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1.
An Acad Bras Cienc ; 91(3): e20180447, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576913

RESUMO

In this study effects of ultrasonic pretreatment with different sonication sources on drying behavior of carrot slices were evaluated. Fresh carrot slices were pretreated with ultrasonic probe at 65, 75 and 85 W or ultrasonic bath at 10, 20 and 30°C for 3, 5 and 10 min before air drying. Water gain % and solid loss % of pretreated samples were calculated and color values, ß-carotene content and rehydration ratios of dried samples were determined. Drying behavior of the pretreated samples was evaluated and the drying data were fitted to thin layer drying models. Constant drying rate period was not observed for the carrot slices; however two definite falling-rate periods having different slopes were obtained. Drying time was significantly reduced (up to 20%) depending on the type of pretreatment. The redness value, total color difference and Chroma values of pretreated and control samples were in the same group (p>0.05). ß-carotene content of ultrasonic bath pretreated samples were significantly higher than the samples pretreated with ultrasonic probe and the sample dried without any pretreatment as well (p<0.05). Also rehydration ratios of control samples were found lower than the ultrasound pretreated samples.


Assuntos
Daucus carota/efeitos da radiação , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Ondas Ultrassônicas , Algoritmos , Análise de Variância , Cor , Daucus carota/química , Cinética , Valores de Referência , Reprodutibilidade dos Testes , Sonicação/métodos , Fatores de Tempo , beta Caroteno/análise , beta Caroteno/efeitos da radiação
2.
J Agric Food Chem ; 67(38): 10624-10636, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31483633

RESUMO

The freshness and color quality of postharvest tea leaves can be markedly prolonged and retained by proper preservation measures. Here, we investigated the dynamic changes of chlorophyll and its derivatives in postharvest tea leaves under different low-temperature treatments using natural withering as a control. Chlorophyll decomposition was found closely related with chlorophyllide, pheophorbide, and pheophytin. Low-temperature withering could slow chlorophyll degradation in postharvest tea leaves via significant inhibition on the enzyme activity and gene expression of Mg-dechelatase, chlorophyllase, and pheophorbide a oxygenase. At the initial stage of withering, a significant increase was observed in the chlorophyll content, expression of chlorophyll-synthesis-related enzymes (such as glutamyl-tRNA synthetase, etc.), and chlorophyll synthase activity in newly picked tea leaves. Moreover, an obvious decrease was found in the content of l-glutamate as the foremost precursor substance of chlorophyll synthesis. Hence, our findings revealed that the chlorophyll synthesis reaction was induced by the light-dehydration-stress in the initial withering of tea leaves. This study provides a theoretical basis for exploring preservation technology in actual green tea production.


Assuntos
Camellia sinensis/genética , Camellia sinensis/metabolismo , Clorofila/metabolismo , Manipulação de Alimentos/métodos , Regulação da Expressão Gênica de Plantas , Camellia sinensis/química , Camellia sinensis/crescimento & desenvolvimento , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Clorofila/química , Cor , Enzimas/genética , Enzimas/metabolismo , Oxigenases/genética , Oxigenases/metabolismo , Folhas de Planta/química , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Temperatura Ambiente
3.
J Sci Food Agric ; 99(14): 6649-6654, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31368529

RESUMO

BACKGROUND: This study evaluated the degradation of pyrrolizidine alkaloids (PAs) from eastern groundsel (Senecio vernalis) in grass silage prepared with different inoculants. Silages were produced from ryegrass with 230 g kg-1 dry matter (DM) content and mixed with eastern groundsel (9:1; w/w fresh matter basis) containing 5.5 g kg-1 DM PA. Treatments were: CON (untreated control), LP (3.0 × 105 cfu g-1 Lactobacillus plantarum DSMZ 8862/8866) or LBLC (7.3 × 104 cfu g-1 Lactobacillus buchneri LN40177 / Lactobacillus casei LC32909), and each of the treatments in combination with 30 g kg-1 molasses. Silages were prepared in glass jars and opened after 3, 10, and 90 days. Fermentation characteristics were determined and the PAs analyzed. RESULTS: Although the levels of fermentation acids differed between treatments, results indicated good quality of all silages during 90 days. Significant time (P < 0.001) and treatment (P < 0.001) effects were observed for PAs. Concentrations of senecionine and seneciphylline decreased with molasses, declined over time, and were negatively correlated with lactic, propionic, and butyric acid, or with lactic and butyric acid in case of seneciphylline. In all silages, seneciphylline and senecionine N-oxides were undetectable after 3 days, whereas senkirkine, the most abundant PA, remained stable. CONCLUSIONS: Silage prepared from grass contaminated with eastern groundsel still contained high PA levels, and was hence a potential health hazard. Molasses supplementation reduced concentrations of senecionine and seneciphylline, while the bacterial inoculants had no effect. Other potentially toxic PA metabolites were not analyzed in the present study and further research is needed. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ração Animal/análise , Manipulação de Alimentos/métodos , Lolium/química , Alcaloides de Pirrolizidina/química , Senécio/química , Silagem/análise , Ração Animal/microbiologia , Fermentação , Lactobacillus/metabolismo , Lactobacillus plantarum/metabolismo , Lolium/microbiologia , Melaço/análise , Alcaloides de Pirrolizidina/metabolismo , Alcaloides de Pirrolizidina/toxicidade , Senécio/toxicidade , Silagem/microbiologia
4.
J Agric Food Chem ; 67(36): 10185-10194, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31423782

