As we know DL-Alanine is a nonessential amino acid, meaning it can be manufactured by the human body, and does not need to be obtained directly through the diet.And even plays a key role in glucose–alanine cycle between tissues and liver.In muscle and other tissues that degrade amino acids for fuel, amino groups are collected in the form of glutamate by transamination.The alanine formed is passed into the blood and transported to the liver. A reverse of the alanine aminotransferase reaction takes place in liver. Pyruvate regenerated forms glucose through gluconeogenesis, which returns to muscle through the circulation system. Glutamate in the liver enters mitochondria and degrades into ammonium ion through the action of glutamate dehydrogenase, which in turn participate in the urea cycle to form urea.

while ,even though there is no need to be obtained directly through the diet,In everyday life we seemingly can't leave it. Becouse DL-Alanine mainly uses in food processing industry as nutrition enriching substance and seasoning. Enhancing effect of chemistry seasoning, improving taste of artificial seasoner and sour odor of organic acid, making salt system effect and quality of alcohol type drink better.
So ,when we eat sth delicious,the DL-Alanine has play a positive role more or less.