Soymilk stability increase using polyphenols microcapsules.

Functional beverages have aroused a great interest to the food industry. Among the functional ingredients, there is a growing demand for antioxidant incorporation into foods, which implies a challenge to preserve their bioactivity. The health benefits provided by soymilk can be improved by the addition with microcapsules of polyphenols from peanut skin and this procedure is an alternative to protect these natural and bioactive compounds from environmental factors. The aim of this work was to determine the chemical, antioxidant, microbiological and sensory changes during storage of the product. Soymilk samples were prepared without any addition (C); with peanut skin extract (BEA); and with microcapsules with polyphenols (MCBEA) and stored at 4 °C for 30 days. Results showed that the addition of polyphenols (free or microencapsulated) improved the chemical, microbiological and sensory stability of soymilk. The BEA and MCBEA had lower values of hydroperoxides, hexanal, bacterial growth, oxidised flavour, and sweet taste than C. The BEA exhibited higher phenol content (819.72 mg gallic acid equivalents/L), antioxidant activity (64.66% DPPH inhibition) and colour intensity than MCBEA. The study suggested that polyphenol microencapsulation is a procedure that can protect these sensitive compounds and control their release into this food matrix.

Microencapsulation of phenolic compounds extracted from soybean seed coats by spray-drying.

This study aimed to characterize and microencapsulate soybean seed coats phenolic compounds by spray-drying, evaluating physicochemical properties and storage stability. Different extraction methodologies were used to obtain crude extract (SCE), ethyl acetate fraction, water fraction, and bound phenolic extract. Extraction yield, total phenolic and flavonoid contents, and antioxidant capacity were determined. HPLC-electrospray ionization source-MS/MS analysis was performed on SCE. Microencapsulation by spray-drying of SCE incorporating 10%, 20%, and 30% maltodextrin (MD) was carried out. Drying yield (DY), encapsulation efficiency (EE), moisture, morphology and particle size, dry, and aqueous storage stability were evaluated on the microcapsules. SCE had 7.79 g/100 g polyphenolic compounds (mainly isoflavones and phenolic acids) with antioxidant activity. Purification process by solvent partitioning allowed an increase of phenolic content and antioxidant activity. Microcapsules with 30% MD exhibited the highest DY, EE, and stability. Microencapsulated polyphenolic compounds from soybean seed coats can be used as functional ingredients in food products. PRACTICAL APPLICATION: Soybean seed coat is a usually discarded agro-industrial by-product, which presents antioxidant compounds of interest to human health. These compounds are prone to oxidation due to their chemical structure; therefore, microencapsulation is a viable and reproducible solution to overcome stability-related limitations. Microencapsulation of soybean seed coats polyphenols is an alternative which protects and extends the stability of phenolic compounds that could be potentially incorporated into food products as a natural additive with antioxidant properties.

Environmental metal exposures and kidney function of Guatemalan sugarcane workers.

BACKGROUND: Exposure to environmental metals can cause nephrotoxicity. There is an international epidemic of chronic kidney disease of unknown cause (CKDu). Whether metal exposures contribute to kidney dysfunction in populations at risk for CKDu remains unresolved. OBJECTIVE: Urinary metals (arsenic, cadmium, nickel, and uranium) were examined in 222 sugarcane cutters in Guatemala at three time points over 1 year. METHODS: We explored the relationships between metal concentrations and markers of kidney function using multivariable linear mixed-effect models. RESULTS: Arsenic, cadmium, and nickel were detected in the majority of the 340 urine samples and were generally within limits previously considered to be nonnephrotoxic. Nevertheless, higher urine cadmium was inversely associated with estimated glomerular filtration rate (eGFR) (ß: -4.23, 95% confidence interval [CI]: -6.92, -1.54) and positively associated with neutrophil gelatinase-associated lipocalin (NGAL) (ß: 2.92, 95% CI: 1.20, 4.64). Higher urine arsenic was also inversely associated with eGFR (ß: -4.36, 95% CI: -7.07, -1.64). SIGNIFICANCE: Our findings suggest that exposures to metals, including cadmium and arsenic, might contribute to kidney toxicity seen in workers at risk for CKDu. These findings are consistent with the potential for metal nephrotoxicity at lower than expected levels in the setting of manual work in a very hot environment.

Body Composition, Anemia, and Kidney Function among Guatemalan Sugarcane Workers.