RESUMO

This research aimed to measure the impact of novel food processing techniques, i.e., pulsed electric field (PEF) and ohmic heating (OH), on carotenoid bioaccessibility and Caco-2 cell uptake from tomato juice and high-pressure processing (HPP) and PEF on the same attributes from kale-based juices, as compared with raw (nonprocessed) and conventional thermally treated (TT) juices. Lycopene, ß-carotene, and lutein were quantitated in juices and the micelle fraction using high-performance liquid chromatography (HPLC)-diode array detection and in Caco-2 cells using HPLC-tandem mass spectrometry. Tomato juice results were as follows: PEF increased lycopene bioaccessibility (1.5 ± 0.39%) by 150% (P = 0.01) but reduced ß-carotene bioaccessibility (28 ± 6.2%) by 44% (P = 0.02), relative to raw juice. All processing methods increased lutein uptake. Kale-based juice results were as follows: TT and PEF degraded ß-carotene and lutein in the juice. No difference in bioaccessibility or cell uptake was observed. Total delivery, i.e., the summation of bioaccessibility and cell uptake, of lycopene, ß-carotene, and lutein was independent of type of processing. Taken together, PEF and OH enhanced total lycopene and lutein delivery from tomato juice to Caco-2 cells as well as TT, and may produce a more desirable product due to other factors (i.e., conservation of heat-labile micronutrients, fresher organoleptic profile). HPP best conserved the carotenoid content and color of kale-based juice and merits further consideration.


Assuntos
Brassica/química , Carotenoides/metabolismo , Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Lycopersicon esculentum/química , Preparações de Plantas/metabolismo , Transporte Biológico , Brassica/metabolismo , Células CACO-2 , Temperatura Alta , Humanos , Lycopersicon esculentum/metabolismo , Modelos Biológicos , Preparações de Plantas/química
5.
J Agric Food Chem ; 67(33): 9295-9306, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31365237

RESUMO

As a result of an innovative olive fruit processing method involving stone removal and dehydration, a new kind of olive oil and olive flour are generated. The main objective of this work was to accomplish the comprehensive characterization of the minor compounds of both products and to evaluate the effect of the dehydration temperature on their composition. To this end, olive oil and flour samples obtained through the novel processing method were analyzed and compared with "conventional" virgin olive oils (VOO). The applied LC-MS methodology allowed the determination of 57 metabolites belonging to different chemical classes (phenolic compounds, pentacyclic trirterpenes, and tocopherols). Both the new oils and flours presented considerable amounts of olive fruit metabolites that are usually absent from VOO. Quantitative differences were found among VOOs and the new oils, probably due to the inhibition of some enzymes caused by the temperature increase or the absence of water during the processing.


Assuntos
Manipulação de Alimentos/métodos , Olea/química , Extratos Vegetais/química , Resíduos/análise , Cromatografia Líquida , Farinha/análise , Frutas/química , Azeite de Oliva/análise , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas em Tandem , Tocoferóis/química , Tocoferóis/isolamento & purificação
6.
J Sci Food Agric ; 99(14): 6546-6551, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31328269

