JournalofApplied Bacteriology 1978, 45, 3 17-320

0 b i tua ry

Maurice Ingram, c.B.E., M.A.,P~.D.. D.v.M., F.I.Biol., F.I.F.S.T.

With the sudden death of Maurice Ingram at his home in Churchill, Avon, on Tuesday 15 November, 1977, the Society for Applied Bacteriology lost one of its most loyal supporters and food microbiologists throughout the world one of their most distin- guished colleagues.

Dr Ingram, who was born in Bradford, Yorkshire, in 1912, was educated at Bradford Grammar School and did so well there that he was awarded a State Scholarship and an Entrance Scholarship to Queens’ College, University of Cambridge. He was a brilliant scholar, obtaining a First Class in both Part I (Chemistry, Physics, Botany and Mathematics) and Part I1 (Botany) of the Natural Science Tripos. But for an untimely injury he would almost certainly have represented the University at soccer. After graduating in 1933 he commenced work at the Low Temperature Research Station for Research in Biochemistry and Biophysics, Cambridge and in 1937 obtained his Ph.D. for a dissertation on ‘The Effect of Salts on Bacterial Respiration’. For the next 30 years he continued his close association with Cambridge University, supervising students and participating in various activities and expeditions, many of which were associated with the Botany School.

His early research on bacterial growth and metabolism led to studies of the influence of pre- and post-slaughter stress in pigs on the bacteriological quality and stability of the products after the meat was cured. This in turn led to an interest in the halophilic micro- flora of curing brines. His research became particularly significant during the Second World War when he was engaged in judging the edibility of imported meat delayed by or salvaged after enemy action. In addition he was concerned in the development of compact military rations from dehydrated foods, and was responsible for designing and getting into factory production about half the items in the standard British 24 h ration issued to Allied armies and to underground organizations in Europe. He later received the Haakon VII Liberty Medal from the Norwegian Government for his contribution to the operation which destroyed the heavy water plant at Rjukan.

His experience during and immediately after the war gave him an interest in many different aspects of food spoilage and preservation. Work for the Ministry of Food on yeast spoilage of concentrated orange juice took him in an advisory capacity to manufacturers in Israel, Italy and Spain, and gave him a continuing interest in yeasts, particularly osmophilic ones. His book, A n Introduction to the Biology of Yeasts was published in 1955. The use of sulphur dioxide for preserving the orange juice led to basic studies on the mode of action of chemical preservatives which were subsequently extended to antibiotics for preserving foods and the problems of antibiotic resistant floras. With the formation of a radiation section in 1950 to study the use of irradiation for the sterilization or pasteurization of foods his interest was widened to include factors affecting the radiation resistance of clostridia and other organisms.

Immediately after the war when food was in short supply he was also concerned with studies of whalemeat for human consumption. Investigations were carried out in Norway and the Low Temperature Research Station also sent teams to the Antarctic on two occasions. His observations (Robinson et al. 1953) on the involvement of both clostridia and faecal streptococci in the deep spoilage of whalemeat led to a continuing

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interest in the role of the intestinal flora in the spoilage of raw and cured meats, the origin of the organisms present and, in the case of the faecal streptococci, the differentiation of strains of human or animal origin, and their use as indicators of faecal contamination.

The observation that clostridial multiplication in the deep muscle tissues of the whale did not occur until after the onset of rigor, whether this occurred in 2 h or 15 h, led to further studies of factors, especially Eh, affecting the incidence and growthlof clostridia particularly Clostridium perfringens in the deep muscle tissue of meat carcasses. Subsequently this work was extended to considerations of factors such as pH, nitrite and salt in the control of Clostridium botulinum in cured meats, particularly pork.

In 195 1 Dr Ingram became Head of the Microbiology Department with the broad responsibility for all microbiological work at the Low Temprature Research Station and subsequently in 1958 also took charge of the Radiation Section. In the reorganization in I95 1 he changed microbiology from the commodity-based servicing unit it had become during the war and concentrated on studying the basic principles governing food spoilage such as temperature, pH, water activity or gaseous environment and preservation whether this was by heat, irradiation or the use of chemical preservatives or antibiotics. He was a creative thinker rather than a bench worker (despite an interest in gadgets, and considerable manual manipulative ability) and collected around him a team of research workers individually specializing in the many different aspects of food microbiology (B. P. Eddy, E. M. Barnes, J. A. Barnett, A. G. Kitchell, M. J. Thornley and T. A. Roberts arrived in that order). Overseas visitors were always welcome for long or short stays and made a significant contribution to the research work of the department. His ability to develop and co-ordinate ideas led to the publication of many carefully thought out papers only a few of which are mentioned below.