Rates of anemia among agricultural workers, who are also at risk for kidney injury and chronic kidney disease of unknown cause (CKDu), are unknown. We evaluated body composition through the sum of three skinfolds among 203 male sugarcane cutters and assessed the relationship of variables related to nutrition, anemia (hemoglobin < 13 g/dL), and elevated hemoglobin A1c (HbA1c ≥ 5.7%) with estimated glomerular filtration rate (eGFR) using linear regression. Eleven percent of workers were at the level of essential body fat (2-5%). Anemia was present among 13% of workers, 70% of which were normochromic normocytic, a type of anemia suggesting potential underlying chronic disease. Anemia was more common among those with lower BMI and fat free mass. The prevalence of elevated HbA1c was 21%. A moderate negative correlation was found between hemoglobin and HbA1c (Pearson's r = -0.32, p <0.01) which suggests that HbA1c values should be interpreted with caution in populations that have high rates of anemia. Twelve percent of workers had reduced kidney function with an eGFR < 90 mL/min/1.73 m2. On average, the eGFR was 18 mL/min per 1.73 m2 lower [(95% CI:-24, -12), p <0.01)] for those with anemia than those without, and 8 mL/min per 1.73 m2 lower among those with elevated HbA1c [(95% CI: -13, -2), p < 0.01]. Results will inform future studies examining the role of anemia in the evaluation of CKDu and interventions to improve nutrition for workers in low-resource settings.

Cross-sectional study examining the accuracy of self-reported smoking status as compared to urinary cotinine levels among workers at risk for chronic kidney disease of unknown origin in Guatemala.

OBJECTIVES: There is a lack of information on cotinine levels in rural populations in low-income and middle-income countries like Guatemala. Therefore, there is a need to explore smoking status and biomarkers of tobacco use in epidemiological research in rural, low-income populations, in particular those at-risk for chronic kidney disease of unknown origin (CKDu). DESIGN: We evaluated self-reported smoking status against urinary cotinine levels, the gold standard biomarker of tobacco smoke exposure, among agricultural workers at four separate cross-sectional time points. SETTING: Guatemala. PARTICIPANTS: 283 sugarcane workers. PRIMARY OUTCOME MEASURES: Compared self-reported smoking status and urinary cotinine levels in two agricultural worker studies. RESULTS: Self-reported smoking prevalence was 12% among workers. According to cotinine levels (≥50 ng/mL), the smoking prevalence was 34%. Self-reported smoking status had 28% sensitivity and 96% specificity. Urinary cotinine levels show that smoking prevalence is underestimated in this worker population. CONCLUSIONS: According to our findings, smoking status should be objectively measured with biomarkers rather than self-reported in CKDu epidemiological research. Self-reported smoking status is likely an underestimate of the true smoking prevalence among agricultural workers. Research on the CKDu epidemic in Central America and other parts of the world might be underestimating tobacco exposure as a potential contributor to the development of CKDu.

Workplace Screening Identifies Clinically Significant and Potentially Reversible Kidney Injury in Heat-Exposed Sugarcane Workers.

An epidemic of chronic kidney disease of unknown origin (CKDu) has emerged in the past two decades in agricultural communities, characterized by progressive renal failure with a dearth of early clinical symptoms. The aim of this study is to improve understanding of the natural history of this disease and to evaluate the impact of an educational and behavioral intervention on the trajectories of renal decline among a cohort of Guatemalan sugarcane workers. We identified groups of workers based on their kidney function during a longitudinal parent study conducted among sugarcane workers during the 2016-2017 harvest season. At the study's first time point in February 2017, workers who developed abnormal kidney function (AKF) (estimated glomerular filtration rate, eGFR, <60 mL/min per 1.73 m2) were placed in the AKF group, workers with reduced kidney function (RKF) (eGFR 60-89) were placed in the RKF group, and workers who maintained normal kidney function (NKF) (eGFR ≥ 90) were placed in the NKF group. As part of the study, a health promotion, behavioral and educational intervention centered on water, electrolytes, rest, and shade (WERS) was provided to all study participants. We then prospectively analyzed renal function at the three study time points in February, March, and April. Additional data collected from previous harvests allowed for retrospective analysis and we compared the rate of change in eGFR over the previous five years (2012 to 2016) for each identified group. Mixed effects linear regression with random intercepts for the workers was used to investigate the difference in rates of change for the three groups and to assess the impact of the intervention study on rate of change of kidney function during the study compared to each group's prior trajectory, utilizing the retrospective data collected during the five years prior to the study intervention. Between 2012 and 2016, eGFR declined at a rate of 0.18 mL/min per 1.73 m2 per year for the NKF group (95% CI: -0.66, 0.29, p = 0.45), 2.02 per year for the RKF group (95% CI: 1.00, 3.03, p = 0.0001) and 7.52 per year for the AKF group (95% CI: 6.01, 9.04, p < 0.0001). All study groups stabilized or improved their trajectory of decline during the intervention. This study supports the need to institute WERS interventions and to include mid-harvest screening protocols and longitudinal tracking of kidney function among sugarcane workers at high risk of CKDu. Early detection of rapid kidney function decline combined with appropriate interventions hold promise for stopping or slowing progression of renal insufficiency among these workers.

