| In recent years,with the improvement of people’s living standards,more and more marine vegetables have come into people’s lives.Grateloupia filicina is a kind of edible economic seaweed,which has high nutritional value and edible value.However,there are few accessory products of Grateloupia filicina in the market.Therefore,we can develop an instant Grateloupia filicina product,which not only can realize the nutritional and active value of Grateloupia filicina,but also can effectively promote Grateloupia filicina to the market and maximize the economic value of Grateloupia filicina.(1)Using Grateloupia lanceolata collected in Dongshan as raw material,the nutritional components and senses of fresh Grateloupia lanceolata in different growth stages were determined and analyzed.The results showed that Grateloupia lanceolata as algae had more water content,accounting for about 90% of the total.Under the condition of dry weight,other nutrients were determined.The ash content,protein content,fat content and total sugar content of Grateloupia lanceolata were 12.08%~19.47%,13.76%~23.42%,0.1%~0.47% and 32.2%~63.77% respectively from January to April.Among the nine inorganic elements measured,the order of contents of four common elements is Na > Mg > K > Ca and five trace elements(Zn,Cu,Fe,Mn,Se),the contents of Zn and Fe are higher,the highest can be more than 0.1mg/100 g.Fourteen kinds of fatty acids were detected in different growth stages.Five kinds of saturated fatty acids accounted for the most,ranging from 62.76% to 75.62% of the total fatty acids,followed by six kinds of polyunsaturated fatty acids,accounting for 15.92% to 26.09%,of which EPA content was higher,up to 15.61%,and finally three kinds of monounsaturated fatty acids,accounting for 5.9% to 17.61%.Among the 17 common amino acids tested,the contents of 8 essential amino acids,7 nonessential amino acids and 2 semi-essential amino acids were not significantly different in January to March,but decreased significantly in April.According to the ideal protein model recommended by FAO/WHO,the Grateloupia lanceolata was suitable for food,and its flavor amino acids accounted for 45.5% to 48.5% of the total amino acids.The sensory evaluation showed that Grateloupia lanceolata had good texture and color and could be used to make ready-to-eat products.In conclusion,Grateloupia lanceolata is a kind of healthy algae product with high protein,high carbon water,low fat and rich nutrition.(2)In the development process of ready-to-eat Grateloupia filicina,we chose the process of color protection,blanching,crispness preservation and flavoring to optimize.In the Optimum Blanching experiment,the blanching time,temperature,concentration of sodium copper chlorophyll and concentration of zinc gluconate were the main factors affecting the color protection of Grateloupia filicina according to the single factor experiment and chlorophyll content as the index.Finally,the optimum experimental conditions were obtained by orthogonal experiment:Blanching Temperature 90℃,blanching time 3 min,zinc gluconate concentration 0.25%and chlorophyll.The concentration of copper and sodium was 0.2%.In the optimization experiment of brittleness-preserving technology,the main and secondary factors affecting the brittleness of Grateloupia filicina were calcium lactate concentration>soaking time>calcium carbonate concentration>calcium chloride concentration through orthogonal experiment and sensory evaluation.The optimum experimental conditions were as follows:soaking in mixed solution of 0.2%calcium lactate solution,0.1%calcium carbonate solution and 0.05%calcium chloride solution.At this time,the fragility of ready-to-eat Grateloupia filicina is the best.In the condiment process,salt,sugar,vinegar and capsicum oil were selected as the main indicators.According to the single factor experiments and sensory score,the best additions were salt 3%,sugar 3%,vinegar 5%,capsicum oil 7%.Instant Grateloupia filicina had the best taste and the highest public acceptance.(3)Instant Grateloupia filicina preservatives and storage experiments,under the same conditions,potassium sorbate and sodium diacetate were added into processed instant Grateloupia filicina respectively,and after 3 days,the total number of colonies contained in instant Grateloupia filicina was determined.The amount of preservatives added was 0.08% potassium sorbate and 0.2% sodium diacetate.Under room temperature storage conditions,with the increase of storage time,the total colony value of instant Grateloupia filicina showed an upward trend,while the sensory score showed a downward trend,while the pH value showed a downward trend first and then an upward trend.However,the total number of colony and sensory score of instant Grateloupia filicina remained unchanged with the increase of storage time at 4℃ In the experiment of the effect of different packaging methods on the quality of ready-to-eat Grateloupia filicina products,the total number of Grateloupia filicina colonies in the control packaging increased significantly at room temperature at 40 days,which resulted in the change of product pH.At the same time,the sensory score of Grateloupia filicina was also greatly affected.In vacuum packaging and modified atmosphere packaging,the total number of colonies was significantly smaller than that in the control packaging,and the change of pH continued to decrease,but did not increase.Therefore,the sensory score tends to differ slightly.Therefore,vacuum packaging and modified atmosphere packaging can not only delay the quality change of instant Grateloupia filicina,but also significantly extend the shelf life of Grateloupia filicina products.Although the total number of colonies in the control package kept rising at 4℃,the total number of colonies exceeded the stipulated 30000(Cfu/g).The total number of colonies in vacuum packaging and modified atmosphere packaging increased slowly,so the change of pH value and sensory score was slow.Storage temperature and packaging are important indicators affecting the quality of food products,and modified atmosphere packaging is more suitable for the development of ready-to-eat Grateloupia filicina products. |
