Suprathreshold sour taste intensity and pleasantness perception with age.

Magnitude estimates for perceived intensity and pleasantness of suprathreshold concentrations of citric acid in solution and drink were examined in 180 healthy, free-living subjects divided into three groups: young (20-29 years), old (70-79 years) and very old (80-99 years). Psychophysical functions showed significant age effects. For both aqueous and food systems, the old gave higher intensity estimates to high acid concentrations and lower intensity estimates to low acid levels compared to the young and very old whose estimates were comparable. Sex had a significant effect on the intensity estimates with the women giving low acid levels lower estimates and high acid levels higher estimates than the men. All subjects gave low acid levels in solution lower intensity estimates than comparable drinks while at high concentrations, higher intensity estimates were given to solutions than drinks. Trend analysis of pleasantness estimates indicated significant age group differences. For both systems, the breakpoint, the acid level assigned the highest pleasantness estimate was lower for the young than for the elderly.

Quality characteristics of wheat-bran chiffon cakes.

Wheat bran was substituted for cake flour in chiffon cakes at 10, 20, and 30 per cent levels. Bran incorporation significantly affected (P less than 0.05) the appearance, height, and grain of chiffon cakes. Cake height decreased and cell size and cell wall thickness increased with higher levels of bran. Tenderness decreased with higher levels of bran. Compressimeter readings were higher with bran substitution at the 10 and 20 per cent levels. Sensory evaluation indicated no significant differences (P less than 0.05) between the control and 10 per cent bran cakes for moistness, flavor, and overall acceptability. Panelists did note a significant (P less than 0.05) decrease in tenderness and softness and an increase in crumbliness with higher bran levels. All chiffon cakes, regardless of bran level, were termed acceptable.

Taste perception and breast cancer: evidence of a role for diet.

Suprathreshold taste perception and nutrient intake were assessed for two groups of women aged 44 to 56 years: 24 mastectomized breast cancer outpatients and 24 matched controls. Salty and sweet taste intensity and pleasantness were evaluated in aqueous solutions and simple foods by unstructured line scaling. Dietary intakes were assessed by combined dietary recall (1 day) and food record (3 days). Suprathreshold taste intensity and pleasantness data did not differ between the breast cancer and control groups. Breast cancer subjects consumed less energy and were at greater overall nutritional risk than the controls. Compared with control subjects, breast cancer subjects were at greater risk of calcium and iron deficiency. Regression analysis was used to investigate relationships between diet and taste for a breast cancer subgroup (n = 7) with unusually low energy intake (< or = 1,300 kcal/day) and a high overall nutritional risk (25.6%). For the subgroup, significant relationships between taste and diet were found, although taste data did not differ from that of the controls. Percent risks of nutrient deficiency for vitamin B-12, thiamin, folacin, iron, and riboflavin were important predictors of taste-intensity slopes for the cancer subgroup. Findings suggest that for some of the breast cancer subjects, diet may be associated with unsatisfactory nutritional status and may be affected by suprathreshold taste perception.

Age-related olfactory and taste changes and interrelationships between taste and nutrition.

This article critically reviews the literature on age-related olfactory and taste changes and the interrelationships between nutrition and taste. Age-related taste alterations are controversial, but there is consensus on an olfactory decline with age. Much of the age-related chemoreceptive research has used inappropriate methodology, thus leaving many findings inconclusive. Changes in the taste system with age may be related to nutrient intake, which in turn can be influenced by taste. Literature on such interrelationships is limited. Vitamins A, thiamin, B-6, B-12, folacin, zinc, and copper are thought to influence taste function. Moreover, those nutrients are of concern in the aged. The use of appropriate methodology is critical not only for the sensory but also for the nutritional aspects, particularly for qualitative and quantitative assessments of nutrient intakes. This review considers the experimental deficiencies (small sample size, inappropriate age range, inadequate psychophysical and stimuli presentation procedures, and poor dietary intake assessment) of studies reported in the literature and suggests major needs for research.

Oat bran concentrate bread products improve long-term control of diabetes: a pilot study.