Rheological Behavior, Antimicrobial and Quorum Sensig Inhibition Study of an Argentinean Oregano Essential Oil Nanoemulsion.

In this study, Argentinean oregano essential oil (OEO) nanoemulsions (NEs) were developed. Four NEs were prepared: a control (CNE), EONE1 (10.6 mg EO/g NE), EONE2 (106 mg EO/ g NE), and EONE3 (160 mg EO/g NE) and tested for antimicrobial activity against Staphylococcus aureus ATCC 13565, Listeria monocytogenes Scott A, Pseudomonas aeruginosa ATCC 14213, and Escherichia coli O157:H7 using a broth microdilution assay and quorum sensing inhibition in a model using Chromobacterium violaceum ATCC 12472, where the production of violacein was quantified. The chemical composition of the EO was determined by gas chromatography-mass spectrometry. The average particle size (nm) and polydispersity index were monitored over 14 days at two different storage temperatures (4 and 23°C). A rheological behavior study was carried out using a dynamic shear rheometer, and flow curves, as well as viscoelastic properties, were determined. E. coli and L. monocytogenes were the most sensitive microorganisms to EONE (MIC of 2 and 5 mg/ml for EOEN3). Sub-MICs for NE were found at lower concentrations than those for pure EO. A significant reduction in violet pigment intensity and colorless coloration (p < 0.05) were observed at different NE concentrations concerning the control sample. The flow behavior index (n) decreased, and the consistency index (k) increased when the EO concentration was increased. CNE, EONE1, and EONE2 showed liquid-like behavior (G' < G″) in the low-frequency region, whereas a solid-like behavior (G' > G″) was observed in the high-frequency region, presenting a viscoelastic behavior, appearing as a wormlike micellar solution. For EONE3, a strong increase in both moduli was observed with increasing OEO concentration. The G' was about one order of magnitude higher than the G″ over the whole frequency range, indicating the presence of a gel-like structure. The incorporation of EOs into an NE increased their stability, lowering the particle size, leading to a wormlike micelle with higher viscosity. Moreover, this NE had good antimicrobial activity and novel quorum-sensing inhibition activity. The results of this study indicated that Argentinean OEO NE could be used in a food system as a natural and stable antimicrobial agent.

Electrolyte Beverage Intake to Promote Hydration and Maintain Kidney Function in Guatemalan Sugarcane Workers Laboring in Hot Conditions.

OBJECTIVES: To evaluate impact of electrolyte supplementation on hydration status and health outcomes in Guatemalan agricultural workers performing heavy work under hot climatic conditions. METHODS: A 3-week pragmatic trial was conducted with a group of 50 workers during the 2017 to 2018 sugarcane harvest. Workers received an electrolyte hydration intervention during 2 of the 3 weeks. Blood and urine samples were collected each week. RESULTS: Increased electrolyte intake resulted in less muscle injury. Kidney function was maintained across the intervention period. Workers were adequately hydrated and average electrolyte levels remained in normal ranges. Mild indications of hyponatremia occurred at higher levels of fluid intake. CONCLUSIONS: This trial demonstrates the feasibility of maintaining workers' electrolyte levels under extremely hot and humid conditions while mitigating muscle injury. Electrolyte supplementation should be added to standard workplace water, rest, and shade interventions to protect workers.

Improving walnuts' preservation by using walnut phenolic extracts as natural antioxidants through a walnut protein-based edible coating.

