The Timing Of The Steak Cooking Time And Its Quality Evaluation

As a deep processing of beef products,steaks were gradually recognized by people because of higher nutritional value and unique flavor with the development of contemporary economy and integration of world culture,the consumption was also increasing.Due to processing technology mainly brought from abroad,domestic catering practitioners often made improper selection of cooking times for lacking of understanding the process of beef ripening,and grasped inaccurately about the maturity of fried steak,which resulted in unstable quality and poor taste of domestic steak products,and local brand was difficult to achieve a breakthrough.The objective of the study was to establish the appropriate cooking times for steak and it’s corresponding degree and provide a reference for the scientific and standardized production of steak processing industry for our country.By tracing the process of postpartum acid recovery of beef,and chose the appropriate cooking time for making steaks based on the quality of the beef during the row of acid.At the same time,the edible quality and nutritional value of steak cooked under different cooking times were evaluated.Firstly,the longest muscle of Simmental beef were used as research object,combined with it’s post-ripening process,the freshness index of beef were determined to define maturation time.Results showed that,beef riped for 168 h was in a fresh critical state under 4 ℃ ambient temperature,showed beef was fresh and edible riped within 168 h.Therefore,refrigeration for 12 h to 168 h after slaughter was defined as the optimum ripening time for the longest muscle of Simmental.Shear force,cooking loss,pressurized water loss,muscle stiffness index,protein thermal stability of beef which riped for 72 h,120 h and 168 h reduced significantly(P<0.05),showed better tenderness and water retention,and more susceptible to thermal denaturation.Therefore,ripening for 72 h,120 h and 168 h could chose as the appropriate cooking times for steak.Making different cooked system steak on the basis of selecting the better cooking time.In order to study the effects of cooking time and cooked system on texture characteristics,water retention,color,sensory quality,microstructure,volatile flavor of steak.Results showed that,with the extension of cooking time,the heating time required for the steak was greatly shorten due to the reducing of protein thermal stability.The cooked steak could obtain better texture characteristics and lower cooking loss rate relatively,the sensory score of overall acceptability,tenderness,flavor,and juiciness of steak were higher when cooking times for steak were ripening 72 h and 120 h.Microstructure showed that muscle fibers of steak under each cooked system were further separated,the sarcoplasmic membrane composed of collagen fibers continued to shrink and myofibril structure gradually became loose and irregular with the extension of cooking opportunities.Simultaneously,aldehydes,alcohols and hydrocarbons were main flavor compounds of steak formed during processing.Finally,the nutritional content of each steak sample were determined,mainly from the nutritional value of protein and fat to evaluate the nutritional value of steak totally.Results showed that,protein nutritional quality index of each steak were far greater than 1,further showed steak had a high protein nutritional characteristics.The ratio of amino acids of sweet amino acids to total amino acids was the largest in well done steak ripening for 168 h,showed more delicious flavor of steak.The digestibility of protein in medium well steak riped for 120 h was the highest,and could be more easier digested by body.C18:ln9c was the main component of fatty acids in each steak samples,was beneficial to human health,which content was the largest in medium well steak ripening for 168 h.