Life Sciences Commons^™

The Effects Of Gamma Irradiation And Calcium Treatment On The Ultrastructure Of Apples And Pears, E. Kovacs, A. Keresztes, J. Kovacs

Food Structure

The post-storage quality of fruits depends on the ultrastructure of the outer tissues and on the fruit mineral composition (mostly on calcium). Pectins and their bonds with calcium play a central role in the tissues during ripening.

During senescence the middle lamella disappears from the cell walls, the fruits become soft and cell wall reticulation can be seen. There are changes within the cells too; plasmalemma separates from the wall, tonoplast from the cytoplasm, and plastids, mitochondria and nuclei are disorganized.

The ultrastructure of the skin and flesh of apples and pears were studied as a function of treatments (calcium, …

Lactose Crystallization In Commercial Whey Powders And In Spray-Dried Lactose, Zenichi Saito

Food Structure

Two kinds of whey powder, one containing only amorphous lactose, and the other containing precrystallized lactose, and spray-dried amorphous lactose were examined for particle structure by scanning electron microscopy. Lactose crystallization under 75th relative humidity was studied by X-ray diffraction analysis. Scanning electron microscopy appeared to detect changes due to lactose crystallization on the smooth surface of the particles examined. Lactose crystallization s tarted within 30 minutes after exposure to the humid atmosphere. Both a-lactose hydrate and B-lactose crystals were detected in the s pray- dried amorphous lactose by X -ray diffraction within 40 minutes under the humid conditions. Only …

Application Of Scanning Electron Microscopy And X-Ray Microanalysis To Investigate Corrosion Problems In Plain Tinplate Food Cans And Examine Glass And Glass-Like Particles Found In Canned Food, James E. Charbonneau

Food Structure

Scanning Electron Microscopy (SEM) and X-ray Microanalysis (EDS) have been used to investigate product container interaction problems in plain tinplate metal food containers and to examine glass and glass-like particles that were found in canned food.

Through the use of SEM-EDS, it was determined that: sulfate containing particles from the cannery cooling water reacted with exposed iron or tin-iron alloy on the tinplate surface causing an external rusting problem; sulfur dioxide was responsible for a container discoloration and a pitting corrosion problem in canned fruit nectar; hydrogen sulfide produced from the SO2-tinplate reaction was the cause of an associated off-odor …

The Use Of Transmission Electron Microscopy To Study The Composition Of Pseudomonas Fragi Attachment Material, Paula J. Herald, Edmund A. Zottola

Food Structure

Electron microscopy techniques were used to study the attachment matrix of Pseudomonas fragi used to demonstrate the presence of attachment fibrils of P. fragi adhered to stainless steel. Transmission electron microscopy (TEM) was used to examine thin sectioned cells strained with ruthenium red or alcian blue. Extracellular substances surrounding cells stained with ruthenium red or alcian blue had a mat- or spike-like morphology. This indicated that these substances were acidic mucopolysaccharides that may be involved in the attachment of P. fragi to food contact surfaces.

Scanning Electron Microscopy Of Cellular Structure Of Granny Smith And Red Delicious Apples, Gassinee Trakoontivakorn, Max E. Patterson, Barry G. Swanson

Food Structure

Immature and mature Granny Smith and Red Delicious apples (Malus domestica Borkh . ) were studied with scanning electron microscopy (SEM). Parenchyma cells were observed to form a net-like pattern in sections transverse to the stem-calyx of the apple. Bundles of about six intact cells were connected, creating large intercellular spaces. The intercellular spaces were different in shape from different perspectives to the cut surfaces ; round in stem-calyx transverse sections and elliptical in stem-calyx cross sections. Cell areas, cell lengths and intercellular space areas were determined with image analysis. The patterns of mature apple cell structure of both cultivars …