THREE SCALING METHODS FOR CONSUMER RATING OF SALT INTENSITY

This study aimed to identify a scaling technique, which would offer the greatest degree of discrimination and accuracy in an evaluation of soup samples, varying in salt concentration (0.3, 0.8 and 1.3% salt). A Seven Point Category Scale, a 100 mm Line scale and non-modulus Magnitude Estimation were used to evaluate samples by consumers (n = 36).
A Friedman Two-Way ANOVA and a Wilcoxon Signed Ranks test were applied to the data to compare discriminatory ability and accuracy of the scaling techniques. Results revealed that each of the techniques could be used to discriminate between samples (P<0.001). However, none of the three techniques were significantly more accurate than one another. In view of the results and consumer preference/comments for using the Seven Point Category Scale, this technique is proposed as an effective method for consumer rating of salt intensity.     

THE RELATIONSHIP OF FIBER TO SENSORY SPECIFIC SATIETY1

The objective of this study was to determine if higher fiber levels in a food contributed to greater sensory specific satiety. Thirty-two subjects tasted and rated their liking of small samples of nine foods (including the test food) before and after a test meal. Test meals consisted of 500 kcal (2092 kJ) of a soup or a muffin. Both a high-fiber (10g) and low-fiber (1g) version of a soup and a muffin were tested. High-fiber versions contained added microcrystalline cellulose. Data from the soup and muffin treatments were analyzed separately. Each of the test meals resulted in a greater decrease in liking for the food eaten versus the uneaten foods. However, there was no increase in sensory specific satiety for the high-fiber treatments versus the low-fiber treatments. There was also no main effect for gender.     

The effects of the distribution of training on learning feedback-assisted cardiac acceleration

In order to test a hypothesis derived from a motor skills learning model of cardiac acceleration control, groups of subjects were given biofeedback training for four sessions to learn cardiac acceleration under four different training schedules: (1) all sessions in one day, (2) daily sessions, (3) sessions every other day, and (4) weekly sessions. Ability to accelerate heart rate both with and without feedback was determined at each session. Also ability to accelerate heart rate without feedback was determined 1 week after the last training session as a measure of retention. Although there was highly significant (p less than.0001) evidence of heart rate control both with and without feedback, there were no differences in degree of control attributable to distribution of training sessions. There was, however, a trend (p less than .10) for subjects trained under the most distributed training schedule (weekly) to show more retention than subjects trained under a less distributed schedule (daily).     

LIKING FOR ICE CREAM MEASURED WITH THREE PROCEDURES: SIDE-BY-SIDE, AFTER CONSUMPTION AND SINGLE SAMPLES

The purpose of this study was to compare how similar results are achieved by three different procedures of measuring liking for ice cream. Subjects (N=56) assessed their liking for three brands of vanilla ice cream on a 9-point scale in seven sessions within three weeks. The examined procedures were (1) tasting and rating all three brands simultaneously side-by-side within the same session, (2) rating each brand in separate sessions after ad libitum consumption and (3) tasting (without consumption) and rating each brand in separate sessions. The liking scores for brands differed significantly but the differences were small because all samples were well-liked. In all procedures, the ratings of liking differed clearly between those who ranked the brand first and those who ranked it second or third, even if there was a considerable number of tied first places. Correlations among the three different measurements of liking were relatively low for all brands of ice cream (r = 0.16 – 0.37). The most preferred brand for most respondents changed from one procedure to another. The perceived characteristics were close to ideal in all brands, and all three procedures gave similar mean results. The distance of mouthfeel, creaminess, sweetness, and vanilla aroma from ideal differed between those who liked the brand best and those who rated it second or third. These differences were larger in side-by-side and after consumption conditions compared to single sample presentation.     

LIKING OF POPCORN CONTAINING DIFFERENT LEVELS OF SALT1

Approximately 300 subjects participated in a test to determine whether the level of salt in popcorn affected the change in overall liking observed as a consequence of consuming a serving of popcorn. Subjects tasted and rated three samples of popcorn (low, medium, high salt levels), ate a serving of popcorn at one of the salt levels and then tasted and rated the three samples again. Subjects returned one or seven days later and tasted and rated the samples again. Overall liking, salt intensity and salt liking were measured. The subjects also completed a questionnaire about their liking and consumption of popcorn. Liking scores for the popcorns decreased after eating a 3-cup serving; however, sensory specific satiety for the different levels of salt was not observed. Consuming low salt popcorn increased the rated saltiness of the popcorns, whereas consuming high salt popcorn decreased the rated saltiness — probably a frequency effect. When subjects retasted the popcorns one or seven days later, all liking ratings increased except the salt liking ratings for the high salt sample. There was also a trend for the overall liking of this high salt sample to increase less than for the medium and low salt samples. Questionnaire measures of liking or consumption were not related to the changes in liking observed.     

