Preparation And Deodorization Of Puffer Fish(Takifugu Rubripes) Skin Gelatin

The study investigated physiochemical and functional properties of gelatins from tiger puffer skin(GTPS)extracted with warm-water method at 45,55 and 65 ? for 3,6 and 12 h.The yield of GTPS increased from 28.1 % to 41.5 % as temperature increased from 45 to 65 ? and time prolonged from 3h to 12h(p<0.05)GTPS45 exhibited strong ?-,?-,?1-and ?2-chains,but they faded with the presence of fragments(<80 KDa)in other GTPS.As the increase of temperature and time,amide I and A were shifted to higher wavenumber and their amplitudes in GTPS65-12 decreased.Lightness declined while redness and yellowness were enhanced.Gel strength was in a range of 144.5-79.8 g,where it of GTPS45-3 was the highest while it of GTPS65-12 was the lowest(p<0.05),coincided with the longer relaxation time of T22 for immobilized water.Decline in gelling and melting temperature was observed when temperature and time increased.EAI and ESI increased as time prolonged or temperature climbed(p<0.05),in agreement with the form of emulsion droplet by microscopy.Both category and level of volatilecompounds increased GTPS65-12 and 55-12 compared with those in GTPS45-12.Results suggest that temperature and time greatly affect the properties of GTPS.To ensure good properties,GTPS should be extracted at a temperature of 45-55 ? for less than 12 h.Then In this study,GTPS55-3 was used to investigate the effects of activated carbon(PAC),?-cyclodextrin(?CD)and yeast(YE).The results showed that activated carbon,?-cyclodextrin and yeast had obvious effects.Among them,the best effect of activated carbon(p<0.05)was better than that of ?-cyclodextrin and yeast.The color analysis showed that the lightness of the gelatin treated by ?-cyclodextrin was higher than that of the other groups(p<0.05),but the difference between redness and yellowness was less than that of the control group.The b* value of gelatin was higher(p<0.05)after the deantion of yeast.All GTPS samples have three clear high molecular weight bands and two low molecular weight bands.And ?-cyclodextrin can significantly reduce the gel strength of gelatin and make the amide-A belt move in the direction of high wave number.The number of hydrogen bonds decreases and the relaxation time is prolonged,reducing the capacity of the binding water.The gelatin after deodorization generally improves the emulsification stability,and the yeast has the best effect.To sum up,the use of activated carbon to remove the fishy effect is the best,and has little effect on the physical and chemical properties of gelatin.