INTERSTATE SHIPMENT AND STORAGE OF FRESH MUSCADINE GRAPES

Muscadine grapes (Vitis rotundifolia michx.) are highly perishable, with a short harvest season. The objective of this study was to enhance the commercial viability of muscadine grapes by developing harvesting and handling systems through interstate shipment studies, using sulfur dioxide and/or polyethylene overwrap treatments. Cultivars Fry, Summit and Granny Val from Florida, Arkansas and Mississippi, respectively, were shipped from each region to the other in refrigerated trucks for subsequent storage at OC and evaluation at 0, 2, 4 and 6 weeks. Biochemical properties: pH, titratable acidity and degrees Brix, remained fairly constant with time for all cultivars, under all treatments. The cultivar, Granny Val, which was shipped, wrinkled after 2 weeks' storage, but maintained 6 weeks' shelf-life in the in-house study. ‘Summit’ shelf-life was increased to 4 weeks with SO₂ treatment at all test sites while ‘Fry’ became bleached by SO₂. The shelf-life of ‘Fry’ was 6 weeks in the in-house study using     

Fuzzy Clustering in Software Reusability

This paper is concerned with the organization and retrieval of reusable software components with the aid of unsupervised learning. The methods considered of unsupervised learning include FUZZY ISODATA and Kohonen self-organizing maps. The key issues addressed in the study include information retrieval in the presence of incomplete information, and domain specific enhancements of unsupervised learning, including those of partial supervision. The primary intention is to reveal how the learning mechanism can accommodate individual preferences (profile) of the users viewed as a significant component of organization and retrieval algorithms. Numerical examples use a set of MS-DOS system commands and a collection of reusable C++ classes. © 1997 by John Wiley & Sons, Ltd.     

Effect of high intensity pulsed electric fields on enzymes and vitamins in bovine raw milk

Pulsed electric fields (PEF) were applied to fresh bovine raw milk using a laboratory-scale continuous PEF system to study the impact on selected native enzyme activities and on vitamin degradation. The activities of protease, lipase, alkaline phosphatase and lactoperoxidase following PEF treatment at electric field strengths ranging from 15 to 35 kV/cm for treatment times of 12.5 µs to 75 µs were examined. Reductions in enzyme activity, even under the most severe conditions employed, were quite modest, amounting to 14%, 37% and 29% for lipase, protease and alkaline phosphatase, respectively, while the activity of lactoperoxidase remained unchanged. The PEF treatment had no effect on the levels of thiamin, riboflavin, retinol and α-tocopherol in the milk .     

Applications of fractography for aircraft defect causal analysis

Aircraft maintainers and accident investigators routinely seek advice from materials scientists and engineers about the cause of cracks and fractures in air vehicle components. Experience has shown that further failures are more likely to be avoided if the fractographic assessment is carried out in lockstep with the wider evaluation of relevant engineering and operational factors. If possible the fractographer should be in a position to understand the function of the defective component and should be able to assess how this might be affected by the operation of the aircraft system as a whole, and how failure of the component might affect operation of the aircraft. This paper provides evidence from a set of investigations that support the need for a systems approach to failure analysis of aircraft structure and propulsion component defects when causal factors are complex. Effective failure avoidance can be achieved in this way.     

Aggregate production planning using chance-constrained goal programming

Multiple objective models have frequently been proposed to assist in solving aggregate production planning problems. Although such models are an improvement over those with single objectives, demand is usually considered deterministic. For this reason, previous attempts at solving production problems have often lacked realism and could not be successfully applied in many real decision environments. This paper suggests a chance-constrained goal programming (CCGP) approach to production planning which allows the decision maker to specify both probabilistic product demands and production line operating characteristics more in keeping with actual situations. The CCGP approach is based on the sequential solution of a linear programming formulation, allowing efficient solution of large-scale real-world problems using commercially available LP codes. The procedure is demonstrated with a hypothetical example, and proper interpretation of goal achievement is discussed. The findings in the paper are applicable whether preemptive goal programming or a weighted objective function approach is used.     

