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1.
J Sci Food Agric ; 2023 Mar 30.
Article in English | MEDLINE | ID: mdl-36995920

ABSTRACT

BACKGROUND: Boiled yam key quality attributes typical for West African consumers are that it is crumbly, easy to break and has a sweet taste. New yam varieties are being developed but high- or medium-throughput tools to assess the required quality traits and their range of acceptance are limited. This study assessed the acceptance thresholds of these quality attributes and established predictive models for screening yam varieties that meet the required consumer preferences. RESULTS: Overall liking was associated with sweet taste, crumbliness and easiness to break (r-values 0.502, 0.291 and -0.087, respectively). These parameters and selected biophysical parameters highly discriminated the boiled yam varieties. Crumbly texture and easiness to break were well predicted by penetration force and dry matter, whereas sweet taste were well predicted by dry matter and sugar intensity. A high crumbliness and sweet taste are preferred (sensory scores above 6.19 and 6.22 for crumbly and sweet taste, respectively, on a 10 cm unstructured line scale), while a too high easiness to break is disliked (sensory scores ranging from 4.72 to 7.62). Desirable biophysical targets were between 5.1 and 7.1 N for penetration force, dry matter around 39% and sugar intensity below 3.62 g 100 g-1 . Some improved varieties fulfilled the acceptable thresholds, and screening was improved through deviation from the optimum. CONCLUSION: Acceptance thresholds and deviation from optimum for boiled yam assessed through the instrumental measurements are promising tools for yam breeders. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

2.
J Sci Food Agric ; 95(9): 1876-84, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25171784

ABSTRACT

BACKGROUND: Akpan is a traditional ready-to-drink fermented yoghurt-like cereal beverage consumed in urban and rural areas in Benin. With the aim of adapting the product to new local and export markets, this work maps African and European consumer preferences for different types of Akpan. RESULTS: A sensory profile of Akpan was created and consumer tests were conducted with 103 consumers of African origin and 74 consumers of European origin. Consumer acceptance was significantly correlated with fermented odour (r = -0.94) and milky taste (r = 0.92-0.97) attributes. Cluster analysis revealed different behaviour by African and European consumers with respect to acceptability of Akpan; European consumers did not like the sour taste and African consumers liked an intense sweet milky taste. CONCLUSION: This study provides information on how Akpan, and other fermented yoghurt-type cereal products, could be adapted to African and European consumer preferences.


Subject(s)
Beverages/analysis , Consumer Behavior , Diet , Edible Grain/chemistry , Fast Foods/analysis , Food Preferences , Benin , Beverages/microbiology , Black People , Cluster Analysis , Diet/ethnology , Edible Grain/microbiology , Fast Foods/microbiology , Female , Fermentation , Food Preferences/ethnology , Humans , Hydrogen-Ion Concentration , Male , Odorants , Principal Component Analysis , Sensation , Sorghum/chemistry , Sorghum/microbiology , Taste , White People , Yogurt/analysis , Yogurt/microbiology , Zea mays/chemistry , Zea mays/microbiology
3.
J Food Sci Technol ; 52(3): 1570-7, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25745226

ABSTRACT

In West Africa, landraces or local varieties of fonio are processed into many products by women using small processing units and marketed locally as well as exported to Europe and the United States. The objective of this study was to evaluate the effect of processing methods, namely parboiling, precooking and roasting on the physico-chemical and functional properties of two mainly preferred fonio landraces (Iporhouwan and Namba) by consumers. Results showed that the physico-chemical characteristics and most functional properties were significantly (P < 0.0001) affected by the processing methods. The lowest brightness (L*) values were obtained for parboiled fonio for the two landraces. However, parboiled fonio presented the best biochemical composition as compared to the dehusked, milled, precooked and roasted fonio samples. The protein contents of parboiled fonio samples were 6.06 % and 7.24 % for Iporhouwan and Namba landraces respectively. The values of peak viscosity, trough viscosity, breakdown, final viscosity and setback, were significantly higher for dehusked and milled fonio than for precooked, parboiled and roasted fonio with respect to both landraces. The milled fonio showed highest peak viscosity (2,668.5 cP) which was similar for the both tested landraces.

