CALIBRATION OF THE PEA TENDEROMETER AND A COMPARISON OF TENDEROMETER READINGS FROM THREE COUNTRIES

The validity of the Texture Test System (TTS) as a reference calibration instrument for the Pea Tenderometers has been evaluated. The factors influencing the results are discussed. A linear correlation between TTS values and tenderometer units has been obtained with a correlation coefficient of at least 0.98. Calibration of the Pea Tenderometers by means of the TTS is now the standard procedure in Sweden. A comparison has been made between Swedish, English and American tenderometer readings. The results show that Swedish and English tenderometer readings are quite similar, whereas the U.S. values differ by up to 9 TU depending on the sample tenderness.     

DATA ADJUSTMENT FOR NON-REACTIVE BATCH OR STEADY-STATE PROCESSES

An analytical method was developed to adjust inconsistent process data by a least-sum-of-squares technique to “best” meet all material balance constraints. One complete data set composed of “M” stream flow rates with “N” components in each stream was used from either batch or steady-state non-reactive processes to define an unconstrained sum-of-squares adjustment function

Derivatives of the unconstrained sum-of-squares adjustment function with respect to each variable were set to zero yielding a set of non-linear algebraic equations. The entire non-linear set was solved by converging on only M— 2 search variables as compared to conventional methods requiring N(M — 1) — 1 search variables.     

LIQUID CIRCULATION PATTERNS AND THEIR EFFECT ON GAS HOLD-UP AND AXIAL MIXING IN BUBBLE COLUMNS

Liquid velocity profiles in a bubble column were measured with the aid of a hot-film anemometer. Two different types of profiles were detected that were characterized by the formation of a boundary layer at the column wall. Under slow flow conditions, the boundary layer is large and controls the liquid velocity profile, but in turbulent flow the boundary layer is very small and has no significant effect on the velocity profile. Microscopic and macroscopic balances were used to predict both the liquid velocity profile and the average liquid velocity.

The effect of the liquid velocity profile and average velocity on axial dispersion and gas-hold-up are analyzed and design procedures are recommended.     

AIDS: The Urban Policymaking Challenge

ABSTRACT: The development and spread of Acquired Immunodeficiency Syndrome (AIDS) in American urban areas is challenging established policy making structures and patterns in a variety of ways. AIDS is forcing urban policymakers to engage in unusual efforts at large and nonincremental change while possessing relatively little understanding of the ultimate nature and course of the disease. A variety of uncertainties exist, involving the future scope and development of AIDS, current and future treatment costs, legal and administrative responsibilities, workplace concerns, education efforts, financing methods, and political effects. As a consequence, those making AIDS policy must rely upon what Jones (1984) terms ambitious decisionmaking styles. Successful control of AIDS will require decentralized policymaking centered on experimental efforts in each urban area confronted with the disease. Given the wide range of uncertainties regarding the nature of AIDS and effective policy measures, it is unlikely that a truly national AIDS policy will be established in the immediate future.     

THE IMPACTS OF PRODUCT ACCEPTABILITY, BRAND VALUE AND PRICE ON RESPONSES OF FOODSERVICE PROFESSIONALS TO BULK TURKEY

The objective of the research is to assess the contribution of product itself, brand image, and stated price, respectively, as determiners of purchase intent for foodservice managers and food brokers. The paper presents two sets of results. The first set shows that on a blind basis products differ moderately in perceived quality, but perceived quality may change with branding. The effect of branding is idiosyncratic, varying by product, usage behavior of the panelist, and panelist's job. The second set of results shows that price is far more important than product quality as a determiner of purchase intent, but the interplay of quality, price and purchase intent varies by the nature of the respondent.     

SURVIVAL OF VIBRIO VULNIFICUS AT REDUCED TEMPERATURES AND ELEVATED NUTRIENT

Studies were conducted on the survival of the human bacterial pathogen, Vibrio vulnificus, in heart infusion broth held at 5, 10 and 15°C. Culturability was monitored by plate counts on heart infusion agar, and viability by examination of electron transport activity. Whereas V. vulnificus demonstrated growth at 15°C, a rapid loss of culturability for cells held at the lower temperatures was observed. At all temperatures, however, a significant portion of the population was found to remain viable over the 28 day study period. The ability of V. vulnificus cells to metabolize exogenously supplied nutrient at reduced temperatures was also examined as an indicator of viability. Cells were able to rapidly take up and respire mixed amino acids at 9 and 13°C, whereas cells incubated at 2°C showed relatively little metabolism of the labeled substrates. Like the growth and viability study, the radiotracer study indicates survival of V. vulnificus at reduced temperatures, although with reduced rates of activity. The possible implications of these findings for the transport and storage of shellfish is discussed.     

Effect of Electrical Charge on Attachment of Salmonella typhimurium to Meat Surfaces

Treating tissue with electrical current was found to affect both the initial attachment and total numbers of attached Salmonella typhimurium to meat tissues. When lean tissue was attached to the positive terminal of the power supply operating at 50 volts/125 mA DC, the total number of attached cells increased. There was no effect when the samples were attached to the negative terminal. There was a significant (P<0.05) effect on the percentage of strongly attached bacteria with an increase in treating time. Electrical current was found to increase the percentage of strongly attached cells immediately after the current was applied.     

USING BROOKFIELD DATA AND THE MITSCHKA METHOD TO EVALUATE POWER LAW FOODS

Mitschka proposed a simple technique to calculate average shear stress and average shear rate from data obtained with Brookfield viscometers. It allows for estimation of the apparent viscosity, the flow behavior index, and the consistency coefficient of power law fluids. This method was evaluated for typical shearthinning foods (banana puree, salad dressing, enchilada sauce, and pancake syrup) and found to have excellent potential for quality control testing in the food industry. Results compared favorably with those obtained with a standard cone and plate viscometer.