Walnut kernels contain high amounts of polyunsaturated fatty acids that determine a limited shelf life on these nuts. The application of walnut phenolics as antioxidants through a walnut protein-based coating, obtained from walnut oil cake residue, can help to increase the shelf life of walnuts. The objective was to evaluate the preservative effect of walnut polyphenols included in a walnut-proteic edible coating on walnut kernels. Three treatments of walnuts coated with walnut flour were prepared: without the addition of antioxidants (control); with the addition of a walnut phenolic extract; and with the addition of butylated hydroxytoluene (BHT). On the last storage day, the sample with the addition of walnut phenolics presented a lower peroxide (3.64 meq 02 /kg oil) and anisidine value (1.11), conjugated diene (15.92), and hexanal content (19.67 × 106 e.c.) than the control sample (6.23, 1.81, 24.65, and 122.37 × 106 e.c., respectively). Also, on the last day, the control sample showed the highest deterioration of polyunsaturated fatty acids (from 74.83 to 71.08 g/100g), carotenoid (from 3.43 to 1.90 mg/kg), and γ-tocopherol content (from 349.66 to 298.42 mg/kg). In addition, this sample exhibited the highest oxidized (20.33) and the lowest walnut flavor intensity (64.67) on day 84. Regarding consumer acceptance, the phenolic-added sample displayed a greater flavor acceptance score. Walnut phenolics, implemented through a walnut protein-based coating, improve the preservation of walnuts. PRACTICAL APPLICATION: The combination of walnut-phenolic extracts and walnut-based edible coating applied on walnuts by food industries allows to prolong their shelf life, by preserving their nutritional, sensory, and quality properties. Considering the practical feasibility, the procedure used to prepare these products is simple and requires machineries already present in food industries. In addition, the utilization of this coating with walnut-phenolics exerts benefits like, the prevention of allergen cross-contamination in the chain of production, the utilization of an industry's residue, the replacement of synthetic antioxidants and, and the diminishment of the amount and thickness of plastic needed for walnuts' packaging.

Longitudinal trends in renal function among first time sugarcane harvesters in Guatemala.

INTRODUCTION: Chronic kidney disease of unknown origin (CKDu) is an epidemic concentrated in agricultural communities in Central and South America, including young, male sugarcane harvesters. The purpose of this analysis is to understand early changes in kidney function among a cohort of first-time sugarcane harvesters and to determine risk factors for kidney function decline. METHODS: Joint latent class mixed models were used to model sub-population kidney function trajectory over the course of 4 years (2012-2016). Probability weighted logistic regression was used to determine personal health, community, and individual behavior risk factors associated with sub-population assignment. Data analysis occurred in 2019. RESULTS: Of 181 new workers median age 19 years old (IQR: 4), 39 (22%) were identified as having non-stable kidney function with an annual age-adjusted decline of estimated glomerular filtration rate (eGFR) of -1.0 ml/min per 1.73 m2 (95% CI: -3.4, 1.3). Kidney function (OR: 0.96; 95% CI: 0.93, 0.98), mild hypertension (OR: 5.21; 95% CI: 2.14, 13.94), and having a local home of residence (OR: 7.12; 95% CI: 2.41, 26.02) prior to employment in sugarcane were associated with non-stable eGFR sub-population assignment. CONCLUSIONS: Mild hypertension may be an early indicator of the development of CKDu. A better understanding of preexisting risk factors is needed to determine why individuals are entering the workforce with reduced kidney function and elevated blood pressure and increased risk of renal function decline.

Noise exposures of sugar cane mill workers in Guatemala.

Objective: To describe personal noise exposure measurements obtained on Guatemala sugar cane mill workers as a function of job category.Design: This is a descriptive evaluation of existing data.Sample: The data set included 51 representative noise dosimetry surveys utilising NIOSH sampling protocol, completed on workers performing 21 jobs in a Guatemalan sugar cane mill. Results: Noise doses ranged from a low of 50.9% to an extreme of 25174%. The highest observed mean noise doses were for evaporator cleaners (15761%) and juice extractors (2047%). Ninety percent of noise dosimetry samples were between 50% to 1200% dose. Annual noise exposures are also reported after considering the 7-month seasonal work schedule.Conclusions: The majority of sugar cane mill workers were exposed to hazardous occupational noise exceeding the Guatemalan permissible exposure limit (GMLSW), which is consistent with U.S. NIOSH recommended exposure limit of 100% noise dose (85 dBA time-weighted average). Consequently, the majority of workers should be enrolled in a hearing conservation programme including engineering noise control in order to prevent long-term adverse effects on workers' hearing.