4.
Ecol Food Nutr ; 53(4): 390-409, 2014.
Article in English | MEDLINE | ID: mdl-24884554

ABSTRACT

Fonio is a traditional cereal cultivated in many West African countries, where farmers are often the guardians of a rich diversity of landraces or traditional varieties. An investigation conducted in northwest of Benin on indigenous knowledge about fonio landraces and fonio-based traditional foods allowed us to inventory 35 landraces identified by the farmers. Ipormoa, Namba, Icantoni or Kopognakè or Icantoga and Iporhouwan landraces were good to cook paste and couscous and easy to dehusk. Besides, Ipormoa and Iporhouwan landraces had interesting agronomic characteristics. Paste, porridge, and couscous were the main fonio-based foods consumed by farmers in northwest of Benin.


Subject(s)
Crops, Agricultural/chemistry , Edible Grain/chemistry , Agriculture , Benin , Crops, Agricultural/classification , Databases, Factual , Edible Grain/classification , Food , Humans , Surveys and Questionnaires
5.
J Nutr ; 143(9): 1376-82, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23884388

ABSTRACT

Iron biofortification of pearl millet (Pennisetum glaucum) is a promising approach to combat iron deficiency (ID) in the millet-consuming communities of developing countries. To evaluate the potential of iron-biofortified millet to provide additional bioavailable iron compared with regular millet and post-harvest iron-fortified millet, an iron absorption study was conducted in 20 Beninese women with marginal iron status. Composite test meals consisting of millet paste based on regular-iron, iron-biofortified, or post-harvest iron-fortified pearl millet flour accompanied by a leafy vegetable sauce or an okra sauce were fed as multiple meals for 5 d. Iron absorption was measured as erythrocyte incorporation of stable iron isotopes. Fractional iron absorption from test meals based on regular-iron millet (7.5%) did not differ from iron-biofortified millet meals (7.5%; P = 1.0), resulting in a higher quantity of total iron absorbed from the meals based on iron-biofortified millet (1125 vs. 527 µg; P < 0.0001). Fractional iron absorption from post-harvest iron-fortified millet meals (10.4%) was higher than from regular-iron and iron-biofortified millet meals (P < 0.05 and P < 0.01, respectively), resulting in a higher quantity of total iron absorbed from the post-harvest iron-fortified millet meals (1500 µg; P < 0.0001 and P < 0.05, respectively). Results indicate that consumption of iron-biofortified millet would double the amount of iron absorbed and, although fractional absorption of iron from biofortification is less than that from fortification, iron-biofortified millet should be highly effective in combatting ID in millet-consuming populations.


Subject(s)
Anemia, Iron-Deficiency/diet therapy , Food, Fortified/analysis , Iron/administration & dosage , Iron/pharmacokinetics , Pennisetum/chemistry , Absorption , Adult , Benin , Cross-Over Studies , Developing Countries , Female , Flour/analysis , Humans , Iron/analysis , Iron Isotopes/analysis , Iron Isotopes/pharmacokinetics , Young Adult
6.
J Nutr ; 143(8): 1233-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23761652

