Relationship Between Relative Humidity and Moisture Loss in Dry Aged Beef

ObjectivesThe objective of this research was to assess the impact of low relative humidity (RH) during dry aging on moisture and trim loss, tenderness, and flavor. The working hypothesis was that rapid drying would create a hard crust on the meat surface that could reduce moisture release over time, thereby reducing weight loss, enhancing tenderness (by retaining more water), and altering flavor when compared to dry aging at higher RH.Materials and MethodsSixteen USDA low Choice boneless strip loins were assigned to one of the four aging treatments: vacuum (Wet), dry-aging at 50% RH (RH50), dry-aging at 70% RH (RH70), or dry-aging at 85% RH (RH85). Loins were placed in individual dry aging chambers and aged for 42 d at 1°C and 2200 RPM fan speed. A computerized dry aging system was designed and built that is capable of measuring and precisely controlling RH (± 1%), temperature (± 0.5°C), and air velocity (± 0.1m/s). The chambers have built-in weighing scales that can continuously monitor weight loss (± 5 g). All measured data can be saved on the connected computer in intervals of 1 s. After aging, loins were trimmed of dehydrated fat/lean and evaluated for trim loss. Loins were fabricated anterior to posterior, cut into steaks and evaluated for water activity (aw), Warner-Bratzler shear force (WBSF), and by sensory analysis to detect flavor differences via triangle test (n = 32). Rate of moisture loss was analyzed as a split plot design with treatment as the main plot and days of aging as the repeated measures. All the other data were analyzed as a completely randomized design. Chamber (loin) was considered the experimental unit. Data were analyzed using the PROC GLIMMIX procedure of SAS with α = 0.05.ResultsThere was a treatment by day interaction for rate of moisture loss (P < 0.001). A faster rate of moisture loss was found for RH50 when compared to RH85 on the first day of aging (P < 0.001), while RH70 was intermediate. Loins dry-aged at RH50 and RH70 had higher rates of moisture loss than RH85 on Days 2 and 3 of aging (P < 0.05). By Day 4, no differences in rate of moisture loss among RH treatments were found (P > 0.05). Wet-aged samples had lower moisture loss (P < 0.001), trim loss (P < 0.001) and higher yield (P < 0.001) than all dry-aged treatments. However, there were no differences among RH treatments for total moisture loss (P > 0.05), trim loss (P > 0.05) and yield (P > 0.05). Steaks from dry-aging treatments had lower aw values (P < 0.001) than steaks from the Wet group. No differences in aw values among RH treatments were found (P > 0.05). There was a location effect for aw values. Samples from the ventral region of the steak had lower aw values than samples from the central and dorsal region (P < 0.001). There were no differences among treatments for WBSF (P > 0.05). Results from the triangle test indicated that there was a detectable difference between Wet and RH70 (P < 0.05). However, there was no detectable difference between RH50 and RH85 (P > 0.05).ConclusionResults suggest that no such case hardening effect occurs when dry aging beef, even when the RH was kept very low (50%) and the total weight loss was 23%. Instead, the lower RH results in more rapid moisture loss at the beginning of the aging process without significantly affecting the total amount of moisture loss. Trim loss, yield, tenderness and flavor were not affected by relative humidity during dry aging.

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Dry Aging of High Ultimate pH Beef

Meat and Muscle Biology ◽

10.22175/mmb.10746 ◽

2019 ◽

Vol 3 (2) ◽

Author(s):

F. A. Ribeiro ◽

S. K. Lau ◽

N. Herrera ◽

M. Henriott ◽

N. Bland ◽

...

