Andy M
University of Arkansas, AGRI STAT LAB, Faculty Member
Formation of kidney stone affects approximately 1 in 11 people in the U.S., and it can develop into various adverse renal outcomes. Although American Urological Association guideline recommends hav...
Research Interests:
Research Interests:
Research Interests:
Two similar trials were conducted to evaluate the accuracy of the whole carcass rinse technique in combination with a most probable number (MPN) procedure for estimating the number of salmonellae on postchill broilers. Birds were reared... more
Two similar trials were conducted to evaluate the accuracy of the whole carcass rinse technique in combination with a most probable number (MPN) procedure for estimating the number of salmonellae on postchill broilers. Birds were reared in litter-floored pens and inoculated with Salmonella typhimurium (10(8) cfu/mL) on Days 2, 7, and 14. In each of the two trials six carcasses were consecutively rinsed four times. Each carcass was rinsed with 100 mL of sterile water in sterile plastic bags using an automated shaking device. Salmonellae were enumerated using a three-tube MPN procedure in selenite cystine broth. There were no statistical differences in log10 MPN salmonellae per milliliter of recovered rinse fluid due to trial or consecutive rinse. In several cases salmonellae were not recovered in the initial rinse but were recovered from consecutive rinses of the same carcass. A large amount of variation in MPN levels of salmonellae among individual carcasses occurred within each consecutive rinse. The data suggested that only a percentage of the total salmonellae present on a postchill carcass were recovered with each consecutive rinse, and the organisms were firmly attached prior to processing.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests: Mathematics, Poultry Science, Biology, Medicine, Animal Production, and 3 moreFood Sciences, Keel, and Broiler
Abstract Rice kernel hardness is an important characteristic to the rice industry because of the greater economic value of whole kernels over brokens. Rice hardness may be weakened by increased porosity, i.e., void spaces formed from... more
Abstract Rice kernel hardness is an important characteristic to the rice industry because of the greater economic value of whole kernels over brokens. Rice hardness may be weakened by increased porosity, i.e., void spaces formed from loose interaction between chemical components like starch, proteins and lipids. The objective of this study was to elucidate the impacts of rice proteins and lipids on porosity and hardness via heat treatment and solvent extraction. Brown rice kernels of similar thickness from four cultivars with varying protein and lipid contents were subjected to protein denaturation by heat treatment and/or lipid removal by hexane extraction and then characterized for protein solubility, residual lipids, porosity and breaking force. The results show that although porosity is generally negatively correlated with kernel hardness, porosity was primarily influenced by the quantity of proteins and lipids, whereas kernel hardness was primarily affected by their compositions. The continuity of the protein-starch matrix was the dominant factor that governed kernel hardness. This matrix is proposed to be strengthened by an increase in glutelin content and a decrease in non-polar lipids. This study demonstrates the importance of chemical composition on kernel hardness and elucidates the relationship between porosity and breaking force in rice kernels.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Our aim was to investigate the validity of osmolality from 24-h urine collection in examining the risk for calcium-oxalate (CaOx) kidney stone formation in patients with recurrent urolithiasis. Three hundred and twelve subjects... more
Our aim was to investigate the validity of osmolality from 24-h urine collection in examining the risk for calcium-oxalate (CaOx) kidney stone formation in patients with recurrent urolithiasis. Three hundred and twelve subjects (males/females: 184/128) from France with a history of recurrent kidney stones from confirmed or putative CaOx origin were retrospectively included in the study (46 ± 14 years, BMI: 25.3 ± 5.0 kg·m−2). Tiselius’ crystallization risk index (CRI) was calculated based on urinary calcium, oxalate, citrate, magnesium, and volume from 24-h samples. The diagnostic ability of 24-h urine osmolality to classify patients as high risk for kidney stone crystallization was examined through the receivers operating characteristics analysis. High risk for CaOx crystallization was defined as CRI > 1.61 and > 1.18, for males and females, respectively. The accuracy of urine osmolality to diagnose risk of CaOx stone formation (AUC, area under the curve) for females was 84.6%, with cut-off point of 501 mmol·kg−1 (sensitivity: 83.3%, specificity: 76.0%). Males had AUC of 85.8% with threshold of 577 mmo·kg−1 (sensitivity: 85.5%, specificity: 77.6%). A negative association was found between 24-h urine volume and osmolality (r = − 0.63, P < 0.001). Also, a positive association was found between 24-h urine osmolality and CRI (r = 0.65, P < 0.001), as well as urea excretion with CRI (r = 0.37, P < 0.001). In conclusion, urine osmolality > 501 and > 577 mmol·kg−1, in female and in male, respectively, was associated with a risk for CaOx kidney stone formation in patients with a history of recurrent urolithiasis. Thus, when CaOx origin is confirmed or suspected, 24-h urine osmolality provides a simple way to define individualized target of urine dilution to prevent urine crystallization and stone formation.
