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The aim of this study is to find out the appropriate fermentation conditions of Jerusalem artichoke powder (JAP) based media to obtain light beverage containing inulin.

JAP water suspension or filtrate were used for preparation of growth media with or without enzymatic hydrolysis of inulin for fermentation by Zymomonas mobilis 113 “S” or Saccharomyces cerevisiae.

If enzymatic hydrolysis of inulin was not used significantly higher amount of inulin (7.42 per cent) was unconverted by Z. mobilis than by S. cerevisiae (2.22 per cent) while the ethanol concentration was much higher (2.86 per cent) after S. cerevisiae fermentation than after Z. mobilis fermentation (1.21 per cent). Considerably more ethanol was produced by Z. mobilis during co‐fermentation with Fructozyme L of JAP suspension filtrate (5.98 per cent) and suspension (4.96 per cent). Analyses of volatile components of fermentation broths showed that for production of inulin containing light beverages the best was Z. mobilis fermentation of JAP water suspension or filtrate without enzymatic treatment. FT–IR spectroscopy can be used as a quick semi‐quantitative method for evaluation of inulin content.

JAP – containing not only inulin but all tuber ingredients, was used as a media for ethanol fermentations by Z. mobilis 113 “S” or S. cerevisiae with or without hydrolysis of inulin. It was shown that Z. mobilis fermentation broths containing 7.42 per cent of inulin can be used as beverage with prebiotic‐dietary fibre benefits. The taste of this product can be regulated by appropriate fermentation conditions and the concentration of fructose and ethanol.

This study aims to assess the effect of water variation on bioethanol production from cassava peels (CP) using Saccharomyces cerevisiae yeast as the ethanologenic agent.

The milled CP was divided into three treatment groups in a small-scale flask experiment where each 20 g CP was subjected to two-stage hydrolysis. Different amount of water was added to the fermentation process of CP. The fermented samples were collected every 24 h for various analyses.

The results of the fermentation revealed that the highest ethanol productivity and fermentation efficiency was obtained at 17.38 ± 0.30% and 0.139 ± 0.003 gL⁻¹ h⁻¹. The study affirmed that ethanol production was increased for the addition of water up to 35% for the CP hydrolysate process.

The finding of this study demonstrates that S. cerevisiae is the key player in industrial ethanol production among a variety of yeasts that produce ethanol through sugar fermentation. In order to design truly sustainable processes, it should be expanded to include a thorough analysis and the gradual scaling-up of this process to an industrial level.

This paper is an original research work dealing with bioethanol production from CP using S. cerevisiae microbe.

1. Hydrolysis of cassava peels using 13.1 M H₂SO₄ at 100 ^oC for 110 min gave high Glucose productivity

2. Highest ethanol production was obtained at 72 h of fermentation using Saccharomyces cerevisiae

3. Optimal bioethanol concentration and yield were obtained at a hydration level of 35% agitation

4. Highest ethanol productivity and fermentation efficiency were 17.3%, 0.139 g.L⁻¹.h⁻¹

Hydrolysis of cassava peels using 13.1 M H₂SO₄ at 100 ^oC for 110 min gave high Glucose productivity

Highest ethanol production was obtained at 72 h of fermentation using Saccharomyces cerevisiae

Optimal bioethanol concentration and yield were obtained at a hydration level of 35% agitation

Highest ethanol productivity and fermentation efficiency were 17.3%, 0.139 g.L⁻¹.h⁻¹

This study aims to examine the effect of traditional fermentation on gari’s total heavy metal and mineral nutrient content.

This study used a quantitative approach, descriptive-analytical design to baseline the risk of heavy metals and experimental design to assess the effect of traditional fermentation. Data were analyzed using descriptives, univariate and multivariate analysis.

