Investigation of the growth of Listeria in plant-based beverages

The objective of the present study was to evaluate whether the content of sugar, protein, fat, or fibre in commercially available and specially formulated plant-based beverages (oat, soya and pea) influences the growth rates of Listeria. Beverages were inoculated with a strain cocktail of Listeria (approximately 1 × 103 CFU/mL), and the data demonstrated that Listeria could proliferate in all tested beverages. Moreover, varying concentrations of naturally occurring or added sugar (0-3.3%), protein (3.3-5%), fat (1.1-3.5%) and added fibre (0-1.5%) did not have a statistically significant (p > 0.05) impact on the growth rates of Listeria in the tested plant-based beverages. These data suggest that the wide variety of commercial plant-based beverages serve as an ideal medium for the growth of Listeria irrespective of product composition. All the various products tested provided sufficient nutrients to support at least a 2.6-log increase of Listeria within 16 h at room temperature, with some beverages supporting a 3-log increase. Therefore, these data highlight the importance of careful storage and handling of these increasingly varied and popular products.

Using Dual-source Photon-counting Detector CT to Simultaneously Quantify Fat and Iron Content: A Phantom Study

RATIONALE AND OBJECTIVES

To evaluate the feasibility of using photon-counting detector computed tomography (PCD CT) to simultaneously quantify fat and iron content MATERIALS AND METHODS: Phantoms with pure fat, pure iron and fat-iron deposition were scanned by two tube voltages (120 and 140 kV) and two image quality (IQ) settings (80 and 145). Using an iron-specific three-material decomposition algorithm, virtual noniron (VNI) and virtual iron content (VIC) images were generated at quantum iterative reconstruction (QIR) strength levels 1-4.

RESULTS

Significant linear correlations were observed between known fat content (FC) and VNI for pure fat phantoms (r = 0.981-0.999, p < 0.001) and between known iron content (IC) and VIC for pure iron phantoms (r = 0.897-0.975, p < 0.001). In fat-iron phantoms, the measurement for fat content of 5-30% demonstrated good linearity between FC and VNI (r = 0.919-0.990, p < 0.001), and VNI were not affected by 75, 150, and 225 µmol/g iron overload (p = 0.174-0.519). The measurement for iron demonstrated a linear range of 75-225 µmol/g between IC and VIC (r = 0.961-0.994, p < 0.001) and VIC was not confounded by the coexisting 5%, 20%, and 30% fat deposition (p = 0.943-0.999). The Bland-Altman of fat and iron measurements were not significantly different at varying tube voltages and IQ settings (all p > 0.05). No significant difference in VNI and VIC at QIR 1-4.

CONCLUSION

PCD CT can accurately and simultaneously quantify fat and iron, including scan parameters with lower radiation dose.

Assessment of consumer demographics and food safety risks associated with ready-to-eat (RTE) homemade foods purchased online in the UAE

In the UAE, female entrepreneurs, termed "Tajrat", sell a variety of homemade food products over online social media (OSM) platforms. Some of these food products are prepared and sold outside regulatory channels, with serious public health consequences. The study aimed to identify consumer demographics associated with purchasing of RTE, homemade food sold over in OSM platforms in the UAE and to assess the food quality by evaluating microbiological quality and fat percentage in RTE foods. A representative survey of the population of the UAE (n = 1303) was conducted, covering consumer demographics, frequency of purchase, and respondents' perception towards safety and nutritional value. 66 % of respondents were Emiratis, fifty percent of whom purchased RTE foods online. Moreover, 61 % of participants purchased from "Tajrat" via OSM as opposed to other sources. Convenience (47 %) and taste (41 %) were the main drivers for purchasing RTE homemade foods. Although 76 % of respondents have at least one member of their family considered vulnerable, the safety levels, quality, and nutritional value of such products did not carry the same significance. Microbiological analysis of 35 food samples purchased online from "Tajrat" was conducted. Listeria spp. was isolated from 22 % of the samples, 43 % showed positive Staphylococcus aureus, and 31 % of the samples had coliform bacteria. Total Fat Content of RTE homemade food samples ranged between 2.6 and 30 g/100 g which is considered high and can cause serious health issues if consumed frequently. Recommendations from this study will help policy makers and regulators in the UAE to develop and implement education strategies targeting homemade food handlers.

Effect of fat concentration on protein digestibility of Chinese sausage

Chinese sausage is a popular traditional Chinese meat product, but its high-fat content makes consumers hesitant. The purpose of this study is to compare the nutritional differences of Chinese sausages with different fermentation times (0, 10, 20, 30 d) and fat content (the initial content was 11.59% and 20.14%) during digestion. The comparison of digestion degree, protein structure, and peptide composition between different sausages were studied through in vitro simulated digestion. Chinese sausages with high-fat content had higher α-helix, β-turn, and random coil, making them easier to digest. The fermentation process made this phenomenon more pronounced. The high-fat sausage fermented for 10 d showed the highest release of primary amino acids (about 9.5%), which was about 3.5% higher than the low-fat sausage under the same conditions. The results of peptidomics confirmed the relevant conclusions. After gastric digestion, the types of peptides in the digestive fluid of high-fat sausages were generally more than those in low-fat sausages, while after intestinal digestion, the opposite results were observed. The type of peptide reached its peak after fermentation for 20 d. These findings are of obvious significance for selecting the appropriate fermentation time and fat content of Chinese sausages.

The association between meat intake and the risk of coronary heart disease in Korean men using the Framingham risk score: A prospective cohort study

BACKGROUND AND AIMS

Research suggests that meat intake may increase the risk of coronary heart disease (CHD), but most studies take place in Western countries, where the types and amount of meat products consumed differ from those in Asian countries. We aimed to identify the association between meat intake and CHD risk in Korean male adults, using the Framingham risk score.

