Consumer acceptance of foods lower in sodium.

OBJECTIVE: To assess the magnitude of sodium reduction that can be made without significantly changing the perception of saltiness and acceptability of a broad range of common food items. DESIGN: The investigation was carried out in two phases. Military and civilian volunteers (N = 190 in study 1; N = 380 in study 2) from the US Army Natick Research, Development and Engineering Center rated the saltiness and acceptability of foods containing differing sodium concentrations. SETTING: Consumers rated food items in the sensory testing laboratory. INTERVENTION: "Regular" and "low-sodium" entrees were rated for saltiness and acceptability in study 1. Prepared food, commercially prepared food, and beverages containing various concentrations of sodium were rated for saltiness and acceptability in study 2. STATISTICAL ANALYSES PERFORMED: Results were analyzed using Pearson correlation coefficients, Student's t test, and analysis of variance. RESULTS: The perception of saltiness increased as the concentration of sodium increased. Acceptance ratings varied considerably over a broad range of sodium concentrations, which indicates that the relationship was product specific. Results suggest that a reduction of one third or more in added sodium can be made to some foods without significantly affecting consumer acceptance. APPLICATIONS: The sodium content of food can be reduced by consumer-guided food engineering and food preparation. Alterations in food preparation and product formulation, in conjunction with alterations in diet, can be effective methods for reducing sodium consumption.

Role of sensory and cognitive information in the enhancement of certainty and liking for novel and familiar foods.

Expected and actual liking for novel and familiar foods were examined under various conditions of sensory and verbal information with 121 subjects who differed in food neophobia. The possible mediating roles of uncertainty about product identity and resemblance to familiar foods were also investigated. Subjects were divided into three verbal information groups (no information; product name; ingredient and use information) balanced for neophobia, age and gender. All groups rated test samples under three sensory conditions: (1) appearance only, (2) appearance and smell and (3) appearance, smell and taste. Neophilics rated novel foods more favorably than did neophobics. Accumulating sensory experience (appearance, smell, taste) decreased liking for novel foods but increased liking for familiar foods. Verbal information generally increased liking for all samples. Liking and certainty of product identity were curvilinearly related for novel foods, but linearly related for familiar foods. Liking for products judged to closely resemble the test product predicted up to 64% of the variability in expected and actual liking. Eight weeks later, subjects rated one of the two novel foods higher than in the first exposure, but no other exposure effects were observed. Our data suggest that information (possibly via reduced uncertainty), resemblance to more familiar foods, and exposure contribute to reducing initially negative responses to novel foods; furthermore, neophobia decreases liking for novel foods similarly at all levels of sensory input (visual, smell and taste).

Antecedents and consequences of expectations related to fat-free and regular-fat foods.

Hedonic and sensory expectations related to fat-free and regular-fat pound cake, crackers and American cheese were studied with 97 subjects divided into three subgroups, each testing one type of product. Four study phases were separated by 1-month intervals: (1) a questionnaire on demographics, dietary practices and consumption of the test products, (2) intensity ratings of sensory attributes and ratings of liking of unlabeled fat-free and regular-fat samples, (3) ratings of expected attribute intensities and liking in response to product labels of "fat-free" and "regular", and subsequent ratings of these samples and (4) phase 3 repeated with opposite (incorrect) labels. Fat-free products were expected to be less liked than their regular counterparts; however, only cheese was less liked in actual taste tests. Expected liking was best predicted by familiarity with the product and, in the case of fat-free products, by the extent to which a person substituted low-fat for high-fat foods. Actual liking was best predicted by the effect of labeling and by expectations. The expected intensities of sensory attributes were uniformly higher in regular than in fat-free products. Both sensory and hedonic ratings of labeled samples changed in the direction of expectations, as compared to baseline values, supporting an assimilation model of the effect of disconfirmed expectations on sensory perception and consumer acceptance.

Nutrient, waste management, and hygiene systems for chemical protective suits.

