PULLULAN, an "Edible” or "Non-polluting” plastic, was highly anticipated at the initial developmental phase, however, it took 30 years to develop the high demand there is today. Currently, PULLULAN is used in a wide range of products because of its high adhesive property, modifies materials to a desired viscosity, and can be processed into films and capsules.
PULLULAN is a unique product of Hayashibara since it is produced by microbial fermentation, whereas the majority of Hayashibara’s products are produced by the company’s primary expertise, by enzymatic reactions with starch.
This is the story about the development of PULLULAN from the initial concept to the present.
Polysaccharide produced by microorganisms
In addition to its safety as a food, it is decomposed by microorganisms in nature and generates no toxic gas when burned. It is a unique material that can be used in a wide range of fields since PULLULAN has very little impact on the environment compared to standard plastics.
The discovery started with
a "membrane" formed
in a research beaker
One day, by chance, a beaker containing the PULLULAN solution was left overnight uncleaned. A film-like membrane was formed on the inside of the beaker the following day. The staff members were very excited by this accidental discovery that, "A plastic like-substance can be created from starch."
Challenging mass production project
The two most important issues that needed to be considered when developing a commercial scale product are, yield, and product quality. Three researchers in the R & D department teamed up to launch a project to achieve this.
The first step was to find a “colorless” bacterium that efficiently produces PULLULAN. The known filamentous fungus, also called "black yeast", that produced PULLULAN is literally black．The pigment causes the PULLULAN to be black and would require large-scale bleaching equipment in the manufacturing process. Therefore, it was essential that a strain of the fungus be found or developed that has no color.
Tens of thousands of organisms were screened before a pullulan-producing fungal strain was found that produced very low amounts of pigment. Further, various growth culture media were tested. As a result, a starch syrup made from corn was identified to achieve a high yield of 70%. Finally the mass production method was successfully developed.
Okayama Plant II
Because of the fermentation process
the plant and equipment needed to be
built from scratch
While different types of fermenters, degerming equipment, concentrator, and drying methods were studied, the particularly challenging task was to calibrate a concentrator. Due to its increased viscosity during concentration, pullulan solution becomes lumpy in the tank and loses its flowability. Conversely, if the flowability is optimum, the concentration process becomes less efficient.
Relentless trials were conducted involving the concentrator. Both Hayashibara and the concentrator manufacturer were busy trying to optimizing the process.
Finally, the concentration process was successfully calibrated for mass production. The PULLULAN plant was completed in 1976 despite all the challenges. This accomplishment enabled Hayashibara to produce approximately 200 tons per year.
Significant leap by cooperating with an overseas manufacturer
PULLULAN has strong adhesivenessThe completion of the new plant and the subsequent product release attracted great attention like its successful development did in 1973; however, the sales did not meet expectations partly because of the world energy crisis of the 1970s.
Hayashibara continued to put efforts into application development working with external companies and research institutes. In addition, Hayashibara’s salesforce continually promoted PULLULAN to old and new customers. Nevertheless the successful food applications were limited to uses as a binder, glaze for processed marine products, and thickener for dressings and sauces.
The turning point came in 1993 when PULLULAN was displayed at the IFT Food Expo in the United States. One booth staff member, who at the time was working with a Japanese manufacturer of edible film confectionery made from PULLULAN, was committed to explaining the characteristics of PULLULAN while distributing edible film confectionery samples. His sales effort generated a strong lead from a pharmaceutical/food company and resulted in an exclusive supply agreement for use of PULLULAN in a mouth refreshing film application in 1997.
Later in 2000, a major US pharmaceutical company acquired the company and decided to distribute a pocket-sized mouth refreshing film under the company’s brand name. The product was launched in Canada in 2000 and in the United States the following year. The mouth refreshing film became a big hit reaching annual sales of more than several billion yen. After about 30 years since its original development, PULLULAN finally gained international recognition and demand just before the new century.
The mouth refreshing using PULLULANIn addition to its unique properties, PULLULAN gained even more attention, because of the issue of BSE (bovine spongiform encephalopathy) during this same period. The use of bovine-derived gelatin was avoided, whereas plant-derived PULLULAN attracted attention as a safe alternative.
Hayashibara started the joint development of hard PULLULAN capsules with a capsule manufacturer affiliated with the same major pharmaceutical company that launched the mouth refreshing film. In 2002, the capsules were successfully commercialized in Japan.
With this big success of the mouth refreshing film and hard capsules, Hayashibara invested in the expansion of their production facilities that increased its production capacity.
Even when the sales volume was low, Hayashibara was producing PULLULAN to maintain the stable demand due to its unique characteristics compared to other products. After 30 years, Hayashibara was rewarded with a great opportunity, and PULLULAN has became one of Hayashibara’s main products.
Hayashibara believes that PULLULAN can still generate additional new applications in a wider range of areas due to its unique characteristics. Hayashibara continues to explore new possibilities of PULLULAN.