Effects of yuzu juice-supplemented diets on prevention of dark muscle discoloration during storage in yellowtail Seriola quinqueradiata and detection of yuzu flavor components in fish meat

Abstract

To improve the commercial value of cultured yellowtail, the following two experiments were conducted. In theˆrst experiment, the anti-oxidant eŠects of yuzu Citrus junos juice on prevention of dark muscle discoloration during storage in yellowtail Seriola quinqueradiata were investigated. Yellowtails were fed one of four diets supplemented with yuzu juice (0, 12.5, 25 and 50 mL/kg diets) for 40 days. Growth performance was not signiˆcantly diŠerent among the dietary groups. Dark muscle discoloration was reduced inˆsh fed yuzu juice-supplemented diets during storage at 4°C. These results indicate that yuzu juice-supplemented diets prevent dark muscle discoloration without aŠecting the growth of young yellowtail after 40 days of feeding. In the second experiment, the ac-Experimental diets Control Yuzu 12.5 Yuzu 25 Yuzu 50 Ingredients (g/kg) Fish meal 1 650 Krill meal 2 50 Pollack liver oil 3 80 a-Starch 80 Cellulose 75 Vitamin mixture 4 20 Mineral mixture 5 20 CMCNa 20 Guar gum 5 Yuzu juice 0 12.5 25 50 Water 450 437.5 425 400 Proximate composition (g/kg) 6 Crude protein 501 496 499 495 Crude fat 166 162 159 165 Crude ash 123 120 116 117

Effects of Yuzu (Citrus junos) Peel from Waste as an Aquaculture Feed Supplement on Growth, Environmental Load, and Dark Muscle Discoloration in YellowtailSeriola quinqueradiata

“…All measurement values were similar to previous experiments (Seno-o et al, 2008;Fukada et al, 2010). Yuzu paste supplementation did not affect the levels of serum components, which suggests no negative effects on fish health.…”

“…No significant changes were observed in moisture, crude fat, and crude ash levels of the whole body or liver among the diet groups. A previous experiment in yellowtail showed a decreasing trend in the fat levels of fillet and liver after addition of yuzu juice to the diet (Fukada et al, 2010). This trend was not observed in fish fed yuzu paste-supplemented diets.…”

“…Furthermore, the natural antioxidant ergothioneine, extracted from mushroom (Flammulina velutipes) cultured medium, has been proven to suppress dark muscle discoloration of yellowtail (Bao et al, 2009). Addition of yuzu juice to fish feed has significantly prevented dark muscle discoloration of yellowtail (Fukada et al, 2010).…”