STORAGE OF RETORT POUCH BEEFSTEAK AND BEEF STEW PACKED UNDER FOUR HEADSPACE LEVELS

Changes in specific physico-chemical and sensory attributes as well as acceptability of beefsteak and beef stew Meal-Ready-to-Eat (MRE) components packed under different headspace levels (10, 20, 30 and 40 cm³) and stored at selected temperatures of 4, 27 and 38C (40, 80 and 100F) were evaluated over a six month period. No significant changes in microbial counts, pH, residual oxygen, color, hardness and oxidation occurred in retort-packed beefsteak or beef stew. Unlike beefsteak, beef stew received acceptable scores by consumers during all six months of analysis. Consumers' lack of familiarity with beefsteak may have negatively influenced product acceptability. Beefsteak and beef stew acceptability and specific attributes, particularly moistness and firmness, were detrimentally affected by high storage temperatures. Headspace may be increased to 40 cm³ without significant detrimental effects on product quality and acceptability of beefsteak or beef stew.     

Rheological Properties of Solutions and Emulsions Stabilized with Xanthan Gum and Propylene Glycol Alginate

The rheological effects of propylene glycol alginate (PGA) added to solutions and model emulsions containing xanthan gum (XG) were studied using controlled stress rheometry with concentrations appropriate for salad dressings. For samples with XG and XG + PGA blends, solutions and emulsions showed a Newtonian plateau at low shear stresses. The Newtonian plateau of a solution accurately predicted (r²= 1.00) the Newtonian plateau for an emulsion of equivalent gum concentration. Addition of PGA to constant levels of XG showed a more than additive increase in the Newtonian plateau viscosity for solutions and emulsions. For XG aqueous solutions, pseudoplasticity decreased upon addition of PGA. Storage and loss moduli increased with addition of PGA to XG for solutions and emulsions, although G’ for solutions of PGA alone were negligible.     

EXTENDED VALIDATION OF A SIMPLIFIED EXTRACTION AND GRAVIMETRIC DETERMINATION OF TOTAL FAT TO SELECTED FOODS

A simplified method for chloroform/methanol extraction and gravimetric determination of total fat previously published for diet composites was tested on additional foods, including milk, cheese, fried snack foods, nuts/seeds, salad dressings, baked goods, meat, fish/shellfish and fruits/vegetables. Homogenized food composites and certified reference materials (CRMs) were analyzed using the existing method involving, briefly, orbital shaking of a subsample with chloroform/methanol/buffer in specific proportions, then recovery of total lipid in the chloroform extract. For meat, fish, shrimp, cheese and fried plantains, total fat recovery was low and/or variability was high with the unmodified assay versus results from other standard total fat methods (e.g., ether extraction, acid hydrolysis) or to CRM assigned values. Reducing the sample size or adding a homogenization step during extraction resulted in relative standard deviations of < 3% for all matrices and also values consistent with those generated by other standard total fat methods and within assigned ranges for total fat in most CRMs.

PRACTICAL APPLICATIONS

The method allows for routine batch analysis of multiple samples of a range of food types with minimized hands-on time, using commonly available laboratory equipment. The resulting total lipid extract can be subdivided for analysis of various specific lipid analytes as well as for gravimetric measurement of total fat.     

Use of Vacuum During Formation of Meat Emulsions

Meat emulsion formation under vacuum was studied in a model system and in a sausage emulsion. Sarcoplasmic and myofibrillar extracts from beef and pork infraspinatus muscle were used to compare emulsification of vegetable oil with or without vacuum. Vacuum treatment permitted more oil to be emulsified by all protein extracts. The proportional increase was greater for water-soluble than for salt-soluble extracts. Sausage emulsion was evaluated using frankfurters prepared in a vacuum chopper with or without vacuum. Product stability was improved by application of vacuum only for the entire chopping procedure. Cured color development was more rapid and more complete in the vacuum treatment. Without vacuum chopping, frankfurters showed more obvious cavitation and less density, confirming presence of air within the emulsion.     

Modification of tempeh with the addition of bakla (Vicia faba Linn)

Bakla ( Vicia faba Linn), an indigenous pulse, was subjected to fermentation by the strains of Rhizopus oligosporus either alone or blended with soybean ( Glycine max ). Mycelial growth as viewed on the surface of the fermented mass was best obtained when strain NRRL 3271 was used. Increase in moisture content and pH during fermentation was highest in the case of strain NRRL 2710 irrespective of composition of bakla-soybean mixture. The tempeh, the fermented product, in each case had a mushroom-like odour, which was independent of the strain used. Bakla and bakla-soybean (up to 1:1 ratio) tempeh was free of beany flavour but this flavour increased as the soybean content of the blend was further raised and was perceptibly high when soybean content reached 75%. Bakla tempeh was more crisp than soybean tempeh. The crispness decreased with increasing soybean content.     

EFFECTS OF "DREAM DEPRIVATION" ON DREAM CONTENT: AN ATTEMPTED CROSS-NIGHT REPLICATION.

