RESUMO
BACKGROUND: Tree-ripe mangoes are of a better quality than the more commonly marketed mature-green fruit. However, the postharvest life of tree-ripe mangoes at the chilling threshold temperature for mature-green fruit of 12 °C is insufficient to allow long distance transport for international marketing. Because the chilling sensitivity often decreases as fruit ripen, lower temperatures (5 and 8 °C) in combination with a controlled atmosphere of 5 kPa O2 plus 10 or 25 kPa CO2 were tested to determine whether the quality of tree-ripe mangoes could be maintained longer without chilling injury (CI). RESULTS: Tree-ripe 'Tommy Atkins' and 'Keitt' mangoes were stored for 14 or 21 days, respectively, in air or controlled atmosphere (CA) at 5 or 8 °C. Respiration rates were below 10 mL kg-1 h-1 during CA storage and increased three-fold during a 3-day shelf life period at 20 °C. Ethanol synthesis of fruit stored in 25 kPa CO2 , but not 10 kPa CO2 , increased during storage and remained high during shelf life, indicating physiological stress. Elevated electrolyte leakage and 1-aminocyclopropane-1-carboxylic acid concentrations in both cultivars stored in 25 kPa CO2 also indicated that mesocarp tissues were injured by the higher CO2 level. No CI symptoms were observed in air or CA at either 5 or 8 °C. CONCLUSION: Storage of tree-ripe mangoes in 5 kPa O2 plus 10 kPa CO2 at either 5 or 8 °C best maintained the quality of Tommy Atkins and Keitt fruit for 14 or 21 days, respectively, without evidence of either atmosphere injury or CI. © 2020 Society of Chemical Industry.
Assuntos
Dióxido de Carbono/análise , Armazenamento de Alimentos/métodos , Mangifera/química , Armazenamento de Alimentos/instrumentação , Frutas/química , Controle de Qualidade , TemperaturaRESUMO
This work evaluated the presence of contaminants in stored rainwater in 36 polyethylene tanks installed in two rural communities of the semiarid of Bahia, Brazil. Carbonyl compounds were analyzed by High Performance Liquid Chromatography (HPLC-UV), BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) by gas chromatoghaphy (GC-FID), and trace elements by inductively coupled plasma optical emission spectrometry (ICP-OES). Seven carbonyl compounds were quantified including acrolein (<3-115⯵gâ¯L-1), which is considered a potent mutagenic agent, above the potability limit in 75% of the cases. Trace elements such as copper, zinc, barium, aluminum and lead, more frequently found, were also quantified, and lead (<0,56-99⯵gâ¯L-1) was above the tolerable limit for drinking water of 10⯵gâ¯L-1 in 73% of the cases. The results show that the stored water in polyethylene cisterns in the Brazilian semiarid region does not present satisfactory conditions for human consumption.
Assuntos
Água Potável/análise , Polietileno , Poluentes Químicos da Água/análise , Acroleína/análise , Benzeno/análise , Derivados de Benzeno/análise , Brasil , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Água Potável/química , Armazenamento de Alimentos/instrumentação , Armazenamento de Alimentos/métodos , Metais/análise , Análise Espectral/métodos , Tolueno/análise , Xilenos/análiseRESUMO
Two polysaccharides (PS), gum arabic (GA) and sodium alginate (SA), and whey protein concentrate (WPC) were used to design bio-based films at two ratios (RPS:WPC, 1:2 and 1:3). The effects of PS, RPS:WPC and WPC thermal treatment (unheated vs. aggregate) were determined on films characteristics. Film-forming dispersions were tested using different complementary techniques: UV-Vis spectroscopy, electrophoretic mobility, bulk rheology and confocal microscopy. PS exhibited weak associations with proteins. However, this behavior was more significative in SA/WPC systems. Rheological and optical characteristics of filmogenic suspensions were influenced by PS, RPS:WPC and WPC heat treatment. Apparent viscosity values for SA/WPC systems were 80-250 times higher than the ones obtained for GA/WPC systems. Furthermore, thickness, moisture absorption, contact angle and mechanical properties were also affected by the film design factors. GA/WPC-aggregates films showed lesser moisture absorption; however, they have higher surface polarity than those made with SA/WPC-aggregates. Moreover, SA/WPC-aggregates systems provided stronger films in comparison with the GA/WPC-aggregates ones. In addition, mechanical properties were also affected by RPS:WPC and WPC treatment. It was observed that denatured WPC and 1:3 RPS:WPC produced weaker mechanical features. Results provide useful information for the design of bio-based mixed films with tailor-made properties.