Keyword(s):

Lipid Oxidation ◽

Repeated Measures ◽

Moisture Loss ◽

Ph Effects ◽

Triangle Test ◽

Split Plot ◽

Trim Loss ◽

Retail Display ◽

Tbars Values ◽

Plot Design

ObjectivesDry aging is a process in which water is removed from the meat by evaporation. As meat loses water, the flavor compounds are concentrated, resulting in stronger flavor. Meat pH may be important when dry aging as it relates to the ability of muscle to bind water. Therefore, this study aimed to evaluate pH effects on water loss when dry aging and the effects on meat quality characteristics. Dry aging of dark cutting (DC) beef may improve flavor and increase yield.Materials and MethodsSix USDA low Choice and six dark cutting (DC) carcasses with the same degree of marbling were selected and boneless strip loins from both sides were obtained. Longissimus muscle pH was measured, and carcasses were classified as DC (pH = 6.69), or control (pH = 5.47). Then, strip loins from each animal were assigned to 2 aging methods (wet or dry). The 4 treatments included 2 dry aging (DRY and DRY-DC) and 2 wet-aging treatments (WET and WET-DC). Dry aging occurred in individual dry-aging chambers at 50% relative humidity and 2200 RPM fan speed. The chambers (86 cm Length × 48 cm Width × 35 cm Height) have built-in weighing scales that can continuously monitor weight loss (± 5 g). Wet and dry-aged loins were aged in the same cooler for 45 d at 1°C.After aging, loins were fabricated into steaks and evaluated for trim loss, yield, tenderness (WBSF), color, discoloration, lipid oxidation, and sensory analysis (flavor) via triangle test (n = 32). Steaks assigned for color and lipid oxidation were placed under retail display (RD) at 2°C for 7 d. Rate of moisture loss and color data were analyzed as a split plot design with repeated measures. The TBARS data were analyzed as a split-plot design. All the other data were analyzed as a completely randomized design. Chamber (loin) was considered the experimental unit. Data were analyzed using the PROC GLIMMIX procedure of SAS with α = 0.05.ResultsWet-aged treatments had lower moisture loss, trim loss and higher yield than dry-aged treatments (P < 0.05). However, no differences in rate of moisture loss (P = 0.51), total moisture loss (P = 0.96), trim loss (P = 0.69), or yield (P = 0.75) between DRY-DC and DRY were found. There were no differences among treatments for WBSF (P = 0.67). In general, DRY-DC and WET-DC steaks had the lowest lightness (L*) values, redness (a*) values (Fig. 3a), and yellowness (b*) values over the first 5 d of RD (P < 0.05). Discoloration scores for DC steaks remained low throughout the RD period (Fig. 3b). DRY steaks had greater TBARS values than any other treatment at 0 d RD. At 4 and 7 d of RD, DRY-DC and WET-DC steaks had the lowest TBARS values, DRY steaks had the highest, while WET was intermediate (P < 0.001). Results from the triangle test indicated a detectable difference between DRY-DC versus DRY (P = 0.01), DRY-DC versus WET-DC (P = 0.01), DRY-DC versus WET (P = 0.01), and WET-DC versus WET (P < 0.01). Panelists frequently made unsolicited comments which suggested inferior eating satisfaction associated with DC flavor (wet or dry), although they were not asked questions regarding preference.ConclusionUltimate pH did not affect the rate and total moisture loss in dry aged beef. Results suggest that neither yield nor flavor were positively affected by dry aging of DC beef.Figure 3.a) Effect of ultimate pH (Dark cutters [DC] vs. Normal) and aging method (Wet vs. Dry) on objective redness (a*) values of strip loins steaks aged for 45 d through 7 d of retail display. b) Effect of ultimate pH (Dark cutters [DC] vs. Normal) and aging method (Wet vs. Dry) on discoloration (%) of strip loins steaks aged for 45 d through 7 d of retail display. a-c Means within a day with different superscripts are different (P < 0.005).

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EFFECT OF PRE-FREEZING HAMS ON QUALITY ATTRIBUTES OF DRY-CURED PRODUCT

Journal of Milk and Food Technology ◽

10.4315/0022-2747-35.2.98 ◽

1972 ◽

Vol 35 (2) ◽

pp. 98-101 ◽

Cited By ~ 9

Author(s):

P. P. Graham ◽

T. N. Blumer

Keyword(s):

