عنوان

Influence of three poultry defeathering systems on morphology of turkey skin as related to the adhesion and penetration of Salmonella typhimurium

Number

TLpq303997195

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Influence of three poultry defeathering systems on morphology of turkey skin as related to the adhesion and penetration of Salmonella typhimurium

General Material Designation

[Thesis]

First Statement of Responsibility

J.-W. Kim

Subsequent Statement of Responsibility

S. Doores

Name of Publisher, Distributor, etc.

The Pennsylvania State University

Date of Publication, Distribution, etc.

1992

Specific Material Designation and Extent of Item

149

Dissertation or thesis details and type of degree

Ph.D.

Body granting the degree

The Pennsylvania State University

Text preceding or following the note

1992

Text of Note

The influence of three different poultry defeathering systems (conventional, kosher and steam-spray system) on microtopography of turkey skin and the consequent effect on the attachment and penetration of Salmonella typhimurium were examined. Common flocks of turkeys were processed and breast skins were collected immediately after the defeathering step at each plant. Skin samples were irradiated, inoculated with S. typhimurium and examined with SEM, TEM, light microscopy and microbiological plating techniques. Penetration and distribution of cells within each skin were assessed by cryostat sectioning and fluorescence microscopy. Conventional skin had a comparatively smooth surface and allowed little attachment of cells. A thin layer of epidermis (a portion of stratum germinativum) remained in conventional skin and appeared to prohibit the penetration of cells. Consequently, most of the attached cells resided in the upper 50 mum layer of skin. Its soft fatty surface seemed to contribute to the loose attachment of cells. Kosher skin retained most of the epidermal layers due to cold water processing and appeared to be very rough with its delaminated keratinized epidermis. Few cells were observed on the surface of kosher skin, possibly due to a very hydrophobic surface; however, its high Sm-value reflected the entrapment of cells within a scaly skin structure. Cryostat sectioning showed the penetration of cells even down to the dermal layer (150 mum). Although most of the epidermis was retained in kosher skin, the characteristic long picking line of the kosher system seemed to cause mechanical damage to the skin and allowed deep penetration. Steam-spray skin lost most of the epidermis during processing and exposed highly convoluted dermis as a new surface for bacterial adhesion. The collagenous connective tissue on steam-spray skin appeared to be responsible for three-times higher attachment rate. However, the loss of whole epidermis allowed the deepest and highest penetration of cells among the three types of skin, probably through skin channels opened between collagen fiber bundles. As inoculation time increased, the number of cells attached and formation of attachment fibrils were increased in steam-spray skin. The above results suggested a good correlation between adhesion of S. typhimurium and both skin microtopography and physicochemical properties exerted by exposed skin.

Biological sciences

Food science

Food science

Microbiology

J.-W. Kim

S. Doores

Electronic name

p

[Thesis]

276903

a

Y