Cryoprotective Effects of Carrageenan on Pre-prepared Gel of Minced Shrimp (Litopenaeus Vannamei) During Frozen Storage

Minced shrimp products have gradually become popular among consumers due to their convenient consumption. The changes in physiochemical properties occurred because of low temperature storage. To investigate the cryoprotective effects of carrageenan on the pre-prepared gel of minced shrimp gel during frozen storage, the variation trends in texture properties of shrimp heated gel (made by chopping, pre-preparing, freezing, and heating) and rheological properties of pre-prepared shrimp gel (made by chopping, pre-preparing, freezing, and thawing) with different carrageenan additions compared to commercial cryoprotectant were analyzed. Results showed that carrageenan could significantly improve breaking force, gel strength of heated gels, and storage modulus and loss modulus of pre-prepared gels. According to better texture properties, the group with 2% carrageenan (C-2%) was selected for the further experiments. The lower immobilized water amplitude exhibited that carrageenan could stabilize the mobility degree of water in pre-prepared gels while transferring free water into immobilized water after heating. Meanwhile, carrageenan had outstanding effect on preventing exposure of total sulfhydryl group due to protein oxidation. There were no tremendous changes in protein functional groups due to addition of carrageenan, while it could maintain the stability of the gel system on account of increasing alpha-helix contents. The little significant differences were observed in protein composition during frozen storage, while the cross-linking and aggregation have been increased due to the addition of carrageenan. Overall, carrageenan was expected to be an effective substitute for commercial cryoprotectant to promote the development of diversified pre-prepared minced shrimp products.

Automated summary

In this study, the cryoprotective effects of carrageenan on minced shrimp gel during frozen storage were investigated. The results showed that carrageenan significantly improved the texture properties and rheological properties of the gel, as well as prevented protein oxidation. Carrageenan also maintained the stability of the gel system by increasing the alpha-helix contents. Additionally, carrageenan promoted cross-linking and aggregation in the gel. Overall, carrageenan could be an effective substitute for commercial cryoprotectant in the development of pre-prepared minced shrimp products.