Who Would Have Thought? The Story of a Food Engineer.

Food engineering is a hybrid of food science and an engineering science, like chemical engineering in my particular case, resulting in the application of chemical engineering principles to food systems and their constituents. With the complexity of food and food processing, one generally narrows his or her interests, and my primary interests were in the kinetics of reactions important in foods, thermal processing, deposition of unwanted materials from food onto heated surfaces (fouling), and microwave heat transfer in baking. This review describes how I developed an interest in these topics and the contributions I have hopefully made to understanding food and to the application of engineering.

Feeding the World Today and Tomorrow: The Importance of Food Science and Technology: An IFT Scientific Review.

by Philip E. Nelson, 2007 World Food Prize Laureate; Professor Emeritus, Food Science Dept., Purdue Univ. Just as society has evolved over time, our food system has also evolved over centuries into a global system of immense size and complexity. The commitment of food science and technology professionals to advancing the science of food, ensuring a safe and abundant food supply, and contributing to healthier people everywhere is integral to that evolution. Food scientists and technologists are versatile, interdisciplinary, and collaborative practitioners in a profession at the crossroads of scientific and technological developments. As the food system has drastically changed, from one centered around family food production on individual farms and home food preservation to the modern system of today, most people are not connected to their food nor are they familiar with agricultural production and food manufacturing designed for better food safety and quality. The Institute of Food Technologists-a nonprofit scientific society of individual members engaged in food science, food technology, and related professions in industry, academia, and government-has the mission to advance the science of food and the long-range vision to ensure a safe and abundant food supply contributing to healthier people everywhere. IFT convened a task force and called on contributing authors to develop this scientific review to inform the general public about the importance and benefits of food science and technology in IFT's efforts to feed a growing world. The main objective of this review is to serve as a foundational resource for public outreach and education and to address misperceptions and misinformation about processed foods. The intended audience includes those who desire to know more about the application of science and technology to meet society's food needs and those involved in public education and outreach. It is IFT's hope that the reader will gain a better understanding of the goals or purposes for various applications of science and technology in the food system, and an appreciation for the complexity of the modern food supply. Abstract: This Institute of Food Technologists scientific review describes the scientific and technological achievements that made possible the modern production-to-consumption food system capable of feeding nearly 7 billion people, and it also discusses the promising potential of ongoing technological advancements to enhance the food supply even further and to increase the health and wellness of the growing global population. This review begins with a historical perspective that summarizes the parallel developments of agriculture and food technology, from the beginnings of modern society to the present. A section on food manufacturing explains why food is processed and details various food processing methods that ensure food safety and preserve the quality of products. A section about potential solutions to future challenges briefly discusses ways in which scientists, the food industry, and policy makers are striving to improve the food supply for a healthier population and feed the future. Applications of science and technology within the food system have allowed production of foods in adequate quantities to meet the needs of society, as it has evolved. Today, our production-to-consumption food system is complex, and our food is largely safe, tasty, nutritious, abundant, diverse, convenient, and less costly and more readily accessible than ever before. Scientific and technological advancements must be accelerated and applied in developed and developing nations alike, if we are to feed a growing world population.

Growth of Thermoresistant Streptococci and Deposition of Milk Constituents on Plates of Heat Exchangers During Long Operating Times.

Adhesion of the thermoresistant bacterium Streptococcus thermophilus to the surface of a heat exchanger and deposition of milk constituents during long operating times were investigated. Experiments were carried out on a pilot plant pasteurizer with raw whole and preheated skim milk. Adsorption of calcium, phosphorus and proteins was studied using chemical analysis, scanning electron microscopy and X-ray microanalysis. With increasing operating times the amount of deposits increased gradually on the raw milk side of the regenerative section and in the heating section, whereas on the pasteurized side of the regenerative section no detectable deposits were formed. The bacteria adhering to the plates of the heat exchanger were sampled with a swab technique. The bacteria adhered mainly to the plates in the pasteurized section. Electron micrographs of sample plates showed that the bacteria seemed to adhere directly to the metal surface, without calcium phosphate acting as an intermediary.

Influence of Processing on Nutrients in Foods 1.

Considerable research effort has been devoted to the effect of processing on nutrients in foods. Yet only recently has a systematic approach been used to identify changes in processes which result in improved nutritional content of the product. The catalyst for this systematic approach has been the generation of kinetic data on the influence of environmental factors on the stability of nutrients which can then be used in process models. The effort to quantify reactions important in foods must continue for both nutrients and toxic constituents, but because of limited resources, we should conscientiously choose which environmental factors and which nutrients or toxic substances will be studied. The example of improving nutrient retention in canned foods by choice of time/temperature treatment and by changing geometry is used to illustrate the application of modeling. Additional research effort is warranted on the effect of water activity on nutrient stability, the generation of toxic substances during processing and the bioavailability of nutrients as influenced by processing.

Microflora and Flavor of Wild Rice Fermented Under Different Conditions.

Changes in number and types of microorganisms in fermenting wild rice were studied. The effect of various microorganisms on keeping quality of wild rice during fermentation and on flavor of wild rice was also determined. Addition of microbial cultures and/or nutrient solutions did not increase the storage life of fermenting wild rice held at 21 or 5°C. Refrigeration of rice greatly increased the effective keeping time of the unprocessed grain. Periodic addition of a 0.1% (w/v) (NH4)2SO4 solution apparently decreased the acceptable storage life of refrigerated (5°C) rice. Although unprocessed rice could not be kept beyond 10-14 d at 21 °C without obvious changes in organoleptic quality, rice stored at 5°C remained acceptable for 7 weeks. Steaming wild rice for 15 min before fermentation generally caused a marked reduction in microbial load during the first few days of storage. Rice inoculated with Streptomyces sp. in a circulating nutrient medium to produce an "earthy" flavor was rapidly spoiled by microorganisms indigenous to rice. Cultures of Pseudomonas perolens and Pseudomonas taetrolens inoculated into rice stored at 5°C gave only mild methoxylated-pyrazine (green-earthy) flavors to resulting processed rice. In most treatments, bacteria and molds generally increased during the first week of fermentation, maintained a rather constant number for most of the remainder of the fermentation, and often decreased near the end of storage. Gram-negative, rod-shaped bacteria were the microorganisms most commonly isolated from fermenting wild rice. Many psychrotrophic bacteria were isolated from refrigerated (5°C) rice. Low-temperature storage greatly increased the keeping quality of rice, but unacceptable organoleptic changes eventually occurred at this temperature. Many bacteria isolated from wild rice were facultatively anaerobic Enterobacteriaceae . Although rice contained large populations of various types of microorganisms, the potentially hazardous Bacillus cereus and Pseudomonas aeruginosa were not found.