RESUMO

BACKGROUND: Proteins recovery using hydrochloric acid (HCl) in acid-aided solubilization could cause greater loss in its functionality over alkali-aided solubilization. Moreover, using HCl in edible foods is also a health concern. Replacing HCl with organic acids for acid-aided solubilization could address these problems. The aim was to study the effect of organic acid (glacial acetic acid) as a replacement for HCl during pH shift processing on the characteristics and functionality of rohu (Labeo rohita) protein isolates. Rohu proteins were obtained by solubilizing at pH 3.0 and pH 11.0 using glacial acetic acid and sodium hydroxide (10 mol L-1 ). RESULTS: Results showed that solubilization at pH 11.0 gave higher protein yields (766.8 ± 2.4 g kg-1 ) compared to solubilization at pH 3.0 (735.7 ± 7.1 g kg-1 ) (P < 0.05). Isolates from acid-aided solubilization had higher whiteness and total pigment content over isolates obtained by alkali-aided solubilization. Rohu isolates recovered by alkaline solubilization showed higher water and oil holding capacity, gel strength, folding scores, foaming and emulsion capacity than acid processed isolates (P < 0.05). Solubilization of rohu proteins using glacial acetic acid produced isolates with low breaking force (149.0 g), low storage modulus (G') values and low folding test score (1.0) over the alkaline isolates (P < 0.05). CONCLUSION: Results indicated that, recovering rohu proteins using organic acid (glacial acetic acid) could produce isolates with poor functional properties, while using the organic acid to precipitate the proteins solubilized by alkali-aided processing could produce proteins with better yields and functionality. © 2019 Society of Chemical Industry.


Assuntos
Fracionamento Químico/métodos , Proteínas de Peixes/isolamento & purificação , Manipulação de Alimentos/métodos , Ácido Acético/química , Animais , Cyprinidae , Proteínas de Peixes/química , Concentração de Íons de Hidrogênio , Solubilidade
7.
J Dairy Sci ; 102(9): 7734-7746, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31279555

RESUMO

This study investigated the ultrastructural changes underlying the undesired softening of insufficiently acidified feta cheese during cold storage. Experimental feta cheeses with a range of pH values before brining were manufactured by allowing the cheese blocks to ferment overnight at 3 temperatures (35, 20, and 3°C), which resulted in pH values of 4.80, 4.88, and 5.17, respectively. Cheese blocks were stored in pH-adjusted whey brine solutions for up to 120 d, at which point significant decreases in the cheese firmness were confirmed with compression and shear tests. Samples for transmission electron microscopy were taken during the make procedure, after overnight fermentation, and after 7 and 90 d of cold storage. Increasing the initial pH from 4.80 to 5.17 resulted in a fundamentally different ultrastructure at d 90, with the protein matrix as the continuous phase having markedly decreased density compared with the typically open porous and discontinuous protein matrix of high density in the low-pH control feta cheese. Ultrastructural changes were progressive, and the first signs were evident after only 20 h (the overnight fermentation), when fine, proteinaceous material dissociated from the edges of the casein strands into the serum phase. By d 7, the serum phase was completely filled with the loosely aggregated casein closely surrounding the spheroidal fat globules. A further breakdown of the protein matrix was observed after 90 d, with the complete loss of open porous network structure. Image analysis quantitatively confirmed the progressive and significant decrease in density of the protein matrix. In summary, this is the first study to provide a comprehensive and in-depth view of the progressive and most likely irreversible ultrastructural changes that lead to this textural defect.


Assuntos
Caseínas/ultraestrutura , Queijo/análise , Manipulação de Alimentos/métodos , Animais , Caseínas/química , Bovinos , Temperatura Baixa , Fermentação , Armazenamento de Alimentos/métodos , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão
8.
J Dairy Sci ; 102(9): 7697-7706, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31326167

RESUMO

Nutrition plays a crucial role in human gut health through the improvement of gut barrier functionality. Donkey milk represents an interesting source of natural antimicrobial factors such as lysozyme. Recently, anti-inflammatory properties of donkey milk lysozyme activity were described in a mouse model of ileitis. The current increase of donkey milk consumption highlights the necessity to propose a healthy milk compliant with microbiological standards. This study aims to define a heat treatment of donkey milk, retaining its high lysozyme activity, and to evaluate its beneficial effects on a gut barrier impairment model due to chronic stress in mice. To perform this experiment, samples of raw donkey milk were collected in 15 distinct French farms. Microbiological analysis and lysozyme content and activity were evaluated for each sample. Then, several heat treatments were carried out to define a time and temperature combination that allowed for both a reduction in the number of total micro-organisms, increasing the shelf-life of the product, and preservation of lysozyme activity. The beneficial effect of heated donkey milk on the gut barrier of mice was evaluated and compared with raw donkey milk. We found that samples of raw donkey milk showed low total mesophilic microbial counts, and no pathogens were detected. Among the different heat-treatment procedures tested, a 2-min, 72°C combination was determined to be the most optimal time and temperature combination to preserve lysozyme activity and increase the shelf-life of donkey milk. Oral administration of this heat-treated donkey milk in mice counteracted chronic stress-induced intestinal damage, illustrated by gut hyper-permeability and low-grade inflammation, similar to raw donkey milk. We have demonstrated for the first time that oral intervention with donkey milk, optimally heat-treated to retain enzymatic lysozyme activity, improves intestinal barrier damage linked to psychological stress in mice.