ABSTRACT

Home fortification with lipid-based nutrient supplements (LNSs) is a promising approach to improve bioavailable iron and energy intake of young children in developing countries. To optimize iron bioavailability from an LNS named complementary food fortificant (CFF), 3 stable isotope studies were conducted in 52 young Beninese children. Test meals consisted of millet porridge mixed with CFF and ascorbic acid (AA). Study 1 compared iron absorption from FeSO4-fortifed meals with meals fortified with a mixture of FeSO4 and NaFeEDTA. Study 2 compared iron absorption from FeSO4-fortifed meals without or with extra AA. Study 3 compared iron absorption from FeSO4-fortified meals with meals containing phytase added prior to consumption, once without or once with extra AA. Iron absorption was measured as erythrocyte incorporation of stable isotopes. In study 1, iron absorption from FeSO4 (8.4%) was higher than that from the mixture of NaFeEDTA and FeSO4 (5.9%; P < 0.05). In study 2, the extra AA increased absorption (11.6%) compared with the standard AA concentration (7.3%; P < 0.001). In study 3, absorption from meals containing phytase without or with extra AA (15.8 and 19.9%, respectively) increased compared with meals without phytase (8.0%; P < 0.001). The addition of extra AA to meals containing phytase increased absorption compared with the test meals containing phytase without extra AA (P < 0.05). These findings suggest that phytase and AA, and especially a combination of the two, but not a mixture of FeSO4 and NaFeEDTA would be useful strategies to increase iron bioavailability from a CFF mixed with cereal porridge.


Subject(s)
6-Phytase/administration & dosage , Ascorbic Acid/administration & dosage , Dietary Supplements , Food, Fortified/analysis , Infant Nutritional Physiological Phenomena , Iron, Dietary/pharmacokinetics , Anthropometry , Biological Availability , C-Reactive Protein/analysis , Child, Preschool , Cross-Over Studies , Developing Countries , Edetic Acid/pharmacology , Edible Grain/chemistry , Female , Ferric Compounds/pharmacology , Ferritins/blood , Ferrous Compounds/analysis , Ferrous Compounds/pharmacology , Hemoglobins/analysis , Humans , Infant , Intestinal Absorption/drug effects , Iron, Dietary/administration & dosage , Male , Panicum/chemistry
7.
Front Plant Sci ; 12: 627808, 2021.
Article in English | MEDLINE | ID: mdl-34220877

ABSTRACT

Quality, shelf life, and yield of a pineapple fruit are the important attributes for the producers and customers in the pineapple value chain of Benin, whereas poor quality, short shelf life, and low yield are the main constraints. We quantified the effects of planting density and K2O:N fertilizer ratio on the pineapple yield, external quality, and perceived shelf life in four on-farm experiments with cv. Sugarloaf in Benin; two experiments were installed in the long rainy season and two in the short rainy season. A split-plot design was used with the planting density as the main factor at three levels: 54,000, 66,600, and 74,000 plants.ha-1. The K2O:N ratio was a subfactor with three levels: K2O:N = 0.35 (farmers' practice), K2O:N = 1, and K2O:N = 2. The results showed that both factors had no effect on the crop development variables (such as the number of functional leaves and D-leaf length) at the moment of flowering induction. The planting density had no effect on the total weight per fruit, infructescence weight, total fruit length, infructescence length, crown length, or the fruit shelf life as perceived by traders. The yield increased from 54.9-69.1 up to 90.1 t.ha-1 with an increase in the planting density. The yield increase was not at the expense of the fruit weight. Increased K2O:N ratio led to a higher fruit weight whereas the fruit length was not affected. The shelf life of fruits produced at a K2O:N ratio of 1 and as perceived by traders was 6 days longer than that of fruits produced at a ratio of 0.35 (farmers' practice). Based on these results, we suggest the fresh pineapple farmers in Benin to use a combination of 66,600 plants.ha-1 with a K-fertilization scheme based on a K2O:N ratio of 1 to meet the expectation of both producers and customers in terms of fruit yield and fruit quality.

8.
Int J Food Sci Technol ; 56(3): 1447-1457, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33776245

ABSTRACT

This study aimed to establish the quality characteristics of raw and boiled yam by involving stakeholders along the food chain using a methodology that includes a state of knowledge review, focus group discussion and individual interviews, participatory processing diagnosis with processors and consumer testing. Predictive characteristics of yam for producing a high- and low-quality boiled yam were related to morphological or physicochemical characteristics: peeled yam discoloration and mucilage content being negatively appreciated while the ease of peeling, viscous state of cooking water and the ease of breaking yam into pieces positively valued. High-quality boiled yam should be white or yellowish, sticky to the fingers, nonfibrous, easy to chew, crumbly/friable, with a sweet taste and a good smell. The overall liking of boiled yam is greatly penalised by a too dark colour, hard to the touch, no sweet taste and no friability while eating.