METHODS AND RESULTS

We used data from the Korean Genome and Epidemiology Study (KoGES) Health Examinees (HEXA) study, including 13,293 Korean male adults. We estimated the association of meat intake with ≥20% 10-year CHD risk using Cox proportional hazards regression models to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs). Subjects with the highest total meat intake had a 53% (model 4: HR 1.53, 95% CI 1.05-2.21) increased 10-year CHD risk compared to those with the lowest intake. Those with the highest red meat intake had a 55% (model 3: HR 1.55, 95% CI 1.16-2.06) increased 10-year CHD risk compared to those with the lowest intake. No association was observed between poultry or processed meat intake and 10-year CHD risk.

CONCLUSIONS

Consumption of total meat and red meat was associated with a higher risk of CHD in Korean male adults. Further studies are needed to provide criteria for the appropriate meat intake by meat type to reduce CHD risk.

Survival and predictive modeling of Listeria monocytogenes under simulated human gastric conditions in the presence of bovine milk products

Listeria monocytogenes is an opportunistic foodborne pathogen which has been implicated in many outbreaks of foodborne diseases. This study evaluated the effects of gastric acidity and gastric digestion time of adults, L. monocytogenes strain and food type on the survival of L. monocytogenes under simulated stomach conditions of adults in in vitro gastric models with dynamic pH changes occurring throughout the exposure. Individual strains as well as a cocktail of L. monocytogenes, inoculated at 8 log CFU/mL in filtered bovine milk products, 0 % milk, 2 % milk, 2 % chocolate milk and 3.25 % milk, were introduced to the gastric models for 2 h. The survival of L. monocytogenes depended on a combination of factors, including gastric acidity and gastric digestion time of adults, L. monocytogenes strain, food type and recovery method (P < 0.05). The survival rates of L. monocytogenes inoculated in 2 % milk after a 2-h exposure to simulated gastric fluids with pH values of 1.5, 2.0 and 3.0 were 0.003 to 0.040 %, 22.7 to 43.4 % and 16.6 to 27.2 %, respectively. Fluid milk containing a higher milk fat content (3.25 % vs 0 % milk) protected L. monocytogenes from being inactivated when they were exposed to the human stomach model with a gastric acidity of pH 2.0. Compared to 0 % and 3.25 % milk, L. monocytogenes survived the best in 2 % chocolate milk, which appears to be due to the presence of milk fat (2 %) and the additional nutrients that are present in chocolate milk. A predictive mathematical model was developed that captured the population of the strains of L. monocytogenes under the in vitro conditions. This study advances our understanding of the behaviour of L. monocytogenes under various human gastric conditions and provides key parameters that can affect the survival of L. monocytogenes in the stomachs of adults. The mathematical models developed in this study can be used as a supplementary tool to help predict the survival of L. monocytogenes under similar scenarios and for relevant risk-assessment studies.

A matter of body weight and sex type: Pig carcass chemical composition and pork quality

This study compares minced carcass chemical composition and meat quality of castrated (CM), immunocastrated (IM) and entire male (EM), and female (FE) pigs at 70, 100 and 120 kg target body weights (TBW) (n = 80; 20 per sex). Sex affected fat, protein, and moisture content of the minced carcasses. Carcass fatty acid (FA) composition was affected by sex, with higher saturated and monounsaturated FA content in CM than in FE, IM and EM, and higher polyunsaturated FA in CM than in EM, with FE and IM in between. Except for intramuscular fat, which was higher in CM than in FE and EM, no significant differences between sexes were found in meat quality. TBW affected carcass chemical composition and some meat quality traits. An interaction between sex and TBW was found with IM approaching EM or CM depending on TBW.

Olfactory discrimination of fat content in milks is facilitated by differences in volatile compound composition rather than odor intensity

The mechanisms underlying the ability of humans to olfactorily discriminate fat content in milks remain unknown. In this study, we found that fat contents (0.5, 1.5 and 3.5% fat) can be discriminated by olfaction in commercially available pasteurized milks (p < 0.05) but not in ultra-high temperature processed (UHT) milks. The composition of volatile compounds of pasteurized milks differed with fat content, whereas that of UHT milks differing in fat content was similar. Principal component analysis revealed that differences in volatile compound composition of pasteurized milks differing in fat content contribute to olfactory discrimination. In UHT milks, acetoin and 2-heptanone may mask odor differences leading to indistinguishable odors. No differences were observed regarding perceived odor intensity of pasteurized milks or UHT milks differing in fat content. We conclude that the olfactory discrimination of fat content in pasteurized milks is facilitated by differences in volatile compound composition rather than odor intensity.

The influence of edible coatings and natural antioxidants on fresh-cut potato quality, stability and oil uptake after deep fat frying

The effect of four edible hydrocolloid coatings (carboxymethyl cellulose, chitosan, pectin and gum arabic) on fresh-cut potato's colour, pH and moisture content during storage was studied. Possibility of coating enrichment with natural olive leaf extract and sodium ascorbate was also evaluated. Coatings scored as the best ones straight after coating or during storage for 7 days at 10 ± 1 °C, were used for deep fat frying of potato. Chitosan was shown to cause significant decrease in pH and browning of potato strips. Pectin was classified as good coating alone but in combination with olive leaf extract showed lower quality parameters of fresh-cut samples compared to control. Only carboxymethyl cellulose and gum arabic itself or enriched with olive leaf extract or sodium ascorbate were shown not to affect colour, pH and moisture during storage. Moreover, these coatings significantly reduced fat content in deep fat fried potato strips, without influence on L*, b*, whiteness index (WI), and ΔE.