Although gari is rich in mineral nutrients (total calcium 3.9 ± 0.1 g/kg, copper 5.5 ± 0.02 mg/kg, iron 97.1 ± 5.8 mg/kg, potassium 9.1 ± 0.29 g/kg and zinc 3.4 ± 0.11 mg/kg), the significant levels of heavy metals (total arsenic 1.2 ± 0.01, cadmium 2.5 ± 0.04, lead 1.7 ± 0.01, mercury 2.8 ± 0.01 and tin 1.7 ± 0.02 mg/kg) present are a cause for concern. The results further suggested that traditional fermentation has reductive effects on some heavy metals and stabilizing or concentrating effects on mineral nutrients.

This paper provides evidence that traditional fermentation may have exploitable differential effects on heavy metal contaminants and mineral nutrients that should be further explored.

Thise study reports fermentation implications for mitigating food with high heavy metal contaminants with minimal nutrient loss.

This study fulfills an identified need to optimize traditional fermentation to ensure food safety and nutrient security.

The purpose of this paper is to evaluate the possibility of a new biocatalyst prepared by kefir cells immobilization on grape stalks (GS) to reduce quickly and efficiently the Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) of the waste whey during its fermentation producing potable ethanol.

Many batch whey fermentations were carried out in order the effect of various conditions (pH, temperature) on 14C-labeled lactose uptake rate by the GS-immobilized kefir cells and consequently on fermentation rate as well as on ethanol production and whey BOD and COD reduction to be determined.

It has been illustrated that GS-biocatalyst was suitable for whey BOD and COD reduction by about 32 and 25 percent, respectively during whey alcoholic fermentation at 30°C and pH 5.5 in only ten hours, producing about 3.30 percent w/v of ethanol.

The findings of this research may enhance the existing literature on whey exploitation, for the first time focussing on the use of cheap and abundant GS as support for kefir immobilization during whey fermentation, which is potentially acceptable by industries in order to reduce fast and easily the whey polluting load and produce ethanol.

The purpose of this paper is to assess the potential of papaya juice fermentation and to evaluate the kinetic changes of volatile organic compounds (VOCs) produced during fermentation by three commercial wine yeasts.

Laboratory‐scale fermentations were carried out in papaya juice using three commercial wine yeasts Saccharomyces cerevisiae var. bayanus strains EC‐1118 and R2, and S. cerevisiae MERIT.ferm. Brix, pH, optical density and yeast cell count were determined during fermentation. VOCs were analysed by headspace‐solid phase microextraction with gas chromatography‐mass spectrometry‐flame ionization detector (HS‐SPME‐GC‐MS/FID).

During fermentation, the three wine yeasts grew actively and showed similar growth patterns. Changes in Brix and pH were similar among the three yeasts. A range of VOCs were produced during fermentation including fatty acids, alcohols, acetaldehyde, esters and acetoin. Esters were the most abundant VOCs produced. Some VOCs indigenous to the papaya juice such as benzaldehyde, β‐damascenone and benzyl isothiocyanate were consumed during fermentation. Some VOCs increased initially, and then decreased during fermentation. Overall, the profiles of VOC changes during fermentation were similar among the three yeasts with some differences observed.

The paper suggests that papaya fermentation with S. cerevisiae yeasts are likely to result in papaya wine with similar flavours. New approaches are required to produce papaya wine with distinct flavours and to enable differentiation of papaya wines by exploiting non‐Saccharomyces yeasts in conjunction with Saccharomyces yeasts and/or by adding selected nitrogen sources.

Mixed fermentation with Saccharomyces cerevisiae and non-Saccharomyces yeasts has become an oenlogical tool to improve wines’ organoleptic properties. However, the maximum utilization of this method is dependent upon understanding the influence of mixed cultures on the physiology of S.cerevisiae and non-Saccharomyces yeasts.

In this study, the supernatants from 48 h mixed-culture fermentation were added to the pure cultures of Issatchenkia orientalis and Saccharomyces, respectively. And the authors used RNA sequencing to determine the transcriptome change of I.orientalis and S.cerevisiae in a mixed culture.

