pouched tuna in salad cream and tuna in thousand island cream with added inulin were developed for commercial production. The effects of the addition of a prebiotic (inulin, Orafti®-HP) on the color and sensory properties of these products were studied. For inulin concentrations studied (3, 5, 7 and 10 %, w/w) caused more intensed yellow and red colors. Hedonic sensory values of tuna packed in spring water and in mayonnaise showed no significant differences (p > 0.05) among products with different inulin addition levels (3, 5, 7 and 10 %, w/w) in terms of color, flavor, sweetness and overall characteristics. However, when packed in thousand island cream, significant differences (p < 0.05) in color and overall characteristics were found when inulin was added higher than 7 %. Tuna in salad cream showed significant differences (p < 0.05) in color, flavor, sweetness and overall characteristics at higher than 7 % inulin. The panelists showed acceptable overall liking scores at upto 7 % inulin of all tuna products. The thermal sterilization process resulted in approximately 20 % decrease in final inulin content. The calculated residual fructans of finished products at shelf life of 3 years were 3.01, 2.78, 2.90 and 2.84 % for tuna in spring water, tuna in mayonnaise, tuna in thousand island and tuna in salad cream, respectively. Considering formula cost in a commercial production and the recommended daily intake (RDI) of inulin in the finished product at end of shelf life (≥3 g/d), an addition of 5 % inulin for tuna in spring water and 7 % inulin for tuna in mayonnaise, tuna in thousand island and tuna in salad cream are recommended.
