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The purpose of this study was to determine PM₂.₅ mass concentration and the contents of trace elements and water-soluble ions in samples collected inside the Metropolitan area of Huancayo. Four monitoring stations were installed at three urban areas (UNCP, HYO, and CHI) and one rural (IGP). The sampling campaign was carried out from March 2017 to November 2017. The PM₂.₅ content was determined by gravimetric method, and fifteen trace elements (TE) and seven water-soluble ions were detected by inductively coupled plasma mass spectrometry (ICP–MS), and ion chromatography (IC), respectively. Datasets were assessed by one ANOVA test to detect significant differences among monitoring station. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were applied for source identification. The mean annual concentration of PM₂.₅ mass concentrations has ranged (ave...
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Background. Artichoke (Cynara scolymus L.) residues are a rich source of phenolic compounds, but these compounds are susceptible to external factors. Therefore, nanoencapsulation by ionic and ultrasound-assisted gelation techniques can be used as an alternative to preservation. This work aimed to determine the effects of the interaction of the following variables: chitosan (Ch) concentration, sodium tripolyphosphate (TPP), Ch/TPP ratio, pH, and sonication time to ensure high encapsulation efficiency (%EE). Materials and methods. Optimal nanoencapsulation conditions were evaluated using a 25–1 fractional factorial design to maximize nanoencapsulation efficiency (%EE) using multivariate regression analysis. Results. The model was adequate with R2 = 0.998. The optimum conditions for nanoencapsulation were Ch (0.28%), TPP (0.29%), Ch/TPP (5/1), pH (4.9) and sonication time (4.79 min). Unde...
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The research aimed to develop a children's pumpkin compote, functional, inexpensive, preservative-free and of considerable shelf life. The effect of incorporating xanthan gum (XG) was evaluated at three concentrations (0.10%, 0.15% and 0.20%) on its rheological properties. Sensory characteristics were applied to 60 panelists (30 undergraduate students and 30 children between 2 and 3 years). Its physical, physicochemical, and microbiological characteristics were determined. With the pH values was estimated the shelf life of pumpkin compote using accelerated testing method. The product was stored at 20 °C, 30 °C and 40 °C for 0, 10, 20, and 30 days. The results show the pumpkin compote presented non-Newtonian behavior, pseudoplastic, and was adjusted to the Ostwald Waele model (R2 > 0.98). Compote formulated with 0.15% of XG was conceived as the best treatment, with a "Like" scale fo...
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artículo
The research aimed to develop a children's pumpkin compote, functional, inexpensive, preservative-free and of considerable shelf life. The effect of incorporating xanthan gum (XG) was evaluated at three concentrations (0.10%, 0.15% and 0.20%) on its rheological properties. Sensory characteristics were applied to 60 panelists (30 undergraduate students and 30 children between 2 and 3 years). Its physical, physicochemical, and microbiological characteristics were determined. With the pH values was estimated the shelf life of pumpkin compote using accelerated testing method. The product was stored at 20 °C, 30 °C and 40 °C for 0, 10, 20, and 30 days. The results show the pumpkin compote presented non-Newtonian behavior, pseudoplastic, and was adjusted to the Ostwald Waele model (R2 > 0.98). Compote formulated with 0.15% of XG was conceived as the best treatment, with a "Like" scale fo...
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Rice (Oryza sativa L) is an important source of essential elements but also can contain high As concentrations, which may be consumed and causes health effects. This work aimed to contribute to the lack of information quantifying the total arsenic (tAs) in 31 domestic rice (white rice, n=19; brown rice, n=7; parboiled rice, n=5) of different brands purchased in Peruvian markets. The tAs content was conducted by ICP-MS. The tAs concentration was compared to the maximum limits prescribed by regulatory agencies. Dietary intake (DI), dietary exposure (DE), and margin of exposure (MOE) were estimated. tAs concentration in white, brown and parboiled rice were 0.292 ± 0.106 mg/kg, 0.401 ± 0.081 mg/kg, 0.229 ± 0.03 mg/kg, respectively. Arsenic concentration in white rice exceeded limits recommended by FAO/WHO (0.20 mg kg-1), and European legislation (0.25 mg kg-1), but no Mercosul limits (0.3...
