Research And Development Of Hemp Fermented Milk

Hemp seeds are rich in a good proportion of amino acids,high proportion of unsaturated fatty acids,and the proportion of polyunsaturated and monounsaturated fatty acids meets the needs of the hemp kernel oil,rich in phenols and vitamins,and rich in volatility substances and lignans etc,therefore,it plays a significant role in physiological activity.Lactobacillus fermented food can improve the intestinal microecological balance by inhibiting intestinal pathogens and metabolizing short-chain fatty acids.Lactic acid bacteria fermented hemp milk has good laxative function,In this experiment,lactic acid bacteria fermented with hemp milk was used to screen out lactic acid bacteria with strong ability to inhibit intestinal pathogens and produce short-chain fatty acids.The influence of milk stability,and the fermentation conditions of hemp fermented milk were optimized.Below are key research findings:(1)Effects of different lactic acid bacteria fermentation on bacteriostatic ability and short chain fatty acid production of hemp-fermented milk.Methods:38 strains of Lactobacillus isolated from the laboratory and 1 strain of Streptococcus thermophilus grx90 were mixed and fermented with hemp milk at a ratio of 5:1 to study the effects on sensory evaluation,the basic fermentation conditions are fixed as follows:full fat milk 12%,hemp pulp addition 20%,sugar addition 6%,homogenization pressure 20 MPa,heat treatment conditions 80? 20 min and fermentation temperature 42?,bacteriostatic ability and short chain fatty acid production of hemp fermented milk.The results showed that the sensory scores of hemp milk mixed with 10 strains of 74,R26,1301,113,LV108,grx19,71,118,4 and grx10 and Streptococcus thermophilus grx90 were higher,and all were greater than 84.The fermented hemp milk mixed with strain 71 and cocci grx90,had a significantly higher inhibitory ability against Staphylococcus aureus than other strain combinations(p<0.05),and the diameter of the inhibition circle was 23 mm;the inhibitory ability of strains 74 and 71 are mixed with cocci grx90 to ferment hemp fermented milk against Salmonella Significantly higher than other strain combinations(p<0.05),the diameter of the inhibition zone was 23 mm and 22 mm respectively;the inhibitory ability of strains 71 and 1301 mixed with cocci grx90 to ferment hemp fermented milk against Bacillus subtilis was significantly higher than other strain combinations(p<0.05)The diameters are 21.7 mm and 20.7 mm,respectively;the inhibitory ability of strain 1301 mixed with cocci grx90 to ferment hemp fermented milk against Pseudomonas is significantly higher than that of other strain combinations(p<0.05),and the diameter of the inhibition zone is 28.3 mm;The ability was significantly higher than that of other strain combinations(p<0.05),and the diameter of the zone of inhibition was 26 mm.24.3 mm and 24.3 mm,respectively.Strain 71 mixed with cocci garx90 to ferment hemp fermented milk inhibited Bacillus cereus significantly higher than other strain combinations(p<0.05),with an inhibition zone diameter of 22.7 mm.The ability of strains 74 and 71 mixed with cocci grx90 to ferment hemp fermented milk to produce acetic acid was significantly higher than that of other strain combinations(p<0.05),with contents of 1.611 mg/mL and 0.308 mg/mL,respectively.Only strain 74 mixed with cocci grx90 to ferment hemp fermented milk produced propionic acid at a content of 0.039 mg/mL.The ability of strain 74 mixed with cocci grx90 to ferment hemp fermented milk to produce butyric acid was significantly higher than that of other strain combinations(p<0.05),and the content was 0.562 mg/mL.The content of isobutyric acid produced by strain 74 mixed with cocci grx90 to ferment hemp fermented milk was significantly higher than that of other strain combinations(p<0.05),and the content was 0.022 mg/mL.The content of valeric acid produced by strain 74 mixed with cocci grx90 to ferment hemp fermented milk was 0.027 mg/mL.Strains 74 and 1301 mixed with cocci grx90 to ferment hemp fermented milk had a strong ability to produce isovaleric acid,and their contents were 0.054 mg/mL and 0.05 mg/mL,respectively.Based on the combination of different strains' bacteriostatic ability and short-chain fatty acid production ability,strains 71,74 and 1301 were selected for the next test.(2)The effects of different pretreatment methods of hemp seed,the amount of hemp slurry added and the heat treatment conditions of hemp milk on the stability of hemp fermented milk.Methods:Single factor and orthogonal experiments were carried out to study the effects of ultrasonic,microwave and water extraction methods of hemp seed pretreatment,the amount of hemp pulp and heat treatment conditions on the stability of hemp milk fermented by strains 71.74 and 1301 and grx90 respectively.The results showed that the centrifugal sedimentation rate of mixed fermented hemp milk with strains 71 and grx90,74 and grx90 and 1301 and grx90 was increased from 48.43%,49.17%and 47.13%before treatment to 53.57%,54.77%and 52.37%;While microwave optimization will increase the centrifugal sedimentation rate of hemp milk from 50.4%,50%and 50.3%before treatment to 54%,54.43%and 54.4%respectively;while water extraction optimization will centrifuge the hemp milk The precipitation rate increased from 46.83%,46.1%and 47.1%before treatment to 56.73%,57.45%and 55.53%,respectively.Through the orthogonal test,it was found that the best treatment method for the combination of the three groups of strains was A1B3C1,that is,the pretreatment method of hemp seed was microwave,the heat treatment condition was 90? for 10 min,the addition amount of hemp was 10%,and the centrifugal precipitation rates were 62.03%,62.49%and 62.26%.(3)Optimization of hemp fermented milk process.Methods:After two or three or three and three equal ratios of strains 71,74 and 1301,mixed with S.thermophilus grx90 to ferment hemp milk at a ratio of 5:1,through a single factor test,in different strain combinations,when strains 71 and 74 mixed with grx90 fermented hemp milk,the centrifugal sedimentation rate and sensory score of fermented milk are higher,62.3%and 85.3 points respectively;in different fermentation time,when the fermentation time is 6 h,the centrifugal precipitation rate and sensory score higher,62.3%and 86.7 points respectively;in different ratios of bacilli,when the ratio of bacilli is 5:1,the centrifugal sedimentation rate is higher,62.3%,when the ratio of bacilli is 3:1,the The sensory score is higher,at 87.7 points.Through orthogonal experiments,it was found that the optimized fermentation conditions were the combination of strains Lactobacillus 74,1301 and Streptococcus thermophilus grx90,the fermentation time was 6 h and the ratio of Corynebacterium was 1:1:2,and the centrifugal precipitation rate was verified as 71.2%and the sensory score is 89 points.