Page 367 - Demo

SECTION II. APPLIED BIOTECHNOLOGY IN THE PHARMACEUTICAL INDUSTRY... 371The ratio of Lactobacillus brevis bacteria can affect the sensory quality of the product, as this factor can heavily affect the concentration of secondary products and the flavour. Experiments were conducted according to the proposed technological process 2.2.1 with varying Lactobacillus brevis ratios (0%, 5%, 10%, 15%) to evaluate the impact of changing the ratio. The results are presented above.For total acid content, the total acid content is directly proportional to the ratio of bacteria to the raw material, as a higher bacterial ratio leads to more organic acid production reactions: the 10% sample balanced total acid content and sensory quality. The 0% and 5% samples showed lower total acid content, resulting in a less harmonious flavour. The 15% sample had a high total acid content, which could make the taste too sour, reducing the product%u2019s overall quality. In terms of phenolic content, the 5% and 10% samples exhibited higher levels than the 0% sample, likely due to the bacteria%u2019s enzymatic activity%u2014amylase, invertase, and cellulase%u2014that released phenolic compounds by breaking down bonds in complex compounds, causing a decent aroma for the product. However, at the 15% ratio, the phenolic content decreased slightly, potentially due to the small amount of vaporisation or rebinding of phenolic compounds with others.For total liquor colour, the 0% and 5% samples produced the lowest colour intensity, possibly due to fewer phenolic compounds being converted into colour-producing compounds, resulting in a lighter quality and colour for the tea. The 15% sample had the highest colour intensity, causing the tea to appear cloudy and dull, while the 10% sample displayed a harmonious tea colour. The results indicate that the ratio of Lactobacillus brevis (NCTH 24) to the raw material weight affects product quality.