Assuntos
Alginatos/química , Plásticos Biodegradáveis/química , Goma Arábica/química , Proteínas do Soro do Leite/química , Armazenamento de Alimentos/instrumentação , Humanos , Teste de Materiais , Membranas Artificiais , Reologia , Viscosidade , MolhabilidadeRESUMO
BACKGROUND: Brazilians and Slovakians evaluated the temporal profile and the acceptability of cachaça stored with different woods (Cumarurana (CM), Jatobá (JT) and, Louro-vermelho (LV), which are found in the Amazon rainforest, and also oak), with the aim of performing a cross-cultural comparison of the dynamic profile of the attributes perceived in the cachaças and the sensorial acceptance of the samples. RESULTS: Important differences were observed between the temporal sensorial profiles generated by the two groups and their preferences. Brazilians preferred cachaças stored with the traditional wood, oak, followed by those stored with JT and CM. In contrast, Slovakians preferred cachaças stored with JT, followed by those stored with LV and oak. For both countries, the dominance of wood flavor and vanilla attributes at the end of the analysis time was positively associated with acceptance, while the dominance of off-flavors and the wood flavor attribute at the beginning of the analysis time was negatively associated with acceptance for Brazilians and Slovakians, respectively. CONCLUSION: Brazilians preferred cachaça stored with oak wood, and Slovakians preferred cachaça stored with JT wood, with acceptability being strongly associated with the dominance of wood flavor and vanilla attributes at the end of the evaluation time. © 2018 Society of Chemical Industry.
Assuntos
Bebidas Alcoólicas/análise , Comportamento do Consumidor , Armazenamento de Alimentos/instrumentação , Madeira/química , Adulto , Brasil , Comparação Transcultural , Dipteryx/química , Feminino , Humanos , Hymenaea/química , Masculino , Pessoa de Meia-Idade , Saccharum/química , Eslováquia , Paladar , Adulto JovemRESUMO
The stability of vitamins A, E, and C was determined in 12 brands of vitamin supplements over a 12-month storage period. The variations in concentrations of these vitamins across three different batches of five brands were measured. Vitamins A and E was determined by HPLC method, and vitamin C was measured by using potentiometric titration. All samples for stability studies were maintained at room temperature and protected from light. Measurements were carried out in the first semester of the expiration date and then every six months up to 12 months of storage. After this period, only one sample showed no significant decrease in vitamin A and E concentrations in relation to the concentrations measured at the beginning of the study. The concentration of vitamin C showed no significant decrease in 50% of the samples after 6 months of storage, although after 12 months, 92% had significant losses in concentration. The analysis of the different batches showed significant variations in the vitamin levels, which do not seem to be significant for inspection purposes considering the tolerance outlined in the legislation. Over-fortification of vitamin supplements during manufacture seems to be required, but the additional amount of supplementation will depend on each sample.
Assuntos
Vitamina A/análise , Rotulagem de Produtos/normas , Ácido Ascórbico/análise , Vitamina E/análise , Suplementos Nutricionais/efeitos adversos , Armazenamento de Alimentos/instrumentação , Provitaminas/classificaçãoRESUMO
The objective of this study was to evaluate 2 systems for covering corn silage in bunker silos. The first system consisted of a sheet of 45-µm-thick oxygen barrier film (OB, polyethylene + ethylene-vinyl alcohol) placed along the length of the sidewall before filling. After filling, the excess film was pulled over the wall on top of the silage, and a sheet of polyethylene was placed on top. The second system involved using a standard sheet (ST) of 180-µm-thick polyethylene film. Eight commercial bunker silos were divided into 2 parts lengthwise so that one-half of the silo was covered with OB and the other half with a ST system. During the filling, 3 net bags with chopped corn were buried in the central part (halfway between the top and bottom of the silo) of the bunkers (CCOR) in 3 sections 10 m apart. After filling, 18 net bags (9 per covering system) were buried 40 cm below the top surface of the 3 sections. These bags were placed at 3 distances from the bunker walls (0 to 50 cm, 51 to 100 cm, and 101 to 150 cm). During unloading, the bags were removed from the silos to determine the dry matter (DM) losses, fermentation end products, and nutritive value. The Milk2006 spreadsheet was used to estimate milk per tonne of DM. The model included the fixed effect of treatment (7 different locations in the bunker) and the random effect of the silo. Two contrasts were tested to compare silages in the top laterals (shoulders) with that in the CCOR (CCOR vs. OB and CCOR vs. ST). Three contrasts compared the corresponding distances of the silage covered by the 2 systems (OB50 vs. ST50, OB100 vs. ST100 and OB150 vs. ST150). Variables were analyzed with the PROC MIXED procedure of the SAS at the 5% level. The OB method produced well-fermented silages, which were similar to CCOR, whereas the OB system showed less lactic acid and greater pH and mold counts compared with CCOR. The ST method had 116.2 kg of milk/t less than the CCOR, as the OB system and the CCOR were similar (1,258.3 and 1,294.0 kg/t, respectively). Regarding the distances from the walls, the effects were more pronounced from 0 to 101 cm. The OB50 and OB100 silages had better quality and lower mold counts and DM losses than ST50 and ST100. The OB system reduced DM and nutrient losses at the shoulders in farm bunker corn silages compared with no sidewall plastic. The OB film should lap onto the crop for at least 200 cm so that 150 cm are covered outward from the wall.