Research Interests:
Two similar trials were conducted in order to compare the variability in the number of salmonellae between the right and left sides of individual broiler carcasses with the variability among carcasses. In both trials, the variation... more
Two similar trials were conducted in order to compare the variability in the number of salmonellae between the right and left sides of individual broiler carcasses with the variability among carcasses. In both trials, the variation between carcass sides was equal and was significantly less than the variation among carcasses. For trials involving bactericidal treatment, the authors would suggest that the utilization of carcass halves (one side for control, the other for treatment) would allow for a more-sensitive evaluation of treatment effects.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Formation of kidney stone affects approximately 1 in 11 people in the U.S., and it can develop into various adverse renal outcomes. Although American Urological Association guideline recommends hav...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Two similar trials were conducted to evaluate the accuracy of the whole carcass rinse technique in combination with a most probable number (MPN) procedure for estimating the number of salmonellae on postchill broilers. Birds were reared... more
Two similar trials were conducted to evaluate the accuracy of the whole carcass rinse technique in combination with a most probable number (MPN) procedure for estimating the number of salmonellae on postchill broilers. Birds were reared in litter-floored pens and inoculated with Salmonella typhimurium (10(8) cfu/mL) on Days 2, 7, and 14. In each of the two trials six carcasses were consecutively rinsed four times. Each carcass was rinsed with 100 mL of sterile water in sterile plastic bags using an automated shaking device. Salmonellae were enumerated using a three-tube MPN procedure in selenite cystine broth. There were no statistical differences in log10 MPN salmonellae per milliliter of recovered rinse fluid due to trial or consecutive rinse. In several cases salmonellae were not recovered in the initial rinse but were recovered from consecutive rinses of the same carcass. A large amount of variation in MPN levels of salmonellae among individual carcasses occurred within each consecutive rinse. The data suggested that only a percentage of the total salmonellae present on a postchill carcass were recovered with each consecutive rinse, and the organisms were firmly attached prior to processing.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests: Mathematics, Poultry Science, Biology, Medicine, Animal Production, and 3 moreFood Sciences, Keel, and Broiler
Abstract Rice kernel hardness is an important characteristic to the rice industry because of the greater economic value of whole kernels over brokens. Rice hardness may be weakened by increased porosity, i.e., void spaces formed from... more
Abstract Rice kernel hardness is an important characteristic to the rice industry because of the greater economic value of whole kernels over brokens. Rice hardness may be weakened by increased porosity, i.e., void spaces formed from loose interaction between chemical components like starch, proteins and lipids. The objective of this study was to elucidate the impacts of rice proteins and lipids on porosity and hardness via heat treatment and solvent extraction. Brown rice kernels of similar thickness from four cultivars with varying protein and lipid contents were subjected to protein denaturation by heat treatment and/or lipid removal by hexane extraction and then characterized for protein solubility, residual lipids, porosity and breaking force. The results show that although porosity is generally negatively correlated with kernel hardness, porosity was primarily influenced by the quantity of proteins and lipids, whereas kernel hardness was primarily affected by their compositions. The continuity of the protein-starch matrix was the dominant factor that governed kernel hardness. This matrix is proposed to be strengthened by an increase in glutelin content and a decrease in non-polar lipids. This study demonstrates the importance of chemical composition on kernel hardness and elucidates the relationship between porosity and breaking force in rice kernels.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Our aim was to investigate the validity of osmolality from 24-h urine collection in examining the risk for calcium-oxalate (CaOx) kidney stone formation in patients with recurrent urolithiasis. Three hundred and twelve subjects... more
Our aim was to investigate the validity of osmolality from 24-h urine collection in examining the risk for calcium-oxalate (CaOx) kidney stone formation in patients with recurrent urolithiasis. Three hundred and twelve subjects (males/females: 184/128) from France with a history of recurrent kidney stones from confirmed or putative CaOx origin were retrospectively included in the study (46 ± 14 years, BMI: 25.3 ± 5.0 kg·m−2). Tiselius’ crystallization risk index (CRI) was calculated based on urinary calcium, oxalate, citrate, magnesium, and volume from 24-h samples. The diagnostic ability of 24-h urine osmolality to classify patients as high risk for kidney stone crystallization was examined through the receivers operating characteristics analysis. High risk for CaOx crystallization was defined as CRI > 1.61 and > 1.18, for males and females, respectively. The accuracy of urine osmolality to diagnose risk of CaOx stone formation (AUC, area under the curve) for females was 84.6%, with cut-off point of 501 mmol·kg−1 (sensitivity: 83.3%, specificity: 76.0%). Males had AUC of 85.8% with threshold of 577 mmo·kg−1 (sensitivity: 85.5%, specificity: 77.6%). A negative association was found between 24-h urine volume and osmolality (r = − 0.63, P < 0.001). Also, a positive association was found between 24-h urine osmolality and CRI (r = 0.65, P < 0.001), as well as urea excretion with CRI (r = 0.37, P < 0.001). In conclusion, urine osmolality > 501 and > 577 mmol·kg−1, in female and in male, respectively, was associated with a risk for CaOx kidney stone formation in patients with a history of recurrent urolithiasis. Thus, when CaOx origin is confirmed or suspected, 24-h urine osmolality provides a simple way to define individualized target of urine dilution to prevent urine crystallization and stone formation.