Throughout his life he retained his interest in mathematics and statistics and whilst in Cambridge often accepted Diploma in Statistics students for microbiology projects. This led to several studies concerning the accuracy of various counting techniques and best methods for selecting representative colonies for further identification. Unfortu- nately many of the results were not published or alternatively they were buried in the most unlikely papers. For example, the method he developed for calculating the numbers of organisms present in the sample from the colony counts at different dilutions, which is known as the ‘Weighted Average’, is contained in a paper on the survival of Bacillus subtilis spores in the baking of bread (Farmiloe et al. 1954) and is only now being adopted in official standard methods.

In 1963 Dr Ingram was appointed first Director of the projected Meat Research Institute then still in Cambridge and in 1965 the last director of the LTRS. He moved with his staff to the new Institute in Langford, Bristol in 1968, while the rest of the Low Temperature Research Station staff moved to the new Food Research Institute in Norwich in the same year. Dr Ingram remained Director of MRI until 1973 and was also Professor of Applied Microbiology in the University of Bristol. After his retirement at the age of 61 he was once more able to concentrate on his scientific activities rather than the ever increasing load of administration which he did not really enjoy.

Although many would consider him a reserved man, he had a mischievous sense of humour and he firmly believed in the need to discuss and communicate ideas, both at the national and international level. He was an active member of a number of Scientific Societies including the Society for General Microbiology, the Society of Chemical

OBITUARY 3 19

Industry and the Institute of Food Science and Technology of which he was a Fellow, but it was probably in the Society for Applied Bacteriology that he felt most at home. He joined in 1949 at a time when traditional agricultural and dairying microbiology was being broadened to include other foods and the Society itself was widening its interest to include many different aspects of applied microbiology. He immediately gave his support to the organization and running of the Symposia on special topics which have now become so much a feature of the Society’s meetings, often being one of the main contributors. He was a Committee member from 1952-55 and President from 1956- 58. He later became a Trustee and served in this capacity until his death. He attended meetings regularly and unstintingly gave much of his time to the affairs of the Society as well as encouraging his staff to become actively involved. When he took the Chair at a meeting one could be sure that the proceedings would never be dull. He was not afraid to express his views and could be devastatingly critical at times. On the other hand, one of his greatest virtues was that he would freely admit if he was wrong.

In 1953 together with Dr R. Buttiaux, Dr D. A. A. Mossel and others he pioneered the formation of the Food Microbiology and Hygiene Section of the IAMS and became its first President, a position which he held until 1968. He presided over and contributed to a number of the Symposia organized by the Section on a wide variety of topics the first being held in Lille, France, in 1954, on the ‘Bacteriology of Semi-preserved Meats’. He participated in the formation of the International Commission for Microbiological Specifications of Foods (ICMSF) which originated as part of the Food Microbiology and Hygiene Section in 1962. The ICMSF has already published two books which are important guide-lines for food microbiologists, the second, Micro-organisms in Foods: 2 Sampling for Microbiological Analysis: Principles and Specific Applications 1974, ICMSF, University of Toronto Press, was one with which Dr Ingram with his statistical interest was particularly concerned. At the time of his death he was involved in the writing of the third book Micro-organisms in Foods: Microbial Ecology and Spoilage.

He had a good knowledge of languages and was perhaps at his best when presiding over the smaller international meetings. Many of our overseas colleagues remember with gratitude his patience with their hesitant English and the help he often gave them over the scientific papers they were preparing for publication in books or journals where English was the required language. On a number of occasions he served on Expert Advisory Panels for FAO, WHO and the International Atomic Energy Agency.

He was an excellent teacher and often participated in the WHO course on food microbiology held annually at the Institute Pasteur, Lille, France. He was particularly glad to co-operate in the institution of the biennial 3 week advanced course in food microbiology which held its first meeting in 1973 at the University of Surrey and since then in 1975 and 1977 and has been attended by people from many parts of the world. As Chairman of the Organizing Committee he played a very active part in the actual running of the course going into residence with the students for a high proportion of time, giving some of the basic lectures, assisting in practical classes and generally participating in discussions.

