Food Science Commons^™

Microstructure Of Set-Style Yoghurt Manufactured From Cow's Milk Fortified By Various Methods, A. Y. Tamime, M. Kalab, G. Davies

Food Structure

Five different batches of skim milk were prepared and fortified by the addition of skim milk powder (SMP) or sodium caseinate (Na-cn) or by concentration using a vacuum evaporator (EV), ultrafiltration (UF), or reverse osmosis (RO) to contain similar levels of protein (5.0-5.5%). Yoghurts were made by inoculating the milks with one of 3 commercial yoghurt starter cultures and by incubating the mixes at 42°C for 2.5 h. The following factors were found in this study to affect firmness of the yoghurts: (a) Lactic acid production (acidity) - Yoghurts containing 1.02% of lactic acid or more (pH 4.54 or less) …

A Simple Procedure For The Preparation Of Stirred Yoghurt For Scanning Electron Microscopy, Paula Allan-Wojtas, Miloslav Kalab

Food Structure

Stirred yoghurt is aspirated into agar gel tubes having 1.2 mm interior diameter, fixed in glutaraldehyde , dehydrated in ethanol freeze - fractured under liquid nitrogen and critical-point dried. Agar gel encapsulation protects the sample and prevents it from disintegration during the preparative steps. Scanning electron microscopy of the mounted fragments reveals the corpuscular microstructure of this type of yoghurt which develops due to stirring and pumping of the product during manufacture.

Ultrastructural Aspects Of Spun Pea And Fababean Proteins, D. J. Gallant, B. Bouchet, J. Culioli

Food Structure

The ultrastructure of pea and fababean spun proteins has been studied by SEM and TEM as a function of dope pH and washing bath salt concentrations. The textural properties {mechanical resistance, moisture content) and diameter of the fibres have been determined.

Spinning was only possible when dope pH was higher than 11. An increase in dope pH from 11.5 to 13 induced a shear strength increase whereas the moisture content and the diameter of the fibres decreased . The structure of the fibres became more compact and changed from an aggregate of spherical particles to a tridimensional network. When dope …

Ultrastructural Studies Of Raw And Processed Tissue Of The Major Cultivated Mushroom, Agaricus Bisporus, E. M. Jasinki, B. Stemberger, R. Walsh, A. Kilara

Food Structure

Commercial mushroom processors currently lose approximately 30 percent of the mushroom weight due to shrinkage during processing (blanching and canning) , resulting in substantial economic losses . Microscopy was used to assess the extent and type of chemical and structural changes induced by processing mushrooms and causing shrinkage. Scanning electron microscopy revealed that the processing operations including vacuum hydration , blanching , and thermal treatment do not damage the integrity of the tissue. Light microscopy revealed that the morphology of the tissue, shape and spacing of cells, appear similar for raw and processed mushroom tissue . However, the intra ce …