Assuntos
Fermentação , Armazenamento de Alimentos/métodos , Valor Nutritivo , Oxigênio , Plásticos/química , Silagem , Zea mays , Criação de Animais Domésticos , Animais , Etanol , Armazenamento de Alimentos/instrumentação , Concentração de Íons de Hidrogênio , Ácido Láctico/análise , Polietileno , Compostos de VinilaRESUMO
OBJECTIVES: Lead exposure remains a significant environmental problem; lead is neurotoxic, especially in developing humans. In Mexico, lead in human blood is still a concern. Historically, much of the lead exposure is attributed to the use of handcrafted clay pottery for cooking, storing and serving food. However, experimental cause-and-effect demonstration is lacking. The present study explores this issue with a prospective experimental approach. METHODS: We used handcrafted clay containers to prepare and store lemonade, which was supplied as drinking water to pregnant rats throughout the gestational period. RESULTS AND DISCUSSION: We found that clay pots, jars, and mugs leached on average 200â µg/l lead, and exposure to the lemonade resulted in 2.5â µg/dl of lead in the pregnant rats' blood. Neonates also showed increased lead content in the hippocampus and cerebellum. Caspase-3 activity was found to be statistically increased in the hippocampus in prenatally exposed neonates, suggesting increased apoptosis in that brain region. Glazed ceramics are still an important source of lead exposure in Mexico, and our results confirm that pregnancy is a vulnerable period for brain development.
Assuntos
Silicatos de Alumínio/química , Utensílios de Alimentação e Culinária , Exposição Dietética/efeitos adversos , Contaminação de Alimentos , Armazenamento de Alimentos/instrumentação , Intoxicação do Sistema Nervoso por Chumbo/etiologia , Chumbo/toxicidade , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Citrus/química , Argila , Feminino , Sucos de Frutas e Vegetais/efeitos adversos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Chumbo/sangue , Chumbo/metabolismo , Intoxicação do Sistema Nervoso por Chumbo/sangue , Masculino , Exposição Materna/efeitos adversos , México , Gravidez , Distribuição Aleatória , Ratos Wistar , Distribuição Tecidual , ToxicocinéticaRESUMO
The purpose of this study was to determine the microbiological air quality (psychrotrophic bacteria and airborne fungi) and distribution of fungi in different types of ready-to-eat (RTE) food-storage refrigerators (n=48) at selected retail stores in the city of Edirne, Turkey. Refrigerators were categorized according to the type of RTE food-storage: meat products, vegetables, desserts, or a mix of food types. Microbiological quality of air samples was evaluated by using a Mas-100 Eco Air Sampler. Four refrigerators (all containing meat products, 8.3%) produced air samples with undetectable microorganisms. The highest detected mean value of airborne psychrotrophic bacteria and fungi was 82.3 CFU/m³ and 54.6 CFU/m³, respectively and were found in mixed-food refrigerators. The dominant airborne fungal genera found were Penicillium (29.0%), Aspergillus (12.0%), Mucor (9%), Cladosporium (8%), Botyrtis (7%), and Acremonium (6%). By definition, RTE food does not undergo a final treatment to ensure its safety prior to consumption. Therefore, ensuring a clean storage environment for these foods is important to prevent food-borne disease and other health risks.(AU)
Assuntos
Animais , Bactérias/crescimento & desenvolvimento , Alimentos , Armazenamento de Alimentos/instrumentação , Fungos/crescimento & desenvolvimento , RefrigeraçãoRESUMO
The objective of this study was to evaluate the shelf life of powdered guavira pulp obtained by a foam mat drying process. The dehydrated guavira pulp was packed into low density polyethylene (LDPE) bags and stored under two controlled conditions: environmental (25°C, RH 75%) and accelerated (35°C, RH 90%) for 90 days. The shelf life was accompanied by carrying out the following analyses every 10 days: moisture content, water activity, vitamin C content, pH and titratable acidity. Vitamin C was the quality attribute used to determine the shelf life of the product, by determining its degradation kinetics as a function of storage time. The linear regression data showed that the vitamin C degradation reaction fitted the zero and first order kinetic models. The shelf life of the powdered guavira pulp under environmental conditions was approximately 49 days, and under accelerated conditions (35°C) 45 days. The Q10 was equal to 1.09, predicting a shelf life similar to that found under environmental conditions. The moisture content for these conditions was 10.0% e 5.4% for 35°C and 25°C, respectively. The above demonstrate the efficiency of the accelerated test in predicting the shelf life of the product.