Assuntos
Equidae , Temperatura Alta , Mucosa Intestinal/fisiologia , Leite/enzimologia , Muramidase/metabolismo , Estresse Fisiológico/fisiologia , Animais , Anti-Inflamatórios , Aprendizagem da Esquiva , Manipulação de Alimentos/métodos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Leite/microbiologia , Muramidase/farmacologia , Permeabilidade/efeitos dos fármacos , Água
9.
J Food Sci ; 84(8): 2313-2324, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313314

RESUMO

This study was the first to evaluate the influence of herb addition in a complex food matrix processed by microwave-assisted thermal sterilization (MATS) system for potential salt reduction implications. In a chicken pasta meal, salt concentrations included 100% (full salt) and reduced salt variations (75%, 50%, and 25% of the original salt concentration) and for each meal, a version with and without herb addition. The influence of storage time on sensory perception and acceptance was investigated, along with the odor-induced saltiness enhancement (OISE). Trained sensory panel results showed that the addition of herbs to the chicken pasta meal increased the intensity of many flavors and led to an increased saltiness perception, demonstrating their congruency with salty taste. The addition of herbs allowed for a 50% salt reduction in a processed prepared meal while maintaining the same intensity of saltiness perception as determined by a trained panel and overall meal acceptance by consumers. The OISE was only significant for the 25% salt meal (P < 0.05) suggesting that the influence of herb addition on saltiness perception at lower salt concentrations was more influential than at higher salt concentrations. Over longer storage times, meals processed by MATS and stored at ambient temperature increased in aroma, taste, and flavor intensities as well as in acceptance of many meal attributes. This study contributed an additional strategy of product reformulation, specifically herb addition, to the portfolio of salt-reduction strategies for prepared meals using MATS. PRACTICAL APPLICATION: The addition of herbs to prepared meals (chicken pasta) may allow for up to a 50% reduction in salt content while maintaining the same saltiness intensity perception and overall consumer acceptance. This has important implications for the food industry as sodium reduction is a complex task. Furthermore, the additional herbs utilized in this study increased the intensity of certain aromas and flavors, and led to increased saltiness perception; these herbs could be considered in future salt reduction applications as this study demonstrates their congruency with salty taste.


Assuntos
Aditivos Alimentares/análise , Manipulação de Alimentos/métodos , Carne/análise , Especiarias/análise , Percepção Gustatória , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Galinhas , Feminino , Aromatizantes/análise , Manipulação de Alimentos/instrumentação , Preferências Alimentares , Temperatura Alta , Humanos , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Odorantes/análise , Cloreto de Sódio na Dieta/análise , Esterilização , Paladar , Adulto Jovem
10.
J Sci Food Agric ; 99(14): 6500-6508, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31321768

RESUMO

BACKGROUND: Emulsification is important for food quality and processing functionality. Most emulsification occurs under high-fat conditions that eventually cause health concerns. Protein emulsifiers also have drawbacks such as lower dispersity. This study considered the effects of different high-speed shear homogenization (HSH) speeds on the emulsifying and structural properties of myofibrillar proteins (MPs) under low-fat conditions. RESULTS: High-speed shear homogenization significantly increased the emulsifying activity and emulsifying stability of MPs at lower speeds (8000 to 14 500 rpm). The primary structure of MP was not altered significantly by HSH, whereas its secondary, tertiary, and quaternary structures were changed. Particle size decreased first and then increased significantly, and reached a minimum when the HSH speed was 14 500 rpm. The absolute zeta potential values increased significantly and the dendritic fibrous structure of sample was destroyed when the speed exceeded 14 500 rpm. High-speed shear homogenization (14 500 rpm) decreased the particle size and unfolded the protein, which improved the emulsifying properties of MPs. Excessive HSH speeds (20 500 rpm or higher) caused an aggregation of MP molecules, which was not conducive to improving their emulsifying properties. CONCLUSION: Optimal HSH speed was achieved at 14 500 rpm to modify MPs' emulsifying and structural properties under low-fatconditions. © 2019 Society of Chemical Industry.


