Nan Unklesbay

Discriminant analysis of vegetable oils by near-infrared reflectance spectroscopy

Discriminant analysis of four vegetable oil types (cotton-seed, peanut, soybean and canola) was performed by near-infrared reflectance spectroscopy. The objective of this study was to provide an alternate method to differentiate vegetable oil types and to classify unknown oil samples. Second derivative spectra of the vegetable oils were subjected to discriminate analysis with Mahalanobis distances principles. A four-wavelength (1704, 1802, 1816 and 2110 nm) equation was derived, which produced a sum of inverse squared distance of 0.0548. Although all four groups were successfully separated with a chi square of 18.9, the soybean oil group is more dispersed in space than the other three groups. Iodine values of the soybean oil samples suggest that this group may have a wide range of hydrogenation states. Discriminant analysis can be successfully used to differentiate vegetable oil types and possibly could also be used to differentiate degree of hydrogenation and oxidative states of oils.

AN APPROXIMATE REASONING TECHNIQUE FOR RECOGNITION IN COLOR IMAGES OF BEEF STEAKS

Visual information plays in important role in food science research and applications. Color and color distribution act as cues in many such discrimination problems. In the determination of degree of doneness in beef steaks, for example, it is the distribution of red and brown which serve as visual indicators. In previous work, we developed capabilities to perform the basic color processing of food images. In this paper we present a methodology, based on approximate reasoning, for automatically determining the degree of doneness from the color images. We define a meaning vector of fuzzy sets for the fuzzy variables representing doneness classes from several of the color histograms of the steak images. We then construct a decision function which produces a fuzzy degree of agreement between the meaning of vector of an unknown sample and the prototypical vector corresponding to each class This approach produces good classification results when the final class memberships are converted to a crisp partition. Ho...

Clinical Nutrition and Foodservice Personnel in Teaching Hospitals have Different Perceptions of Total Quality Management Performance

OBJECTIVE To investigate the perceived total quality management (TQM) performance of their department by clinical nutrition managers and dietitians, and foodservice managers and supervisors, in hospital food and nutrition service departments. DESIGN Using a 2-part questionnaire containing items about 3 constructs of TQM performance and demographic characteristics, participants rated their perceptions of TQM performance. SUBJECTS Employees in 7 Council of Teaching Hospitals. Of the 128 possible respondents, 73 (57%) completed the study. STATISTICAL ANALYSES PERFORMED Correlation analysis to identify relationships between demographic characteristics and TQM performance. Analysis of variance to investigate statistical differences among hospitals and between subject groups and types of employment positions. RESULTS Three TQM constructs--organization, information, and quality management--were evaluated. The clinical nutrition manager and dietitian group had mean ratings between 3.1 and 4.7 (5-point Likert scale); the foodservice manager and supervisor group had mean ratings from 2.7 to 4.0. Education level was significantly correlated (r = 0.44) to performance of employee training in the clinical nutrition group. The number of employees directly supervised was negatively correlated (r = -0.21) to the performance of employee training in the foodservice group. APPLICATIONS As the dynamic roles of dietitians change, many dietitians will occupy management positions in organizations such as restaurants, health food stores, food processing/distribution companies, and schools. This study demonstrates how a TQM survey instrument could be applied to clinical nutrition and foodservice settings. Dietitians will need to assess TQM in their workplace facilities, especially because of the direct links of TQM to productivity and client satisfaction.

Air temperature transfer function of a convection oven

Abstract The effect on air temperature of variations in heater power for a forced convection oven were modelled. The transfer functions for five operating ranges, from 140 °C to 236 °C, were determined experimentally. The oven power control was excited using a pseudo-random binary signal and the resulting effect on the air temperature was measured. From this information, transfer functions in the ARMAX form were determined. It was found that while the denominator coefficients of the system do not vary for different ranges of air temperature, the numerator coefficients of the system do vary significantly.

