Effects Of Curing Methods And Time On The Quality Of Larou

Larou is a non-instant meat product made from fresh(frozen)animal meat as the main raw material,with other auxiliary materials,and processed by pickling,drying(or sun-drying,air-drying),smoking(or not smoking),etc.Well-known varieties include Cantonese-style bacon,Hunan bacon and Sichuan bacon,which are deeply loved by consumers for their unique flavor.Although the production process of bacon in different regions is different,curing is always an essential and basic link in the processing of larou.It can not only inhibit the growth of harmful microorganisms by reducing the water activity of larou,but also has a unique effect on larou.The taste and flavor formation are of great significance.At present,the marinating treatment of bacon processing in my country still relies on traditional production experience,and there is still a lack of in-depth research on the influence of process parameters such as marinating method and time on the quality of larou,which affects the modern industrial processing of traditional larou,and the maintenance and improvement of quality.For this reason,this paper firstly compares and analyzes the quality difference of bacon processed by dry-curing and wet-curing methods.The mechanism that marinating time affects the quality of larou is revealed.The main research contents and results are as follows:Using pork leg meat as raw material,the differences in taste and flavor of larou processed by dry-curing and wet-curing methods were compared and analyzed.The dry-cured larou had better texture quality,and its chewiness and hardness were significantly lower than those of the wet-cured bacon(P<0.05).The analysis of free amino acids and volatile flavor substances showed that the content of free amino acids and aldehydes in dry-cured larou was significantly higher than that of wet-cured larou,which were 1.5 times and 1.4 times that of wet-cured larou,respectively.Among them,the umami amino acid glutamic acid(Glu)and sweet amino acid alanine(Ala)increased by 56.38% and 36.44%,respectively,and aldehyde compounds closely related to fat and fragrance increased by 43.18%.Sensory evaluation confirmed that dry cured larou scored higher on taste,smell and overall liking.In conclusion,compared with wet curing,the quality of larou processed by dry curing is better.Using dry curing as the curing method,the changes of protein hydrolysis and flavor substances of pork during the curing process(0,5,10,15,20 d)were analyzed,and the mechanism of the effect of curing time on the quality of larou was preliminarily explored.The results showed that with the prolongation of marinating time,the p H value and salt content of pork increased continuously,and the degree of protein hydrolysis increased continuously.Pork marinated for 5 days had the best color and lustre,the muscle protein was significantly hydrolyzed,and the myofibrils were obviously fragmented and irregularly arranged.Texture analysis also showed that the hydrolysis of protein in pork mainly occurred in the first 5 days of marinating,and the muscle tissue of pork marinated for 20 days became loose and unsuitable for larou processing.Pickling for 5 d significantly increased the content of free amino acids and aldehydes such as nonanal in pork(P<0.05).Excessive pickling time resulted in a decrease in the content of umami amino acids and IMP,and an increase in the content of bitter nucleotides and amino acids.Adversely affects the taste of cured pork.The above results reveal that the study time affects the color,tissue structure and texture,protein hydrolysis and flavor formation of pork,which may affect the quality of processed bacon.Pork dry-cured at4°C for 5 days is suitable for high-quality bacon processing.Using dry curing as the curing method,the quality of larou processed with different curing times was compared and analyzed.The results showed that the larou cured for 5 d and cured for 10 d had better texture quality.Prolonged,the chewiness,adhesion and hardness of bacon decreased significantly(P<0.05),and the texture of larou marinated for more than 15 d was poor.Analysis of amino acids and nucleotides showed that larou cured for 5 d had the highest IMP content and EUC value,and cured for more than 5 d,the IMP and EUC contents of larou were significantly reduced,and the content of bitter amino acids in larou increased.The analysis of volatile flavor compounds showed that the larou cured for 5 days had the most types and contents of aldehydes,and the content of aldehydes decreased after the larou cured for more than 5 d,but the larou cured for a longer time had higher content.ketones and phenolic compounds.The sensory evaluation confirmed that the larou marinated for 5 days had the highest scores for taste,texture,aroma and overall preference.The above results confirmed that dry curing at 4°C for 5 d was the suitable curing condition for larou processing.To sum up,the marinating method and time have an important impact on the quality of larou.Compared with the wet curing method,the quality of the larou processed by the dry curing method is better.This may be the reason why the traditional larou processing generally adopts the dry curing method.Curing time may affect the quality of cured meat products by affecting the organization,protein hydrolysis and flavor formation of cured pork.Dry curing at 4°C for 5 d is a suitable curing condition for high-quality larou.