Malcolm C. Bourne

Bio: Malcolm C. Bourne is an academic researcher from Cornell University. The author has contributed to research in topics: Viscosity & Blanching. The author has an hindex of 35, co-authored 106 publications receiving 5084 citations.

Food Texture and Viscosity: Concept and Measurement

Abstract: Preface 1. Texture, Viscosity and Food 2. Texture-Body Interactions 3. Physics and Texture 4. Principles of Objective Texture Measurement 5. Practise of Objective Texture Measurement 6. Viscosity Measurement 7. Sensory Methods of Texture and Viscosity Measurement 8. Correlation Between Physical Measurements and Sensory Assessments of Texture and Viscosity 9. Selection of a Suitable Test Procedure i. Appendix I - Suppliers of Texture and Viscosity Measuring Instruments Appendix II - Effect of Temperature on Texture Measurements Appendix III - Conditions of Testing Foods using the TA.XT2 Texture Analyser References Index

Chapter 1 – Texture, Viscosity, and Food

Abstract: Publisher Summary The four principal quality factors in food include its appearance, flavor, texture, and nutrition. Appearance, flavor, and texture are the “sensory acceptability factors” because they are perceived by the senses directly. Nutrition is a quality factor that is not perceived by the senses. The sensory acceptability factors of foods are extremely important because people obtain great enjoyment from eating their food. The importance of texture in the overall acceptability of foods varies widely, depending upon the type of food. Achieving the desired textural quality of food has important economic considerations. The importance of texture, relative to other quality factors of foods, may be affected by culture. The chapter describes the vocabulary of texture of food, as it is very important, especially in sensory testing and consumer verbalizations of quality. It is also reported that time of day exerted a strong influence on textural awareness and flavor. The chapter also presents the difference between texture and viscosity.

A psychoacoustical theory of crispness

Abstract: The theory is proposed that crispness is primarily an acoustical sensation. The frequency spectra and the amplitude-time characteristics of sounds produced by biting crisp foods were studied. The frequencies present in crisp sounds cover a broad range. Amplitude-time plots show irregular variations in loudness with time. A model system involving a generalized cellular structure is proposed to explain the generation of a crisp sound. As a crisp cellular material is crushed, a series of sounds is produced. Each sound is the result of the rupture of a single cell or cell wall.

Principles of Objective Texture Measurement

Abstract: This chapter discusses the principles of objective texture measurement. There is such a wide range in types of foods and the types of textural and rheological properties that they exhibit, and such a wide variety of methods used to measure these properties, that it becomes necessary to attempt to classify them into groups to understand the system. It is possible to classify texture measurements according to the commodity that is being tested, for example, tests that are used for cereals, meat, fish, poultry, vegetables, fruit, dairy products, fats, confectionery, beverages, legumes and oilseeds, and miscellaneous foods. The classification of texture measurements on the basis of commodity or the type of textural properties is useful but what is probably a better type of classification is based on the type of test that is used, because many tests are applicable to more than one type of food. When food is placed in the mouth, the structure is destroyed by the act of mastication until it is ready to be swallowed. The basic process of mastication occurs regardless of what kind of food is in the mouth. Therefore, it seems logical to concentrate on the type of test rather than the nature of the food. The chapter discusses the types of tests for measuring food texture.

Effect of blanching treatments on the firmness of carrots

Abstract: Carrots (26 varieties) were subjected to two blanching-in-water treatments prior to being canned in the conventional manner. (1) 4-5 min blanch at 212°F, (2) 20–30 min blanch at 165°F. All of the low temperature blanch carrots were firmer than the corresponding high temperature treatment. Blanching was carried out at 130°, 150°, 170°, 190°, 212° F. The firmness, free methanol and pH of these treatments all showed the same trend, increasing as blanch temperature was raised from 130® to 170®F and decreasing as blanch temperature was raised from 170® to 212®F. This evidence supports the conclusion that the increase in firmness is caused by the effects of pectin methyl esterase PME) which is activated by the low temperature blanch and inactivated by the high temperature blanch.

Qualitative Quality: Eight “Big-Tent” Criteria for Excellent Qualitative Research

Abstract: This article presents a model for quality in qualitative research that is uniquely expansive, yet flexible, in that it makes distinc- tions among qualitative research's means (methods and practices) and its ends. The article first provides a contextualization and rationale for the conceptualization. Then the author presents and explores eight key markers of quality in qualitative research including (a) worthy topic, (b) rich rigor, (c) sincerity, (d) credibility, (e) resonance, (f) significant contribution, (g) ethics, and (h) meaningful coherence. This eight-point conceptualization offers a useful pedagogical model and provides a common language of qualitative best practices that can be recognized as integral by a variety of audiences. While making a case for these markers of quality, the article leaves space for dialogue, imagination, growth, and improvisation.

Extending and Measuring the Quality of Fresh-cut Fruit and Vegetables: a Review

Abstract: The market sales of ready-to-use fresh vegetables have grown rapidly in recent decades as a result of changes in consumer attitudes, especially consumption of fresh-cut lettuce and carrot due to their use in prepared salads. Chlorine solutions have been widely used to sanitise fruit and vegetables in the fresh-cut industry. However, the association of chlorine with the possible formation of carcinogenic chlorinated compounds in water has called into question the use of chlorine in food processing. There is a real need to find alternatives for preservation of fresh-cut fruit and vegetables in order to improve the efficacy of washing treatments. Alternatives or modified methods have been proposed, as antioxidants, irradiation, ozone, organics acids, modified atmosphere packaging, whey permeate, etc.; however, none have yet gained widespread acceptance by the industry. For this reason the development of alternatives and markers in order to measure the efficacy of these alternatives are needed.

Critical Review of Techniques and Methodologies for Characterization of Emulsion Stability

Abstract: The efficient development and production of high quality emulsion-based products depends on knowledge of their physicochemical properties and stability. A wide variety of different analytical techniques and methodologies have been developed to characterize the properties of food emulsions. The purpose of this review article is to provide a critical overview of the most important properties of emulsions that are of interest to the food industry, the type of analytical techniques that are available to measure these properties, and the experimental protocols that have been developed to characterize the stability of food emulsions. Recommendations are made about the most suitable analytical techniques and experimental protocols needed to characterize the stability and properties of food emulsions.