Determination of doneness of beef steaks using fuzzy pattern recognition

Abstract The c -means and k -nearest neighbor algorithms of pattern recognition were used as methods of determining the degree of doneness of beef ribeye steaks. For each method, an approach employing the theory of fuzzy sets was used in addition to the traditional crisp approach. Steaks were heat processed to various degrees of doneness. The red, green and blue components of the steak images were acquired using a digital image processing system. Values were then converted to the hue, intensity and saturation. The use of the mean and standard deviation of these six values as features was investigated. The means of the red, intensity and saturation and the standard deviation of the red were found to be of most value as features for the classification techniques investigated.

Heat processing menu items with rotating hot air versus deep fat frying

Abstract Two heat processing methods, rotating hot air and deep fat frying, were compared for energy consumption and their effect on quality of four menu items. The rotating hot air system simulated the frying process. The menu items were steak fries, veal patties, chicken strips and cod fillets. Quality attributes measured included product yields, moisture, crude fat, food energy, and shear force. For the small batch sizes studied, the hot air system consumed less energy than the fryer. The moisture content was always less in the fryer; the fat content and food energy levels were always greater. Reasons for these trends were discussed.

A comparison of the destruction of E. Coli O157:H7 in ground beef using pulsed X-rays and gamma rays

In December 1997, the US Food and Drug Administration approved the irradiation of red meat. Depending on the dose applied, exposure of food to ionizing radiation has been found to be effective in destroying pathogenic bacteria, parasites, and some viruses. This paper discusses experiments conducted at the University of Missouri-Columbia, which compare the effectiveness of pulsed X-rays for destruction of E. Coli O157:H7 in frozen ground beef, and the use of gamma rays from a Cobalt-60 radioisotope. Two different sources were used to irradiate the cultures. The source of X-rays, was a novel, compact, desk top, 220 keV, accelerator provided by the Russian Academy of Sciences. A Cobalt-60 source was made available by the University of Missouris Nuclear Research Reactor Facilities. The results of the tests indicate that pulsed X-ray sources have the same effect on E. coli O157:H7 as Cobalt-60 in frozen ground beef. The results of the experiment and the dose required for elimination of E. Coli O157:H7 in frozen ground beef are reported.

Students Study Energy Usage for . Heat Processing Pizzas

Undergraduate students in Food Service and Lodging Management participated in a foodservice energy research project during one semester. They determined the effect of oven paranteters upon energy consuniption during infrared and convective heating of siiyiulated pizzas. Three different oven temperatures and times were studied for infrared and convection ovens. Because of different process materials used, energy comparisons were made within each oven type, rather than between infrared and convective heating. This paper includes guidelines for the organization of suclr a project. The need for the recommended laboratory controls is illustrated by providing their research findings. To illustrate the practical application of the research findings, two scenarios are given, one for a pizza establishnrent, and one for a school foodservice operation.

Modifying Recipes To Promote Energy Efficiency: an Undergraduate Laboratory Project by

In 1977, the Energy Research and Development Administration identified research, education, and training as broadly based support programs and activities vital to the national energy conservation effort.1 In each occupation, ERDA and subsequent observers have noted, the appropriate energy knowledge and skills must be identified so that educators can fill the curricular gaps and students can become effective managers of energy.2,3,4 But too few articles discuss energy education in the food service industry and, until recently, educators saw little need to include energy management concepts in food service curricula. With rising costs and limited supplies of resources, however, food service educators must suddenly disseminate food service energy research findings and methods effectively. Accordingly, this article describes a food service laboratory class project designed to help undergraduate students master some basic energy concepts during food preparation.

Preparing Undergraduate Students To Manage Foodservice Energy

Can an intensive energy study provide undergraduate foodservice management students with sufficient information and experience to affect their future role as managers of foodservice facilities? Early in 1980, the faculty in the Department of Dietetics, Restaurant and Institutional Management at Kansas State University (KSU) posed this crucial question as part of its effort to provide the information and training students need to work effectively