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1.
Foods ; 12(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685113

RESUMO

BACKGROUND: Sour cassava starch is used as an alternative to wheat flour in breadmaking. However, its nutritional and technological properties are limited. To remedy this, the use of legumes has proved to be very successful. Thus, the present study aimed to determine the optimal condition for the production of bread made from sour cassava starch, peanut, cowpea and soybean flour. METHODS: The I-optimal design was employed to obtain an optimal proportion of the mixture with the variables sour cassava starch, cowpea, soy and peanut flour. The responses evaluated were overall acceptability, specific volume and protein content. RESULTS: It resulted that the incorporation of sour cassava starch positively influenced the volume but negatively influenced the protein content and overall acceptability. While the addition of legumes increased protein content and overall consumer acceptability, the specific volume was reduced. The optimal proportions of sour cassava starch, cowpea, soybean and peanut flour were 64.11%, 18.92%, 0% and 16.96%, respectively. Under this condition, it led to a desirability of 1, specific volume of 1.35, overall acceptability of 6.13, protein content of 9.72%, carbohydrate content of 67.89%, fat content of 9.39%, fiber content of 2.10% and ash content of 1.04%. CONCLUSIONS: The findings suggest that cowpea and peanut can be used for the improvement of the technological, nutritional and sensory properties of sour cassava starch bread and thus increase its consumption and application in the food processing industry.

2.
J Food Sci Technol ; 60(4): 1446, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36936120

RESUMO

[This retracts the article DOI: 10.1007/s13197-019-03661-5.].

3.
J Sci Food Agric ; 103(9): 4329-4339, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36799097

RESUMO

BACKGROUND: The consumption of green banana flour (GBF) products has been linked to reduced glycemic index (GI) and low risk of type 2 diabetes and obesity. The purpose of this study was to investigate the effect of micronization (high-intensity infrared heating method) on the molecular, microstructure and in vitro starch digestibility of five GBF cultivars grown in South Africa. The GBF was micronized at three surface temperatures (90, 120 and 150 °C for 30 min) and the in vitro starch digestibility was determined with Megazyme kits. RESULTS: Micronization at the highest temperature (150 °C) increased the swelling power by 6.00% in all five GBF cultivars when compared to control (unmicronized GBF). Micronization slightly reduced the resistant starch (RS) of the GBF cultivars by up to 8.63%. The FHIA-01 cultivar showed the highest RS (86.50%), whereas Grande Naine - 150 °C cultivar had the lowest RS (76.00%). Both micronized and control GBF exhibited similar X-ray diffraction patterns with all cultivars and at all micronization temperatures. Similarly, the functional properties of the GBF were not altered by micronization when observed with Fourier transform infrared spectroscopy. Scanning electron microscopy showed changes in the surface morphology of starch granules after micronization and these were dependent on temperature. CONCLUSION: Overall, micronization at 120 °C showed the best improvement in functional properties of GBF and this makes it suitable for potential application for the manufacture of instant breakfast products, baked goods and pasta. In addition, the micronized GBF cultivars retained high RS, suggesting potential health benefits for people with diabetes and obesity. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Diabetes Mellitus Tipo 2 , Musa , Humanos , Amido/química , Musa/química , Farinha , Amido Resistente , Obesidade
4.
Front Genet ; 12: 672149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858466

RESUMO

Spore-forming Bacillus species are gaining interest in human health recently, due to their ability to withstand the harsh environment of the gastrointestinal tract. The present study explores probiotic features of Bacillus paranthracis strain MHSD3 through genomic analysis and in vitro probiotic assays. The draft genome of strain MHSD3 contained genes associated with tolerance to gastrointestinal stress and adhesion. Cluster genes responsible for the synthesis of antimicrobial non-ribosomal peptide synthetases, bacteriocins, and linear azole-containing peptides were identified. Additionally, strain MHSD3 was able to survive in an acidic environment, had the tolerance to bile salt, and exhibited the capability to tolerate gastric juices. Moreover, the isolate was found to possess strong cell surface traits such as high auto-aggregation and hydrophobicity indices of 79 and 54%, respectively. Gas chromatography-mass spectrometry analysis showed that the strain produced secondary metabolites such as amino acids, phenolic compounds, and organic acid, known to exert health-promoting properties, including the improvement of gastrointestinal tract health.