A COMPARISON OF TASTE TEST RATINGS,REPEATED CONSUMPTION,AND POSTCONSUMPTION RATINGS OF DIFFERENT STRENGTHS OF ICED TEA1

One objective of this study was to compare taste test ratings with amounts consumed and postconsumption ratings made as iced teas of different strengths were repeatedly consumed. The second objective was to determine whether sensory specific satiety could be used as a rapid indicator of long term acceptability of the teas. Subjects first rated their liking of and the flavor intensity of several samples of lemon flavored iced tea. Two tea concentrations were selected from this test to represent distinctly different flavor intensities. Taste test liking ratings of the strong concentration were higher than those of the weak concentration. Subjects consumed either the strong or the weak iced tea ad lib on 20 different afternoons over a 2-month period and rated their liking of the tea after each session. We measured the amount of tea consumed each time. On repeated consumption the subjects liked the weaker tea better than the stronger tea. Subjects consumed about the same amount of each tea. A different group of 15 subjects participated in a sensory specific satiety study of the same two teas. Those subjects drank more of the weak tea than the strong tea.     

MOST PREFERRED LEVEL OF SUGAR: RAPID MEASURE AND CONSUMPTION TEST

This study dealt with the determination of the most preferred level of sugar in plain yoghurt. Twenty-four consumers participated in 13 lab meals. The results of a rapid test, based on ideal relative-rating were compared to the results of a consumption test, based on the amount of test product consumed, in order to assess if this rapid test predict actual consumption behavior. Linear regression of the ideal-relative intensity ratings on logarithms of sucrose concentrations was used to estimate, for each subject, ideal-point (i.e., sucrose level corresponding to a null distance from ideal) and slope (which accounts for tolerance) with a good reproducibility. The consumption tests revealed behavior which could not be related to the level of sugar for 30% of the subjects. Moreover, the most preferred level of sugar obtained with the rapid test was not always the most consumed. However, the two mean values of ideal level are close: 6.3% with ideal-relative rating, and 7.5% with measurement of eaten quantity. Thus our experimentation underlines the interest of ideal-relative rating as a good predictor of consumption behavior.     

Obese Women Have Lower Monosodium Glutamate Taste Sensitivity and Prefer Higher Concentrations Than Do Normal‐weight Women

The goal of this study was to determine whether obese women exhibit altered umami and sweet taste perception compared to normal‐weight women. A total of 57 subjects (23 obese and 34 normal weight) participated in a 2‐day study separated by 1 week. Half of the women in each group were evaluated using monosodium glutamate (MSG; prototypical umami stimulus) on the first test day and sucrose on the second test day; the order was reversed for the remaining women. We used two‐alternative forced‐choice staircase procedures to measure taste detection thresholds, forced‐choice tracking technique to measure preferences, the general Labeled Magnitude Scale (gLMS) to measure perceived intensity of suprathreshold concentrations, and a triangle test to measure discrimination between 29 mmol/l MSG and 29 mmol/l NaCl. Obese women required higher MSG concentrations to detect a taste and preferred significantly higher MSG concentrations in a soup‐like vehicle. However, their perception of MSG at suprathreshold concentrations, their ability to discriminate MSG from salt, and their preference for sucrose were similar to that observed in normal‐weight women. Regardless of their body weight category, 28% of the women did not discriminate 29 mmol/l MSG from 29 mmol/l NaCl (nondiscriminators). Surprisingly, we found that, relative to discriminators, nondiscriminators perceived less savoriness when tasting suprathreshold MSG concentrations and less sweetness from suprathreshold sucrose concentrations but had similar MSG and sucrose detection thresholds. Taken together, these data suggest that body weight is related to some components of umami taste and that different mechanisms are involved in the perception of threshold and suprathreshold MSG concentrations.     