Weight Loss ◽

Relative Humidity ◽

Environmental Conditions ◽

Water Loss ◽

Moisture Loss ◽

Internal Tissue ◽

Surface Ph ◽

Aging Period ◽

Acceptable Quality ◽

Fresh State

Hams were frozen, stored, and thawed before dry-curing to study the profiles of quality as related to environmental conditions. Quality appraisals and sampling were done after thawing, after curing, and after 30 days aging in an atmosphere where temperature and relative humidity were controlled at about 34.5 C and 62.5%, respectively. The pH, water, NaCl, and fat contents were determined. Surface pH of hams increased from the thawed fresh state to the unstored cured state, but decreased generally after the aging period (stored cured ham). The pH was higher on the surface than that of corresponding internal areas. The pH of the internal tissue was lower for thawed product than cured or aged product. The average percent water decreased during curing and aging periods. Water loss after curing and after aging in the prefrozen hams was greater than that reported for unfrozen hams. The quantity of water, NaCl, and fat varied among the several muscle areas and reasons for variation are discussed. All hams were of acceptable quality at each appraisal period. Decreasing moisture levels of hams were reflected by decreases in conformation scores throughout the processing periods. Increased firmness was accompanied by weight loss, moisture loss, and increased NaCl percentage.

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The Duke Employee Weight Loss Program: Report of a Duke Diet and Fitness Center Pilot Study

International Journal of Occupational Safety and Health ◽

10.3126/ijosh.v4i2.10753 ◽

2016 ◽

Vol 4 (2) ◽

pp. 44-50

Author(s):

Leonor Corsino ◽

A. Garrett Hazelton ◽

Howard Eisenson ◽

Crystal Tyson ◽

Laura P. Svetkey ◽

...

Keyword(s):

Body Mass Index ◽

Weight Loss ◽

Pilot Study ◽

Body Mass ◽

Body Fat ◽

Repeated Measures ◽

Occupational Safety ◽

Post Intervention ◽

Baseline Weight ◽

The Impact

Background: Obesity is increasingly prevalent in the industrialized world. Obese workers have two times the number of workers’ compensation claims as those of non-obese workers. Worksite interventions may be especially effective because employees spend a large part of their day in the work environment, and both employee and employer have incentives to improve the employees’ health.Objective: To assess the impact of a 4 week employee intervention in participant’s weight, body fat and blood pressure.Methods: This was a pilot study. We assessed feasibility and impact compared to baseline at 4 weeks, 6 months, and 12 months post-program. The primary outcomes were weight and body mass index. Secondary outcomes included percent body fat and blood pressure. Results: Forty participants consented to be part of the study. Baseline weight was 97.8 kg [SD ± 17.05]. Twelve months post-intervention weight loss averaged 2.7 kg [SD ± 6.35]. One-way repeated measures ANOVA showed a significant effect of participation on weight, body mass index, and percent body fat.Conclusion: Significant improvements in the primary outcomes were observed in participants completing our worksite pilot study, indicating that a worksite weight loss intervention is potentially effective.International Journal of Occupational Safety and Health, Vol 4 No 2 (2014) 44– 50

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P079 Effect of sleepwear fibre type on menopausal sleep quality – Study protocol and preliminary data

SLEEP Advances ◽

10.1093/sleepadvances/zpab014.123 ◽

2021 ◽

Vol 2 (Supplement_1) ◽

pp. A46-A47

Author(s):

X Li ◽

M Halaki ◽

T Mahar ◽

S Ropert ◽

A Ireland ◽

...

Keyword(s):

Relative Humidity ◽

Sleep Quality ◽

Repeated Measures ◽

Sleep Disturbances ◽

Moisture Absorption ◽

Severity Index ◽

Vasomotor Symptoms ◽

Hot Flush ◽

Menopausal Women ◽

The Impact

Abstract Introduction Vasomotor symptoms and sleep disturbances are common in menopausal women. Different fabric types affect thermal comfort through moisture absorption and thermal insulation. This study examined the impact of cotton and wool sleepwear on menopausal women’s sleep quality. Methods This is a randomized, crossover, repeated-measures and triple-blinded trial comparing the sleep quality and vasomotor symptoms of healthy menopausal women between cotton and wool sleepwear at 30°C, 50% relative humidity. Participants undergo 6 laboratory visits. After a screening visit and a familiarization night, participants are randomized to 4 nights (2 nights in cotton and 2 nights in wool sleepwear) during which polysomnography and actigraphy recordings are taken including objective hot flush events, room temperature and relative humidity measurements, as well as subjective questionnaires on clothing comfort, mood and vasomotor symptoms. Results Eleven participants (age 51.2±4.7 years, BMI 26.8±2.9 kg.m-2, Insomnia Severity Index 11.1±5.5) completed all six visits so far. Reasons for exclusion: 3 didn’t have vasomotor symptoms; 1 on HRT, 5 had severe sleep disturbances, 3 on medications, 4 had diabetes, 1 asthma, and 1 had BMI>30. All sleep-related outcomes are pending analysis (blinding). Discussion Recruitment is a major study challenge. Many participants found it hard to arrange a time to attend overnight studies due to family/work commitments. The COVID-19 pandemic changed people’s attitude as some were hesitant to attend the laboratory. Menopause transition status is an important time during women’s lifespan. Effective management, e.g., through appropriate sleepwear, would be helpful to improve menopausal women’s symptom and quality of life.