Assuntos
Gorduras/análise , Manipulação de Alimentos/métodos , Proteínas Musculares/química , Animais , Galinhas , Emulsões/química , Emulsões/isolamento & purificação , Manipulação de Alimentos/instrumentação , Carne/análise , Proteínas Musculares/isolamento & purificação , Tamanho da Partícula , Pressão , Dobramento de Proteína
11.
J Food Sci ; 84(8): 2199-2208, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31313316

RESUMO

Bioactive anthocyanins from aqueous extracts of muscadine grape pomace were concentrated using osmotic distillation (OD) and direct contact membrane distillation (DCMD) using polypropylene (PP) and poly(ethylene chlorotrifluoroethylene) (ECTFE) membranes. The driving force for OD is created by using a high concentration brine solution while the driving force for DCMD is generated by elevating the feed temperature relative to the permeate temperature. The brine concentration used was 4 M. The lowest fluxes were obtained for OD. Given the temperature sensitive nature of anthocyanins, the maximum temperature difference during DCMD was limited to 30 °C. The feed temperature was 40 °C and the permeate at 10 °C. Consequently, the maximum flux during DCMD was also limited. A combination of OD and DCMD was found to give the highest fluxes. High-performance liquid chromatography (HPLC) and HPLC-electrospray mass spectrometry were used to identify and quantify anthocyanins, cyanidin-3,5-O-diglucoside, delphinidin-3,5-O-diglucoside, petunidin-3,5-O-diglucoside, peonidin-3,5-O-diglucoside, and malvidin-3,5-O-diglucoside. The results obtained here suggest that, though water fluxes for DI water feed streams for PP and ECTFE membrane were similar, the fluxes obtained for the two membranes when using muscadine pomace extracts were different. Concentration factors of close to 3 was obtained for anthocyanins. Membranes also showed slightly different performance in the concentration process. Membrane surfaces were analyzed using scanning electron microscopy and Fourier-transformed infrared spectroscopy. The results suggest that adsorption of these anthocyanins on the membrane surface lead to performance differences. In an actual operation, selection of an appropriate membrane and regeneration of the membrane will be important for optimized performance. PRACTICAL APPLICATIONS: Anthocyanins are valuable therapeutic compounds, which are found in the solid residue left following fruit juice pressing. However, recovery and concentration of these therapeutic compounds remains challenging due to their stability. Here, a novel membrane-based unit operation has been investigated in order to concentrate the anthocyanins that have been extracted into aqueous solutions. The unit operation investigated here use mild processing conditions. Insights into the factors that need to be considered when optimizing of the unit operation for commercialization are discussed.


Assuntos
Antocianinas/isolamento & purificação , Destilação/métodos , Manipulação de Alimentos/métodos , Extratos Vegetais/isolamento & purificação , Vitis/química , Resíduos/análise , Adsorção , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Destilação/instrumentação , Manipulação de Alimentos/instrumentação , Sucos de Frutas e Vegetais/análise , Espectrometria de Massas , Osmose , Extratos Vegetais/análise , Temperatura Ambiente
12.
J Food Sci ; 84(8): 2242-2249, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31329282

RESUMO

The effect of dynamic high-pressure treatment, also named microfluidization, on the surface properties of thermal pea albumin aggregates (AA) and their foaming ability was investigated at pH 3, 5, and 7. The solubility of albumin particles was not affected by the increase in microfluidization pressure from 70 to 130 MPa. Particle charge depended only on the pH, whereas protein surface hydrophobicity was stable at pH 5, decreased at pH 3, but increased at pH 7 after microfluidization treatment and with the applied pressure. Surface tension of AA measured at air/water interface was favorably affected by the microfluidization treatment at each pH preferentially due to size reduction and increased flexibility of protein particles. The foaming capacity and stability of AA depended on the pH conditions and the microfluidization treatment. The high-pressure treatment had little influence in foaming properties at acidic pHs, probably related to a more compact form of AA at these pHs. At neutral pH, the foaming properties of pea AA were strongly influenced by their surface properties and size associated with significant modifications in AA structure with microfluidization. Changes in albumin aggregate characteristics with pH and microfluidization pressure are also expected to modulate other techno-functional properties, such as emulsifying property. PRACTICAL APPLICATION: Albumins are known for their interesting nutritional values because they are rich in essential amino acids. This fraction is not currently marketed as a protein isolate for human consumption, but can be considered as a potential new vegetable protein ingredient. This document demonstrated that heat treatment or dynamic high-pressure technology can control the foaming properties of this protein for possible use in expanded foods.