OBJECTIVE: To evaluate the long-term effects oat bran concentrate bread products in the diet of free-living subjects with non-insulin-dependent diabetes (NIDDM) via dietary, clinical, and biochemical methods. DESIGN: A 24-week crossover study consisting of two 12-week periods. SUBJECTS/SETTING: Eight men with NIDDM (mean age = 45 years) who lived in the community. Glucose and insulin profiles were conducted in a clinical investigation unit. INTERVENTION: Palatable, high-fiber, oat bran concentrate (soluble fiber [beta-glucan] content = 22.8%) bread products were developed. Four randomly chosen subjects ate oat bran concentrate breads first; the other subjects ate control white bread first. MAIN OUTCOME MEASURES: Dietary intake (four 48-hour dietary recalls per period) was assessed. Blood glucose and insulin (8-hour profiles) and lipid parameters after fasting were measured (at 0, 12, and 24 weeks). STATISTICAL ANALYSES PERFORMED: Analysis of variance and repeated-measures analysis of variance. RESULTS: Total energy and macronutrient intakes were similar in both periods. Mean total dietary fiber intake was 19 g/day in the white bread period and 34 g/day (9 g soluble fiber per day from oat bran concentrate) in the oat bran concentrate period. Body weight remained stable. Mean glycemic and insulin response areas (area under the curve) were lower (P < or = .05 and not significant, respectively) for the oat bran concentrate period than the white bread period. After breakfast, area under the curve for the oat bran concentrate period was lower for glucose (P < or = .01) and insulin (P < or = .05); insulin peak was reached earlier (P < or = .05) than in the white bread period. Dietary fiber intake was correlated negatively with insulin area under the curve (P < or = .05). Mean total plasma cholesterol and low-density lipoprotein cholesterol levels were lower (P < or = .01) in the oat bran concentrate period than in the white bread period. In the oat bran concentrate period, the mean ratio of low-density lipoprotein cholesterol to high-density lipoprotein cholesterol was reduced by 24% (P < or = .05). CONCLUSIONS: The well-accepted oat bran concentrate bread products improved glycemic, insulinemic, and lipidemic responses.

Effects of low voltage electrical stimulation on mature cow carcasses: Part 1-Selected quality attributes of beef.

The quality characteristics of semitendinosus (ST) and longissimus dorsi (LD) roasts obtained from mature carcasses subjected to extra low voltage (50-100 V) electrical stimulation (ES) were determined. ES was applied for 2 min with voltage increases to either 50 V (ES1) or 100 V (ESII). Evaluationss were conducted on meat obtained from control sides (no ES) aged for either 48h or 7 days and from ES carcasses aged for 48h. ES caused a reduction (P < 0·1) in pH values 1 and 4h post mortem. At 24h, the pH of each of the muscles from ES and control carcasses was similar. There were no differences in raw rib-eye muscle colour, firmness or texture due to ES. Cooking losses of ST and LD did not appear to be affected by either ES or increased ageing of control roasts. For both ST and LD roasts, trained panellists generally detected no significant effects of ES or ageing time (for no ES roasts) on palatability. Consumer panel judgements of ST roasts were similar to those of the trained judges. Water-holding capacity, tenderness (OTMS) and softness (penetrometer) data for ST and LD roasts generally support findings from sensory evaluation. Cooking and eating quality characteristics of ST and LD roasts from mature cow carcasses subjected to ES were similar to those of the controls.

Endurance-exercised growing sheep: II. Tenderness increase and change in meat quality.

A study was conducted to examine the effect, in ram lambs, of chronic treadmill exercise, on meat quality. A secondary objective was to relate changes in tenderness to metabolic and chemical phonomena. Meat quality traits, including instrumental measurements of tenderness and thaw and drip losses, were recorded for two muscles from the hind limb (semimembranosus SM; vastus lateralis, VL). Chemical analyses, including total and soluble collagen, total and myofibrillar protein, and myofibrillar fragmentation were also performed. Muscles from exercised sheep were significantly more tender than muscles from their control counterparts. A larger myofibrillar protein to total collagen ratio was observed in the VL muscles from exercised sheep (P < 0·01) which probably contributed to the observed increase in tenderness. However, similar results were not observed for the SM muscle. The tendency for a slightly higher pH at similar post-mortem temperatures in meat from exercised sheep may also have contributed to the increased tenderness.

Studies of extra low voltage electrical stimulation of mature beef carcasses.