9.
J Sci Food Agric ; 90(3): 438-44, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20355065

ABSTRACT

BACKGROUND: Three Beninese food condiments (ABS1(24h), IBS2(48h) and SBS3(48h)) were produced by controlled fermentation of African locust beans using inocula of pure cultures of Bacillus subtilis, BS1, BS2 and BS3, respectively. Quantitative and qualitative assessments of the volatile compounds in the condiments produced have been performed using the Likens-Nickerson simultaneous distillation-extraction method and GC-MS analysis, followed by a sensory evaluation in comparison with the spontaneously fermented condiments. RESULTS: A total of 94 volatile compounds have been found including 53 compounds identified in relatively high concentrations and were subdivided into seven main groups with the predominance of four major groups: pyrazines, aldehydes, ketones and alcohols. Compared to the spontaneously fermented condiments, volatile compounds identified in controlled fermented condiments have been found in high number and in concentrations which varied according to the inoculum of B. subtilis used. The condiments produced with starter cultures scored significantly (P < 0.05) higher for odour than the spontaneously fermented condiments. But the overall acceptability (7/10) of the two types of condiments was similar. CONCLUSION: The investigated B. subtilis, BS1, BS2 and BS3 can be considered as potential starter cultures for the fermentation of African locust beans to produce good quality of Beninese food condiments.


Subject(s)
Bacillus subtilis/metabolism , Condiments/analysis , Fabaceae/metabolism , Food Microbiology , Plant Extracts/chemistry , Seeds/metabolism , Volatile Organic Compounds/analysis , Benin , Condiments/microbiology , Distillation , Fabaceae/microbiology , Fermentation , Odorants , Seeds/microbiology
10.
Crit Rev Microbiol ; 35(2): 139-56, 2009.
Article in English | MEDLINE | ID: mdl-19514912

ABSTRACT

Alkaline-fermented food condiments play an important role in the diets of many people in developing and a few developed countries. The rise in pH during production of these foods is due to the ability of the dominant microorganisms, Bacillus spp., to hydrolyze proteins into amino acids and ammonia. Studies have been undertaken which have investigated a number of these products like dawadawa, ugba, bikalga, kinema, natto, and thua-nao. In this review, current knowledge about the principal microbiological activities and biochemical modifications which occur during the processing of the alkaline condiments including nutritional, antimicrobial, and probiotic aspects are discussed. The current use of molecular biology methods in microbiological research has allowed unambiguous and more reliable identification of microorganisms involved in these fermentations generating sufficient knowledge for the selection of potential starter cultures for controlled and better production procedures for alkaline-fermented seeds condiments.


Subject(s)
Bacillus/metabolism , Condiments/microbiology , Seeds/metabolism , Seeds/microbiology , Africa , Asia , Fermentation , Humans , Hydrogen-Ion Concentration , Plant Proteins/metabolism
11.
Food Sci Nutr ; 6(4): 1077-1084, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29983972

ABSTRACT

In Burkina Faso, flamed/grilled chickens are very popular and well known to consumers. The aim of this study was to evaluate the microbiological quality, the antibiotic resistance, and the virulence gene from Escherichia coli isolated from these chickens in Ouagadougou. A total of 102 grilled, flamed, and fumed chickens were collected in Ouagadougou and analyzed, using standard microbiological methods. All E. coli isolates were checked with the antimicrobial test and also typed by 16-plex PCR. The mean of aerobic mesophilic bacteria (AMB) and thermo-tolerant coliforms (TTC) was found respectively between 6.90 ± 0.12 × 107 CFU/g to 2.76 ± 0.44 × 108 CFU/g and 2.4 ± 0.82 × 107 CFU/g to 1.27 ± 0.9 × 108 CFU/g. E. coli strains were found to 27.45%. Forty samples (38.24%) were unacceptable based on the AMB load. Fifty-nine samples (57.85%) were contaminated with TTCs. Low resistance was observed with antibiotics of betalactamin family. Diarrheagenic E. coli strains were detected in 21.43% of all samples. This study showed that flamed/grilled chickens sold in Ouagadougou could pose health risks for the consumers. Need of hygienic practices or system and good manufacturing practices is necessary to improve the hygienic quality of flamed/grilled chickens. Our results highlight the need of control of good hygiene and production practices to contribute to the improvement of the safety of the products and also to avoid antibiotic resistance. Slaughter, scalding, evisceration, plucking, bleeding, washing, rinsing, preserving, grilling, and selling may be the ways of contamination.