Assuntos
Albuminas/química , Manipulação de Alimentos/métodos , Ervilhas/química , Proteínas de Vegetais Comestíveis/química , Emulsões/química , Manipulação de Alimentos/instrumentação , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Pressão , Agregados Proteicos , Solubilidade , Propriedades de Superfície , Tensão Superficial
13.
J Food Sci ; 84(8): 2222-2227, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31339565

RESUMO

The conventional prolonged parboiling process results in high operation cost and grain darkening, which may limit consumption. Moreover, residue generation by rice industries is another challenge. The objective of this study was to evaluate the use of microwave irradiation during soaking and gelatinization stages of parboiling rice. Processing time, colorimetric profile, broken and nongelatinized grains, sucrose and glucose content, free 5-hydroxymethyl-2-furfural, and residual phosphorus were evaluated. As the soaking and gelatinization times during microwave treatments increased, the colorimetric parameters increased; however, the values were lower than those with the conventional process. Regardless of soaking time, a decrease in broken and nongelatinized grains was obtained by using the lowest steaming time (5 min). Additionally, lower residual phosphorus content was found in soaking water (10 and 20 min) when using microwave irradiation. Under favorable conditions, a reduction in the levels of broken and nongelatinized grains, residual phosphorus, and color changes was observed, indicating that microwave irradiation may be more beneficial than conventional parboiling. PRACTICAL APPLICATION: Parboiling requires a high volume of water and soaking time, which leads to high costs, underutilization of infrastructures, and high residue in the water after processing. The rapid parboiling process involves the use of microwaves during the soaking and gelatinization stages. The main advantages of the microwave parboiling process include reduced processing time, ranging from 83% to 95%, higher gelatinization, greater yield, reduced darkening, and reduced residual phosphorus in the effluents by 60%. This report can aid industries in streamlining their processes, thereby providing a high-quality, lower cost, and environmentally safe product.


Assuntos
Manipulação de Alimentos/métodos , Oryza/química , Oryza/efeitos da radiação , Fósforo/análise , Águas Residuárias/análise , Culinária , Temperatura Alta , Micro-Ondas , Sementes/química , Sementes/efeitos da radiação
14.
J Food Sci ; 84(8): 2181-2189, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31355452

RESUMO

This study was conducted to optimize a process of cold plasma pretreatment for hot-air drying on corn kernels. Effects of plasma pretreatment time (30, 40, 50 s), plasma pretreatment power (300, 400, 500 W) and drying temperature (37.5, 45, 52.5 °C) on drying time and drying rate during this process were investigated. Polynomial equations were established through a three-factor and three-level Box-Behnken design and used to evaluate the optimal operational conditions for the drying process. The optimal pretreatment conditions were drying temperature at 52.5 °C, plasma pretreatment time of 50 s and plasma pretreatment power of 500 W, and the corresponding drying rate and drying time were 3.6163 (g/g h-1 ) and 1.29 hr, respectively. The AFM images showed that cold plasma pretreatment can change the topography of the treated surface with some micro-holes, which explain how the plasma pretreatment can improve the drying process. PRACTICAL APPLICATION: Cold plasma pretreatment can improve the efficiency of corn kernels drying. Furthermore, it has potential application for reducing energy consumption in drying. Cold plasma pretreatment could be potentially applied in grain drying.


Assuntos
Dessecação/métodos , Manipulação de Alimentos/métodos , Gases em Plasma/farmacologia , Sementes/química , Zea mays/efeitos dos fármacos , Sementes/efeitos dos fármacos , Temperatura Ambiente , Zea mays/química
15.
Toxicol Lett ; 314: 75-81, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31284020

RESUMO

Aflatoxin is a fungal secondary metabolite with high toxicity that is capable of contaminating various types of food crops. It has been identified as a Group 1 human carcinogen by the International Agency for Research on Cancer. Chronic aflatoxin exposure has caused worldwide concern as a matter of public food safety. Peanuts and peanut products are the major sources of aflatoxin exposure. Therefore, some reduction interventions have been developed to minimize contamination throughout the peanut production chain. The purpose of this study is to estimate the efficacy of interventions in reducing the health impact of hepatocellular carcinoma caused by aflatoxin contamination in peanuts. The estimated total Disability-Adjusted Life Years (DALYs) were calculated using FDA-iRISK software. Six aflatoxin reduction strategies were evaluated, including good agricultural practice (GAP), biocontrol, Purdue Improved Crop Storage packaging, basic processing, ozonolysis, and ultraviolet irradiation. The results indicated that basic processing could prevent huge public health loss of 4,079.7-21,833 total DALYs per year. In addition, GAP and biocontrol were both found to be effective strategies in the farm field. Meanwhile, the other three interventions had limited effectiveness in reducing total DALYs. In conclusion, this study could help farmers, processing plants, and government policy makers to alleviate aflatoxin contamination issues in the peanut production chain.