Evaluation of heat stress and cumulative incidence of acute kidney injury in sugarcane workers in Guatemala.

OBJECTIVE: Agricultural workers worldwide exposed to heat stress could be at the risk of kidney injury, which could lead to chronic kidney disease of an unknown origin (CKDu). Hydration has been promoted as a key measure to reduce kidney injury. In the presence of a hydration intervention, the incidence of acute kidney injury (AKI) was calculated in a sugarcane worker population in Guatemala and several risk factors were evaluated. METHODS: We measured kidney function at the beginning and end of the work shift at three time points in 517 sugarcane workers. We defined AKI as an increase in serum creatinine of 26.5 µmol/L or 50% or more from the pre-shift value. Associations between AKI and risk factors were examined, including interactions with hydration status. RESULTS: The prevalence of dehydration post-shift (> 1.020 specific gravity) was 11% in February, 9% in March, and 6% in April. Cumulative incidence of AKI was 53% in February, 54% in March, and 51% in April. AKI was associated with increasing post-shift specific gravity, a dehydration marker, (OR 1.24, 95% CI 1.02-1.52) and with lower electrolyte solution intake (OR 0.94, 95% CI 0.89-0.99). CONCLUSIONS: Dehydration and insufficient electrolyte consumption are risk factors for AKI. However even well-hydrated sugarcane workers routinely experience AKI. While hydration is important and protective, there is a need to understand other contributors to risk of AKI and identify prevention strategies with these workers.

Risk Factors and Mechanisms Underlying Cross-Shift Decline in Kidney Function in Guatemalan Sugarcane Workers.

OBJECTIVE: Identify early biomarkers and mechanisms of acute kidney injury in workers at risk of developing chronic kidney disease of unknown origin (CKDu). METHODS: We assessed cross-shift changes in kidney function and biomarkers of injury in 105 healthy sugarcane workers. We obtained pre-harvest clinical data as well as daily environmental, clinical, and productivity data for each worker. RESULTS: The average percent decline in cross-shift estimated glomerular filtration rate (eGFR) was 21.8% (standard deviation [SD] 13.6%). Increasing wet bulb globe temperature (WBGT), high uric acid, decreased urine pH, urinary leukocyte esterase, and serum hyperosmolality were risk factors for decline in kidney function. CONCLUSIONS: Sugarcane workers with normal kidney function experience recurrent subclinical kidney injury, associated with elevations in biomarkers of injury that suggest exposure to high temperatures and extreme physical demands.

The impact of heat and impaired kidney function on productivity of Guatemalan sugarcane workers.

BACKGROUND: Climate change has implications for human health and productivity. Models suggest that heat extremes affect worker health, reduce labor capacity, and commodity supply. Chronic health conditions are on the rise internationally. However there is a paucity of direct empirical evidence relating increasing temperatures to both agricultural worker health and productivity. METHODS AND FINDINGS: We evaluated the relationship between temperature exposure, kidney function, and two measures of productivity-tons of commodity produced and job attrition, of 4,095 Guatemalan sugarcane cutters over a 6-month harvest. We used distributed lag non-linear models to evaluate associations between wet bulb globe temperature (WBGT) and productivity of workers with normal or impaired kidney function. The cumulative effect of exposure to a max WBGT of 34°C was 1.16 tons (95% CI: -2.87, 0.54) less sugarcane cut over the next five days by workers with impaired kidney function, compared to exposure to 29°C. Impaired kidney function was associated with premature workforce attrition. Workers starting the harvest season with impaired kidney function were more than twice as likely to leave employment (HR: 2.92, 95% CI: 1.88, 4.32). CONCLUSIONS: Heat extremes may be associated with loss of agricultural worker productivity and employment, especially among those with impaired kidney function. Agricultural workers who develop health conditions, such as kidney disease, are particularly vulnerable in the face of climate change and increasing heat extremes. The resultant loss of employment and productivity has significant implications for global commodity supplies.

Characterization of Argentinian Endemic Aspergillus flavus Isolates and Their Potential Use as Biocontrol Agents for Mycotoxins in Maize.