The results showed that multiple genes associated with cell growth and death were differentially expressed. Genes related to biosynthesis of amino acids were enriched among those upregulated in the mixed-fermentation supernatant. Meanwhile, the differential expression level of genes encoding enzymes essential for formation of aroma compounds was found in the single and in the mixed fermentation. The high expression level of molecular chaperones Hsp70, Hsp90 and Hsp110 suggests that metabolites of mixed-culture fermentation may lead to aggregation of misfolded proteins. Moreover, upregulation of ethanol dehydrogenase I ADH1 in the mixed-culture fermentations was highlighted.

This is the first time that RNA-seq was used to analyze changes in the transcriptome of mixed cultures. According to the results the authors’ manuscript provided, an integrated view into the adaptive responses of S.cerevisiae and non-Saccharomyces yeasts to the mixed-culture fermentation is benefit for the potential application of S.cerevisiae and non-Saccharomyces yeasts in fruit wine brewing.

This study aims to determine the probiotic potential of Lactobacillus rhamnosus GR-1 from Fiti sachets, in four widely consumed pulses, namely, black-eyed pea, pigeon pea, kabuli chickpea and desi chickpea. The secondary objective was to determine the viability of the fermented pulses during 21 days of storage at 4°C.

Each pulse sample was mixed with a Fiti sachet (one gram of freeze-dried consortium of Lactobacillus rhamnosus GR-1 and Streptococcus thermophilus C106) and fermented for up to 120 h. To assess the samples’ storage potential, they were refrigerated at 4°C for 21 days. Microbial enumerations and pH measurements were collected during fermentation and storage to determine the viability and fermentation potential of Lactobacillus rhamnosus GR-1 and Fiti, respectively.

There was a significant (p = 0.01) difference in mean microbial counts in all pulse samples throughout fermentation. At 24 h of fermentation, the mean bacterial count of Lactobacillus rhamnosus GR-1 in black-eyed pea, pigeon pea, kabuli chickpea and desi chickpea were 1.32 × 10⁹ ± 0.11, 1.01 × 10⁹ ± 0.16, 1.52 × 10⁹ ± 0.14 and 0.80 × 10⁹ ± 0.05 CFU/mL, respectively. Fermentation of pigeon pea, kabuli chickpea and desi chickpea at 48 h yielded the highest bacterial count for Lactobacillus rhamnosus GR-1 while black-eyed pea reached its highest bacterial count at 72 h of fermentation. The bacterial concentration of all pulse samples remained at around 10⁹ CFU/mL during the refrigeration period of 21 days at 4°C. Furthermore, the pH of all pulse samples were below 4.6 during both fermentation and refrigerated storage.

Since 2004, the Fiti initiative has economically empowered hundreds of women in East Africa by teaching them how to produce and sell probiotic yogurt containing Lactobacillus rhamnosus GR-1. As a result, Fiti probiotic yogurt was made accessible to vulnerable populations in East Africa who face malnutrition, infectious diseases and environmental toxins. Because of recent climatic changes, milk has become more expensive and inaccessible for local communities. Furthermore, this study found that black-eyed pea, pigeon pea, kabuli chickpea and desi chickpea can be viable and non-diary probiotic alternatives to the Fiti probiotic yogurt in Eastern Africa. This is also the first study of its kind to provide preliminary evidence showing pulses as non-dairy alternatives to Fiti probiotic yogurt.

The purpose of this paper is to examine pure culture isolates from traditionally fermented product of African oil bean seeds (ugba) with a view to identifying the appropriate starters.

The isolates were purified and characterized, and used singly and in combination to ferment freshly prepared oil bean seed slices for 72 h at 37^○C. The pH and microbial load of fermenting beans were monitored daily, and organoleptic tests using semi‐trained panelists were employed to assess the fermented products based on quality attributes of flavour, appearance, texture and overall acceptability.