12.
J Agric Food Chem ; 54(1): 256-62, 2006 Jan 11.
Article in English | MEDLINE | ID: mdl-16390208

ABSTRACT

Seventy-six farmers' varieties of sorghum from Benin were distinguished by amplified fragment length polymorphism (AFLP) and clustered into 45 distinct genotypes. The genotype clusters were evaluated for their Fe, Zn, and phytate concentrations to assess the impact of genetic and environmental effects on the composition of the grains and to identify farmers' varieties with high potential Fe and Zn availability. The Fe concentration of the grains ranged from 30 to 113 mg/kg with an average of 58 mg/kg. The Zn concentration ranged from 11 to 44 mg/kg with an average of 25 mg/kg. The phytate concentration of the grain ranged from 0.4 to 3.5% with a mean of 1.2%. The grain-Fe and grain-Zn did not show consistent linkage to genetic variation, but varied significantly across field locations, suggesting a predominant environmental impact. The phytate concentration of the grains appeared to be environmentally as well as genetically determined. No varieties provide adequate Zn to meet nutritional requirements of sorghum consumers. The most promising varieties for Fe supply were tokogbessenou, mahi swan, biodahu, saï maï, mare dobi, sakarabokuru, and chabicouma, as they showed a [phytate]/[Fe] ratio of <14, which is the critical value above which Fe availability is strongly impaired. These varieties could therefore be recommended for the preparation of food products such as dibou, in which processing methods have only a slight diminishing effect on phytate levels. Further research is needed to test these varieties for the stability of [phytate]/[Fe] molar ratio across various environmental conditions.


Subject(s)
Environment , Iron/analysis , Phytic Acid/analysis , Sorghum/chemistry , Sorghum/genetics , Zinc/analysis , Benin , Edible Grain/chemistry , Edible Grain/genetics
13.
Am J Clin Nutr ; 102(5): 1238-48, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26468121

ABSTRACT

BACKGROUND: Zinc deficiency and contaminated water are major contributors to diarrhea in developing countries. Food fortification with zinc has not shown clear benefits, possibly because of low zinc absorption from inhibitory food matrices. We used a novel point-of-use water ultrafiltration device configured with glass zinc plates to produce zinc-fortified, potable water. OBJECTIVE: The objective was to determine zinc bioavailability from filtered water and the efficacy of zinc-fortified water in improving zinc status. DESIGN: In a crossover balanced study, we measured fractional zinc absorption (FAZ) from the zinc-fortified water in 18 healthy Swiss adults using zinc stable isotopes and compared it with zinc-fortified maize porridge. We conducted a 20-wk double-blind randomized controlled trial (RCT) in 277 Beninese school children from rural settings who were randomly assigned to receive a daily portion of zinc-fortified filtered water delivering 2.8 mg Zn (Zn+filter), nonfortified filtered water (Filter), or nonfortified nonfiltered water (Pump) from the local improved supply, acting as the control group. The main outcome was plasma zinc concentration (PZn), and the 3 groups were compared by using mixed-effects models. Secondary outcomes were prevalence of zinc deficiency, diarrhea prevalence, and growth. RESULTS: Geometric mean (-SD, +SD) FAZ was 7-fold higher from fortified water (65.9%; 42.2, 102.4) than from fortified maize (9.1%; 6.0, 13.7; P < 0.001). In the RCT, a significant time-by-treatment effect on PZn (P = 0.026) and on zinc deficiency (P = 0.032) was found; PZn in the Zn+filter group was significantly higher than in the Filter (P = 0.006) and Pump (P = 0.025) groups. We detected no effect on diarrhea or growth, but our study did not have the duration and power to detect such effects. CONCLUSIONS: Consumption of filtered water fortified with a low dose of highly bioavailable zinc is an effective intervention in children from rural African settings. Large community-based trials are needed to assess the effectiveness of zinc-fortified filtered water on diarrhea and growth. These trials were registered at clinicaltrials.gov as NCT01636583 and NCT01790321.