Lipid-free tuna muscle samples are suitable for total mercury analysis

Tropical tunas are largely consumed worldwide, providing major nutritional benefits to humans, but also representing the main exposure to methylmercury, a potent neurotoxin that biomagnifies along food webs. The combination of ecological tracers (nitrogen and carbon stable isotopes, δ¹⁵N and δ¹³C) to mercury concentrations in tunas is scarce yet crucial to better characterize the influence of tuna foraging ecology on mercury exposure and bioaccumulation. Given the difficulties to get modern and historical tuna samples, analyses have to be done on available and unique samples. However, δ¹³C values are often analysed on lipid-free samples to avoid bias related to lipid content. While lipid extraction with non-polar solvents is known to have no effect on δ¹⁵N values, its impact on mercury concentrations is still unclear. We used white muscle tissues of three tropical tuna species to evaluate the efficiency and repeatability of different lipid extraction protocols commonly used in δ¹³C and δ¹⁵N analysis. Dichloromethane was more efficient than cyclohexane in extracting lipids in tuna muscle, while the automated method appeared more efficient but as repeatable as the manual method. Lipid extraction with dichloromethane had no effect on mercury concentrations. This may result from i) the affinity of methylmercury to proteins in tuna flesh, ii) the low lipid content in tropical tuna muscle samples, and iii) the non-polar nature of dichloromethane. Our study suggests that lipid-free samples, usually prepared for tropical tuna foraging ecology research, can be used equivalently to bulk samples to document in parallel mercury concentrations at a global scale.

Modeling Salmonella spp. inactivation in chicken meat subjected to isothermal and non-isothermal temperature profiles

Salmonella genus has foodborne pathogen species commonly involved in many outbreaks related to the consumption of chicken meat. Many studies have aimed to model bacterial inactivation as a function of the temperature. Due to the large heterogeneity of the results, a unified description of Salmonella spp. inactivation behavior is hard to establish. In the current study, by evaluating the root mean square errors, mean absolute deviation, and Akaike and Bayesian information criteria, the double Weibull model was considered the most accurate primary model to fit 61 datasets of Salmonella inactivation in chicken meat. Results can be interpreted as if the bacterial population is divided into two subpopulations consisting of one more resistant (2.3% of the total population) and one more sensitive to thermal stress (97.7% of the total population). The thermal sensitivity of the bacteria depends on the fat content of the chicken meat. From an adapted version of the Bigelow secondary model including both temperature and fat content, 90% of the Salmonella population can be inactivated after heating at 60 °C of chicken breast, thigh muscles, wings, and skin during approximately 2.5, 5.0, 9.5, and 57.4 min, respectively. The resulting model was applied to four different non-isothermal temperature profiles regarding Salmonella growth in chicken meat. Model performance for the non-isothermal profiles was evaluated by the acceptable prediction zone concept. Results showed that >80% of the predictions fell in the acceptable prediction zone when the temperature changes smoothly at temperature rates lower than 20 °C/min. Results obtained can be used in risk assessment models regarding contamination with Salmonella spp. in chicken parts with different fat contents.

Identification and investigation of mechanically separated meat (MSM) with an innovative ultrasonic method

An innovative analytical ultrasonic method for identification and investigation of Mechanically Separated Meat (MSM) samples is presented. To this end, the ultrasonic wave velocity (f=5MHz) in the investigated meat samples was measured. The measured ultrasonic velocity ranged from 1553.4 to 1589.9 m/s. The investigations were performed for: 1) minced hand deboned chicken fillets, 2) low pressure MSM from chicken carcasses, 3) low pressure MSM from chicken collarbones, 4) high pressure MSM from chicken carcasses and 5) high pressure MSM from chicken collarbones. Statistically significant (p<0.001) differences in the ultrasonic velocity were observed for each of investigated kinds of meat. High significant correlations were found between the ultrasonic velocity and the content of protein, fat, sodium and density of the investigated meat. The applicability of the developed ultrasonic method for identifying various kinds of meat and to determine the content of protein, fat, sodium and density was demonstrated.

Levels of heavy metals, total petroleum hydrocarbons, and microbial load in commercially valuable fish from the marine area of Tripoli, Lebanon

The present study aimed at evaluating the levels of microbiological contamination, total petroleum hydrocarbons (TPHs), and heavy metals (As, Cd, Hg, and Pb) in the edible tissues of commonly consumed fish (8 species) collected from the marine area of Tripoli, Northern Lebanon. Total coliform levels in all sampled fish, and Escherichia coli levels in Liza ramada only, exceeded the permissible limits set by FAO/WHO 2002. Staphylococcus aureus counts were within the recommended thresholds, while sulfate-reducing bacteria levels were the highest in fish of the genus Liza. Salmonella species and Listeria monocytogenes were not detected in all fish analyzed. Analysis of heavy metals levels showed that arsenic exhibited the highest levels among the assessed metals in all genera. Levels of As in Epinephelus, Diplodus, Oblada, and Liza were above the acceptable limits, while Cd levels were below the permissible limits set by the European Commission. Significant negative correlation was found between levels of As and Hg in muscle tissues and fish size (length). Levels of TPHs were the highest in fish of the genus Epinephelus. Significant difference in TPHs contamination was found within three fish genera, with Epinephelus being the most contaminated.

