TOMATO PERICARP TISSUE RESONANCE AND ITS USE IN TEXTURE EVALUATION

The use of resonance properties, measured by dynamic oscillation using a constant stress rheometer, as textural parameters for excised pericarp tissue of tomato ( Lycopersicon esculentum Mill cv Trust) fruit during 21 days of ambient temperature ripening was assessed relative to the large-deformation behavior measured by flat-plate compression. The resonance frequency (f_r) of excised tissue discs decreased significantly (P < 0.05) over the first 9–12 days, and then approached a relatively low and constant value with subsequent ripening. A significant (P < 0.05) increase in associated resonance strain amplitude (y_max) became apparent after the first 9–12 days of tomato fruit ripening. Ripening-associated changes in bioyield and failure strengths, toughness, and apparent elastic and failure deformability moduli derived from flat-plate compression tests were similar to those observed for tissue f_r. Results were consistent with a change in the dominant mode of tissue failure from cell relaxation and rupture to debonding after 9–12 days of fruit ripening. A significant (P < 0.05) semilogarithmic relationship was observed between f_r, but not y_max, and compression parameters, allowing for reasonable prediction of large-deformation behavior on the basis of measurement of only f_r. The results demonstrate that resonance frequency may provide a useful parameter in the evaluation of tomato pericarp tissue texture.     

Response surface modelling for cleaning and disinfecting materials used in milking systems with electrolysed oxidizing water

Electrolysed oxidizing (EO) water is produced by passing a DC current through a weak sodium chloride solution, resulting in alkaline and acidic EO water. The goal of this research was to determine whether EO water could be used as an acceptable cleaning and disinfecting agent for materials used in pipeline milking systems. Small pieces of materials commonly used in milking systems were soiled using raw milk inoculated with a cocktail of four bacterial cultures similar to those commonly found in raw milk, and then cleaned by soaking in alkaline EO water followed by soaking in acidic EO water at various treatment times and temperatures. Effective treatment time and temperature combinations were determined by response surface design for a temperature range of 25–60°C and a time range of 5–20 min. Treated materials were evaluated by aerobic plate counts and ATP bioluminescence to assess the disinfecting and cleaning effectiveness of EO water. Most of the treatments at 60°C and several treatments at lower temperatures successfully removed all detectable bacteria and ATP. Overall, the results of this study indicated that EO water has the potential to be used as a cleaning and disinfecting agent for materials used in milking systems.     

Flavor Evaluations of Florida Frozen Concentrated Orange Juice Blended from Concentrates Produced with Varying Extraction Yields

Flavor evaluations are presented for two samples of frozen concentrated orange juice (FCOJ). Each sample of 42°Brix commercial type FCOJ was prepared by blending concentrates of juices of four cultivars (27% Hamlin, 20% Pineapple, 50% Valencia and 3% Murcott). One sample was made only with concentrates from low yield juices of each cultivar and the other sample was made only from concentrates from high yield juices of the four cultivars. Both the samples were rated very good flavor when graded according to USDA standards for grades of FCOJ, but showed lower scores for high yield than for low yield juices. Results of six industry flavor panel evaluations are presented.     

Hydration behaviour of synthetic saponite at variable relative humidity

Hydration behaviour of synthetic saponite was examined by X-ray powder diffraction simulation at various relative humidities (RH). The basal spacing of the Ca-saponite increased stepwise with increase in RH. The (00l) reflections observed reflect single or dual hydration states of smectite. Quasi-rational, intermediate, or asymmetrical reflections were observed for all XRD patterns and reflecting heterogeneity of the samples, especially along the transition between two hydration states.     

SOCIAL INTERACTION IN MIXED‐INCOME DEVELOPMENTS: RELATIONAL EXPECTATIONS AND EMERGING REALITY

ABSTRACT: In many cities, public housing has come to exemplify concentrated urban poverty and the social problems associated with it. One major policy response to addressing these problems is the demolition and redevelopment of public housing complexes as mixed‐income communities. Several theoretical propositions that lie behind this policy are based on assumptions about the ways in which living among higher‐income residents can lead to relationships and interactions that may benefit poor people. Based on in‐depth qualitative research in two mixed‐income developments in Chicago, this paper explores the dynamics of social interaction in an effort to better understand the processes and factors that influence such interaction on the ground, the differential experience of residents from different backgrounds, and the factors that contribute to their decision‐making about and interpretation of social relations with their neighbors. This analysis helps to better interpret the findings of earlier studies and craft more informed expectations about such interactions and their likely effects.     

Fluctuations in light intensity modulate ion fluxes from grape berry mesocarp: direct evidence from microelectrode ion flux estimations

Canopy architecture and light spectral composition have long been considered as important factors determining grape juice acidity and K+concentrations. In this study, we provide direct evidence that fluctuations in intensity of light incident on berry tissue may significantly modulate net ion fluxes from and into the berry mesocarp. The MIFE technique was used to quantify fluxes of K+, H+, and Ca²⁺in Pinot Noir and Emperor grape berries. Transition from dark to light induced complex multiphase kinetics of K+flux resulting in significant shift towards net K+uptake by the peripheral mesocarp tissue. When light intensity was modulated in a square-wave manner with a period of 5 to 15 min (mimicking periodicity of natural variations during a typical autumn day in Hobart), K+flux oscillated with the same frequency and a magnitude of about 100 nmol/m²s. Changes in H+and Ca²⁺fluxes showed high positive (R = 0.8) and negative (R = 0.9) correlation, respectively, with those in K+. To the best of our knowledge, these data from excised fruit provide the first reported evidence that light directly incident on bunches may modulate apoplasmic pH and K+concentration in grape. Possible underlying mechanisms are discussed.     

CYBERNETICS,TELEOLOGY, AND SCIENCE

Cybernetics has evolved far beyond the problems of servomechanics and simple models of purposive behavior into a substantial body of theory with potential for resolving long-standing controversies surrounding the role of teteological concepts and reductionism in scientific explanation. The diverse research contributing to modem cybernetics views natural adaptation, goal-directed behavior, and conscious purpose as varying expressions of circular causal, recursive, and system/environment relationships along a continuum of organized complexity. This mode of analysis suggests that hierarchy in the sciences springs from a hierarchy of causal circuits in the structure of ideological phenomena, for which the dual, part/whole nature at any particular level forces a bifurcation of discourse into distinct “logical types” according to the observer's focus. The cybernetic paradigm may thus provide connecting tissue by which the full spectrum of explanation, from physicochemical to teleological, is joined in a coherent scientific framework constituting “reduction in principle” of living systems, even while truly meaningful translation of one science into another is precluded by the disparate logics of their subject matter.     

PORCINE LONGISSIMUS GLYCOLYTIC POTENTIAL LEVEL EFFECTS ON GROWTH PERFORMANCE, CARCASS, AND MEAT QUALITY CHARACTERISTICS

Animals (n = 72) with longissimus glycolytic potential (GP) values ranging from 113.8 to 301.1 μmol/g of tissue, were classified as having low (n = 24), moderate (n = 24), and high (n = 24) GP levels. Meat quality measurements such as longissimus ultimate pH and subjective color score decreased, while Hunter L* values, percentage drip loss and purge loss increased for animals classified as having either high or moderate GP levels compared to those with low GP values. Animals with higher GP had decreased longissimus protein content and improved taste panel tenderness scores and lower shear force indicating superior eating quality. Increasing aging time from 2 to 21 days decreased shear force and improved taste panel tenderness scores. These data indicate that both glycolytic potential level within the muscle and aging time can have significant effects on pork quality characteristics.