Maize (Zea mays L.) is a highly valuable crop in Argentina, frequently contaminated with the mycotoxins produced by Aspergillus flavus. Biocontrol products formulated with atoxigenic (nontoxic) strains of this fungal species are well known as an effective method to reduce this contamination. In the present study, 83 A. flavus isolates from two maize regions of Argentina were characterized and evaluated for their ability to produce or lack of producing mycotoxins in order to select atoxigenic strains to be used as potential biocontrol agents (BCA). All of the isolates were tested for aflatoxin and cyclopiazonic acid (CPA) production in maize kernels and a liquid culture medium. Genetic diversity of the nonaflatoxigenic isolates was evaluated by analysis of vegetative compatibility groups (VCG) and confirmation of deletions in the aflatoxin biosynthesis cluster. Eight atoxigenic isolates were compared for their ability to reduce aflatoxin and CPA contamination in maize kernels in coinoculation tests. The A. flavus population was composed of 32% aflatoxin and CPA producers and 52% CPA producers, and 16% was determined as atoxigenic. All of the aflatoxin producer isolates also produced CPA. Aflatoxin and CPA production was significantly higher in maize kernels than in liquid medium. The 57 nonaflatoxigenic strains formed six VCG, with AM1 and AM5 being the dominant groups, with a frequency of 58 and 35%, respectively. In coinoculation experiments, all of the atoxigenic strains reduced aflatoxin from 54 to 83% and CPA from 60 to 97%. Members of group AM1 showed a greater aflatoxin reduction than members of AM5 (72 versus 66%) but no differences were detected in CPA production. Here, we described for the first time atoxigenic isolates of A. flavus that show promise to be used as BCA in maize crops in Argentina. This innovating biological control approach should be considered, developed further, and used by the maize industry to preserve the quality properties and food safety of maize kernels in Argentina.

Risk Factors for Declines in Kidney Function in Sugarcane Workers in Guatemala.

OBJECTIVES: To characterize kidney function of sugarcane workers in Guatemala over the 6-month harvest and identify risk factors associated with changes in kidney function. METHODS: Demographic and biological data were collected for 330 sugarcane cutters at the beginning and end of the harvest. Multivariable regression analyses were used to assess factors related to kidney function. RESULTS: A decline in kidney function across the harvest was observed in 36% of the participants. Risk factors associated with this decline included working at a particular plantation mill, local area workers compared with highland workers, and current smokers. CONCLUSION: Results showed both occupational and behavioral factors play significant roles in declines in kidney function. These results underline the need for a comprehensive approach to the epidemic as well as further investigation of risk factors to guide research and interventions.

Antioxidant Stability Study of Oregano Essential Oil Microcapsules Prepared by Spray-Drying.

Release kinetics of the volatile compounds of oregano EO microcapsules and the relation with the antioxidant activity were studied. Different wall material (WM) to core (C) ratios (1:1 and 2:1; WM:C), addition of colloidal silicon dioxide (CSD); and different storage conditions: 23 °C (room temperature; R) and 4 °C (fridge temperature; F) were evaluated for 90 d. Volatile compounds, total phenolic content (TPC), free radical scavenging activity (FRSA), and Trolox equivalent antioxidant capacity (TEAC) were measured. The formulas 2:1 (WM:C) (R and F) without CSD behaved differently from the rest, exhibited a higher antioxidant activity, and released less amount of volatile compounds after 90 d. These treatments grouped together in the cluster analysis, showing the highest TPC (81.54 mg gallic ac/g), FRSA (8.66%), and TEAC (12.35 µg Trolox/g). The addition of CSD facilitated the released of volatile compounds through storage time and promoted losses in the antioxidant activity. The temperature had a significant effect in most of the evaluated variables. However, this effect was more noticeable in F2 (1:1, CSD). PRACTICAL APPLICATION: Oregano essential oil has antioxidant, antimicrobial, and sensory preserving properties. However, it is susceptible to volatilization and is degraded by external factors. Its addition into food matrices is restricted due to low solubility and hydrophobicity. The antioxidant activity of oregano EO is preserved after the process of microencapsulation by spray-drying that extends its stability during storage. Oregano EO microcapsules are an alternative of delivery which protects and extends the shelf life of this essential oil, overcomes stability related limitations and preserves its desirable characteristics allowing these kind of microcapsules to be later incorporated into food products. These microcapsules could be used as a natural additive/flavouring with antioxidant properties.

