Study On The Stability Of Niacin/nicotinamide In Infant Formula

This paper discusses the factors affecting the stability of niacin and nicotinamide,such as light,temperature,pH,oxidants,oxidants,metal ions,and further investigates the loss caused by the initial addition of niacin and nicotinamide in each process of wet production,which constitutes a systematic study of the stability of niacin and nicotinamide in infant formula from part to whole,And the future research direction is prospected.Taking niacin and nicotinamide in infant formula milk powder as the research object,the detection method of niacin and nicotinamide in infant formula milk powder is optimized,and the saponification step in the national standard method is improved.The overall method has the advantages of simple operation,short detection time and accurate results.It is suitable for the determination of niacin and nicotinamide in infant formula milk powder at all stages and milk powder products of other people.At the same time,the stability changes of niacin and nicotinamide components of milk powder during different production processes and storage environments under different raw material formulations were studied.The study summarized the production process,storage environment and the fluctuation law of niacin and nicotinamide content in packaging materials of infant formula milk powder,analyzed the effects of light,temperature,moisture,acid-base,metal ions and other factors on the stability of niacin and nicotinamide,and completed the following research work:(1)This study improved the HPLC method for the determination of niacin and nicotinamide in infant formula milk powder.Lipase,alkaline solution and ethanol solution are added to the milk powder.The sample is hydrolyzed at high temperature in dilute acid and then sent to high performance liquid chromatograph for detection after constant volume.The overall chromatographic peak shape is sharp and symmetrical,the resolution is high,the response value is strong,and the retention time has good repeatability.The precision RSD(n=6)is 0.840%～4.32%,the recovery range is 94.6%～104%,and the detection limit of niacin is 0.24 mg·kg-1 and nicotinamide is 0.25 mg· kg-1.This method is simple and accurate for the determination of niacin and nicotinamide in infant formula milk powder,which can meet the standard requirements of the test.(2)The stability of nicotinic acid and nicotinamide fortifier was studied experimentally.Through the changes of light,temperature,metal ions,acid-base and other factors,the content fluctuation law of nicotinic acid and nicotinamide under different conditions was determined and summarized.The results show that the stability of nicotinic acid and nicotinamide fortifier is greatly affected by light,temperature and acid-base conditions,while oxidants and metal ions have little effect on its content.The maximum loss rates caused by light,temperature,oxidant,acid and alkaline conditions were 64.7%,72.3%,72.1%,75.8%and 79.3%,respectively.The loss rates caused by some metal ions were 21.3%.(3)The stability changes of niacin and nicotinamide in the production of infant formula milk powder were studied and summarized.The process of homogenization,sterilization and spray drying in the production of milk powder was simulated,and the change rule of nicotinic acid and nicotinamide content before and after each process was determined and summarized.The results showed that the sterilization process had the most obvious effect on the stability of nicotinic acid and nicotinamide in the processing and production process of milk powder,and its loss rate was 12.73%;The loss rate of niacin and nicotinamide during homogenization was 6.64%,which was relatively low;The loss rate of nicotinic acid and nicotinamide was 2.52%during spray drying.The loss rate of nicotinic acid and nicotinamide caused by fluidized bed drying process is 4.02%;The data results of the concentration process fluctuate greatly and are not representative.After the whole processing process,the loss rate of niacin and nicotinamide in milk powder can reach 25.9%.(4)The factors affecting the storage stability of niacin and nicotinamide in infant formula powder were investigated through various experiments.The results showed that light had a significant effect on niacin and nicotinamide in infant formula powder;It can be seen that the preparation temperature of nicotinamide has a great effect on the stability of nicotinamide powder after high temperature storage;High humidity conditions will cause moisture absorption and easy hardening of samples.It is very important to control humidity during storage.Packaging is also an important factor affecting stability.After six months of accelerated test,the average preservation rate of canned and boxed is about 88.9%and 84.8%,which are higher than the nutritional labeling value of the sample.The canned container has good sealing performance,and nitrogen filling in the production process makes its stability better than that in bags.In the normal temperature experiment,it can be seen that the stability of nicotinic acid and nicotinamide is good.It simulates the normal use process after opening.During the consumption cycle,all indexes of infant formula milk powder are stable.