Genome-wide scan for common variants associated with intramuscular fat and moisture content in rainbow trout

BACKGROUND

Genetic improvement of fillet quality attributes is a priority of the aquaculture industry. Muscle composition impacts quality attributes such as flavor, appearance, texture, and juiciness. Fat and moisture make up about ~ 80% of the tissue weight. The genetic architecture underlying the fat and moisture content of the muscle is still to be fully explored in fish. A 50 K gene transcribed SNP chip was used for genotyping 789 fish with available phenotypic data for fat and moisture content. Genotyped fish were obtained from two consecutive generations produced in the National Center for Cool and Cold Water Aquaculture (NCCCWA) growth-selective breeding program. Estimates of SNP effects from weighted single-step GBLUP (WssGBLUP) were used to perform genome-wide association (GWA) analysis to identify quantitative trait loci (QTL) associated with the studied traits.

RESULTS

Using genomic sliding windows of 50 adjacent SNPs, 137 and 178 SNPs were identified as associated with fat and moisture content, respectively. Chromosomes 19 and 29 harbored the highest number of SNPs explaining at least 2% of the genetic variation in fat and moisture content. A total of 61 common SNPs on chromosomes 19 and 29 affected the aforementioned traits; this association suggests common mechanisms underlying intramuscular fat and moisture content. Additionally, based on single-marker GWA analyses, 8 and 24 SNPs were identified in association with fat and moisture content, respectively.

CONCLUSION

SNP-harboring genes were primarily involved in lipid metabolism, cytoskeleton remodeling, and protein turnover. This work provides putative SNP markers that could be prioritized and used for genomic selection in breeding programs.

Optimizing air-frying process conditions for the development of healthy fish snack using response surface methodology under correlated observations

Air frying technique was used for the preparation of fish cutlet-a popular fish snack with low fat content, better protein content and color. The process conditions viz: temperature varying from 160 to 200 °C and time varying from 5 to 15 min were optimized using response surface methodology. A factorial design with 9 runs satisfying rotatability conditions under correlated errors was formulated for the experiment. The parameters of first order response surface model with interaction were estimated by generalized least square method. The optimum temperature-time combination for air-frying condition was found to be 180 °C and 12 min, respectively for low fat content, better protein content and colour, comparable texture profile and sensory acceptability when compared to deep fried fish cutlet samples. Air-fried fish cutlets can be a healthier protein rich snack product as an alternative to deep fat fried fish cutlets.

Influence of benzene exposure, fat content, and their interactions on erythroid-related hematologic parameters in petrochemical workers: a cross-sectional study

BACKGROUND

Ubiquitously distributed benzene is a known hematotoxin. Increasing evidence has suggested that erythroid-related hematologic parameters may be sensitive to benzene exposure. Fat content, which is also closely associated with erythroid-related hematologic parameters, may affect the distribution and/or metabolism of benzene, and eventually benzene-induced toxicity.

METHODS

To explore the influence of benzene exposure, fat content, and their interactions on erythroid-related hematologic parameters, we recruited 1669 petrochemical workers and measured their urinary S-phenylmercapturic acid (SPMA) concentration and erythroid-related hematological parameters. Indices for fat content included body fat percentage (BF%), plasma total cholesterol (TC) and triglycerides (TG), and occurrence of fatty liver.

RESULTS

The dose-response curve revealed U-shaped nonlinear relationships of SPMA with hematocrit (HCT) and mean corpuscular hemoglobin concentration (MCHC) (P-overall < 0.001, and P-nonlinear < 0.015), as well as positive linear associations and r-shaped nonlinear relationships of continuous fat content indices with erythroid-related hematological parameters (P-overall ≤0.005). We also observed modification effects of fat content on the associations between benzene exposure and erythroid-related hematological parameters, with workers of lower or higher BF% and TG more sensitive to benzene-induced elevation of MCHC (P_interaction = 0.021) and benzene-induced decrease of HCT (P_interaction = 0.050), respectively. We also found that some erythroid-related hematologic parameters differed between subgroups of workers with different SPMA levels and fat content combination.

CONCLUSIONS

Our study suggested that benzene exposure, fat content, and their interactions may affect erythroid-related hematological parameters in petrochemical workers in a complex manner that are worthy of further investigation.

Lipid content influences division of labour in a clonal ant

The fat body, a major metabolic hub in insects, is involved in many functions, e.g. energy storage, nutrient sensing and immune response. In social insects, fat appears to play an additional role in division of labour between egg layers and workers, which specialize in non-reproductive tasks inside and outside their nest. For instance, reproductives are more resistant to starvation, and changes in fat content have been associated with the transition from inside to outside work or reproductive activities. However, most studies have been correlative and we still need to unravel the causal interrelationships between fat content and division of both reproductive and non-reproductive labour. Clonal ants, e.g. Platythyrea punctata, are ideal models for studying task partitioning without confounding variation in genotype and morphology. In this study, we examined the range of variation and flexibility of fat content throughout the lifespan of workers, the threshold of corpulence associated with foraging or reproduction and whether low fat content is a cause rather than a consequence of the transition to foraging. We found that lipid stores change with division of labour from corpulent to lean and, in reverted nurses, back to corpulent. In addition, our data show the presence of fat content thresholds that trigger the onset of foraging or egg-laying behaviour. Our study supports the view that mechanisms that regulate reproduction and foraging in solitary insects, in particular the nutritional status of individuals, have been co-opted to regulate division of labour in colonies of social insects.