Sensory Quality Preservation of Coated Walnuts.

The objective of this study was to evaluate the sensory stability of coated walnuts during storage. Four walnut samples were prepared: uncoated (NC), and samples coated with carboxymethyl cellulose (NCMC), methyl cellulose (NMC), or whey protein (NPS). The samples were stored at room temperature for 210 d and were periodically removed from storage to perform a sensory descriptive analysis. A consumer acceptance test was carried out on the fresh product (storage day 0) to evaluate flavor. All samples exhibited significant differences in their sensory attributes initially and after storage. Intensity ratings for oxidized and cardboard flavors increased during storage. NC showed the highest oxidized and cardboard intensity ratings (39 and 22, respectively) and NMC exhibited the lowest intensity ratings for these negative attributes (8 and 17, respectively) after 210 d of storage. Alternatively, the intensity ratings for sweetness and walnut flavors were decreased for all samples. NMC had the lowest decrease at the end of storage for these positive attributes (75.86 in walnut flavor and 12.09 in sweetness). The results of this study suggest a protective effect of the use of an edible coating to preserve sensory attributes during storage, especially for samples coated with MC. The results of the acceptance test showed that addition of the coating negatively affected the flavor acceptance for NMC and NCMC coated walnuts. Edible coatings help to preserve sensory attributes in walnuts, improving their shelf-life, however, these coatings may affect consumer acceptance in some cases.

Chemical and Sensory Quality Preservation in Coated Almonds with the Addition of Antioxidants.

Almonds provide many benefits such as preventing heart disease due to their high content of oleic fatty acid-rich oil and other important nutrients. However, they are susceptible to oxidation reactions causing rancidity during storage. The objective of this work was to evaluate the chemical and sensory quality preservation of almonds coated with carboxymethyl cellulose and with the addition of natural and synthetic antioxidants during storage. Four samples were prepared: almonds without coating (C), almonds coated with carboxymethyl cellulose (CMC), almonds coated with CMC supplemented with peanut skins extract (E), and almonds coated with CMC and supplemented with butylhydroxytoluene (BHT). Proximate composition and fatty acid profile were determined on raw almonds. Almond samples (C, CMC, E and BHT) were stored at 40 °C for 126 d. Lipid oxidation indicators: peroxide value (PV), conjugated dienes (CD), volatile compounds (hexanal and nonanal), and sensory attributes were determined for the stored samples. Samples showed small but significant increases in PV, CD, hexanal and nonanal contents, and intensity ratings of negative sensory attributes (oxidized and cardboard). C had the highest tendency to deterioration during storage. At the end of storage (126 d), C had the highest PV (3.90 meqO2 /kg), and BHT had the lowest PV (2.00 meqO2 /kg). CMC and E samples had similar intermediate PV values (2.69 and 2.57 meqO2 /kg, respectively). CMC coating and the addition of natural (peanut skin extract) and synthetic (BHT) antioxidants provide protection to the roasted almond product.

Antioxidant effects of the monoterpenes carvacrol, thymol and sabinene hydrate on chemical and sensory stability of roasted sunflower seeds.

BACKGROUND: Oxidation products and rancid flavors decrease the sensory quality of food products, making them unacceptable to consumers. Synthetic antioxidants are used in many foods to prevent rancidity, though their safety is questioned. Monoterpenes are obtained from essential oils and many of them have shown antioxidant activity. The objective of this study was to evaluate the stability of sensory and chemical parameters in roasted sunflower seeds supplemented with carvacrol, thymol and sabinene hydrate monoterpenes. RESULTS: Five samples were prepared: control roasted sunflower seeds (RS-C) and sunflower seeds treated with carvacrol (RS-Car), sabinene hydrate (RS-S), thymol (RS-T) and butylated hydroxytoluene (RS-BHT). The three monoterpenes (carvacrol, sabinene hydrate and thymol) provided protection to this food product, inhibiting the formation of oxidative deterioration compounds such as peroxides and hexanal and undesirable off-flavors such as oxidized and cardboard flavors. Sabinene hydrate had greater effect preventing peroxide formation during storage than the other monoterpenes. CONCLUSION: Carvacrol, sabinene hydrate and thymol could be used as an alternative to synthetic antioxidants for preserving the quality of roasted sunflower seeds.