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Theobroma cacao is the main raw material to produce chocolate, as well as for use in the food, cosmetic, and pharmaceutical industries. However, Moniliophthora roreri is one of the most destructive fungal diseases and the main limiting of cacao production worldwide. Thus, this work aimed to assess the inhibitory effect of extracts of Zingiber officinale (T1) and Aloe vera (T2), and Trichoderma harzianum + Bacillus subtillis. (T3) on Moniliophthora roreri infection in Theobroma cacao; in addition, a control (T4) was also evaluated. Each treatment was applied to six plants of cacao. Incidence of monilia infection and fruit weight were monitored every 15 days (in total four periods) after the application of the treatment by spray. Significant differences (P<0.05) were found among treatments for incidence. It was observed that spraying entire cacao trees after two times (approximately 30 day...
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Rice (Oryza sativa L) is an important source of essential elements but also can contain high As concentrations, which may be consumed and causes health effects. This work aimed to contribute to the lack of information quantifying the total arsenic (tAs) in 31 domestic rice (white rice, n=19; brown rice, n=7; parboiled rice, n=5) of different brands purchased in Peruvian markets. The tAs content was conducted by ICP-MS. The tAs concentration was compared to the maximum limits prescribed by regulatory agencies. Dietary intake (DI), dietary exposure (DE), and margin of exposure (MOE) were estimated. tAs concentration in white, brown and parboiled rice were 0.292 ± 0.106 mg/kg, 0.401 ± 0.081 mg/kg, 0.229 ± 0.03 mg/kg, respectively. Arsenic concentration in white rice exceeded limits recommended by FAO/WHO (0.20 mg kg-1), and European legislation (0.25 mg kg-1), but no Mercosul limits (0.3...
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Rice (Oryza sativa L) is an important source of essential elements but also can contain high As concentrations, which may be consumed and causes health effects. This work aimed to contribute to the lack of information quantifying the total arsenic (tAs) in 31 domestic rice (white rice, n=19; brown rice, n=7; parboiled rice, n=5) of different brands purchased in Peruvian markets. The tAs content was conducted by ICP-MS. The tAs concentration was compared to the maximum limits prescribed by regulatory agencies. Dietary intake (DI), dietary exposure (DE), and margin of exposure (MOE) were estimated. tAs concentration in white, brown and parboiled rice were 0.292 ± 0.106 mg/kg, 0.401 ± 0.081 mg/kg, 0.229 ± 0.03 mg/kg, respectively. Arsenic concentration in white rice exceeded limits recommended by FAO/WHO (0.20 mg kg-1), and European legislation (0.25 mg kg-1), but no Mercosul limits (0.3...
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The effect of including whey in the diet of rams in the fattening stage of the company SAIS Pachacutec S.A.C, located in the central mountains of Peru at an altitude of 4119 m was evaluated. In total, 120 five-month-old Corriedale male rams from the “Cabaña” (n=40), “Plantel” (n=40) and “Majada” (n=40) genetic sections were used. Rams from each section was randomly distributed into four treatment groups (n=10 per group): T1 (0%, control); T2 (15%); T3 (25%) and T4 (35% whey). The whey was added to the concentrate (bran feed). The study included 14 days of adaptation to the feed and 90 days of trial. Final weight, weight gain and carcass weight were significantly different between treatments and sections (p<0.05), being greater in T4 and in the Cabaña section (final weight: 48.7 ± 0.6 kg; weight gain: 379.4 g/day; carcass weight: 20.9 ± 1.2 kg). Carcass yield was simila...
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A total of 188,859 meteorological-PM10 data validated before (2019) and during the COVID-19 pandemic (2020) were used. In order to predict PM10 in two districts of South Lima in Peru, hourly, daily, monthly and seasonal variations of the data were analyzed. Principal Component Analysis (PCA) and linear/nonlinear modeling were applied. The results showed the highest annual average PM10 for San Juan de Mirafores (SJM) (PM10-SJM: 78.7 µg/m3) and the lowest in Santiago de Surco (SS) (PM10 -SS: 40.2 µg/m3). The PCA showed the infuence of relative humidity (RH)-atmospheric pressure (AP)temperature (T)/dew point (DP)-wind speed (WS)-wind direction (WD) combinations. Cool months with higher humidity and atmospheric instability decreased PM10 values in SJM and warm months increased it, favored by thermal inversion (TI). Dust resuspension, vehicular transport and stationary sources contributed m...