Research On The Technology Of Modified Atmosphere Packaging Preservation Of Sturgeon Fillets

Sturgeon is one of the rare fish with high nutritional and hygienical value,which is also called "soft gold".The study of technology on the preservation of fresh sturgeon is of practical value and great significance.This work is focused on modified atmosphere packaging(MAP)technology combined ozone,ultraviolet radiation preprocess to preserve the quality of sturgeon and prolong the shelf life.The results of research are as follows:1.The study on storage temperature of sturgeon fillets In contrast to normal temperature,the paper studied the effect of different temperature on sturgeon fillets quality. The results showed that the shelf life of sturgeon fillets were 5-6 days under normal temperature and were not more than 9-10 days under 3℃and 5℃.However,the fresh quality of sturgeon fillets was still very good on the twelfth day under 1℃.So 1℃was the optimum temperature for storing sturgeon fillets.2.The study on load ratio of sturgeon fillets The experimentation studied the effect of load ratio were 10%,20%,30%and 40%on sturgeon fillets with MAP storage. The results showed that load ratio had no distinct effects on the quality of sturgeon fillets.3.The study on gas composition of sturgeon fillets Compared to air storage, it studies the effect of different temperature on sturgeon fillets' refrigeration quality.The rusults showed that when the gas composition satisfied CO₂≥50%and 5%≤O₂≤10%, sturgeon fillets will be kept with the better sensory quality and lower pH value and TVB-N value,especially for effective control on large enterobacteriaceae count,and the highest count is 5300 MPN/100g on the 28^thday,but total aerobic count were than 5.5*10⁵ cfu/g, and the water holding capacity was reduced to 80%.So 50%CO₂+10%O₂+40%N₂ MAP was the best for sturgeon fillets quality,with shelf life of 24 days which is 8 days more than CK.4.Effects of MAP combined ozone preproeess on sturgeon fillets quality Compared with the control group,effects of ozone preprocess with 10 min,20 min,and 30 min separately on extending sturgeon fillets storage lifetime were studied.The results showed that ozone preprocess significantly reduced total bacteria count more than 90 percent,which well controlled pH and TVB-N value without affecting water holding capacity with 20 min,also could improve sensory quality.This test indicated that the effects of MAP combined 20 minutes' ozone preprocess could well preserve sturgeon fillets quality,with a shelf time of 27 to 29 days.5.Effects of MAP combined ultraviolet radiation preprocess on sturgeon quality Compared with the control group,effects of ultraviolet radiation preprocess with 5 min,10 min,and 15 min on extending sturgeon fillets storage lifetime were studied.This test indicated that MAP combined 10 minutes' ultraviolet radiation preprocess could kill 98 percent original bacteria,and then controlled pH and TVB-N value without reducing water holding capacity,which can help prolong the shelf life to 28 days but decreased the sensory evaluation during the late stage of the storage.