The Tropical Products Institute

In nearby Gray’s Inn Road, opposite Gray’s Inn itself, stands a recently refurbished building that once housed the laboratories of the Tropical Products Institute (TPI).

TPI originated as the Scientific and Technical Department (later the Colonial Products Laboratory) of the Imperial Institute, a celebration of Empire opened in Kensington by Queen Victoria in 1893. The magnificent buildings of the Imperial Institute were demolished in the 1950s to make room for the expansion of Imperial College, although an original tower, known as the Queen’s Tower, still survives. With the end of Empire and changing attitudes towards international development, TPI was established in Gray’s Inn Road in 1957 with the brief to conduct research, development and advisory work to help developing countries derive greater benefit, post-harvest, from their renewable resources.

Over the years, TPI worked in areas as diverse as fish processing, essential oil production, paper making, copra processing and insect pheromones and conducted market surveys, field studies and pilot trials around the globe. The importance of microorganisms in post-harvest agriculture for both good and ill quickly led to microbiological questions becoming an important aspect of TPI’s work.

In the Spring of 1960, a mysterious new disease was identified on English poultry farms, affecting young turkeys in particular. Described as turkey ‘X’ disease, more than 500 outbreaks were reported between May and August. These centred mainly on farms in the southeast of England and caused the death of 100,000 turkeys, with heaviest losses among those around 1 month old. Teams from a number of agencies, including TPI, failed to identify any known bacterial or viral pathogen and attention eventually turned to peanut meal, which had been used as a protein source in a pelleted feed used on affected farms. This had been imported from Brazil where conditions of storage had allowed the mould Aspergillus flavus to grow on the peanuts, producing the potent toxic and carcinogenic secondary metabolites now known as aflatoxins. It was at TPI that the responsible A. flavus was first identified and that methods of aflatoxin analysis were developed, based on their separation by thin layer chromatography and detection by the intense fluorescence they produce under short-wave UV light. Dr Philip Spensley, who later became a Director of TPI, apparently coined the name ‘aflatoxin’.

Turkey ‘X’ disease subsided rapidly with the end of the turkey hatching season in the late summer but a major new hazard to both animal and human health had been discovered, and international concern about mycotoxins in food and feed burgeoned. To this day they remain a major challenge wherever safe storage of dried commodities can be a problem. In the years that followed, important work on mycotoxins continued at TPI with, for example, the first structure determination of rubratoxin (by a noted SfAM member, Maurice Moss, and colleagues) and numerous projects with very practical concerns such as safe crop storage, sampling plans, detection and detoxification.

With government economic cutbacks from around 1980, TPI went through a long period of retrenchment, contracting and amalgamating with other government-run scientific units working in related fields such as the Centre for Overseas Pest Research. It finally left Gray’s Inn Road in 1988 and today its successor, the Natural Resources Institute (NRI), is based in Chatham as part of the University of Greenwich. No longer a government unit, its activities are funded by a range of national and multinational agencies and it retains an active interest in food microbiology, contributing two speakers to the 2015 SfAM Summer Conference programme on fermented foods.

It might also be worth a passing mention that TPI was the home (at different times) of two later Presidents of SfAM – Professor Basil Jarvis and myself. During his time at TPI, Basil Jarvis worked on mycotoxins other than aflatoxin, such as rubratoxin. Regrettably I can make no claim to having made any seminal contributions to our knowledge of mycotoxins. Some might say my most noteworthy achievement was running the TPI’s 5-a-side football team, which for several years graced the Finsbury Leisure Centre lunchtime league. It is perhaps misleading to suggest that the team was an asset to the league, noted as we were compensating for a distinct lack of skill with a dour negativity, which one season saw us earn points from 11 goalless draws out of 20 matches – we lost the others. In the laboratory, my time was spent largely on fermentation projects such as vinegar production from materials such as export reject bananas, cashew apples, pineapple juice and cocoa sweatings, and the preservation of fish by lactic acid fermentation. A distinct problem with the latter work was that, ever a martyr to scientific rigour, I felt compelled to include untreated controls in all experiments. In time, these would become such noisome examples of piscine putrefaction they were capable of disabling passengers on the upper deck of passing buses. I’m sure this will resonate with my former colleagues at TPI for whom the memory doubtless lingers on, rather like the smell.