Application Of Plasma Activated Water In Chinese Sausage

Cured meat products are Chinese traditional food,among which Chinese sausage,Chinese ham,Chinese bacon,salted duck and so on are the most common.These products are popular with their good taste and long shelf time.Sodium nitrite is a food additive widely used in salted meat products,which has the functions of antibacterial,antisepsis,color fixing,oxidation resistance and flavor enhancement effects.However,nitrite has a certain amount of toxicity,improper use of which can cause safety hazards.For this reason,researchers continue to explore its substitutes and alternative technology.Plasma Activated Water(PAW)is a kind of solution prepared by Plasma treatment,which is rich in reactive oxygen and active nitrogen.It has good bacteriostatic effect and has been widely concerned in the food field.Studies have shown that meat products processed by PAW with sodium pyrophosphate are safe and non-toxic.At present,there is still a lack of research on the use of PAW as a nitrite substitute,which seriously restricts its application in food industry.Based on this,this paper takes PAW as the research object to explore the feasibility,advantages and disadvantages of replacing conventional nitrite for Chinese sausage,as well as its influence on the quality of Chinese sausage in the storage process,so as to provide theoretical basis for the development of safe nitrite substitute.The specific research conclusions are as follows:(1)Study on the active components of PAW and its effect on the quality of Chinese sausageThe effects of plasma treatment time on the types and contents of active components in PAW were investigated.The indexes of nitrite residue,total number of colonies,pH,pigment and chromogenic rate,degree of fat oxidation,protein decomposition,sensory evaluation of Chinese sausage cured by PAW were explored,and the changes of these indexes with plasma treatment were also investigated.The results show that nitrite is the main nitrogen-containing active substance in PAW,and its content steadily increases with time,and its pH decreases with time,while hydrogen peroxide is the main active oxygen substance,which slowly decreases with time.With plasma treatment prolonged,the nitrite residue,nitroheme,total pigment and chromogenic rate of the Chinese sausage cured by PAW increased,the TVB-N value decreased,the TBARS value decreased,and the sensory flavor evaluation increased overall.At the same time,compared with the control group without additives,,the total number of bacterial colony of the Chinese sausage cured by PAW decreased significantly.The experiment shows that PAW can stably play the role of antibacterial and preservative,color fixing,antioxidant and flavor enhancement when it is added into Chinese sausage.These effects are related to the active components of PAW,such as nitrite and hydrogen peroxide.(2)Short-term application effect of PAW as a nitrite substituteComparing the Chinese sausage without additives and the Chinese sausage with PAW,conventional sodium nitrite,celery powder,sodium pyrophosphate and sodium pyrophosphate combined with conventional sodium nitrite.The nitrite residual,pH,pigment and chromogenic rate,fat oxidation degree,protein decomposition,sensory evaluation and quality index of volatile flavor types,as well as the total number of colonies in Chinese sausage cured by PAW were investigated.The advantages and disadvantages of PAW was analyzed as a substitute for sodium nitrite.The results were as follows: compared with conventional sodium nitrite,PAW significantly reduced the nitrite residue in Chinese sausage,and significantly increased chromogenic rate.PAW is significantly better than conventional sodium nitrite in antibacterial effect,antioxidant effect,inhibition of protein decomposition and corruption and so on.Compared with celery powder,PAW is better than celery powder in antibacterial,reducing nitrite residue and adding flavor.There is no significant difference in antioxidant and chromogenic rate.And PAW is only inferior in inhibiting protein decomposition.The results of sensory evaluation combined with volatile flavor substances showed that PAW had similar optimization effect as conventional sodium nitrite,and the overall acceptability was significantly better than that of conventional sodium nitrite.Taking all factors into consideration,PAW with sodium pyrophosphate as buffer has advantages to replace nitrite in Chinese sausage application.(3)The influence of PAW on the quality of Chinese sausage during storageThe Chinese sausage without addition was regarded as the control group.Traditional sodium nitrite,PAW and celery powder were used to cure Chinese sausage respectively,followed by the vacuum packaging for four groups of Chinese sausage.After refrigerating at 4?for 4 weeks,the effect of PAW on the quality of Chinese sausage during storage was to explore via the measurement of the nitrite residue,the total number of colonies,pH,pigment and chromogenic rate,fat oxidation degree,protein decomposition and other indicators.Results show that during the period of storage,PAW group,the conventional sodium nitrite group and control group of the nitrite residue showed the trend of increasing,decreasing and then leveling off.That of the celery group showed the trend of reducing first,then increasing,and reached to the lowest level.However,at the end,the nitrite residue in the three groups besides the control group tend to be an approximation;In terms of total number of colonies,PAW group showed a trend of increasing,then decreasing and then increasing,which was different from the trend of firstly decreasing and then increasing in the other three groups.The level of PAW group remained significant low level during the whole storage period.For the pH,the changing trend of the four groups remained in the range of 6.1-6.4 as a whole,which was suitable for the microbial growth.In terms of chromogenic rate,the control group demonstrated the trend of firstly increased and then decreased,while the other three groups showed a similar trend of first decreased,then increased and then decreased.The chromogenic rate of PAW group was remarkablely better than that of the conventional sodium nitrite group.With regard to the TBARS value,PAW group showed an upward trend,while the other three groups showed an upward trend and then a downward trend.In the first three weeks,PAW group maintained a significantly lower level than that of other groups.In terms of TVB-N value,the variation trend of PAW group was significantly greater than that of the other three groups,showing a trend of fluctuating up and down.Taking all the factors into consideration,during the storage period,PAW with sodium pyrophosphate as buffer instead of conventional nitrite in Chinese sausage can not only keep the advantages of low nitrite content,but also has the advantages of good color,good antibacterial effect and low degree of fat oxidation.