Assuntos
Aflatoxinas/efeitos adversos , Arachis/microbiologia , Carcinoma Hepatocelular/prevenção & controle , Produtos Agrícolas/microbiologia , Exposição Dietética/efeitos adversos , Exposição Dietética/prevenção & controle , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/prevenção & controle , Neoplasias Hepáticas/prevenção & controle , Anos de Vida Ajustados por Qualidade de Vida , Agentes de Controle Biológico , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Efeitos Psicossociais da Doença , Avaliação da Deficiência , Manipulação de Alimentos/métodos , Armazenamento de Alimentos , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Ozônio/química , Fatores de Proteção , Medição de Risco , Fatores de Risco , Fatores de Tempo , Raios Ultravioleta
16.
Sci Total Environ ; 691: 252-262, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31323571

RESUMO

Various antimicrobial interventions are applied sequentially in the beef processing industry to reduce microbial load on beef products by using intensive inputs (e.g., chemicals, energy), high strength wastewater, and potentially result in meat discoloration. This study serves as the first analysis to jointly evaluate environmental and economic assessment with its microbial load reduction of proposed antimicrobial systems in the U.S. beef processing industry to identify relatively sustainable systems that minimize environmental and economic impacts while providing microbial safe meat. Specifically, forty potential sequential antimicrobial systems were proposed and evaluated from three perspectives: microbial load reduction, environmental, and economic impacts, by meta-analysis, life cycle assessment, and operational cost analysis orderly. The results show that the antimicrobial systems applying steam pasteurization during the main intervention offer high microbial load reduction (>4.2 log CFU/cm2 reduction from a hypothetical initial contamination at 5.0 log CFU/cm2). Human health impact (31.0 to 65.6%) and ecosystem toxicity (3.6 to 12.5%), eutrophication (11.9 to 15.5%) and global warming (6.4 to 22.2%) are the main contributors to the overall environmental single score among the forty antimicrobial systems. Antimicrobial chemicals (up to 82.8%), wastewater treatment (up to 12.7%), and natural gas (up to 10.7%) are the three major drivers of operational cost for sanitizing 1000 kg hot standard carcass weight (HSCW). Devalued (discolored) meat due to contact with heat from steam pasteurization or hot water wash has a considerable increase in economic ($4.5/1000 HSCW) and environmental (especially at farm stage) impacts. Certain antimicrobial systems (e.g., water wash followed by steam pasteurization) were found to be more promising with satisfactory effectiveness, better environmental and cost performance under uncertainty (1000 Monte Carlo simulations). Results from this study can guide the U.S. beef processing industry to advance sustainability while protecting human health from foodborne illness.


Assuntos
Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Carne Vermelha , Matadouros , Animais , Anti-Infecciosos , Bovinos , Qualidade de Produtos para o Consumidor , Manipulação de Alimentos/estatística & dados numéricos , Doenças Transmitidas por Alimentos , Humanos
17.
J Dairy Sci ; 102(8): 6928-6942, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31202661

RESUMO

Innovative processing technologies, such as ultrasonication, can change the properties of milk, allowing for the improvement or development of dairy foods. Yet taking bench-scale equipment to pilot plant scale has been challenging. Raw milk, standardized to 3% fat and warmed to inlet temperatures of 42 or 54°C, was exposed to continuous, high-intensity, low-frequency ultrasonication (16/20 kHz, 1.36 kW/pass) at flow rates of 0.15, 0.30, and 0.45 L/min that resulted in resident times within the reaction cell of 6, 3, and 2 min per pass, respectively. Multiple passes (3, 5, and 7, respectively) were required to obtain a total exposure time of 14 to 18 min. Evaluation of fat droplet sizes, enzyme coagulation properties, and microstructure of milk and milk gels, as well as determining compositional and lipid properties, were conducted to determine the potential of the ultrasound system to effectively modify milk. Laser scanning particle sizing and confocal microscopy showed that the largest droplets (2.26 ± 0.13 µm) found in raw milk were selectively reduced in size with a concomitant increase in the number of submicron droplets (0.37 ± 0.06 µm), which occurred sooner when exposed to shorter bursts of ultrasonication (0.45 L/min flow rates) and at an inlet temperature of 54°C. Ultrasound processing with milk entering at 42°C resulted in faster gelling times and firmer curds at 30 min; however, extended processing at inlet temperature of 54°C reduced curd firmness and lengthened coagulation time. This showed that ultrasonication altered protein-protein and protein-lipid interactions, thus the strength of the enzyme-set curds. Scanning electron microscopy revealed a denser curd matrix with less continuous and more irregular shaped and clustered strands, whereas transmission electron microscopy showed submicron lipid droplets embedded within the protein strands of the curd matrix. Processing at inlet temperature of 54°C with flow rates of 0.30 and 0.45 L/min also reduced the total aerobic bacterial count by more than 1 log cfu/mL, and the number of psychrophiles below the limit of detection (10 cfu/mL) for this study. Ultrasonication exposures of 14 to 18 min had minimal effect on the milk composition, fatty acid profiles, and lipid heat capacity and enthalpy. The findings show that this continuous ultrasound system, which is conducive to commercial scale-up, modifies the physical and functional properties of milk under the parameters used in this study and has potential use in dairy processing.