Research Interests:
Two similar trials were conducted in order to compare the variability in the number of salmonellae between the right and left sides of individual broiler carcasses with the variability among carcasses. In both trials, the variation... more
Two similar trials were conducted in order to compare the variability in the number of salmonellae between the right and left sides of individual broiler carcasses with the variability among carcasses. In both trials, the variation between carcass sides was equal and was significantly less than the variation among carcasses. For trials involving bactericidal treatment, the authors would suggest that the utilization of carcass halves (one side for control, the other for treatment) would allow for a more-sensitive evaluation of treatment effects.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Background and ObjectivesRice aging is an intrinsic phenomenon that leads to physicochemical changes in rice kernels. The goal of this study is to determine the physicochemical properties of rice dried using a 915 MHz microwave and then... more
Background and ObjectivesRice aging is an intrinsic phenomenon that leads to physicochemical changes in rice kernels. The goal of this study is to determine the physicochemical properties of rice dried using a 915 MHz microwave and then aged. Two rice cultivars, a medium grain cultivar Titan and long grain hybrid cultivar XL753, with a harvest moisture content of 20% ± 1% (wet basis) were used for the study. The rice samples were treated with two different drying methods, natural air drying as control and microwave heating at 915 MHz frequency followed by tempering and natural air cooling at 25°C and 56% relative humidity (RH). Microwave‐dried samples were treated at specific energies ranging from 360 to 630 kJ/kg of initial wet grain mass (kJ/kg‐grain). Head rice samples were stored for 6 months at 4°C and 25°C representing nonaged and aged samples, respectively. Physicochemical properties of the samples were determined.FindingsAged microwave‐dried rice had significantly higher setback viscosity, cooked rice hardness and gumminess, and significantly lower peak viscosity and solid loss than nonaged rice. The changes in the viscosity profiles of aged microwave‐dried rice were generally similar to the trends recorded for aged control rice. Furthermore, aging significantly increased the water uptake and kernel elongation ratio of microwave‐dried rice cultivar XL753 but had no significant impact on rice cultivar Titan. Statistical models indicate that the solid loss of microwave‐dried rice decreases by 0.083% while the final viscosity, kernel elongation ratio, and hardness increase by 30 cP, 0.014, and 41 g respectively, with every degree Celsius increase in aging temperature (between 4°C and 25°C), when all other variables are kept constant. Also, aged microwave‐dried rice that were treated at 360 and 525 kJ/kg‐grain were practically equivalent in terms of hardness and solid loss.ConclusionsNatural aging of microwave‐dried rice (dried at 915 MHz frequency) led to changes in some physicochemical properties which were generally similar to the aging patterns of the control rice. Microwave specific energy of 525 kJ/kg‐grain is recommended for rice drying because it produces rice with desirable drying and aging properties.Significance and NoveltyThis study provides processing recommendations that can be used to select microwave parameters for rice drying, which will achieve desirable rice properties.
