Study On The Preparation Process Of Oat Milk And Its Shelf Life

Oats,as an advantageous plant resource in Inner Mongolia,is a "therapeutic" crop with high nutritional value and unique flavor,which is an ideal raw material for the preparation of plant-based cereal beverages.Therefore,this study was conducted to select the best heat treatment method for oats,to explore and optimize the enzymatic process of oat milk and its formulation process,and to determine the shelf life of the finished oat milk.The specific results of the study are as follows:(1)To investigate the effects of three different heat treatment methods,namely,atmospheric pressure steaming,microwave and frying,on oat milk.The results showed that the lipase activity of oat seeds under the atmospheric steaming method was 74.5μmo L,the β-glucan content was 4.7%,the centrifugal sedimentation rate of oat milk was12.7%,and the color and stability had obvious advantages compared with the other two heat treatment methods,and after comprehensive consideration,the atmospheric steaming method was chosen for the heat treatment of oat milk to inactivate the enzyme.(2)The enzymatic digestion process of oat milk was optimized by single-factor and orthogonal tests.It was found that the best process condition for liquefaction was to use medium temperature α-amylase at p H 6.0,enzymatic digestion temperature of 60°C and enzyme addition of 0.15% for 60 min;the best process condition for saccharification was to use saccharifying enzyme at p H 4.5,enzymatic digestion temperature of 60°C and enzyme addition of 0.15% for 90 min,under which the obtained The DE value of oat milk obtained under this condition was the highest,46.91%,with the greatest degree of starch hydrolysis and the most amount of reducing sugar production.The formulation of oat milk was optimized by single-factor and response surface tests.It was found that the optimal formulation conditions were 6.5% xylitol addition,0.09% edible salt addition and0.14% xanthan gum addition,when the oat milk was smooth and creamy.(3)The optimum process parameters of oat milk: oats and water were pulped at a ratio of 1:15 after steaming at atmospheric pressure,0.15% medium temperature α-amylase was reacted at 60°C for 60 min,and then 0.15% saccharase was reacted at 60°C for 90 min.6.5% xylitol,0.09% edible salt and 0.14% xanthan gum were added to the oat milk.The oat milk was homogenized twice at 50 ℃,40 MPa and 60 MPa,and sterilized at 90 ℃ for 10 min.The sensory score of the oat milk obtained under this condition was84 points,and the aroma of oat milk was harmonized with unique flavor,silky and smooth with oat fragrance.(4)The results of the oat milk shelf-life test showed that the soluble solids content of oat milk decreased under low temperature(4°C)and room temperature(25°C)conditions,from 6.8% to 5.4% at 9 d under room temperature conditions;and from 6.8% to 5.6% at12 d under low temperature conditions.During the storage period,the centrifugal sedimentation rate of oat milk increased,the liquid was unstable,the color changed from creamy white to dark yellow,and the microbial indexes exceeded the national standards.Based on its sensory evaluation,emulsion stability,and tissue state,the shelf life of the oat milk products in this study was determined to be 12 d at 4°C and 9 d at 25°C.Compared with the oat milk without any treatment for 3 d,the shelf life was effectively The shelf life of the oat milk products in this study was determined to be 12 d at 4°C and9 d at 25°C.The shelf life of the oat milk products in this study was extended compared to 3 d without any treatment.