Subject(s)
Child Nutritional Physiological Phenomena , Drinking Water/administration & dosage , Food, Fortified , Intestinal Absorption , Rural Health , Zinc/metabolism , Adult , Benin/epidemiology , Child , Cross-Over Studies , Deficiency Diseases/diet therapy , Deficiency Diseases/epidemiology , Deficiency Diseases/metabolism , Deficiency Diseases/physiopathology , Diarrhea/etiology , Diarrhea/physiopathology , Diarrhea/prevention & control , Double-Blind Method , Humans , Longitudinal Studies , Plasma/chemistry , Prevalence , Single-Blind Method , Switzerland , Ultrafiltration , Urine/chemistry , Zinc/administration & dosage , Zinc/deficiency , Zinc/therapeutic use , Zinc Isotopes
14.
Food Sci Nutr ; 3(1): 1-9, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25649142

ABSTRACT

Sensory profile of gowe beverage was established with 10 gowe samples by 22 semitrained panelists. Besides, consumer study was performed on four representative gowe samples with 141 African ordinary consumers using a modified quantitative descriptive analysis. Gowe samples significantly differed (P < 0.05) with respect to all the sensory attributes, except for cereal odor and cereal taste (P > 0.05). The principal component analysis plot revealed the effects of raw material and process: Sorghum gowe was differently scored from maize gowe samples (P < 0.05). Gowe types from saccharification step (SSaF, SSaSF) evidenced higher scores with respect to fermented odor (41.7) and acidic taste (47.9), while those without saccharification had lower scores of fermented odor and acidic taste, with values of 18.4 and 16.9, respectively. No significant difference was evidenced with respect to the addition of "non malted flour" before or after saccharification. Regarding consumer testing, three distinct patterns of consumer acceptability were observed, which were grouped as "Sugary gowe likers" (63.1% of consumers) followed by "Sugary and saccharified sorghum gowe likers" (20.6%) and "Pure maize gowe dislikers" (16.3%). Irrespective of the consumers cluster, saccharified malted sorghum gowe without sugar was the unique sample scored more than 6 over 9.

15.
Int J Food Microbiol ; 163(2-3): 231-8, 2013 May 15.
Article in English | MEDLINE | ID: mdl-23571124

ABSTRACT

Yanyanku and Ikpiru made by the fermentation of Malcavene bean (Hibiscus sabdariffa) are used as functional additives for Parkia biglobosa seed fermentations in Benin. A total of 355 aerobic endospore-forming bacteria (AEFB) isolated from Yanyanku and Ikpiru produced in northern and southern Benin were identified using phenotypic and genotypic methods, including GTG5-PCR, M13-PCR, 16S rRNA, gyrA and gyrB gene sequencing. Generally, the same 5-6 species of the genus Bacillus predominated: Bacillus subtilis (17-41% of isolates), Bacillus cereus (8-39%), Bacillus amyloliquefaciens (9-22%), Bacillus licheniformis (3-26%), Bacillus safensis (8-19%) and Bacillus altitudinis (0-19%). Bacillus aryabhattai, Bacillus flexus, and Bacillus circulans (0-2%), and species of the genera Lysinibacillus (0-14%), Paenibacillus (0-13%), Brevibacillus (0-4%), and Aneurinibacillus (0-3%) occurred sporadically. The diarrheal toxin encoding genes cytK-1, cytK-2, hblA, hblC, and hblD were present in 0%, 91% 15%, 34% and 35% of B. cereus isolates, respectively. 9% of them harbored the emetic toxin genetic determinant, cesB. This study is the first to identify the AEFB of Yanyanku and Ikpiru to species level and perform a safety evaluation based on toxin gene detections. We further suggest, that the gyrA gene can be used for differentiating the closely related species Bacillus pumilus and B. safensis.


