Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 87-94). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 170-178). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 170-178). Also available on the Internet.

Texture, a critical property of Asian wheat noodles, is normally assessed by sensory evaluation. However, sensory evaluation may be impractical for wheat breeders and noodle researchers who need to evaluate a large number of samples and have limited sample. Instrumental Texture Profile Analysis (TPA) has been widely employed to evaluate Asian wheat noodle texture. Nevertheless, a standardized method for performing TPA on these products has not been established. A series of studies were conducted to develop a testing method to best relate TPA results to sensory texture characteristics of Asian wheat noodles. First, the optimum TPA testing conditions (crosshead speed and degree of deformation) were determined for each noodle category (alkaline, instant fried, salted flat, and salted round), and were defined as the conditions which best related their results to the sensory data. Partial Least Squares (PLS2) was used to examine relationships between sensory first-chew characteristics (hardness, cohesiveness, springiness, denseness, starch between teeth, and toothpull) and TPA output (peak areas and heights). Response Surface Methodology determined the optimum TPA conditions (crosshead speed and % deformation) as follow: 1 mm/s and 85 % for alkaline, 1 mm/s and 70% for instant fried and salted round, and 5 mm/s and 65 % for salted flat noodles. Second, the effects of two sample cooking factors: noodle weights (20, 50, 100 g) and noodle to water ratios (1:10, 1:20) and three holding factors: media (with, without water), temperatures (25, 55 °C), and times (2, 15, 30 min), on the TPA results were investigated. Cooking factors did not significantly affect the TPA results but higher holding temperatures, the use of water as a holding media, and longer holding time significantly decreased most TPA parameters' values. Third, relationships between TPA and sensory first-chew parameters were examined for each noodle category. Predictive models of each sensory first-chew attribute were developed using linear and nonlinear (Fechner and Stevens) models, with single and multiple parameters. Hardness could be satisfactorily predicted by a single TPA parameter (area 1 or area 2), but other attributes required multiple parameters in the models to be satisfactorily predicted. Different model types were selected for each sensory attribute and noodle category. TPA peak area 1 and 2 were the best predictors for first-chew characteristics of cooked Asian wheat noodles. / Graduation date: 1998

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Anticipatory satiety is the ability to reduce meal size when the diet at that meal is consistently followed by a short time interval to the next access to food. This prediction of intake is learnt, i.e. based on the association of a food's sensory characteristics with some consequence(s) of ingesting it. / Two pilot studies were conducted using male Sprague-Dawley rats in which (1) the ability of food texture to cue fasting duration was indicated by evidence of anticipatory satiety in the low-fat powder-long/paste-short group and in the high-fat paste-long/powder-short group and (2) the pattern of anticipatory satiety was seen only in the low-fat granules-long/powder-short group. / In the main experiment (n = 9), anticipatory satiety was reached twice in the highfat powder-long/pellet-short group on days 16--23 (p ≤ 0.1) and once in the low-fat pellet-long group/powder-short on days 20--23 (p ≤ 0.1). The acquisition of texture-cued fasting-anticipatory satiety seems to depend upon high-energy density of the diet and the utilisation of textures which make it easier for the rats to eat.

Thesis (doctoral)--Helsinki University of Technology, 2008. / Includes bibliographical references. Also available on the World Wide Web.

Irradiation sterilization of precooked, hermetically sealed meat provides a shelf-stable, ready-to-eat product that can be stored for long periods of time without refrigeration. The Atomic Energy Corporation of South Africa started to develop precooked, shelf-stable meat products during the late 1970’s, using gamma radiation from a 60Co source at dose levels of at least 45 kGy. A number of meat dishes were successfully developed though problems were experienced with the texture of dry-packed roast beef slices, as these were found to be slightly dry. Polyphosphates can possibly be used to alleviate the textural problems found in precooked irradiation-sterilized meat because polyphosphates are known to increase the water binding properties of meat proteins, resulting in a juicy, tender product. The choice of cattle breed used for the preparation of precooked meat dishes may also affect cooked meat texture, due to genotypic differences in the amount and especially the solubility of collagen. Biceps femoris and semitendinosus muscles obtained from Afrikaner (Bos Indicus), Hereford (Bos Taurus) and Simmental (Bos Taurus) steers were treated with low levels of sodium tripolyphosphate (0.3% and 0.5%) and tetrasodium pyrophosphate (0.22% and 0.36%) in combination with 0.7% salt. The precooked meat was vacuum packed in flexible pouches and irradiated in the frozen state (-40°C) with a 60Co gamma source until a minimum target dose of 45 kGy was reached. Various physico-chemical tests as well as descriptive generic sensory evaluation were performed on the samples to determine the effect of breed, polyphosphate treatment and irradiation on the physico-chemical and sensory properties of irradiated precooked beef. Cattle breed affected the texture of precooked, irradiated, shelf-stable beef, with Afrikaner biceps femoris giving a more tender, juicy product than that of Hereford and Simmental. The low levels of polyphosphates used in combination with salt successfully increased the juiciness and tenderness of precooked, shelf-stable beef. There was little difference in the physico-chemical and sensory results obtained from samples treated with the two different polyphosphates, or the level at which the polyphosphates were administered. Irradiation sterilization of precooked beef resulted in a tender product. Comparison of irradiated and non-irradiated samples revealed that the irradiated samples had longer sarcomere and I-band lengths, and shorter A-band lengths, which explained the increased tenderness in irradiated samples. An increase in both soluble collagen and % collagen solubility after irradiation sterilization further substantiated the tenderness results. Treatment of the biceps femoris with low levels of sodium tripolyphosphate or tetrasodium pyrophosphate in combination with salt, prior to cooking and irradiation, resulted in a juicy, shelf-stable product. Irradiation sterilization did, however, produce a detectable wet dog flavour and aroma, and more research is required into improving the flavour and aroma of irradiation sterilized beef. Although this research indicated that irradiation of cooked, polyphosphate treated Afrikaner meat resulted in the most tender and juicy end-products, it is recommended that sensory evaluation using a consumer panel also be conducted, in order to determine if this level of tenderness is acceptable, or if it is over tender due to excessive degradation of the connective tissue. / Dissertation (MSc)--University of Pretoria, 2005. / Food Science / unrestricted

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published_or_final_version / Zoology / Doctoral / Doctor of Philosophy