5.
Foods ; 10(12)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34945646

RESUMO

Sorghum, cowpea, and cassava are underutilised gluten-free sources of flour that have the potential to be used in bread products in sub-Saharan Africa. Excessive wheat imports affect the economies of countries in sub-Saharan Africa, driving the search for wheat flour alternatives. To extend the use of sorghum, cowpea, and cassava flours toward bread production, it is vital that the sensory properties of these flours are better understood. A trained sensory panel evaluated and described the sensory properties of flatbread models prepared from red non-tannin sorghum, fractions (whole and dehulled) of two cowpea varieties, cassava starch, and designated flour composites. The composites were prepared using cassava starch and sorghum flour at 0%, 35%, and 70%, respectively, with 30% cowpea flour. The addition of sorghum intensified sorghum aroma in flatbread, while cowpea flours contributed a beany flavour. Flatbreads from cassava-cowpea composites had a chewier and rubberier mouthfeel, an intense fermented aroma and flavour, and a sour aftertaste compared to single flours, but were most similar to the wheat flatbread, with a residual beany flavour. Information from this study can guide food product developers toward developing new bread products from sorghum, cassava, and cowpea composite flours, thereby moving Africa towards a more sustainable food system. Further research on the effects of the sensory characteristics on consumer liking of the flatbreads is needed.

6.
Foods ; 10(12)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34945445

RESUMO

This study aimed to investigate the proximate composition, mineral content, functional properties, molecular structure, in vitro starch digestibility, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (DPPH, FRAP) of green banana flour (GBF) cultivars grown in South Africa. With proximate composition, Finger Rose and Pisang Awak had the highest protein (4.33 g/100 g) and fat (0.85 g/100 g) content, respectively. The highest ash content (3.50 g/100 g) occurred with both Grand Naine and FHIA-01 cultivars. Potassium and copper were the most abundant and least minerals, respectively. Pisang Awak cultivar had the highest water absorption capacity (67.11%), while Du Roi had the highest swelling power (0.83 g/g) at 90 °C. Scanning electron microscopy (SEM) images revealed that starch granules from all GBF cultivars were irregular in shape and they had dense surfaces with debris. All the GBF cultivars had similar diffraction patterns with prominent peaks from 15°-24° diffraction angles. The resistant starch (RS) and amylose content of the FHIA-01 cultivar indicates that the GBF has the potential to lower risks of type 2 diabetes and obesity. The highest TPC, TFC and antioxidant activity occurred with the Grande Naine cultivar. Based on their functional characteristics, the Grand Naine and FHIA-01 GBF cultivars could potentially be used as raw materials for bakery products as well as for the fortification of snacks.

7.
Molecules ; 26(20)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34684718

RESUMO

The infrared heating of preconditioned cowpea improves its utilization and potential application in food systems. This study investigated the effect of optimizing preconditioning and infrared heating parameters of temperature and time on cooking characteristics of precooked cowpeas using response surface methodology (RSM). The moisture level (32-57%), infrared heating temperature (114-185 °C), and time of processing the seeds (2-18 min) were optimized using a randomized central composite design to achieve optimal characteristics for bulk density and water absorption. A second-order polynomial regression model was fitted to the obtained data, and the fitted model was used to compute the multi-response optimum processing conditions, which were the moisture of 45%, the heating temperature of 185 °C, and time of 5 min. Precooked cowpea seeds from optimized conditions had a 19% increase in pectin solubility. The total phenolic and total flavonoid contents were significantly reduced through complexation of the seeds' phenolic compounds with other macromolecules but nonetheless exhibited antioxidant properties capable of scavenging free radicals. There was also a significant reduction in phytate and oxalates by 24% and 42%, respectively, which was due to the heat causing the inactivation of these antinutrients. The obtained optimized conditions are adequate in the production of precooked cowpea seeds with improved quality.


Assuntos
Culinária/métodos , Calefação/métodos , Vigna/metabolismo , Antioxidantes/análise , Flavonoides/análise , Manipulação de Alimentos/métodos , Temperatura Alta , Raios Infravermelhos , Fenóis/análise , Sementes/química , Solubilidade , Temperatura , Água
8.
Molecules ; 26(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500636

