Bottle Material and Cleansing Procedures of Infant Feeding Bottles.

The cleanliness of feeding bottles is vital for child health. Although machine cleansing of bottles in the food industry has been established, mechanical and manual cleansing methods are highly variable. This study was undertaken to determine the differences in the cleanliness of bottles that were cleaned using various combinations of bottle materials [glass and polypropylene (PP)], rinsing water volumes (1/3, 1/2, and 2/3 capacity of a bottle), and sustained shaking times (5 seconds and 20 seconds). Total organic carbon (TOC) and conductivity measurements were respectively used to evaluate the rinsed quantities of organic and inorganic formula residue from feeding bottles. The results indicated that glass bottles filled with rinsing water to 2/3 of their capacity showed the most efficient cleansing performance. However, the PP bottles exhibited a relatively poor cleansing result, particularly for organic cleanliness. The organic residue tends to accumulate on the PP bottle interior because of the aggregation of compounds with similar properties. The shaking time hardly influenced the cleanliness. The glass bottle was superior to the PP bottle in both organic and inorganic cleanliness, and organic constituents were more difficult to rinse from the bottle than the inorganic constituents were.