Method for improving astaxanthin content of dried freshwater shrimp product through ultrasonic blanching pretreatment

Abstract

The invention relates to a method for improving the astaxanthin content of a dried freshwater shrimp product through ultrasonic blanching pretreatment, and belongs to the field of deep processing of agricultural products. The method comprises the steps: selecting mature and fresh freshwater shrimps as raw materials; cleaning, removing shrimp beards and empennages, and then carrying out variable-frequency ultrasonic blanching pretreatment; in the first stage, putting pretreated freshwater shrimps into clear water according to a material-water ratio of 1 4, and setting the water temperature to be 75-85 DEG C, the ultrasonic frequency to be 60KHz, the power density to be 0.45-0.58 W / cm2 and the treatment time to be 3-5min; in the second stage, taking out he freshwater shrimps and putting intoa NaCl solution with the mass fraction being 2%-4%, wherein the material-liquid ratio is 1 4, the water temperature is set to be 65-75 DEG C, the ultrasonic frequency is set to be 25 KHz, the power density is set to be 0.65-0.72 W / cm2 , and the treatment time is set to be 4-6 min; and finally, performing normal-pressure hot air drying, wherein the hot air drying temperature is set to be 55-65 DEGC, the air speed is set to be 2.0-3.0 ms, and the drying time is set to be 6-8 h. The variable-frequency ultrasonic blanching effectively removes the fishy smell of the freshwater shrimps and reducesthe content of volatile basic nitrogen in the dried products, and compared with conventional blanching, the fresh amino acid content of the dried freshwater shrimp products is increased by 17%-22%, and the astaxanthin content is increased by 18%-23%.

Description

technical field [0001] The invention relates to a method for increasing the content of astaxanthin in dried green shrimp products through ultrasonic blanching pretreatment, and belongs to the field of intensive processing of agricultural products. Background technique [0002] Freshwater shrimp, scientific name Macrobrachium nipponense (Macrobrachium nipponense), belongs to the phylum Arthropoda, Crustacea, Decapod order, Macrobrachium genus. Aquatic products export foreign exchange earning products. Freshwater prawns are widely distributed in freshwater waters in my country, and are distributed in Anhui, Jiangsu, Shanghai, Zhejiang, Fujian, Jiangxi, Guangdong, Hunan, Hubei, Sichuan, Hebei, Henan, Shandong and other places. Green shrimp is delicious and nutritious, especially the natural astaxanthin contained in the body is a kind of carotenoid, which has a strong antioxidant capacity, can remove nitrogen dioxide, sulfide, disulfide, etc., and can also reduce lipids Peroxi...

AI Technical Summary

Problems solved by technology

However, due to the high temperature of the conventional hot blanching treatment, it is easy to cause a large loss of the nutritional and active components of the freshwater shrimp raw materials, especially the natural astaxanthin content in its body.

At present, there is no relevant research report on improving the content of astaxanthin in dried shrimp products by ultrasonic blanching pretreatment method