Optimization of Ingredients Formulation in tow Grades Surimi for Improvement of Gel Strength

저급 수리미의 젤 강도 증강을 위한 첨가물의 최적화

The increasing price of surimi has affected the economical benefits of surimi based food industry, To maintain gel strength in low grade surimi, the optimum formulation adding functional proteins to low grade surimi is required. The objective of this study was to develop the optimum formulation of ingredients in making gels in low grade surimi on the addition of functional non-muscle proteins to low grade surmi by measuring rheological properties of the gels. The rheological qualities of the cooked gels made with A and RA grade surimi on the effects of adding five kinds of starches (potato, wheat, waxy maize, corn and modified corn) and four kinds of functional proteins (bovine plasma protein, dehydrated egg white, soy protein isolate and whey protein concentrate) to the gels were evaluated, The gel styengths at cooking with A and RA grade surimi were decreased with increasing the added starches. The kind of starches added affected little the gel strengths in Rh grade surimi, while potato and corn starches decreased at the least in gel strengths of the gel made with A grade surimi with increasing the concentration of starches. The bovine plasma protein (BPP) significantly increased the gel strength, especially in RA grade surimi, but BPP decreased the whiteness of the gel. Therefore, the optimum content of BPP was up to $2\%$ because of the whiteness of the gels in RA grade surimi, The optimum formulation for the gel with RA grade surimi to satisfy the gel strength of 1000$\times$g and $78\%$ moisture was $40.9\%$ surimi, $9.1\%$ dehydrated egg white (DEW) and $0.9\%$ starch, while that with A grade surimi under the same condition was $37.9\%$ surimi, $6.6\%$ DEW and $3,4\%$ starch.

전분은 종류에 관계없이 첨가량을 증가시킴에 따라 gel 강도는 저하하였으며, RA급 냉동 surimi은 전분의 종류에 큰 영향을 받지 않은 반면, A급은 감자전분 및 수식 옥수수전분이 농도 증가에 따른 gel 강도 감소에 가장 적은 영향을 미치는 것으로 나타났다. WPC, DEW 및 SPI는 첨가량이 증가함에 따라 gel 강도는 감소하였으나, BPP는 gel 강도를 증가시키는 것으로 나타났으며, 이 같은 효과는 RA급에서 현저하였다. BPP의 gel 강도 증가 효과는 낮은 변성온도와 열 변성에 따른 구조 변화가 어육 gel의 matrix 강화에 영향을 미치는 것으로 판단된다. RA급을 이용한 어육 gel 제조시 백색도에 큰 영향을 미치지 않는 $2\%$ 범위 내에서 gel 강도 강화를 위해 사용할 수 있는 것으로 나타났다. Gel 강도 1000$\times$g를 제한 인자로 하였을 때, 냉동 surimi의 소모량이 가장 적은 formulation은 A급에서는 A급 surimi $37.8\%$ DEW $6.6\%$, 전분 $3.4\%$ 였으며, RA급에서는 RA급 surimi $40.9\%$, DEW $9.1\%$, 전분 $0.9\%$이었다.