A comparison of trace-elemental composition of natural color and gray hair

In order to get some information on the possible causes of graying of hair, we have used the technique of X-ray fluorescence (XRF) analysis for comparing the trace element contents of natural color and gray hair from a number of subjects. The technique of XRF was preferred to other analytical methods for this kind of comparative studies since it appeared to be simple, convenient, quick, and contamination free. Natural color and gray hair from each subject were obtained from the same scalp region. The hair samples were washed in the recommended fashion. The natural color and gray hair from different subjects were mounted separately on hollow plastic cylindrical sample holders, assuring that the hair were parallel to, and not on top of one another. The samples were analyzed in a commercial wave length dispersive XRF system, with different X-ray tubes being used for obtaining maximum sensitivity for different elements. The scattered X-ray peak from each sample was also monitored and gave a measure of the sample volume being investigated. So far, hair samples from 10 subjects have been analyzed. Their results are presented in the paper, and advantages of XRF, for trace element analysis on hair are discussed.     

An Investigation of <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis> in Rectal-Collected Fecal Samples of Cows

In order to better understand the range and role of Bacillus thuringiensis (Bt) and its toxins in nature, we have undertaken a study of Bt taken directly from the rectum of 117 cows from 37 farms on the Caribbean island of Trinidad. Thirty-seven fecal samples (32%) were found to contain at least one Bt. Generally only one or two isolates with a particular crystal morphology were isolated from any one sample, however, a few samples contained more, up to 11 isolates, suggesting post-ingestion amplification. Bioassays using larvae of Musca domestica, Caenorhabditis elegans and Tetrahymena pyriformis showed no observable toxicity in gross bioassays. Very small dot-like parasporal bodies, not generally characteristic of Bt, were isolated from 44% of the samples, which in many instances appeared unstable and whose relation to Bt Cry protein-containing parasporal bodies is unknown. In conclusion, we find little evidence for a host adapted strain of Bt in the cows examined, nor toxicity to organisms that might logically be associated with either the cow or its feces. The presence of a large number of isolates containing small dot-like parasporal bodies, possibly either poly-β-hydroxybutyrate storage bodies or Cry proteins, was unexpected and merits further investigation.     

Urinary Sodium Excretion and Dietary Sources of Sodium Intake in Chinese Postmenopausal Women with Prehypertension

Background

Reducing salt intake in communities is one of the most effective and affordable public health strategies to prevent hypertension, stroke and renal disease. The present study aimed to determine the sodium intake in Hong Kong Chinese postmenopausal women and identify the major food sources contributing to sodium intake and urine excretion.

Methods

This was a cross-sectional study among 655 Chinese postmenopausal women with prehypertension who were screened for a randomized controlled trial. Data collection included 24 h urine collection for the measurement of sodium, potassium and creatinine, 3-day dietary records, anthropometric measures and questionnaire survey on demographic data and dietary habits.

Results

The average salt intake estimated from urinary excretion was 7.8±3.2 g/d with 82.1% women above WHO recommendation of 5 g/day. Food groups as soup (21.6%), rice and noodles (13.5%), baked cereals (12.3%), salted/preserved foods (10.8%), Chinese dim sum (10.2%) and sea foods (10.1%) were the major contributors of non-discretionary salt. Discretionary salt use in cooking made a modest contribution to overall intake. Vegetable and fruit intake, age, sodium intake from salted foods, sea foods and soup were the independent determinants of urinary sodium excretion.

Conclusions

Our data revealed a significant room for reduction of the sodium intake. Efforts to reduce sodium from diets in Hong Kong Chinese postmenopausal women should focus on both processed foods and discretionary salt during cooking. Sodium reduction in soup and increase in fruit intake would be potentially effective strategy for reducing sodium.     

Taste perception and diet in individuals with Chinese and European ethnic backgrounds

Relationships between taste perception and diet were investigatedin two ethnic groups. The Chinese subjects (n = 30) were bornin the People's Republic of China and were currently livingin the United States. The U.S. subjects (n = 30) were of Europeanancestry. Psychophysical taste intensity functions for sucrosesolutions, NaCl solutions and NaCl in soup were obtained usingmagnitude matching. Pleasantness ratings for the above stimuli,plus sucrose in cookies and NaCl in crackers were obtained usingcategory rating scales. Three-day dietary records and the frequencyof sweet food consumption were also collected. Chinese subjectsassigned higher pleasantness ratings to the higher concentrationsof sucrose in water and showed a tendency to rate sucrose incookies as tasting more pleasant. These higher pleasantnessratings of sucrose were not reflected in increased sugar intake.The Chinese subjects also assigned higher pleasantness ratingsto and preferred higher concentrations of salt in crackers andthis was reflected in the data from the dietary records. TheChinese Na/Kcal and Na/K ratios were greater than those of theU.S. group.     