Subject(s)
Bacteria/classification , Biodiversity , Condiments/microbiology , Fermentation , Hibiscus/microbiology , Seeds/microbiology , Aerobiosis , Bacteria/genetics , Bacterial Load , Benin , Genes, Bacterial/genetics , Genotype , Hydrogen-Ion Concentration , Phylogeny , RNA, Ribosomal, 16S/genetics
16.
J Agric Food Chem ; 59(4): 1178-84, 2011 Feb 23.
Article in English | MEDLINE | ID: mdl-21322653

ABSTRACT

Extracts from leaf sheaths of farmers' varieties of dye sorghum cultivated and used in Benin as a source of biocolorings were analyzed for their anthocyanidin and phenolic contents, as well as their antioxidant capacity. The aim was to identify and quantify the types of anthocyanin and phenolic acids. The total anthocyanin content of the leaf sheaths ranged from 13.7 to 35.5 mg of cyanidin 3-glucoside equivalent/g of dry matter (DM), with an average of 27.0 mg/g. The total anthocyanin content is 90 times higher than levels usually reported in fruits and vegetables. Anthocyanin consisted essentially of apigeninidin and luteolinidin, two 3-deoxyanthocyanidins with many applications in food, beverage, and pharmaceutical industries. The apigeninidin content of the leaf sheaths was 30 times higher than that in cereal bran and ranged from 14.7 to 45.8 mg/g, with an average of 31.3 mg/g. The amount of luteolinidin ranged from 0.4 to 2.4 mg/g, with a mean of 1.2 mg/g. The total phenolic content expressed as gallic acid equivalent averaged 95.5 mg/g. The free phenolic acids identified were benzoic acid, p-coumaric acid, and o-coumaric acid at amounts of 801.4, 681.6, and 67.9 µg/g, respectively. The leaf sheaths of dye sorghum have an antioxidant capacity [3.8-5.6 mmol of Trolox equivalent (TE)/g of DM] much higher than that reported for cereal bran and fruits and vegetables.


Subject(s)
Anthocyanins/analysis , Antioxidants/analysis , Plant Leaves/chemistry , Sorghum/chemistry , Apigenin/analysis , Benzoic Acid/analysis , Coumaric Acids/analysis
17.
Int J Syst Evol Microbiol ; 60(Pt 9): 2193-2198, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19897612

ABSTRACT

Four Gram-positive, catalase-negative, short rod-shaped or coccoid, heterofermentative lactic acid bacterial strains (2L24P13(T), 1L48P15, 1L24P31 and 1L24P34) with unusual phenotypic and genotypic properties were isolated from submerged fermenting cassava on MRS agar. All strains were motile, grew at 15 degrees C, produced dl-lactic acid from glucose with gas formation and produced ammonia from arginine. Acid was produced from d-fructose, d-galactose, d-glucose, lactose, maltose, d-mannose, melibiose, d-raffinose, sucrose, N-acetylglucosamine and d-mannitol, but not from d-arabinose or xylose. 16S rRNA gene sequence analysis revealed that the strains belonged to the genus Weissella and were most closely related to Weissella ghanensis LMG 24286(T). Low DNA-DNA reassociation values were obtained between the isolates and W. ghanensis DSM 19935(T). Based on the genetic and phenotypic results, the strains are considered to represent a novel species, for which the name Weissella beninensis sp. nov. is proposed. The type strain is 2L24P13(T) (=DSM 22752(T)=LMG 25373(T)).