Determination of selected heavy metal and analysis of proximate composition in some fish species from Ogun River, Southwestern Nigeria

The aquatic environment is continuously at the mercy of man's negative impact on it. This study was designed to determine the proximate composition and concentration of some heavy metals in four fish species - Oreochromis niloticus, Malapterurus electricus, Parachanna obscura, Chrysichthys nigrodigitatus in Ogun River, Nigeria. The fish species were collected from the Abeokuta axis of the river and analyzed for Manganese (Mn), Lead (Pb), Nickel (Ni), Cadmium (Cd) and Zinc (Zn) using atomic absorption spectrometry. The moisture, crude protein, ash and fat content of the four fish species were analyzed using standard methods. The results showed varying levels of accumulation of the metals among the four fish species. Pb was detected only in Oreochromis niloticus while Mn was detected only in Chrysichthys nigrodigitatus. Except in a few cases, Pb and Ni in muscles of Oreochromis niloticus and Parachanna obscura respectively, the liver and gills accumulated more metals than the muscles. The concentrations of the metals in all cases were beyond regulatory limits by International Standards. All the fishes had high moisture content between 75 and 80 %, while fat was the lowest nutrient (0.88–1.89 %) in all fish species. The differences in proximate values were not significant among fish species. The findings in this study may be a reflection of the pollution status of the Ogun River with heavy metals while also portraying the risk associated with the consumption of fish from the river.

Association Between SSR Molecular Markers and Chemical and Sensory Traits of Cacao Samples Using Multiple Regression Analysis

The sensory properties of cacao beans are linked to the chemical composition of the seeds, and both characteristics are the partial results of its allelic composition. Therefore, it is useful to search for molecular markers associated with these traits. We perform multiple regression analysis to associate previously generated data of alleles generated with 12 SSR (of cultivated cacao trees) with data obtained from chemical and sensory characterization (of beans) of plants grown in the southern region from Mexico. When the association was significant, the mathematical models for predictive purposes were proposed. All phenotypic traits evaluated showed equations with setting values R² > 0.5. All chemical characters tested have a significant association with at least two alleles (P < 0.05). In addition, the fat content was associated with six molecular markers (mTcCIR03₂₀₉, mTcCIR12₁₈₈, mTcCIR19₂₈₆, mTcCIR07₁₅₀, mTcCIR19₃₁₀). The most common allele was mTcCIR12₁₈₈, which was associated with the contents of eicosanoic acid, moisture, fat and total polyphenols content. The mTcCIR28₃₆₂ allele is associated with sensory characters bitterness, musty odor, and roasted odor. These alleles could be useful as molecular markers of chemical and sensory characteristics of cacao samples.

Quantification of fat content in lipid-rich myxoid liposarcomas with MRI: a single-center experience with survival analysis

OBJECTIVE

To determine the fat content of myxoid liposarcomas (MLS) on MRI and to identify any association between lipid content and survival.

MATERIALS AND METHODS

The fat percentage of MLS diagnosed between January 2006 and December 2016 at a single institution was assessed by two radiologists on preoperative MR images. A Cox proportional hazard model was used to determine any association between tumor fat percentage and survival time. Tumor fat percentage was the single predictor in the model. A significance level of 0.05 was used. The Kaplan-Meier estimator was also used to provide a nonparametric estimate of the survivor function within the entire sample and within two patient subgroups consists of lipid-rich and lipid-poor tumors. Lipid-rich tumors were defined as any tumors showing more than 20% of fat on MRI. A 20% cutoff was determined arbitrarily.

RESULTS

Of the 43 cases identified through retrospective review, 8 tumors demonstrated ≥10% fat on MRI, and 4 tumors demonstrated ≥20% fat (highest fat percentage, 38%). There was no significant survival difference between patients with high tumor fat, which was defined as ≥20% fat, compared with those with little to no tumor fat.

CONCLUSION

Myxoid liposarcomas may demonstrate a higher fat content on MRI than has previously been reported in the literature. Increased tumor fat percentage in lipid-rich tumors was not found to be associated with increased risk of death. Radiologists must be aware of the existence of MLS lesions with higher fat content.

Blood lipid profile and body composition in a pediatric population with different levels of physical activity

Background

Associations between physical activity and lipid/lipoprotein levels and body composition among pediatric populations are not completely consistent in the literature. Accordingly, the aim of this study was to analyze lipid and lipoprotein profiles and body composition among children and adolescents differentiated according to their level of physical activity.

Methods

The study sample consisted of 69 participants that ranged from 6 to 17 years of age. Objective measures of physical activity were obtained over 7 days with accelerometers. Total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides (TG) were measured from a fasting blood sample. High-risk values for these lipids/lipoproteins were determined using age- and sex-specific thresholds. Body composition estimates were obtained using a foot-to-foot bioelectrical impedance analysis.

Results

Almost half (47.8%) of the participants did not meet daily moderate-to-vigorous intensity physical activity (MVPA) recommendations. This group had lower free fat mass (by 5.51%), muscle mass content (by 5.17%), and a higher risk for abnormal HDL level (OR = 4.19) and excessive body fat content (OR = 3.05).

Conclusions

Participants who met daily recommended MVPA were found to have more favorable HDL and body fat levels compared to those who did not meet these recommendations.

The effect of aggression I: The increases of metabolic cost and mobilization of fat reserves in male striped hamsters

Aggression can benefit individuals by enhancing their dominance and thereby their ability to acquire and retain resources that increase survival or fitness. Engaging in aggressive behavior costs energy and how animals manage their energy budget to accommodate aggression remains unclear. We conducted three experiments to examine changes in physiological, behavioral and hormonal markers indicative of energy budget in male striped hamsters subject to resident-intruder aggression tests. Body temperature, metabolic rate and serum corticosterone levels significantly increased in resident hamsters immediately after the introduction of intruders. Energy intake did not change, but the metabolic rate of residents increased by 16.1% after 42-days of repeated encounters with intruders. Residents had significantly decreased body fat content and serum thyroxine (T₄) levels, and a considerably elevated tri-iodothyronine (T₃)/T₄ ratio compared to a control group that had no intruders. Attack latency considerably shortened, and the number of attack bouts and total duration of attacks, significantly increased in residents on day 42 compared to day 1 of experiments. These findings may suggest that the conversion of T₄ to T₃ is involved in defensive aggression behavior. The mobilization of fat reserves resulting in lean body mass is probably common response to the increased metabolic cost of aggression in small mammals. Aggressive behavior, which is important for the successful acquisition and defense of resources, may be of significance for adaptation and evolution of metabolic rate.

