Study On The Compound Plant Beverage Of Special Type Of Seaweed

Seaweed is rich in a variety of nutritional components and contains the function of anticoagulantion,anti-hyperlipidemia,antioxidation and immunity enhancement.The resources of seaweed is rich in Fujian province but because of the lag of development and utilization,seaweed processing is at a relative low level.So the deep processing level and utilization rate of seaweed need to be improved.In this study,suitable raw materials for processing seaweed have been selected and a set of calcium salt crispness-keeping and biological fermented deodorization technology have been developed to solve the problem of seaweed odor and fragility in processing.A compound beverage of seaweed and soybean milk was invented,which contained the nutrition of both marine plants and land plants and had good flavor and chewing feeling of seaweed granules..The results of the study were as follows:1.Aiming at the deodorizing effect and texture quality of special seaweed,seaweed materials that was suitable for making seaweed compound plant beverage were screened.The results showed that after using the new technology of crispness-keeping,fermentation,and deodorization,the color of Saccharina japonica(kelp)was maintained and the seaweed odor was removed,the tight tissue and crisp texture were maitained,so the highest sensory scores were got by this kind of seaweed so kelp was selected for the most suitable the raw material of seaweed beverage.In contrast,the color of Gracilaria lemaneiformis and Bangia fusco-purpurea were easy to fade and the seaweed ordor were not removed completely.The texture was soft and sticky so the chewing feeling was bad.2.A comprehensive method for evaluating the quality and texture of the seaweed was established by principal component analysis method.Using the texture composite index as the indicator,the optimum formula of crispness-keeping was obtained by single factor and response surface method:blanching time 4.77 min,CaCl2 mass concentration 1.54 g/L,and blanching temperature 87.8?.Under this condition,the kelp texture composite index was 75.21 ±0.02.The changes of the water distribution and structure of the kelp before and after the crispness-keeping were studied by low field NMR and scanning electron microscope.The results showed that after blanching and crisp-keeping,migration of the water in kelp was from free water to bound water,and the water holding capacity of kelp was better.The structure was more compact and the cell gap was smaller.3.Using yeasts and lactic acid bacteria as fermentation strain,mixed strains with good deodorization effect were screened by sensory evaluation methods.Saccharomyces cerevisiae J4 and Lactobacillus paracasei subsp.paracasei R37 could give the fermented kelp unique flavor.Using the comprehensive score of the deodorization index and the texture composite index weighted by 8:2 as the synthesis index,the optimum formula of fermentation was obtained by single factor and response surface method:fermentation temperature 30?,fermentation time 7.5 d,inoculation amount of mixed strains 9%(v/w),and the strain ratio(R37/J4)2:1,Under this condition,the comprehensive score was 94.05±0.37.Flavor compounds were identified by headspace solid phase microextraction and gas chromatography-mass spectrometry.1,3-octadiene,E,Z-3-ethylidenecyclohexene 1-nonanol,1-heptanal,1-iodooctane and other volatile flavor compounds played a major role in the seaweed smell,and their relative content decreased or were even not detected after fermentation.It produced ?-phenylethanol,peach aldehyde,ethyl tetradecanoate,octanoic acid,E-2-nonenal-l-ol and others which contributed to the fermented flavors of kelp.4.The optimum condition of deodorization for soybean milk was obtained by lye soaking technology:soybean soaking temperature 80?,soaking liquid pH 9 and soaking time 60 min.Under these conditions,protein utilization rate was higher than 90%,and lipoxygenase activity was less than 300 U/g.And sensory score were selected as indicators,the optimum stabilizer combination of seaweed beverage was obtained by orthogonal test and variance analysis:The content of compound emulsifier 0.30%(w/v),xanthan gum 0.10%(w/v)and CMC 0.15%(w/v).A new product with strong flavour of soybean milk and seaweed was invented.The texture of seaweed granules and the chewing feeling was good.All physicochemical indicators could still meet the requirements of the national standard GB 30885-2014,which was for vegetable protein beverage.