Current United States military chemical protective ensembles do not provide for feeding, removing body wastes, or ensuring the hygiene of troops operating in a contaminated environment. As part of a nuclear-biological-chemical life support demonstration program, systems were developed to provide these capabilities. The nutrient system consisted of foods packaged in tube dispensers and a delivery system compatible with North Atlantic Treaty Organization respirators. The waste management/hygiene systems consisted of waste collection and hygiene items incorporated into a retractable-arm suit design with integrated airlock. A field demonstration of the systems resulted in successful use by armored vehicle personnel, high, positive user feedback, and only minor functional problems.

Effects of age and removable artificial dentition on taste.

Sodium chloride and sucrose gustatory recognition thresholds, suprathreshold taste intensity function, and sucrose suprathreshold taste preference in healthy adult males with removable artificial dentition were compared with persons having natural dentition. In addition, several inorganic salivary constituents were evaluated for their possible relationship with these modalities. The 75 participants studied were divided into two age and two dentition groups: less than 65 years versus 65 years and older; and natural dentition only versus either removable partial dentures or complete artificial dentition. Recognition threshold and suprathreshold psychophysical functions were assessed using aqueous solutions of sodium chloride and sucrose. Suprathreshold hedonic judgments were also determined for sucrose. Samples of stimulated parotid saliva were analyzed for sodium, potassium, and bicarbonate. As age increased, a statistically significant decrease was noted in the exponent of the psychophysical function for sodium chloride. A similar, but nonsignificant, trend was observed for sucrose, which was complicated by an interaction between age and dentition status. For sodium chloride, recognition thresholds tended to be higher for older persons with removable partial and complete dentures. However, no statistically significant effect was observed on the sucrose threshold or hedonic response as a result of dentition status. Analysis of several parotid saliva constituents showed no statistically significant effect caused by age or dentition status and correlations noted among the psychophysical measures appeared to be fortuitous.

Health care providers' attitudes toward nutrition.

A survey questionnaire, assessing general attitudes toward the importance of nutrition in the prevention of disease and the maintenance of good health, was administered to physicians, nurses, dentists, and technicians at five U.S. Army medical centers. The various groups of health care specialists differed significantly on many items concerning the importance of good nutrition and eating habits for maintenance of good health and for recovery from illness, as well as on items concerning the importance of nutrition knowledge and training in their health care professions. More agreement was found among the groups on items concerned with the relationship between disease states and dietary factors and the effectiveness of health education programs in the prevention of various diseases. Self-reports of personal health habits did not correlate with scores on survey items concerned with the importance of good nutrition, suggesting that personal attitudes toward nutrition may be unrelated to other health practices.

Reaction time and visual brightness: within-subject correlations.

An experiment was conducted to compare visual reaction time and visual brightness within the same subjects. Simple reaction times and magnitude estimates of brightness were obtained in response to 1000-msec. flashes of 60.7, 67.5, 76.4, 85.1, and 93.4 dB re 10(-10)L white light. The relationship between reaction time and stimulus intensity was best described by a negative logarithmic function, while the relationship between magnitude estimates of brightness and stimulus intensity was best described by a power function. Linear correlations between reaction times and magnitude estimates indicated that visual reaction time and brightness are not proportional within all subjects. Previous reports of proportionality between these two measures were discussed as possibly being the result of inappropriate cross-experiment comparisons.

Chemical stimulation of single human fungiform taste papillae: sensitivity profiles and locus of stimulation.

Psychophysical responses to chemical stimulation of single human fungiform taste papillae were obtained from 40 papillae in four subjects. Effects of solution concentration and locus of stimulation were examined for nine test compounds. Sensitivity profiles constructed for individual papillae showed that single fungiform papillae mediate more than a single taste quality. In addition, the chemical sensitivities of individual papillae were reflected in their thresholds for all compounds, and correlation coefficients between recognition thresholds were no greater for similar than for dissimilar tasting compounds. No differences in mediation of quality were found as a function of locus of stimulation on the papilla, although sensitivity was found to be greater on the dorsal surface than on the sides. The data were discussed within the context of previous studies of response characteristics of single papilla.