Visual evaluation of sliced Italian salami by image analysis

Visual inspection is an important part of quality control not only for manufacturers but also for retailers and consumers. The object of this investigation was to determine fat content in sliced salami by means of image analysis. The image analysis procedure is applied to digital images of sliced Italian salami produced in 16 different salami factories (A–P). The image analysis method described in this work is nondestructive and the necessary equipment is cheap. It extracts directly interpretable parameters of fat particle morphology (e.g., area, roundness) and number of fat particles from 15 digital images for each sample (A–P). The correlations between the fat features extracted from the images with the chemical fat content measured on the samples were also studied. Good relationships were found between the fat particle characteristics measured by image analysis procedure and the percentage of chemically extractable fat by correlation (R²=0.75) and principal component analysis.

Optimization of low-fat set-type yoghurt: effect of altered whey protein to casein ratio, fat content and microbial transglutaminase on rheological and sensorial properties

In the present study the amount of whey protein to casein ratio (W/C ratio) (0.22-0.7), fat content (FC) (0.5-1.5%) and microbial transglutaminase (mTGase) (0.0-1.0 U/g substrate protein) in the formulation of low fat set type yoghurt, prepared from reconstituted milk, were optimized by response surface method to achieve the best rheological properties and sensory characteristics. The selected parameters consisted of higher consistency coefficient, consistency, texture and mouth feeling and lower syneresis and pH. The optimum condition was found to be 0.97, 0.46 and 0.5% of the enzyme concentration, W/C ratio and FC respectively. Results showed that thermal denaturation increased up to 33% with increasing W/C ratio significantly. All samples showed non-Newtonian shear thinning behavior. Increasing in W/C ratio from 0.22 to 0.7 raised the consistency coefficient, yield stress and textural parameters such as hardness and consistency of yoghurt. Enzyme addition (together with starter culture addition) increased yoghurt viscosity and yield stress. In sensory evaluation W/C ratio affected the texture and mouth feeling of yoghurt samples and the influences of FC and mTGase were not significant. Yoghurt syneresis was highly affected by FC, W/C ratio and mTGase.

The effects of fungal infection and physiological condition on the locomotory behaviour of the ant Myrmica scabrinodis

Parasite infection often results in alterations in host behaviour. These changes vary greatly in their magnitude, from slight shifts in the time spent by the host performing a given activity to the appearance of novel behaviours. The effects of parasites can differ with the age and the physiological condition of the host. Rickia wasmannii is an ectoparasitic fungal symbiont in Myrmica ants that covers the whole body surface of the host and reduces its lifespan. The fungus is present in both young and old individuals, making it an optimal subject for the study of age-related parasitic effects. We tested the effect of fungal infection on the locomotory activity of the Myrmica scabrinodis ant in different age categories. The fat content of workers was measured as a proxy for their physiological status. Based on our findings, old workers bore more thalli and were leaner than young individuals, while they tended to move at higher speeds and with a lower degree of meandering. Young individuals covered smaller distances, at slower speeds and with a higher degree of meandering. Contrary to our expectations, the infection intensity of R. wasmannii affected neither the fat content nor the locomotory activity of ant workers. However, the two age classes seem to have different strategies with regards to the relationship between fat content and distance covered. Our results suggest that characteristics of locomotory activity differ between the age classes in many respects, and are also influenced by their physiological status, but parasitism by R. wasmannii does not seem to have a straightforward effect on any of the variables studied.

Novel method to determine the lipid content of breast milk

The fat content of breast milk is important to establish the levels of organic pollutants in human being. Traditional liquid-liquid method was reliability, but time-consuming. In this study, a rapid method that predicts the fat content of breast milk on the basis of an accurate measurement of density is developed. 17 milk powder solutions were prepared, and the densities of these solutions were calculated after measuring its volume and weight. Based on the fat content and density, three equation models, a linear functional equation and two equations obtained by polynomial regression between fat content and density, were established and demonstrated a positive relationship between the fat content and density. The three equations were used to predict the fat contents of fresh milk and breast milk based on weight, volume, and density, respectively. Results showed that the linear functional equation of density and fat content produced a satisfactory result when the density was between 0.9975 and 1.0566 g mL^-1, with the predicted fat content matching well with the results from the gravimetric method. A Bland-Altman analysis also showed that the linear functional equation and gravimetric method were consistent when it was applied to measure the fat content of breast milk (n = 124, P < 0.0001). The absolute percentage error of the analytical results was less than 42.1% which is much less than other method. The weight or the density of milk samples should be measured with an accuracy of more than 0.001 g or 0.001 g mL^-1, respectively, to obtain a low relative error.

The impact of spin coupling signal loss on fat content characterization in multi-echo acquisitions with different echo spacing

PURPOSE

This study aimed to assess the effect of echo spacing in transverse magnetization (T2) signal decay of gel and fat (oil) samples. Additionally, we assess the feasibility of using spin coupling as a determinant of fat content.

METHODS

Phantoms of known T2 values, as well as vegetable oil phantoms, were scanned at 1.5T scanner with a multi echo FSE sequence of variable echo spacing above and below the empirical threshold of 20ms for echo train signal modulation (6.7, 13.6, 26.8, and 40ms). T2 values were calculated from monoexponential fitting of the data. Relative signal loss between the four acquisitions of different echo spacing was calculated.