Research Interests:
Research Interests:
Research Interests:
Background and ObjectivesRice aging is an intrinsic phenomenon that leads to physicochemical changes in rice kernels. The goal of this study is to determine the physicochemical properties of rice dried using a 915 MHz microwave and then... more
Background and ObjectivesRice aging is an intrinsic phenomenon that leads to physicochemical changes in rice kernels. The goal of this study is to determine the physicochemical properties of rice dried using a 915 MHz microwave and then aged. Two rice cultivars, a medium grain cultivar Titan and long grain hybrid cultivar XL753, with a harvest moisture content of 20% ± 1% (wet basis) were used for the study. The rice samples were treated with two different drying methods, natural air drying as control and microwave heating at 915 MHz frequency followed by tempering and natural air cooling at 25°C and 56% relative humidity (RH). Microwave‐dried samples were treated at specific energies ranging from 360 to 630 kJ/kg of initial wet grain mass (kJ/kg‐grain). Head rice samples were stored for 6 months at 4°C and 25°C representing nonaged and aged samples, respectively. Physicochemical properties of the samples were determined.FindingsAged microwave‐dried rice had significantly higher setback viscosity, cooked rice hardness and gumminess, and significantly lower peak viscosity and solid loss than nonaged rice. The changes in the viscosity profiles of aged microwave‐dried rice were generally similar to the trends recorded for aged control rice. Furthermore, aging significantly increased the water uptake and kernel elongation ratio of microwave‐dried rice cultivar XL753 but had no significant impact on rice cultivar Titan. Statistical models indicate that the solid loss of microwave‐dried rice decreases by 0.083% while the final viscosity, kernel elongation ratio, and hardness increase by 30 cP, 0.014, and 41 g respectively, with every degree Celsius increase in aging temperature (between 4°C and 25°C), when all other variables are kept constant. Also, aged microwave‐dried rice that were treated at 360 and 525 kJ/kg‐grain were practically equivalent in terms of hardness and solid loss.ConclusionsNatural aging of microwave‐dried rice (dried at 915 MHz frequency) led to changes in some physicochemical properties which were generally similar to the aging patterns of the control rice. Microwave specific energy of 525 kJ/kg‐grain is recommended for rice drying because it produces rice with desirable drying and aging properties.Significance and NoveltyThis study provides processing recommendations that can be used to select microwave parameters for rice drying, which will achieve desirable rice properties.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Rice consumers in West Africa (WA) have an acquired preference for imported rice. Enhancing consumption of local rice requires matching the grain quality attributes of the imported benchmarks in addition to increasing productivity of... more
Rice consumers in West Africa (WA) have an acquired preference for imported rice. Enhancing consumption of local rice requires matching the grain quality attributes of the imported benchmarks in addition to increasing productivity of local rice cultivars. Thus, there is a need to develop screening tools that will aid breeding programs select for high-yielding and stress-tolerant cultivars whose grain quality are at par with imported rice. Hence, this study evaluated various grain quality characteristics of 316 commercial milled rice samples from urban markets in three WA countries (Benin, Cameroon, and Ghana) and developed linear discriminant models (LDAs) to classify rice according to their origins and to predict the imported rice classification of local germplasm based on their grain quality attributes. More than half of the commercial rice samples that were collected originated from Thailand (60%); in contrast, only a small fraction was locally grown (2%). The commercial rice from different origins were distinguishable based on the quality attributes evaluated, contributing to the relatively high classification rates achieved by the fitted LDAs. These results indicate that multivariate models could be useful during varietal improvement as tools for screening for cultivars that can match the quality of imported rice.
Research Interests:
Research Interests:
The purpose of this investigation was to assess the validity and reliability of a seven-day water frequency questionnaire (TWI-FQ) to estimate daily total water intake (TWI) in comparison to a water turnover objective reference value via... more
The purpose of this investigation was to assess the validity and reliability of a seven-day water frequency questionnaire (TWI-FQ) to estimate daily total water intake (TWI) in comparison to a water turnover objective reference value via deuterium oxide (D2O). Data collection occurred over 3 weeks, with a wash-out period during week two. Healthy adults (n = 98; 52% female; 41 ± 14 y; BMI, 26.4 ± 5.5 kg·m−2) retrospectively self-reported consumption frequencies of 17 liquids and 35 foods with specified volumes/amounts for weeks one and three via TWI-FQ. Standard water content values were utilized to determine the volume of water consumed from each liquid and food for calculation of mean daily TWI for each week. Diet records were completed daily during week two to estimate metabolic water production. To assess validity of the TWI-FQ, participants consumed D2O at the start of each week and provided urine samples immediately before ingestion, the following day, and at the end of the wee...