He was a man of wide interests and ability and was endowed with a remarkable memory. Apart from his profession of microbiologist he was also a botanist, master beekeeper, amateur astronomer, motor mechanic, litterateur, pianist and an enthusiastic sportsman. Colleagues and friends throughout the world will remember him and his wife

3 20 OBITUARY

Joyce for their generous hospitality and friendship. He was awarded the CBE in 1974 and a n honorary degree of Doctor of Veterinary Medicine was conferred on him by the Ludwig Maximilians University of Munich in the same year. In September 1977 he received the Polish Society of Microbiology Gold-Medal of Honour for ‘most out- standing services t o microbiology’-a fitting tribute t o a scientist of distinction and a man of great personal achievement and integrity.

A full list of Dr Ingram’s publications, of which there are more than 200, is deposited with the Society archivist but can also be obtained from the A.R.C. Meat Research Institute, Langford, Bristol, BS18 7DY. A selection of his papers which illustrates the breadth of his interests is listed below.

ELLA M. BARNES Selected Publications

FARMILOE, F. J., CORNFORD, S. J., COPPOCK, J. B. M. & INGRAM, M. 1954 The survival of Bacillus subtilis spores in the baking of bread. Journal of the Science of Food and Agriculture 6,292-304.

INGRAM, M. 1951 The effect of cold on microorganisms in relation to food. Proceedings of the Society for Applied Bacteriology 14,243-260.

INGRAM, M. 1957 Microorganisms resisting high concentrations of sugars and salts. In Microbial Ecology ed. Williams, R. E. 0. & Spicer, C. C. pp. 90-133. The 7th Symposium of the Society for General Microbiology, Cambridge, Cambridge University Press.

INGRAM, M. 1962 Microbiological principles in prepacking meats. Journal of Applied Bacteriology 25,259-281.

INGRAM, M. 1962 I. Post mortem changes in redox potential and pH of meat. 11. The importance of redox potential in the microbiology of meat. 111. The importance of pH in the microbiology of meat. Supplement to Medlemsblad for Den Norske Veterinaerforening 14,

INGRAM, M. 1969 Spore-formers as food spoilage organisms. In The Bacterial Spore ed. Gould, G. W. & Hurst, A. pp. 549-610, London: Academic Press.

INGRAM, M. 1971 Microbiological standards for foods. FoodZndustries of South Africa 24,8-9, 11 & 13.

INGRAM, M. 1971 The Microbiology of Food Pasteurization. SIK Rapport No. 292, AI-A44 ‘Pastorisering AV Livsmedel’.

INGRAM, M. 1976. The microbiological role of nitrite in meat products. In Microbiology in Agriculture, Fisheries and Food eds. Skinner, F. A. and Carr, J. G. pp. 1-18. Society for Applied Bacteriology Symposium Series No. 4. London: Academic Press.

TNGRAM, M., BUTTIAUX, R. & MOSSEL, D. A. A. 1964 General microbiological considerations in the choice of anti microbial food preservatives. In Microbial Inhibitors in Food pp. 38 1-392. 4th International Symposium on Food Microbiology, SlK, Goteborg, Sweden. Stockholm: Almquist & Wiksell.

INGRAM, M. & ROBERTS, T. A. 1966 Microbiological principles in food irradiation. Proceedings of Symposium on Food Zrradiation pp. 267-285. Karlsruhe June 1966. Vienna: Inter- national Atomic Energy Agency.

INGRAM, M. & ROBERTS, T. A. 1971 Application of the ‘D-concept’ to heat treatments involving curing salts. Journal of Food Technology 6,2 1-28.

INGRAM, M. & ROBERTS, T. A. 1976 The microbiology of the red meat carcass and the slaughter- house. Royal Society of Health Journal 96, 270-216.

INGRAM, M. & FARKAS, J. 1977 Microbiology of foods pasteurised by ionising radiation. Acta Alimentaria 6, 123-185.

MOSSEL, D. A. A. & INGRAM, M. 1955 The physiology of the microbial spoilage of foods. Journal ofApplied Bacteriology 18,232-268.

ROBINSON, R. H. M., INGRAM, M., CASE, R. A. M., BENSTEAD, J. G. & DANIELS, H. E. 1953 Whalemeat: Bacteriology and Hygiene. Special Report No. 59 Food Investigation Board, D.S.I.R. London: H.M.S.O.

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