Leucine supplementation does not enhance acute strength or running performance but affects serum amino acid concentration

This study described the effect of leucine supplementation on serum amino acid concentration during two different exercise sessions in competitive male power athletes. The subjects performed a strength exercise session (SES; n = 16; 26 +/- 4 years) or a maximal anaerobic running exercise session (MARE; n = 12; 27 +/- 5 years) until exhaustion twice at a 7-day interval. The randomized subjects consumed drinks containing leucine (100 mg x kg/body weight before and during SES or 200 mg x kg/body weight before MARE) or placebo. Blood specimens taken 10 min before (B) and after (A) the sessions were analyzed for serum amino acids. In SES the concentration of leucine was distinctly higher in the leucine supplemented group than in the placebo group in both B (p < 0.001) and A (p < 0.001) samples. The leucine concentration decreased in placebo but not in the leucine supplemented group following the exercise session. Isoleucine (p = 0.017) and valine (p = 0.006) concentration decreased more in the leucine supplemented group than in placebo in A samples. In MARE the concentration of leucine was higher in the leucine supplemented group than in placebo in both B (p < 0.001) and A (p < 0.001) samples and increased (p < 0.001) in the supplemented group following the session. Isoleucine (p = 0.020) and valine (p = 0.006) concentration decreased in the supplemented group in A samples. There were no differences in a counter movement jump after SES or in the running performance in MARE between the leucine supplemented group and placebo. These findings indicate that consuming leucine before or before and during exercise sessions results in changes in blood amino acid concentration. However, the supplementation does not affect an acute physical performance.     

EFFECTS OF YEAST,FERMENTATION TIME,AND PRESERVATION METHODS ON TARHANA

The physicochemical properties of tarhana soup produced with different dough treatments, fermentation times, and preservation methods were examined. Tarhana doughs were prepared with yogurt (control) or baker's yeast (Saccharomyces cerevisiae) and fermented for 3 days. Samples were taken at 24, 48, and 72 hr. Samples were then preserved via one of four methods: sun dried, dried in the shade, vacumn dried, and frozen. Frozen samples produced lower organic acid levels after 72 hr of fermentation in both control (0.68 g/100 g) and yeast (0.61 g/100 g) applications than samples that were dried (0.94 g/100 g control samples; 0.81 g/100 g samples with yeast). Increasing fermentation time resulted in a significant effect on the formation of organic acid in the tarhana (p < .01). At 72 hr of fermentation, total acidity increased 11%, 17%, and 23% for tarhana samples vacumn-dried, sun-dried, and dried in the shade, respectively. Preservation methods also affected the moisture, ash, crude protein, total acidity, pH, salt, fat, reducing sugar levels, and the sensory assestment of tarhana soup (p < .01). Sensory characteristics were not significantly affected by baker's yeast in any of the preservation methods used (p > .01). However, sensory scores for tarhana prepared from the samples dried in a sheltered area showed a reduction in color desireablilty as the fermentation time increased. The soup prepared from frozen tarhana (72 hr fermentation, with yeast) had the highest scores with respect to color, mouth feel, flavor, and overall acceptability. Vacuum-dried samples' scores in these areas were also high in comparison to the two other drying methods.     