LUBRICITY INDEX OF MAYONNAISE

The Lubricity Index (LI) is defined as a new parameter to quantitatively evaluate mouthfeel. Rheological data were collected using a helical ribbon mixer viscometer with commercial mayonnaise products. The LI is calculated from changes in apparent viscosity due to temperature and moisture variations that mirror those found in the mouth during mastication. The rate of change in apparent viscosity with moisture and temperature was much lower with a fat free product than regular products resulting in a low LI value. The LI provides a basis for future efforts to understand, and mathematically model, the complicated process of fluid food mastication.     

EFFECTS OF DARK STORAGE TIME AND UV-FILTERED FLUORESCENT LIGHTING DURING DISPLAY ON COLOR STABILITY OF HIGH-OXYGEN MODIFIED ATMOSPHERE PACKAGED GROUND BEEF

Effects of temperature (OC and 4.4C) during dark storage (days 2-9) and display in non-UVand UV-filtered fluorescent lighting on color stability of high-O₂ modified atmosphere packaged "case ready" ground beef was evaluated. Minimal shift in headspace O₂ and CO₂ concentrations occurred during 9 days of storage and display. By day 3, product stored at 4.4C lost redness (Hunter +a) faster than that held at OC. Visual panel ratings for lean color decreased (P > 0.05) after 7 days but were not affected by storage temperature. When packages stored 2, 4, or 6 days at OC were displayed in light, Hunter +a values did not decline (P <0.05) for the first day and in several instances were maintained for 2 days. Panel evaluations of displayed product substantiated high maintenance of redness of lean color. UV-filtering of fluorescent lighting was not necessary for color stability of ground beef during display.     

Postmortem Loss of Carnitine from Skeletal Muscle of Pork and Beef

The carnitine content of beef muscle postmortem was more than twofold higher than the content of pork muscle. For both pork and beef, carnitine was distributed among the fractions, free carnitine ? short-chain acylcarnitine > long-chain acylcarnitine concentration. Based on total carnitine content, the only loss of carnitine from pork muscle occurred as a result of cooking. Cooking also reduced total carnitine content of beef muscle. In addition, total carnitine content of the beef steaks was lower after thawing. Time in the retail case did not influence carnitine content.     

PROTEOLYTIC ACTIVITY OF BACTERIAL STARTER CULTURES FOR MEAT FERMENTATION

Proteolytic activity of fermented meat starter cultures Pediococcus acidiliactic, Lactobacillus sake, Lactobacillus curvatus, Streptomyces griseus, Staphylococcus xylosus and Staphylococcus carnosus was examined after inoculation of sterile beef protein extracts containing 1% dextrose. Analysis for primary amines in extracts generated during fermentation of glucose showed that L. sake had the highest (P<0.05) proteolytic activity. The other cultures ranked from highest to lowest activity as follows : L. curvatus < S. carnosus < S. griseus < P. acidilactici < S. xylosus. All inoculated extracts showed a pH decline by 96 h to pH 3.76-4.31 whereas the control extract remained at 6.0-5.95. All cultures except S. xylosus had CFU increases within 24 h of inoculation. Only L. sake and S. xylosus had counts less than their initial level after 96 h. The results provide evidence that these commercially available starters for meat fermentation do possess significant proteolytic activity when tested using beef protein extracts.     

Reduction of Bitterness and Tartness in Grapefruit Juice with Florisil

Treatment of commercial grapefruit juice with Florisil (activated magnesium silicate) simultaneously reduced the content of citric acid and the bitter compounds limonin and naringin. Ascorbic acid concentration and °Brix (total soluble solids) were not altered by the Florisil treatment. Experienced taste panelists were able to differentiate between the nontreated and Florisil-treated juice on the basis of bitterness and tartness (acidity). The panelists indicated a preference for the Florisil-treated juice.