Assuntos
Bovinos/metabolismo , Glicoproteínas/ultraestrutura , Leite/química , Animais , Carga Bacteriana/veterinária , Indústria de Laticínios , Feminino , Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Glicolipídeos/química , Glicoproteínas/química , Temperatura Alta , Lipídeos/química , Leite/enzimologia , Leite/microbiologia , Sonicação/veterinária , Termodinâmica
18.
Food Chem ; 297: 124946, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253319

RESUMO

This second paper provides chemical insight of the different phenomena occurring in bread during storage with and without anti-staling enzymes by using near infrared spectroscopy and chemometrics. The target, thus, is three-fold: (1) To monitor the staling process in the top, middle and bottom parts of the white bread loaf by near infrared spectroscopy and to extract chemical information of the different chemical mechanisms occurring in the staling process; (2) to assess the correlation between the near infrared spectroscopy and spatial texture profile analysis in terms of hardness, and (3) to demonstrate the anti-staling effect of the enzymes by showing a collapse of the correlation between near infrared (NIR) spectra and hardness as measured by texture analysis. It is found that NIR spectroscopy in combination with chemometrics (Partial Least Squares Regression) can predict the hardness development of the control bread.


Assuntos
Pão/análise , Manipulação de Alimentos/métodos , Glicosídeo Hidrolases/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Triticum/metabolismo , Dureza , Análise dos Mínimos Quadrados , Análise de Componente Principal , Triticum/química
19.
J Sci Food Agric ; 99(12): 5594-5600, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31206180

RESUMO

BACKGROUND: Innovative technologies are experimentally applied to the virgin olive oil extraction process in order to make it continuous and more efficient. Most of the efforts aim at overcoming the limitations of the traditional malaxation step, which, however, is essential for the development of virgin olive oil sensory notes. RESULTS: Compared to the traditional process, innovative technologies based on the heat exchanger led generally to a decrement in volatile lipoxygenase (LOX) alcohols linked to alcohol dehydrogenase activity and, conversely, to a slightly increase in volatile LOX esters. Aldehydes from the same pathway were not significantly affected. However, an industrial combined plant constructed from a heat exchanger, low-frequency ultrasound device and microwave apparatus determined the highest 'fruity' intensity perceived by panellists, in accordance with the highest value of total volatiles, with values significantly higher than heat exchanger alone, which, instead, had the lowest levels of hexanal and LOX alcohols. The pungent taste showed the same trend observed for 'fruity' intensity, whereas bitter taste did not show significant differences among trials. CONCLUSION: The introduction of ultrasound, coupled with heat exchanger and microwave, seemed not to modify the behaviour of enzymes of the LOX pathway, and the obtained virgin olive oils showed volatiles and organoleptic characteristics not significantly different from those obtained by the traditional olive oil extraction process. These findings provided the first insights into the effect of the combination of innovative technologies in the olive oil extraction process on virgin olive oil volatiles and sensory characteristics. © 2019 Society of Chemical Industry.


Assuntos
Manipulação de Alimentos/métodos , Olea/química , Azeite de Oliva/isolamento & purificação , Compostos Orgânicos Voláteis/isolamento & purificação , Frutas/química , Humanos , Azeite de Oliva/análise , Paladar , Compostos Orgânicos Voláteis/química
20.
Food Chem ; 297: 124957, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253331

RESUMO

Interactions among food components during food processing play important role in starch digestibility. The objective of this study was to investigate the effects of heat moisture treatment on the structural, physicochemical, and digestibility properties of starch-soybean peptide complexes. Corn and potato starch mixed with different amounts of soybean peptide were subjected to heat moisture treatment. The addition of soybean peptide increased pasting temperature, while decreased peak viscosity and swelling power in both starch samples under heat moisture treatment. Thermal analysis showed that soybean peptide retarded starch gelatinization, and heat moisture treatment contributed to a more stable crystalline structure. Lower RDS contents and higher RS contents were associated with higher soybean peptide amounts. Potato starch was more sensitive to heat moisture treatment than corn starch. The results will enrich the interaction theory between starch and protein, and will be important for the development of carbohydrate-restricted diet and protein-based functional foods.


Assuntos
Proteínas de Soja/química , Proteínas de Soja/farmacocinética , Amido/química , Amido/farmacocinética , Digestão , Manipulação de Alimentos/métodos , Temperatura Alta , Peptídeos/química , Peptídeos/farmacocinética , Solanum tuberosum/química , Viscosidade , Zea mays/química
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