RESUMO

The African pumpkin (Momordica balsamina) contains bioactive phenolic compounds that may assist in reducing oxidative stress in the human body. The leaves are mainly consumed after boiling in water for a specific time; this hydrothermal process and conditions of the gastrointestinal tract may affect the presence and bioactivity of phenolics either positively or negatively. In this study, the effects of hydrothermal processing (boiling) and in vitro simulated human digestion on the phenolic composition, bioaccessibility and bioactivity in African pumpkin were investigated in comparison with those of spinach (Spinacia oleracea). A high-resolution ultra-performance liquid chromatography, coupled with diode array detection, quadrupole time-of-flight and mass spectrometer (UPLC-DAD-QTOF-MS) was used to profile phenolic metabolites. Metabolites such as 3-caffeoylquinic acid, 5-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid were highly concentrated in the boiled vegetable extracts compared to the raw undigested and all digested samples. The majority of African pumpkin and spinach extracts (non-digested and digested) protected Deoxyribonucleic acid (DNA), (mouse fibroblast) L929 and human epithelial colorectal adenocarcinoma (Caco-2) cells from 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH)-induced oxidative damage. From these results, the consumption of boiled African pumpkin leaves, as well as spinach, could be encouraged, as bioactive metabolites present may reduce oxidative stress in the body.


Assuntos
Cucurbita/química , Digestão/efeitos dos fármacos , Momordica/química , Fenóis/química , Fenóis/farmacologia , Folhas de Planta/química , Animais , Antioxidantes/química , Células CACO-2 , Linhagem Celular Tumoral , Flavonoides/química , Humanos , Camundongos , Oxirredução/efeitos dos fármacos , Extratos Vegetais/química , Polifenóis/química , Ácido Quínico/análogos & derivados , Ácido Quínico/química , Spinacia oleracea/química , Verduras/química
9.
Int J Biol Macromol ; 184: 678-688, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34174303

RESUMO

Native starches are not suitable for industrial use and must be modified for improved functionality. In this study, the effect of moisture preconditioning and infrared heating time on physicochemical properties of cowpea starch was investigated using a two-factor central composite rotatable design. Factors (moisture levels:10-40 g/100 g starch and infrared heating time:10-60 min) with their corresponding α mid-point values resulted in 13 experimental runs. Selected functional and pasting properties were determined as response variables. Starch samples produced under optimized conditions were compared with corn starch and their physicochemical properties determined. Except for pasting temperature, cowpea starch prepared using the optimal conditions (moisture: 46.21 g/100 g starch, dry basis and heating time of 32.88 min) had higher functional and pasting properties compared with the native cowpea starch. Infrared heating significantly reduced the gelatinization temperatures of cowpea starch but did not significantly change that of the corn starch. The crystallinity and double-helical order structure of moisture conditioned cowpea starch also reduced after modification. Cowpea starch showed a bigger granule size, higher swelling power but lower water absorption capacities and pasting properties compared with the control. The infrared heating process is a novel and promising modification method for improving the swelling properties of starch.


Assuntos
Amido/química , Vigna/química , Água/química , Cristalografia por Raios X , Temperatura Alta , Estrutura Molecular , Solubilidade , Viscosidade , Difração de Raios X
10.
Data Brief ; 36: 107102, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34026987

RESUMO

This data article reports the untargeted metabolite profile of whole grain sorghum (Sorghum bicolor L.) and fermented ting samples obtained using two strains of Lactobacillus fermentum. The sorghum grains were obtained from Agricol Johannesburg (South Africa) and fermentation was done at 34 °C for 24 h. Controlled fermentation with two Lactobacillus fermentum strains (L. fermentum FUA 3165 and L. fermentum FUA 3321), was done using the strains singly and in combination. The samples obtained thereafter were freeze-dried and acetonitrile/methanol/water (v/v/v) were used as extraction solvent, before analyses on a gas chromatography high resolution time of flight mass spectrometry (GC-HRTOF-MS) system. Data obtained showed the presence of different compounds, classified into metabolite groups such as acids, alcohols, benzenes, furan, esters, hydrocarbons, terpenes, phytosterols, etc., with their retention time, molecular formula, observed mass and average peak areas reported herein. These data can be used for finding biomarkers for sorghum and their derived fermented products.