RESULTS

Agreement in the T2 values of water gel phantom was observed in all acquisitions as opposed to fat phantom (oil) samples. Relative differences in signal intensity between two successive sequences of different echo spacing on composite fat/water regions of interest was found to be linearly correlated to fat fraction of the ROI.

CONCLUSION

The sample specific degree of signal loss that was observed between different fat samples (vegetable oils) can be attributed to the composition of each sample in J coupled fat components. Hence, spin coupling may be used as a determinant of fat content.

Comparison of gravimetric, creamatocrit and esterified fatty acid methods for determination of total fat content in human milk

The gravimetric method is considered the gold standard for measuring the fat content of human milk. However, it is labor intensive and requires large volumes of human milk. Other methods, such as creamatocrit and esterified fatty acid assay (EFA), have also been used widely in fat analysis. However, these methods have not been compared concurrently with the gravimetric method. Comparison of the three methods was conducted with human milk of varying fat content. Correlations between these methods were high (r(2)=0.99). Statistical differences (P<0.001) were observed in the overall fat measurements and within each group (low, medium and high fat milk) using the three methods. Overall, stronger correlation with lower mean (4.73g/L) and percentage differences (5.16%) was observed with the creamatocrit than the EFA method when compared to the gravimetric method. Furthermore, the ease of operation and real-time analysis make the creamatocrit method preferable.

Effects of origin and season on the lipids and sensory quality of European whitefish (Coregonus lavaretus)

The effect of variation in origin and season on the lipids and sensory quality of European whitefish (Coregonus lavaretus) was studied. The proportion of docosahexaenoic acid (22:6n-3) of the total phospholipid fatty acids in fillets was considerably higher in spring compared with autumn. Farmed fish contained 3-4 times more lipids than wild fish. Combined, the fillets of farmed fish contained 2-3 times more eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid than the fillets of wild fish. Contents of vitamin D were high both in farmed and wild fish. Aroma of raw farmed whitefish was less algae-like than wild one. Raw farmed whitefish was harder, less springy, and lighter in flesh color than wild whitefish. Cooked, farmed fish had slightly stronger flavor than wild fish. There was no significant difference in pleasantness between whitefish of different origin in any of the evaluated characteristics. Both farmed and wild European whitefish caught in autumn and spring proved to have a high content of n-3 fatty acids and vitamin D, and hence they serve as a good source of nutritionally important lipids.

Fatty acid composition of Swedish bakery products, with emphasis on trans-fatty acids

Trans-fatty acids (TFA) have been associated with increased risk of coronary heart disease, by affecting blood lipids and inflammation factors. Current nutrition recommendations emphasise a limitation of dietary TFA intake. The aim of this study was to investigate fatty acid composition in sweet bakery products, with emphasis on TFA, on the Swedish market and compare fatty acid composition over time. Products were sampled in 2001, 2006 and 2007 and analysed for fatty acid composition by using GC. Mean TFA levels were 0.7% in 2007 and 5.9% in 2001 of total fatty acids. In 1995-97, mean TFA level was 14.3%. In 2007, 3 of 41 products had TFA levels above 2% of total fatty acids. TFA content had decreased in this product category, while the proportion of saturated (SFA) and polyunsaturated (PUFA) fatty acids had increased, mostly through increased levels of 16:0 and 18:2 n-6, respectively. The total fat content remained largely unchanged.

Effects of glucagon-like peptide-1 receptor agonists on non-alcoholic fatty liver disease and inflammation

Glucagon-like peptide1 (GLP-1) is secreted from Langerhans cells in response to oral nutrient intake. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are a new class of incretin-based anti-diabetic drugs. They function to stimulate insulin secretion while suppressing glucagon secretion. GLP-1-based therapies are now well established in the management of type 2 diabetes mellitus (T2DM), and recent literature has suggested potential applications of these drugs in the treatment of obesity and for protection against cardiovascular and neurological diseases. As we know, along with change in lifestyles, the prevalence of non-alcoholic fatty liver disease (NAFLD) in China is rising more than that of viral hepatitis and alcoholic fatty liver disease, and NAFLD has become the most common chronic liver disease in recent years. Recent studies further suggest that GLP-1RAs can reduce transaminase levels to improve NAFLD by improving blood lipid levels, cutting down the fat content to promote fat redistribution, directly decreasing fatty degeneration of the liver, reducing the degree of liver fibrosis and improving inflammation. This review shows the NAFLD-associated effects of GLP-1RAs in animal models and in patients with T2DM or obesity who are participants in clinical trials.

Physicochemical, morphological and rheological properties of canned bean pastes "negro Queretaro" variety (Phaseolus vulgaris L.)

Proximate, thermal, morphological and rheological properties of canned "negro Querétaro" bean pastes, as a function of fat content (0, 2 and 3 %) and temperature (60, 70 and 85 °C), were evaluated. Raw and precooked bean pastes were characterized by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Well-defined starch granules in the raw bean pastes were observed, whereas a gelatinized starch paste was observed for the canned bean pastes. The DSC analysis showed that the raw bean pastes had lower onset peak temperatures (79 °C, 79.1 °C) and gelatinization enthalpy (1.940 J/g), compared to that precooked bean pastes (70.4 °C, 75.7 °C and 1.314 J/g, respectively) thermal characteristics. Moreover, the dynamic rheological results showed a gel-like behavior for the canned bean pastes, where the storage modulus (G') was frequency independent and was higher than the loss modulus (G″). The non-linear rheological results exhibited a shear-thinning flow behavior, where the steady shear-viscosity was temperature and fat content dependent. For canned bean pastes, the shear-viscosity data followed a power law equation, where the power law index (n) decreased when the temperature and the fat content increased. The temperature effect on the shear-viscosity was described by an Arrhenius equation, where the activation energy (Ea) was in the range from 19.04 to 36.81 KJ/mol. This rheological behavior was caused by gelatinization of the starch during the cooking and sterilization processes, where starch-lipids and starch-proteins complex were formed.