Habitation and recovery of vascular responses in calf and forearm and of the level of pain sensation during the cold pressor test in man

Forearm and calf blood flow were measured using a mercury-in-silastic gauge during immersion of one foot in water at 4 degrees C. The subjects were asked to assess the level of pain on a scale 0-10. The effects of one session of repeated immersions on the vascular response in the calf, forearm and on subjective pain sensation were studied. In 6 of the 14 subjects vasodilatation was elicited in both forearm and calf during the first immersion. During the first session the vasodilation diminished, while subjective pain sensation remained at the level of 7 on the scale. In 4 subjects vasoconstriction in both calf and forearm occurred during the first immersion. During repeated immersions forearm vasoconstriction subsided, while in the calf it remained at the same level. The level of the subjective pain sensation diminished from 7.5 to 5 in 1 subject. Repeated immersions in six to ten daily sessions led to reduction of vasodilatation in calf and forearm while there was a small change in the pain sensation, i.e. reduction from the level of 6.9 to 5.7 (P less than 0.01). In subjects in whom vasoconstriction in forearm and calf was observed no clear trend in vascular responses was observed during the repeated daily sessions while the pain sensation in 1 subject was reduced from 6 to 4.8. In 3 subjects the change of vascular responses was different in the forearm and calf.(ABSTRACT TRUNCATED AT 250 WORDS)     

Does acute exposure to mobile phones affect human attention?

Recent studies have indicated that acute exposure to low level radiofrequency (RF) electromagnetic fields generated by mobile phones affects human cognition. However, the relatively small samples used, in addition to methodological problems, make the outcomes of these studies difficult to interpret. In our study we tested a large sample of volunteers (168) using a series of cognitive tasks apparently sensitive to RF exposure (a simple reaction task, a vigilance task, and a subtraction task). Participants performed those tasks twice, in two different sessions. In one session they were exposed to RFs, with half of subjects exposed to GSM signals and the other half exposed to CW signals, while in the other session they were exposed to sham signals. No significant effects of RF exposure on performance for either GSM or CW were found, independent of whether the phone was positioned on the left or on the right side.     

Effects of post-ingestion and physical conditions on PCR amplification of host blood meal DNA in mosquitoes

The effects of post-ingestion and physical conditions under which killed mosquitoes are stored on the success of detecting blood meal DNA of Anopheles stephensi and Culex quinquefasiatus were investigated by polymerase chain reaction (PCR) amplification at the human mitochondrial DNA cytochrome b (cytB) gene. Host DNA extracted from the blood meal up to 33 h post-ingestion in both species acts as an efficient template for PCR amplification. However, more DNA concentration is needed for meals digested for a longer time, and successful PCR amplification from meals digested for 36 h,dropped to a faint band. There were no differences between PCR success rate for samples stored at +4 or -20 degrees C, but less successful products were observed in samples kept at 4 degrees C for the periods longer than 30 h digestion. The results of this study are important for conducting malaria epidemiological studies that provide information about the degree of contact between human hosts and mosquito vectors, impact of vector controls such as bed nets and repellents, and the transmission dynamics of human malaria and other vector-borne diseases.     

Studies on generalized kinetic model and Pareto optimization of a product-driven self-cycling bioprocess

The aim of this study is the optimization of a product-driven self-cycling bioprocess and presentation of a way to determine the best possible decision variables out of a set of alternatives based on the designed model. Initially, a product-driven generalized kinetic model, which allows a flexible choice of the most appropriate kinetics is designed and analysed. The optimization problem is given as the bi-objective one, where maximization of biomass productivity and minimization of unproductive loss of substrate are the objective functions. Then, the Pareto fronts are calculated for exemplary kinetics. It is found that in the designed bioprocess, a decrease of emptying/refilling fraction and an increase of substrate feeding concentration cause an increase of the biomass productivity. An increase of emptying/refilling fraction and a decrease of substrate feeding concentration cause a decrease of unproductive loss of substrate. The preferred solutions are calculated using the minimum distance from an ideal solution method, while giving proposals of their modifications derived from a decision maker’s reactions to the generated solutions.     

CONSUMER ACCEPTABILITY OF VEGETABLE SOUPS

The aim of this study was to investigate whether product label information “produced with organic ingredients” and “stabilization technology” affects consumer acceptability of vegetable soups. Three focus group interviews were preliminarily conducted in order to gain information about the appropriate terminology to use in the next consumer test. In all, 109 subjects were recruited by means of a background questionnaire. They were then divided into three groups according to age, gender and soup preference. Each group evaluated three different types of soup in two phases, first blind and then with information. At the end of the second phase, the participants filled in a conjoint analysis questionnaire. The results demonstrated that if consumers were informed that soup is prepared with organic ingredients, they would improve their acceptability scores, whatever the soup type. Stabilization technology information had no effect. Conjoint results revealed that consumers appreciate soups made with organic legumes and cereals and without seasoning. However, differences among subgroups were found.