11.
Heliyon ; 7(4): e06666, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33889778

RESUMO

Metabolite profile provides an overview and avenue for the detection of a vast number of metabolites in food sample at a particular time. Gas chromatography high resolution time-of-flight mass spectrometry (GC-HRTOF-MS) is one of such techniques that can be utilized for profiling known and unknown compounds in a food sample. In this study, the metabolite profiles of Bambara groundnut and dawadawa (unhulled and dehulled) were investigated using GC-HRTOF-MS. The presence of varying groups of metabolites, including aldehydes, sterols, ketones, alcohols, nitrogen-containing compounds, furans, pyridines, acids, vitamins, fatty acids, sulphur-related compounds, esters, terpenes and terpenoids were reported. Bambara groundnut fermented into derived dawadawa products induced either an increase or decrease as well as the formation of some metabolites. The major compounds (with their peak area percentages) identified in Bambara groundnut were furfuryl ether (9.31%), bis (2-(dimethylamino)ethyl) ether (7.95%), 2-monopalmitin (7.88%), hexadecanoic acid, methyl ester (6.98%), 9,12-octadecadienoic acid (Z,Z) and 2-hydroxy-1-(hydroxymethyl)ethyl ester (5.82%). For dehulled dawadawa, the significant compounds were palmitic acid, ethyl ester (17.7%), lauric acid, ethyl ester (10.2%), carbonic acid, 2-dimethylaminoethyl 2-methoxyethyl ester (7.3%), 9,12-octadecadienoic acid (Z,Z)-, 2-hydroxy-1-(hydroxymethyl)ethyl ester (5.13%) and maltol (4%), while for undehulled dawadawa, it was indoline, 2-(hydroxydiphenylmethyl) (26.1%), benzoic acid, 4-amino-4-hydroximino-2,2,6,6-tetramethyl-1-piperidinyl ester (8.2%), 2-undecen-4-ol (4.7%), 2-methylbutyl propanoate (4.7%) and ë-tocopherol (4.3%). These observed metabolites reported herein provides an overview of the metabolites in these investigated foods, some of which could be related to nutrition, bioactivity as well as sensory properties. It is important to emphasize that based on some of the metabolites detected, it could be suggested that Bambara groundnut and derived dawadawa might serve as functional foods that are beneficial to health.

12.
Plants (Basel) ; 10(4)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917651

RESUMO

A literature survey revealed that several wild indigenous Southern African fruits had previously not been evaluated for their proximate and amino acid composition, as well as the total energy value (caloric value). Fourteen species including Carissa macrocarpa, Carpobrotus edulis, Dovyalis caffra, Halleria lucida, Manilkara mochisia, Pappea capensis, Phoenix reclinata, and Syzygium guineense were analyzed in this study. The nutritional values for several species such as C. edulis, H. lucida, P. reclinata, and M. mochisia are being reported here for the first time. The following fruits had the highest proximate values: C. macrocarpa (ash at 20.42 mg/100 g), S. guineense (fat at 7.75 mg/100 g), P. reclinata (fiber at 29.89 mg/100 g), and H. lucida (protein at 6.98 mg/100 g and carbohydrates at 36.98 mg/100 g). Essential amino acids such as histidine, isoleucine, lysine, methionine, phenylalanine, tryptophan, and valine were reported in all studied indigenous fruits. The high protein content in H. lucida was exhibited by the highest amino acid quantities for histidine. However, the fruits are a poor source of proteins since the content is lower than the recommended daily intake. The jacket-plum (Pappea capensis), on the other hand, meets and exceeds the required daily intake of lysine (0.0003 g/100 g or 13 mg/kg) recommended by the World Health Organization.

13.
Int J Biol Macromol ; 176: 87-95, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33577814

RESUMO

Native starches are unsuitable for most industrial applications. Therefore, they are modified to improve their application in the industry. Starch may be modified using enzymatic, genetic, chemical, and physical methods. Due to the demand for safe foods by consumers, researchers are focusing on the use of cheap, safe and environmentally friendly methods such as the use of physical means for starch modification. Microwave heating of starch is a promising physical method for starch modification due to its advantages such as homogeneous operation throughout the whole sample volume, shorter processing time, greater penetration depth and better product quality. More recently, the use of synergistic methods for starch modification is being encouraged because they confer better functionality on starch than single methods. This review summarizes the present knowledge on the structure and physicochemical properties of starches from different botanical origins modified using microwave heating alone and in combination with other starch modification methods.