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The Impact of Prescribed Exercise and Short-Term Caloric Restriction on Moderate-to-Vigorous Physical Activity (P08-011-19)

Current Developments in Nutrition ◽

10.1093/cdn/nzz044.p08-011-19 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

Author(s):

Alexandra Martin ◽

Birgit Wallmann-Sperlich ◽

Billy Sperlich ◽

Karsten Koehler

Keyword(s):

Physical Activity ◽

Weight Loss ◽

Energy Balance ◽

Caloric Restriction ◽

Repeated Measures ◽

Vigorous Physical Activity ◽

Energy Deficit ◽

Short Term ◽

Food And Agriculture ◽

The Impact

Abstract Objectives Weight loss, especially when achieved by caloric restriction (CR), reduces total daily energy expenditure (EE), which can attenuate further weight loss. Although exercise is a common countermeasure to the decline in EE, it is unknown whether prescribed exercise leads to compensatory changes in moderate-to-vigorous physical activities (MVPA) during non-exercise periods in the context of CR. The present study sought to quantify changes in MVPA in response to an energetically-matched energy deficit induced by CR alone or combined with exercise. We hypothesized that MVPA outside of prescribed exercise would be greater during non-exercise conditions, regardless of energy balance. Methods In a repeated-measures crossover design, active men (n = 6, 25 ± 1.0 y) underwent four 4-day conditions: CR with exercise (CR + X), CR without exercise (CR–X), energy-balanced control (CON) with exercise (CON + X) and without exercise (CON–X). Dietary intake was manipulated such that energy availability (EA) was 15 kcal·kg FFM−1·day−1 (CR) or 40 kcal·kg FFM−1·day−1 (CON). Prescribed exercise EE was 15 kcal·kg FFM−1·day−1. Physical activity was assessed using the SenseWear Pro3 armband (Bodymedia, Pittsburgh, USA) to quantify time spent in MVPA and light activities (sleep, lying down without sleep, and non-lying light activities) as % of total wear time. Results EA did not differ between CR (P = 0.87) nor CON (P = 0.42). As expected, weight loss was significant (P < 0.001) in CR + EX (–1.8 ± 0.4 kg) and CR-EX (–2.4 ± 0.3 kg). After deducting prescribed exercise, there was a significant effect of exercise on time spent in MVPA (P = 0.02), in that MVPA was lower during CON-EX vs. CON + EX (11.4 ± 2.0% vs. 17.9 ± 2.1%, P = 0.03) and trended lower during CR-EX vs. CR + EX (13.6 ± 1.5% vs. 15.5 ± 1.6%, P = 0.08). In exercise conditions, MVPA was lower during CR + EX when compared to CON + EX (P = 0.03). Conclusions Independent of energy balance, engaging in short-term exercise led to more, not less, time spent in non-exercise MVPA. These findings indicate the prevention of reductions in non-exercise activity as an additional benefit of incorporating exercise into weight loss interventions. Funding Sources The study was supported in part by the USDA National Institute of Food and Agriculture and institutional funding from the University of Nebraska-Lincoln.

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Men’s Weight Loss Outcomes, Behaviors, and Perceptions in a Self-Directed Commercial Mobile Program: Retrospective Analysis

Health Education & Behavior ◽

10.1177/10901981211055467 ◽

2021 ◽

pp. 109019812110554

Author(s):

Heather Behr ◽

Annabell Suh Ho ◽

Qiuchen Yang ◽

Ellen Siobhan Mitchell ◽

Laura DeLuca ◽

...

