Issue link: https://read.dmtmag.com/i/1190334
46 STiR coffee and tea / Issue 6, 2019 (December / January 2020) T Modern tea bagging lines are marvels of ingenuity; compact and complex machines that perform a seemingly simply task Adaptive Bagging ACMA T4 Modula. Photo courtesy ACMA ea bag making and packaging machines are a factory assembly line configured as a compact apparatus. They carry out the complex set of meticulous and demanding functions that take a simple input, a fully processed bulk tea and, increasingly, added herbal and fruit ingredients, and turn it into a simple and conve- nient bag and envelope. The simplicity of input and output obscures just how varied, tailored, flexible, adaptive, fast, accurate, safe, and innovative even tiny functions need to be. These machines are certainly not simple. One example of the importance of a tiny function is the string that connects the tea bag and tag. The traditional thread has been made of nylon and attached to the staple that seals the bag. So simple. But so unacceptable. Consumer pressure, branding, and regulation have all moved against the use of plastics and India's food safety agency has banned staples, an initia- tive likely to be matched by the European Union. The solution is complex. First, the plastic thread has been replaced by organic cotton and biodegradable PLA (polylatic acid) made from biomass waste, such as corn starch. It is very cost-effective but poses technical and chemical challenges, affecting machine design and operation. SoilOn thread is a more recent trademarked extension of PLA bioplastics whose structure has extended the limits on string length from 86 to 170mm. This keeps the tag out of the cup and permits it to be used in tall mugs. As for connecting the string to the bag, air knotting is replacing stapling and me- chanical sewing that require stainless steel needles. Vacuum technology sucks the thread through guidance channels and ties the knot. The overall result is one more contribution to what has become the imperative for tea bag production: environmental as well as product quality. The dominant trend is from plastic to bio, with the nylon (plastic) and PLA (bio) representative instances. Tea bag production has four main assembly line operations. In each of these, there's a wide range of options, all trending strongly to bio. By Peter Keen Gea bag fill and packing machine Staples are out of favor