The isolates included Bacillus subtilis, Bacillus licheniformis and Pseudomonas fluorescens. Total viable counts ranged from 1.3 × 10⁷‐9.3 × 10⁹ cfu/g, 7.0 × 10⁶‐4.0 × 10⁹ cfu/g, and 3.0 × 10⁶‐1.5 × 10⁹ cfu/g, respectively for the three isolates; while counts for the mixed culture fermentation ranged from 7.0 × 10⁶‐1.72 × 10¹⁰ cfu/g. The mixed culture fermentation gave the best rated product, indicating a synergy among the isolates. The pH values increased steadily in the samples fermented by Bacillus sp. and the mixed culture organisms, showing that the production of ugba follows alkaline fermentation pattern.

The African oil bean seed fermentation is a bacterial mixed culture and alkaline fermentation. The major organisms involved are B. subtilis and B. licheniformis, while the P. fluorescens was insignificant.

Most of the local fermentations in Africa, including oil bean fermentation, are still at the wild, natural inoculation level. The present study has helped in understanding of the fermentative organisms involved in Pentaclethra seed fermentation, and gave insight into an optimized ugba production.

Biopigments, natural colors from microbiological origin are of great interest because of their potential advantages over synthetic colorants. Therefore, this paper aims to evaluate the best possible fermentative conditions for the maximum production of biopigment using solid state fermentation and submerged fermentation by Monascus purpureus MTCC 369.

The biopigment was produced using solid state fermentation and submerged with optimized substrate to achieve higher yield. The statistical analysis was carried out using a Microsoft Excel ® (Microsoft Corporation).

On comparative analysis, it was observed that solid state fermentation resulted significant accumulation of biopigment (9.0 CVU/g) on the 9th day in comparison to submerged fermentation (5.1 CVU/g) on the 15th day.

Results revealed that sweet potato peel powder and pea pods provides necessary nutrients required for mycelial growth, and biopigment production, therefore, can be used as potent substrate for biopigment production by Monascus purpureus MTCC 369. Extracted color can be used in confectionery, beverages and pharmaceutical industries.

This work focuses on utilisation of waste for production of pigment as alternative source to synthetic colorant, and few studies have been carried out using wastes, but no work has been carried out on sweet potato peel to the best of the authors’ knowledge.

The purpose of this study was to accelerate the fermentation process of minced mackerel fish (Scomber scombrus L.) mixed thoroughly with 20 per cent salt (w/w) and hydrolyzed by 0.2 and 0.4 per cent bromelain at 37°C.

S. scombrus L. was mixed thoroughly with 20 per cent salt (w/w) and hydrolyzed by the bromelain at levels of 0.2 and 0.4 per cent at 37°C. The physicochemical and sensory properties were evaluated after 60 and 90 days.

In a comparison of all of the aforementioned treatments, the results showed that the samples with higher bromelain levels (0.4 per cent) had higher concentrations of formal nitrogen (622 mg/100 mL) and total volatile base nitrogen (TVB-N, 0.3 g/dL) after 90 days of fermentation (p < 0.01) . The sample with 0.4 per cent bromelain showed total free amino acids content of 13.3 g/100 g after 90 days of fermentation (p < 0.01). High levels of total fatty acids (15.6 mg/100 g) were found in samples treated with 0.4 per cent bromelain and allowed to ferment for 90 days (p < 0.01). The sauce colour became significantly highly saturated (p < 0.01) with the increase in fermentation time. Chroma was significantly increased by 44 and 66 per cent in fermented sauce samples with 0.2 and 0.4 per cent bromelain during fermentation for as long as 90 days (p < 0.01). Moreover, the addition of bromelain (0.4 per cent) resulted in mackerel fish sauce that was organoleptically preferred at the end of fermentation.

The results showed that an acceptable fish sauce could be produced from mackerel fish with supplementation with 0.4 per cent of bromelain, which reduced the fermentation time to 90 days and resulted in the most satisfactory results without compromising the product quality.