Study On The Texture And Flavor Of Low-salted Pickled Cucumber

Pickles are a general term for various vegetable products made from fresh vegetables and using different pickling techniques.They are mainly pickled cucumber,radish,ginger,kohlrabi,etc.,and have a long history in China because of their unique fragrance.It has certain nutritional value and has become one of the indispensable and deeply loved seasoning foods in people's daily life.The traditionally processed pickled vegetables are processed with high-concentration salt liquid to treat fresh vegetables and preserved by pickling.The traditional process of pickled vegetables with too much salt,long-term or excessive consumption of traditional high-salt pickles,will cause high blood pressure,heart disease and other cardiovascular and cerebrovascular diseases,which seriously threaten people's health,low-salt pickles and high-salt pickles More nutritious and healthy.However,when low-salt pickles are applied to fresh vegetables,the lack of salt will lead to a decline in the quality of the cucumber.The most direct effect is to cause a decrease in the hardness of the cucumber and loss of the original taste and flavor of the cucumber.In this study,cucumber was used as raw material to reduce salting and pickling of cucumber.By adding a compound pickling preparation and adding exogenous pectin methylesterase to improve the texture quality of low-salted pickled cucumber,low-salt pickled cucumber flavor substance The changes were analyzed and the main results are as follows:1.Process optimization of compound marinade preparations.Using low-salt cucumber as raw material,by monitoring the water activity,the optimal conditions for compound pickling of low-salted pickled cucumbers by single factor test and orthogonal test were 0.1%acetic acid addition,1.5%mannitol addition,and lactic acid.The amount of calcium added was0.06%.Under these conditions,the sensory score of the pickled cucumber in the composite pickled preparation was 93.625.The cucumber samples under the pickling method of low-salt pickles,pickled pickles,and high-salt pickles were subjected to TPA test,pectin content determination,ethanol insoluble content determination and scanning electron microscopy.The results showed that the addition of compound pickled preparations compensated for the decrease in hardness of pickled cucumbers caused by low salt content,and increased by 23%,15%and 2.1%respectively in hardness,pectin content and ethanol insoluble content.Scanning electron microscopy magnified 150 times,the composite marinade preparation maintained the integrity of the tissue cells better than the low salt pickles.2.Optimization of the process of adding exogenous pectin methylesterase.Pectin methylesterase converts high methoxyl pectin?HM?into low methoxyl pectin?LM?,and low methoxyl pectin crosslinks with Ca²⁺to form a strong calcium pectate network.To prevent the dissolution of pectin substances,thereby improving the quality of fruits and vegetables.In this experiment,the optimal conditions for the addition of exogenous pectin methylesterase to low-salt pickled cucumbers were determined by single factor test,orthogonal test combined with full TPA test:the calcium lactate addition amount was 0.4%,and the enzyme addition amount was 0.4%.The enzyme reaction temperature was 50?and the enzyme action time was 20 min;the exogenous pectin methylesterase was added and the sample without exogenous pectin methylesterase was compared.The results showed that the hardness,chewiness and pectin content of low-salt pickled cucumber samples with exogenous pectin methylesterase were higher than those of cucumber samples without pectin methylesterase,108.893 g,16.2,0.46 g Kg^-1;The results of electron microscopy supported the positive effects of pectin methylesterase from the microstructure.The addition of pectin methylesterase improved the texture properties of low-salted pickled cucumbers.3.Fresh cucumber,low-salt pickled cucumber,compound pickled pickled cucumber and high-salted pickled cucumber for the content of NaCl,reducing sugar,amino nitrogen,total acid and other flavor substances,organic acids,amino acids and nucleotides And the determination of the content,combined with the sensory evaluation found that the total flavor content of the pickled cucumber samples of the composite pickled preparations was higher than that of the low-salted pickled cucumber samples,and the organic acids,amino acids and nucleotides were more than the low-salt pickled cucumber samples.Pickled cucumber samples were more popular in sensory evaluation.The determination of the total flavor of the cucumbers with different sauce time was found:the flavor content began to increase from the second day of the sauce,and after the sixth day,the overall flavor decreased and stabilized.Gas chromatography-ion mobility spectrometry?GC-IMS?was used to analyze the volatile flavors of cucumber samples on the2^nd,4^thh and 6^thh day of the soy sauce.The results showed that when the low-salt cucumber sauce was stained to the fourth day,the volatile flavor was observed.The substance appeared and then stabilized,so the sauce was stained for 4 days as the best sauce time for low-salt pickled cucumbers.The types and contents of organic acids,amino acids and nucleotides of cucumber samples with 4 days of soaking were tested and compared with the cucumber samples before soy sauce.The cucumber samples after soy sauce were more organic acids,amino acids and nucleotides.Cucumber samples before pickling.In addition,other physical and chemical indicators,microbial indicators,and heavy metal indicators of soy-stained cucumber products meet the requirements of seasonings.