Keyword(s):

Weight Loss ◽

Behavior Change ◽

Weight Management ◽

Repeated Measures ◽

Full Length ◽

Weight Loss Outcomes ◽

The Many ◽

Behavior Change Program ◽

The Impact ◽

Weight Management Programs

Background There is little understanding of men’s weight loss outcomes and behaviors in self-directed contexts, such as digital commercial mobile weight management programs. This is an especially pressing question given that men often express disinterest in weight management programs and it is unknown how that manifests in self-directed environments. Aims. Two studies fill this gap by retrospectively observing how men lose weight and engage in weight loss behaviors (Study 1) and their perceptions of improvements and gained knowledge (Study 2) when participating in the full length of a commercial mobile behavior change program called Noom. Method In Study 1, repeated-measures linear mixed modeling was used to examine whether weight loss was statistically significant from baseline to 16 weeks and how engagement behaviors predicted weight in a sample of 7,495 male Noom users. In Study 2, 971 male Noom users completed an exploratory survey on the impact of the behavior change education in the program. Results In Study 1, men who remained in the full length of the program lost statistically significant weight from baseline to 16 weeks. 63% achieved clinically meaningful (5% or more) weight loss. Engagement in weight loss behaviors on the program predicted the amount of weight lost. In Study 2, men reported learning most about practical application and psychological aspects relating to food and psychology. Discussion and Conclusion This is the first study to observe men’s weight loss outcomes, behaviors, and perceptions of what they learned in a self-directed behavior change program. Our findings have important implications for more effective health promotion for the many men who choose to self-direct their weight loss.

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Anti-Gravity Simulated Weight Reduction: A Pilot Study to Assess the Impact Upon Pain for Foot and Ankle Arthritis

Foot & Ankle Orthopaedics ◽

10.1177/2473011419s00313 ◽

2019 ◽

Vol 4 (4) ◽

pp. 2473011419S0031

Author(s):

William Morley ◽

Edward Dawe ◽

Robert Boyd ◽

James Creasey ◽

John Grice ◽

...

Keyword(s):

Weight Loss ◽

Weight Reduction ◽

Repeated Measures ◽

Obese Patients ◽

Foot And Ankle ◽

Ankle Arthritis ◽

Pain Scores ◽

The Uk ◽

A Prospective Study ◽

The Impact

Category: Ankle, Ankle Arthritis, Hindfoot, Midfoot/Forefoot Introduction/Purpose: Osteoarthritis in the foot and ankle affects approximately 30,000 patients annually in the UK. Evidence has shown that excess weight exacerbates foot pain, with significant increases in joint forces. However, despite the current UK trend for Clinical Commissioning Groups to ration surgery for obese patients, studies have not yet determined the effect of weight loss in obese patients with foot and ankle arthritis. Methods: Following ethical approval, a prospective study of 19 obese patients (mean BMI 39.2, range 31.2 – 50.3) with foot and ankle arthritis was undertaken with funding from BOFAS. Under physiotherapist supervision, patients walked for one minute on an anti-gravity treadmill, which allowed simulated weight reduction. Following baseline assessment, reduced BMI was simulated, starting at 20, rising in increments of 5, until each patient’s usual BMI was reached. Pain was assessed using a Visual Analogue Scale (VAS). Repeated measures ANOVA was used to assess for significant changes in pain, comparing baseline with each simulated BMI category (significance set at p<0.05). Results: Simulated weight loss to BMI 25 caused a significant reduction in pain (p<0.05, power 0.91). Mean VAS pain scores improved by 46% (22.8 points, p=0.002) and 32% (15.9 points, p=0.04) for BMI categories 20 and 25 respectively, compared with baseline. Pain scores were not significantly different comparing between BMI categories of 25 and 20. Conclusion: Simulated weight loss to normal BMI significantly decreased pain in obese patients with foot and ankle arthritis. The use of the anti-gravity treadmill to demonstrate the feeling of normal BMI has also provided motivation to several patients to lose weight. The current study could be used to power future studies to investigate the effects of weight loss in foot and ankle patients.

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