Assuntos
Amido/química , Fenômenos Químicos , Cristalografia por Raios X , Digestão , Tecnologia de Alimentos , Géis/química , Temperatura Alta , Humanos , Micro-Ondas , Amido Resistente , Amido/ultraestrutura
14.
Food Res Int ; 121: 326-335, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31108755

RESUMO

Fermented whole grain (WG) sorghum food products including WG-ting can be obtained from different sample sources and fermentation conditions, leading subsequently to variations in the molecular composition of the products. There is however, a lack of detailed understanding and description of differential molecular profiles of these food products. Thus, the current study is a nontargeted gas chromatography-mass spectrometry (GC-MS)-based metabolomics approach to descriptively elucidate metabolic profiles of two WG-sorghum types [high tannin (HT) and low tannin (LT)] and their derived WG-ting products obtained via fermentation. Metabolites were extracted with 80% aqueous methanol and analyzed on a gas chromatography high resolution time of flight mass spectrometry (GC-HRTOF-MS) system. Chemometric methods such as principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA) were applied to mine the generated data. Our results showed that tannin contents influenced the composition of the raw sorghum and derived WG-ting samples. Metabolite signatures that differentiated raw HT- and LT-sorghum included cyclic compounds, pesticides, 2,4-di-tert-butylphenol, fatty acid esters, and sugar derivatives. Furthermore, fermentation of the HT- and LT-sorghum into WG-ting led to an increase in the levels of fatty acids, fatty acid esters and some other compounds which are vital from a dietary and health context. Equally observed were reduction of some phenols, cyclic compounds, a pesticide and ketone. Thus, the results demonstrated that the inherent metabolic composition of raw sorghum would lead to differential metabolic changes in the fermented products such as WG-ting, with subsequent dietary and health implications. Fermenting ting with Lactobacillus fermentum FUA 3321 was most desirable as relevant metabolites were observed in both HT- and LT-ting samples. Furthermore, the study highlights the applicability of GC-MS metabolomics in understanding WG-ting fermentation.


Assuntos
Alimentos Fermentados , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lactobacillales , Metabolômica/métodos , Taninos , Alimentos Fermentados/análise , Alimentos Fermentados/microbiologia , Lactobacillales/isolamento & purificação , Lactobacillales/metabolismo , Metaboloma , Sorghum/metabolismo , África do Sul , Taninos/análise , Taninos/metabolismo
15.
Toxins (Basel) ; 11(3)2019 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-30934589

RESUMO

Mycotoxins are fungal secondary metabolites that pose health risks to exposed individuals, requiring necessary measures to reduce them. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), mycotoxins were quantified in whole grain sorghum and ting subsequently derived from two sorghum varieties (high and low tannin). The whole grain (WG) ting samples were obtained by fermenting sorghum with Lactobacillus fermentum strains (FUA 3165 and FUA 3321). Naturally (spontaneously) fermented WG-ting under the same conditions were equally analysed. Among the mycotoxins investigated, fumonisin B1 (FB1), B2 (FB2), B3 (FB3), T-2 toxin (T-2), zearalenone (ZEA), alpha-zearalenol (α-ZOL) and beta-zearalenol (ß-ZOL) were detected in sorghum. Results obtained showed that mycotoxin concentrations significantly (p ≤ 0.05) reduced after fermentation. In particular, L. fermentum FUA 3321 showed the capability to significantly (p ≤ 0.05) reduce all the mycotoxins by 98% for FB1, 84% for T-2 and up to 82% for α-ZOL, compared to raw low tannin sorghum. Fermenting with the L. fermentum strains showed potential to effectively reduce mycotoxin contamination in whole grain ting. Thus, we recommended L. fermentum FUA 3321 in particular to be used as a potential starter culture in sorghum fermentation.


Assuntos
Fermentação , Limosilactobacillus fermentum , Micotoxinas/análise , Sorghum , Grãos Integrais/química , Contaminação de Alimentos/prevenção & controle , África do Sul
16.
J Food Sci Technol ; 56(4): 1669-1682, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30996403

RESUMO

African legumes are an important protein source in the human diet. However, a long and often extended cooking process has been identified as a major challenge in the consumption and utilisation of these legumes. The application of infrared heating as a method of shortening the cooking-time of African legume seeds and flour, by increasing their water absorption rates and pasting viscosity is emphasised in literature. Structural changes caused by infrared heating of moisture-conditioned African legumes include microstructural, molecular and interaction of the biomolecules in the seeds. However, to the best of the authors' our knowledge, no overview on elucidated mechanisms surrounding the microstructural and molecular changes of infrared heated African legumes has been done. The authors' therefore, present current knowledge of these mechanisms including certain highlighted factors such as seed sizes, moisture, surface temperature and time, affecting the efficacy of the application of infrared heating to African legumes. In conclusion, infrared heating is a promising technology that provides a potential solution to the consumption and utilisation challenges of African legumes and flour from these legumes, to enhance their consumption in the food industry.