Optimising aroma quality in curry sauce products using in vivo aroma release measurements

Reducing fat content in foods to meet consumers' preferences and to address the obesity issue is a key task for food manufacturers but simply reducing fat content affects aroma quality adversely. Measuring the aroma release from regular and low-fat samples during eating to rebalance the aroma release has proved successful in model systems. Here, the reformulation of the spice content in a low fat curry sauce is described. Volatile markers of the key spices (coriander, cumin and turmeric) were selected and used to measure aroma release in regular (10 g oil/100 g) and low (2.5 or 5 g oil/100 g) fat sauces. Regression models were used to adjust the ingredient formulation so that the aroma release profiles in vivo were the same for the regular and reduced oil curry sauces and sensory analysis showed no significant difference between these samples. Despite the complexity of spice aromas, rebalancing was successful.

Effect of fat content, casing type and smoking procedures on PAHs contents of Portuguese traditional dry fermented sausages

Portuguese dry fermented sausages are traditionally processed through direct drying/smoking, making them susceptible to polycyclic aromatic hydrocarbons (PAHs) contamination. The purpose of this study was to assess the effect of added fat (20% and 40%), casing type (hog and collagen) and smoking procedures (direct and indirect exposure) on the 16 EPA priority PAHs in dry fermented sausages manufactured according traditional processing. The total PAHs content (sum of 16 PAHs) found in whole product (casing included) varied between 150 and 870 μg kg(-1), with more than 99% of this content corresponding to harmless low molecular weight compounds. Concerning benzo(a)pyrene (BaP) and PAH4, the respective maximum contents (0.32 and 10.35 μg kg(-1), respectively) did not exceed the imposed limits regulated by the European Union. According to our results, casing type was the most influential factor. For hog samples, fat content and smoking regime alone did not influenced the total PAHs amount. However, significantly higher (p<0.05) contamination levels were detected in hog casing samples combining high fat content and direct smoking procedures. In opposition, irrespective of the fat content and smoking regime, safer products, with significantly lower (p<0.001) contamination levels, were obtained when collagen casing was used.

Comparison of different methods for total lipid quantification in meat and meat products

This study was aimed to evaluate the efficiency of six extraction methods for the quantification of total lipid content in meat and meat products: standard Soxhlet method (with and without previous acid hydrolysis), continuous Soxhlet method (with and without previous acid hydrolysis), and those methods based in the use of a mixture of chloroform and methanol, and described by Folch, Less, and Sloane (1957) and Bligh and Dyer (1959). Lipid content was determined in nine different meat products with different fat contents and physico-chemical features: cooked turkey breast, fresh pork loin, cooked ham, dry-cured ham, mortadella, beef burger, fresh sausage, dry-cured sausage and salami. The most effective methods for determining fat content in the studied meat products were the method described by Folch et al. (1957) and the Soxhlet with previous acid hydrolysis method. The Soxhlet method without previous acid hydrolysis adequately extracted lipids only in those meat products with very high fat content. The use of the method described by Bligh and Dyer (1959) gave rise to the lowest lipid contents in all the studied meat products.

Semi-claustral colony founding in the seed-harvester ant Pogonomyrmex californicus: a comparative analysis of colony founding strategies

The evolution of queens that rear their first brood solely using body reserves, i.e. fully claustral, is viewed as a major advance for higher ants because it eliminated the need for queens to leave the nest to forage. In an apparently unusual secondary modification, the seed-harvester ant Pogonomyrmex californicus displays obligate queen foraging, i.e. queens must forage to garner the resources necessary to survive and successfully rear their first brood. I examined the potential benefits of queen foraging by comparing ecological and physiological traits between P. californicus and several congeners in which the queen can rear brood using only body reserves. The primary advantage of foraging appears to lie in providing the queens of P. californicus with the energy to raise significantly more brood than possible by congeners that use only body reserves; the workers reared in the first brood were also heavier in mass than that predicted by their head width. Other correlates of queen foraging in P. californicus relative to tested congeners included a significantly lower total fat content for alate queens, a small queen body size, and a low queen to worker body mass ratio. Queens also forage in several other well-studied species of Pogonomyrmex, suggesting the possibility that queen foraging may be more common than previously thought in higher ants.

Size and fat content of gynes in relation to the mode of colony founding in ants (Hymenoptera; Formicidae)

In ants, there are two main processes of colony founding, the independent and the dependent modes. In the first case young queens start colony founding without the help of workers, whereas in the second case they are accompanied by workers. To determine the relation between the mode of colony founding and the physiology of queens, we collected mature gynes of 24 ant species. Mature gynes of species utilizing independent colony founding had a far higher relative fat content than gynes of species employing dependent colony founding. These fat reserves are stored during the period of maturation, i.e. between the time of emergence and mating, and serve as fuel during the time of colony founding to nurture the queen and the brood. Gynes of species founding independently but non claustrally were found to have a relative fat content intermediate between the values found for gynes founding independently and those founding dependently. This suggests that such gynes rely partially on their fat reserves and partially on the energy provided by prey they collect to nurture themselves and the first brood during the time of colony founding. Study of the fat content of mature gynes of all species has shown that it gives a good indication of the mode of colony founding.