The quality characteristics of biceps femoris (BF) and semimembranosus (SM) roasts obtained from mature cow carcasses treated with a commercial extra low voltage (30 V) electrical stimulation (LVES) system were determined. LVES was applied for either 2 (ESII) or 4 min (ESIII). Evaluations were conducted on meat obtained from control sides (no ES) aged for either 48 h (Ia) or 7 days (Ib) and from ES sides aged 48 h. ES caused a reduction (P<0·001) in pH values at 2 and 6 h post mortem. At 24 h, the pH of muscles from all carcasses was about 5·5. ES duration did not influence muscle pH. Rib-eye muscle colour for ESII and ESIII carcasses was lighter and brighter (P<0·05) than that of control carcasses. Generally stimulated BF roasts had greater cooking losses than control Group Ib roasts; SM roasts from ES carcasses had lower losses than comparable to Group Ib roasts. ES duration had no effect on per cent cooking losses. Trained panelists generally detected few significant effects in BF roasts due to ES. Warner-Bratzler data indicated that ESII and ESIII BF roasts were similar and significantly more tender than comparable control Group Ib samples: OTMS data indicated that all BF roasts were similar in tenderness. However, SM roasts from ES carcasses were judged more soft (Groups II and III) and tender (ESII) than comparable control roasts. Instrumental measurements of tenderness for SM roasts tended to support the taste panel results. Generally, duration of LVES had no effect on the eating quality of either BF or SM roasts. Since LVES effects on the palatability of SM roasts were evident but the effects of stimulation of BF roasts were few, further studies of this LVES system are needed before its use can be recommended. Generally, increasing post-mortem ageing time for mature control carcasses did not influence either BF or SM roast quality.

Identification of PSE in the Longissimus muscle of pigs stunned by captive-bolt.

Meat quality characteristics in the longissimus muscle of 57 pigs slaughtered at approximately 100 kg liveweight were studied. They were slaughtered by captive-bolt stunning and exsanguination. The incidence of pale, soft and exudative (PSE) meat was identified by muscle colour and water holding capacity 24 h post mortem (C(24) and WHC(24)). The muscle pH value 45 min post mortem (pH(1)), absorption ratio (R-value) of muscle acid extract, and colour and water holding capacity 1 h post mortem (C(1) and WHC(1)) were also determined. The interrelationships among pH(1), R-value, C(1), WHC(1), C(24) and WHC(24) were studied and the multiple regressions of C(1), C(24), WHC(1) and WHC(24) with pH(1) and R-value were computed. The results of simple and multiple regression analysis showed that neither muscle pH(1) nor R-value could effectively predict colour or WHC at 24 h post mortem. Combining pH(1) and R-value provided little improvement in the prediction of the ultimate meat colour and WHC.

Protein-energy malnutrition in low income elderly Nairobi women.

Nutritional data for two groups of low income elderly women (chi = 64, range 57-74 years) in Nairobi, Kenya were compared. Group I (n = 113), slum dwellers, had an income of < or = $20 Cd per month; Group II (n = 88), poor urban area inhabitants, had an income of < or = $170 Cd per month. Dietary intakes were assessed quantitatively by four 24-h dietary recalls; anthropometric and biochemical data were obtained. Twenty-one women (16% of Group I; 3% of Group II) were classified as having protein-energy malnutrition (PEM) based on abnormal anthropometric measurements or low serum albumin concentration. The malnutrition was marasmic-like; the anthropometric measurements (body weight, triceps, skinfold thickness (TSF), mid-arm muscle circumference (MAMC) of the PEM Group were lower (P < or = 0.05) than those of Groups I and II. The PEM Group was older (chi = 68 years), had lost more teeth, and had more subnormal values than Groups I and II for: serum albumin, hemoglobin, hematocrit, MCHC, MCH, serum transferrin and serum iron. Inferior diets were a contributing factor. Mean energy and protein intakes of the PEM Group were low: 1471 kcal day(-1) (26 kcal kg(-1)) and 42 g day(-1) (0.79 g kg(-1)) respectively. The main protein sources were vegetables (48%) and cereals (36%); only 6 g protein was of high quality. Group II mean protein and energy intakes were greater (P < or = 0.05, P < or = 0.01) than those of the PEM Group and mean dairy product intake was higher (P < or = 0.001). The PEM Group and Group I had low mean energy intakes and an unsatisfactory dietary pattern; they consumed less meat (P < or = 0.01) and less fat (P < or = 0.001) than Group II. For the PEM Group dietary intakes of energy, fat and sugar were significantly correlated with TSF and MAMC; for the PEM Group monthly income was significantly correlated with weight, BMI, TSF and MAMC. Data suggest that elderly women living in Nairobi slums are at high risk of malnutrition, one of the factors contributing to the problem is inadequate food intake.