ATTEMPTED TO REPLICATE, IN A CROSS-NIGHT DESIGN, THE FINDING THAT EARLY-NIGHT REM-SLEEP DEPRIVATION LEADS TO MORE DREAMLIKE LATE NIGHT REM-SLEEP MENTATION. 8 SS WERE REM DEPRIVED ON NIGHT 1 AND PSEUDODEPRIVED ON NIGHT 3, WHILE 8 SS WERE RUN IN THE REVERSE ORDER. REPORTS OF MENTAL CONTENT WERE ELICITED FROM NREM AND REM SLEEP ON NIGHTS 2 AND 4, SS AND "WATCHERS" COMPLETED GOUGH ADJECTIVE CHECK LISTS (ACLS) ON S BEHAVIOR DURING DAYS 2 AND 4. DEPRIVATION PRODUCED NO SIGNIFICANT CHANGES IN WAKING BEHAVIOR, NREM OR REM MENTATION, OR IN THE SLEEP CYCLE. FINDINGS ARE DISCUSSED IN TERMS OF DREAM THEORY AND METHODOLOGICAL PROBLEMS OF DEPRIVATION RESEARCH. DEPRIVATION LOWERED DAYTIME ORAL TEMPERATURE, AND ACL RESPONSES PREDICTED PSYCHOLOGICAL COMPENSATION FROM DEPRIVATION. (19 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

THE VOCATIONAL INTERESTS OF WOMEN IN PSYCHOLOGY: 1942-66.

380 FEMALE PSYCHOLOGISTS WERE ADMINISTERED THE SVIB IN 1942. IN 1966, 81% OF THE 178 WHO WERE STILL AMERICAN PSYCHOLOGICAL ASSOCIATION (APA) MEMBERS AND 275 CURRENT MEMBERS OF APA COMPLETED THE SVIB. COMPARISONS BETWEEN THE 3 PROFILES SHOWED FEW VOCATIONAL INTEREST CHANGES. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

CONTEXT CUES AS MEDIATORS: I. THREE-STAGE PARADIGMS.

TESTED THE EFFECT OF COLOR AS A MEDIATOR IN PAIRED-ASSOCIATE LEARNING IN 4 EXPERIMENTS WITH 120 STUDENTS UTILIZING STIMULUS EQUIVALENCE, RESPONSE EQUIVALENCE, AND CHAINING PARADIGMS. A COLOR WAS PRESENTED ADJACENT TO 2 DIFFERENT ITEMS IN THE LEARNING OF LIST 1. BY EXPERIMENTAL GROUPS. ITEMS COUPLED WITH THE SAME COLOR WERE PAIRED IN LIST 2. THE DIFFERENCE IN LEARNING SCORES ON LIST 2 BETWEEN THE MEDIATION PAIRS AND NEW OR CONTROL PAIRS GENERALLY INDICATED THAT MEDIATION EFFECTS OCCURRED IN THE EXPERIMENTAL GROUPS AS COMPARED TO 2 CONTROL GROUPS. (FRENCH SUMMARY) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

CAPACITY FOR SELF-DIRECTION.

A CONTENT ANALYSIS OF SELF-DESCRIPTIVE ESSAYS WRITTEN BY STUDENTS 13 OF WHOM WERE SUBSEQUENTLY SUCCESSFUL AND 11 UNSUCCESSFUL SS IN ATTAINING SELF-DIRECTED BEHAVIOR-CHANGE GOALS REVEALED: (1) HIGH-CHANGE SS MORE FREQUENTLY STATED GOALS, WITH IMPLICIT RECOGNITION THAT THE GOAL HAD NOT YET BEEN ATTAINED; (2) LOW-CHANGE SS MORE FREQUENTLY DESCRIBED THEMSELVES WITH LITTLE RECOGNITION OF ALTERNATIVE POSSIBILITIES, AND (3) LOW-CHANGE SS SHOWED MORE TENTATIVENESS AND UNCERTAINTY ABOUT THEMSELVES (IDENTITY DIFFUSION). THE FINDINGS WERE CROSS-VALIDATED IN A 2ND SAMPLE OF 9 SUCCESSFUL AND 22 UNSUCCESSFUL SS. RESULTS SUGGEST THAT SUCCESSFUL SELF-DIRECTED CHANGE IS MOTIVATED BY AWARENESS OF THE COGNITIVE DISSONANCE CREATED WHEN AN INDIVIDUAL COMMITS HIMSELF TO A VALUED GOAL THAT HE SEES AS DIFFERENT FROM HIS PRESENT BEHAVIOR. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Climate change and the response of forests

Abstract

The global climate has warmed by over 0·5°C during the last 125 years. Models of the Earth's temperature reponse to increasing levels of atmospheric carbon dioxide and other greenhouse gases estimate that the average global surface temperature will rise about 4°C by the mid twenty-first century. High latitudes will warm more than lower latitudes and winters more than summers. Forests will undergo enormous changes as temperatures increase and precipitation patterns shift. It is doubtful that forest movement will meet the rate of climate change. Many sensitive hardwood tree species, such as paper and yellow birch, sugar maple and black ash, may die. Boreal forests will replace tundra and mixed hardwood forests will replace them. Much of the change expected in the location and composition of forests may be detected by means of remote sensing.