Subject(s)
Fermentation , Lactic Acid/metabolism , Leuconostocaceae/classification , Leuconostocaceae/isolation & purification , Manihot/microbiology , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Leuconostocaceae/genetics , Leuconostocaceae/metabolism , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/genetics
18.
Int J Food Microbiol ; 133(1-2): 22-30, 2009 Jul 31.
Article in English | MEDLINE | ID: mdl-19493582

ABSTRACT

Lafun is a fermented cassava food product consumed in parts of West Africa. In the present work the microorganisms (aerobic bacteria (AB), lactic acid bacteria (LAB) and yeasts) associated with the fermentation of Lafun under traditional conditions have for the first time been studied using a combination of pheno- and genotypic methods. During Lafun fermentation the AB count ranged from 6-7 log(10) CFU/g at the beginning to 9 log(10) CFU/g at the end. Similarly, the number of LAB increased from 5 log(10) CFU/g to 9 log(10) CFU/g during the process while the yeast load increased from 3 log(10) CFU/g at the onset of the fermentation to 5-6 log(10) CFU/g at the end of the fermentation. A total of 168 isolates (31 AB, 88 LAB, and 49 yeasts) were isolated and identified by means of phenotypic tests, PCR-based methods and 16S rRNA gene sequencing. The aerobic bacteria were mostly identified as belonging to the Bacillus cereus group (71%). The B. cereus isolates lacked the genetic determinant specific for cereulide producers but harboured several genes encoding the heat-labile toxins hemolysin BL and nonhemolytic enterotoxin as detected by PCR. The other aerobic bacteria isolated were Gram negative and identified as Klebsiella pneumoniae and Pantoea agglomerans. The dominant LAB were identified as Lactobacillus fermentum (42% of LAB isolates) followed by Lactobacillus plantarum (30%) and Weissella confusa (18%). Seven isolates remained unidentified and constitute probably a novel LAB species. The predominant yeast species associated with Lafun fermentation were Saccharomyces cerevisiae (22% of yeast isolates), Pichia scutulata (20%), Kluyveromyces marxianus (18%), Hanseniaspora guilliermondii (12%), Pichia rhodanensis (8%) and Candida glabrata (8%) as well as Pichia kudriavzevii, Candida tropicalis and Trichosporon asahii at lower incidence (<5% each).


Subject(s)
Bacteria, Aerobic/isolation & purification , Food Microbiology , Lactobacillaceae/isolation & purification , Manihot/microbiology , Vegetables/microbiology , Yeasts/isolation & purification , Africa, Western , Bacteria, Aerobic/genetics , Base Sequence , Colony Count, Microbial , DNA, Bacterial/isolation & purification , Fermentation , Humans , Lactobacillaceae/genetics , Polymerase Chain Reaction , RNA, Ribosomal, 16S , Yeasts/genetics
19.
Plant Foods Hum Nutr ; 59(3): 93-9, 2004.
Article in English | MEDLINE | ID: mdl-15678714

ABSTRACT

Color and taste are permanent features of amala, a traditional thick paste obtained from yam chips flour. To assess these attributes, 23 yam chips presenting various quality attributes were processed. The sensory attributes of their derived amala were determined and some biochemical characteristics of yam flours measured. A panel defined five main taste attributes for amala: sweetness, bitterness, acidity, fermented, and roasted tastes. Amala color was measured instrumentally and sensory scores were highly correlated with flour biochemical analyses; amala sweetness was positively correlated with glucose and fructose content of the flour, whereas amala acidity and fermented taste were linked to organic acids and lactic acid contents of flour, respectively. In addition, darkness, bitterness, and roasted tastes of amala could be tightly predicted by multiple regression analysis from phenolic compound and glucose-fructose contents. Phenolic content of yam flour plays thus a key role on sensorial quality of amala. However, polyphenol oxidase and peroxidase activities were almost null in yam flours and their specific role on yam flour phenolic content needs to be clarified.


Subject(s)
Color , Dioscorea/chemistry , Flour/analysis , Taste , Africa, Western , Catechol Oxidase/metabolism , Chemical Phenomena , Chemistry, Physical , Dioscorea/enzymology , Flour/standards , Humans , Peroxidase/metabolism
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