Study On The Fermentation Process Of Niacin-Rich Citrus Powder

This article takes valuable second and unmarketing fresh citrus as main material,combining with efficient processing technology of juice composite enzyme, using of high-yielding niacin microbial strains to ferment orange powder with abundant natural niacin.Cellulose and Acidic pectinase can hydrolysis cellulose and pectin of citrus juice efficiently, so as to improve citrus give juice rate.Only using cellulase can not improve the juice rate effectively,pectinase can improve the rate of15%or more, Through the orthogonal test L16(4)5of substitutability of the two enzymes、pH、zymolysing temperature、 zymolysing time,can can make the juice rate increased by20%or more.For the sake of seed cultivation optimization and wave bottles of cultivating optimization,we choose the Salt-tolerant increase incense yeast that of oil-rich nicotinic acid as a original strain. After optimization fermentation, the content of reducing sugar in orange juice can be added to 10%, adding amount of nitrogen source for2.5%, and the proportion of yeast creams and (NH4)H2PO4is2:0.5, KH2PO4and MgSO4for1.0%and0.1%respectively. By comparison of the matched group, maximum contentof nicotinic acid is26.34mg/100mL, which is Increased44.33%. On this basis add metabolic accelerant tryptophan VB1、 VB2, can make nicotinic acid content of28.51mg/100mL, and make nicotinic acid content of28.51mg/100mL.Combine the fermentation tank structure parameter and fermentation process parameters,we maked a comparison of enlarge fermentation dynamics curve with5L、100L and1000Lfermenter.In these three fermentation process,the maximum yield of nicotinic acid are24.85mg/100mL、23.6mg/100mL and21.61mg/100mL respectively. Then, on the basis of growth kinetics of microbial, the equations for discribing microbial growth, nutrient consumption and metabolites production are presented. using equation of Logistic、Luedeking-Piret and Luedeking-Piret-Like. Test of Goodness for fit are0.9815、0.9789、0.9879。 They can characterize the fermentation process of nicotinic acid well, that can be applied to enlarge the actual production of fermentation, to fill material partial fermentation provide theoretical foundation. The model of experiment in1000L fermentation tank shows that basic values can achieve the expected effect. By single factor and orthogonal test draw the zymolysing optimal conditions of naringinase are:pH4.2, enzyme solution temperature45℃, enzyme solution time50min, enzyme dosage0.005g/100mL. This technology can remore off bitter to61.75%. Through the analysis of variance that adding0.5%β-cyclodextrin which can embedd bitterness substances basic can eliminate bitter taste, the effect is well. After spray drying, the content of nicotinic acid in orange powder is about250mg/100g. Combined with the actual process route this product, through analysis of costs, orange powder is about2.2million yuan per ton.