17.
Food Sci Nutr ; 6(8): 2028-2035, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30510704

RESUMO

The objective of this study was to investigate the volatile flavor compounds of nkui, a Cameroonian food, using solid phase microextraction (SPME) and a two-dimensional gas chromatography time of flight mass spectrometry GC×GC-TOF-MS system. Using SPME, volatile compounds were extracted from nkui and analyzed by GC×GC-TOF-MS. The data retrieved revealed the presence of flavor volatiles including acids (20%), alcohols (4%), aldehydes (10%), aromatic compounds (4%), esters (7%), furans (4%), ketones (11%), terpenes and terpernoids (27%). Although the terpene compounds were the most predominant, an ester (linalyl acetate) had the highest percentage of 19%, conferring a sweet, green and citrus flavor. Results obtained from this study suggest that the characteristic flavor of nkui was due to the combination of different volatile flavor compounds, which contributed to its aroma. Considering the medicinal importance of these compounds, their presence positions nkui as a vital food source with health benefits and medicinal properties.

18.
Crit Rev Biotechnol ; 38(1): 1-16, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28462596

RESUMO

The review focuses on some of the high value-end biocommodities, such as fermented beverages, single-cell proteins, single-cell oils, biocolors, flavors, fragrances, polysaccharides, biopesticides, plant growth regulators, bioethanol, biogas and biohydrogen, developed from the microbial processing of fruit and vegetable wastes. Microbial detoxification of fruit and vegetable processing effluents is briefly described. The advances in genetic engineering of microorganisms for enhanced yield of the above-mentioned biocommodities are elucidated with selected examples. The bottleneck in commercialization, integrated approach for improved production, techno-economical feasibility and real-life uses of some of these biocommodities, as well as research gaps and future directions are discussed.


Assuntos
Bactérias , Biodegradação Ambiental , Frutas , Resíduos Industriais , Verduras , Bactérias/genética , Bactérias/metabolismo , Biocombustíveis , Produtos Biológicos , Engenharia Genética
19.
Food Chem ; 232: 210-217, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28490067

RESUMO

The effects of fermentation and malting on the proximate composition, mineral content, amino acids and total phenolic content of pearl millet flour and biscuits were studied. Consumer tests of the biscuits samples were also done using two sets of panelists. The results showed that fermentation and malting improved the crude fiber, crude protein, carbohydrate and energy values of the pearl millet flour. For the biscuit samples, the fermented and malted biscuits had higher moisture, crude protein, crude fiber and energy value with lower fat and ash content as compared to the biscuits obtained from native flour. Fermentation and malting were further observed to increase majority of the essential and non-essential amino acids. Consumer tests among the different set of panelists showed differences in the loading patterns as observed through principal component analysis. In conclusion, this study shows that fermentation and malting improves nutritional, health composition of pearl millet flour as well as the sensorial acceptability of subsequent biscuits.


Assuntos
Farinha , Pennisetum , Proteínas Alimentares , Fermentação , Manipulação de Alimentos , Valor Nutritivo
20.
Bull Environ Contam Toxicol ; 97(5): 728-736, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27647015

RESUMO

A study which probed the occurrence and quantitative variations hepatotoxic microcystin in a Sub Saharan drinking freshwater reservoir was carried out between November 2014 and March 2015. Results reveal the presence of MCYST-YR, MCYST-LR, MCYST-RR, MCYST-LA and MCYST-LF variants either in cells collected directly from bloom or toxic isolates cultured under laboratory conditions. Two minor microcystin congeners (MCYST-(H4)YR) and (D-Asp3, Dha7) MCYST-RR) were identified, but not quantified. Variants dominance were in the order MCYST-LR > MCYST-RR > MCYST-YR > MCYST-LA > MCYST-LF across sampling sites. Maximum and minimum concentrations of quantified MCYSTs congeners were (489.25, 50.95 µg toxin/g DW), (98.92, 9.11 µg toxin/g DW), (140.25, 12.07 µg toxin/g DW), (56.99, 6.20 µg toxin/g DW) and (50.46, 3.65 µg toxin/g DW) for MCYST-LR, MCYST-YR, MCYST-RR, MCYST-LA and MCYST-LF, respectively. Analysis of variance (ANOVA) revealed there was a high significant difference between mean microcystin concentrations across sampling sites (p < 0.05).


Assuntos
Toxinas Bacterianas/análise , Toxinas Marinhas/análise , Microcistinas/análise , África Subsaariana , Toxinas de Cianobactérias , Água Doce/análise
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