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The purpose of this paper is to identify and analyse the fermentative properties of a strain of indigenous Wickerhamomyces anomalus (W. anomalus) from Rosa roxburghii Tratt (R. roxburghii).

Morphological and molecular methods were used to determine the species of the selected strain W. anomalus C11. The physiological tolerances to glucose, ethanol, citric acid and sulphur dioxide (SO₂) were further assessed by checking the growth of cells, and the oenological performances were proved to measure the related fermentative properties of R. roxburghii wines.

The W. anomalus C11 strain could be grown faster than commercial S. cerevisiae X16 in its logarithmic growth period and had preferable tolerances to glucose, ethanol, citric acid and SO₂. Moreover, this strain of native R. roxburghii yeast W. anomalus C11 produced less sulphuretted hydrogen and had a higher β-glucosidase activity. Furthermore, W. anomalus C11 could reduce the volatile acids, reduce the sourness and enhance volatile aroma richness and complexity of R. roxburghii wines including types of aroma and content thereof. Taken together, the R. roxburghii native yeast W. anomalus C11 may have potential for use in R. roxburghii winemaking.

(1) The fermentative properties of a strain of indigenous W. anomalus (named as C11) from R. roxburghii was evaluated. (2) The strain of W. anomalus C11 had preferable tolerances to glucose, ethanol, citric acid and SO₂. (3) This strain of native R. roxburghii yeast W. anomalus C11 produced less sulphuretted hydrogen and had a higher ß-glucosidase activity. (4) W. anomalus C11 could reduce the volatile acids, reduce the sourness and enhance volatile aroma richness and complexity of R. roxburghii wines including types of aroma and content thereof.

Wheat is the staple food in many parts of the world and bread is one of the most important products of wheat flour. There is a need for innovations in bread making to increase its shelf life and consumer's attraction. Fermentation is mostly done by yeast but it does not produce appreciable amounts of organic acids, which are required to enhance the shelf life of bread. The present study aims to determine the effect of bacterial and yeast culture blends on the quality and shelf life of sourdough bread and to observe the sugar utilization during fermentation.

Three treatments were made using different blends of bacterial cultures (homo‐fermentative and hetero‐fermentative) and baker's yeast compared with a control having only baker's yeast. Chemical analysis, sugar utilization (Sucrose, glucose and fructose) through high performance liquid chromatography, sensory characteristics (both internal and external) and microbial count (Bacterial and fungal count) for each treatment were conducted at different storage intervals.

The hetero‐fermentative bacteria i.e. Lactobacillus plantarum along with baker's yeast exhibited the best results regarding the utilization of sugars during fermentation (after 3 h of fermentation 0.0158 mg/ml sugar remained), objective evaluation of bread and its sensory characteristics. The bread prepared using the blend of hetero‐fermentative bacteria (0.5 per cent) and yeast (0.5 per cent) also showed greater resistance against bacteria (9×10¹ cfu/g after 60 h of storage) and mold (1.1 ×  10² cfu/g after 60 h of storage) growth.

Hetero‐fermentative bacteria along with baker's yeast can be utilized in sour dough to improve major bread characteristics. This study is a step further in improving the shelf life of sourdough.

Presently only baker's yeast is being used by bread industry for fermentation purpose but a blend of bacterial culture along with baker's yeast can give better performance for better quality and shelf life of the bread.

Increased ethanol accumulation during ethanol fermentation generates stress in yeast cells, which finally reduces the fermentation performance and efficiency. Trehalose, a potential stress protectant, has been reported to regulate the response of yeast to diverse environmental stresses. This study aimed to explore how exogenous trehalose application affects the survival, transcriptome and antioxidant enzymes of Wickerhamomyces anomalus grown under ethanol stress conditions.

Exogenous trehalose was applied to the growth condition of W. anomalus, and optical densitometric method was used to detect contents of intracellular trehalose and MDA and activities of CAT and SOD. The survival was evaluated using spot analysis. Differentially expressed genes (DEGs) were identified through transcriptomics analysis.

The results showed that ethanol stress induced the accumulation of intracellular trehalose, with further exogenous trehalose application improving the survival and alleviating oxidative stress in ethanol-stressed W. anomalus. Transcriptomic results showed that trehalose has pleiotropic regulating effects on ethanol-stressed W. anomalus since most DEGs annotated to energy metabolism, amino acid metabolism, translation, folding, sorting and transport were affected post trehalose addition. Therefore, it is found that trehalose protected W. anomalus against ethanol stress, and these findings provide interesting insights into the mechanistic role of trehalose in improving ethanol stress tolerance of W. anomalus.

(1) Protective effect of exogenous trehalose addition on the survival of ethanol-stressed W. anomalus was proved. (2) Exogenous trehalose addition could partly alleviate oxidative stress induced by ethanol stress and affect transcriptome in W. anomalus.

The purposes of this paper are to determine the nutritional composition of the pulp and its antioxidant activity; study the effect of drying and storage on the nutritional composition and antioxidant of the pulp; investigate the effect of de-bittering using fermentative microbes, sodium carbonate and polyethylene glycol (PEG) on antioxidant of the pulp, and to study the shelf-life and sensory evaluation of de-bittered pulp products.

The ripe fruits of palmyra (Borassus flabellifer L) were collected around Kupang city, Indonesia. The pulp was extracted with different techniques. The fresh pulp was directly analyzed for its nutritional and antioxidant properties. The rest of the pulp was de-bittered, dried and used for further treatments and products development. The de-bittered pulp was used to make chips, stick cracker, and jelly sweet. Fresh products were sensory evaluated by 30 semi-trained panelists. For shelf-life analysis, products were wrapped and/or packed with different thickness of food grade plastic, plastic-alumina foil, or mica stopples and kept at different temperatures (30, 40 and 50^oC) for one month.

The fresh pulp contains carotenoids (609.10 mg per kg of pulp), vitamin C (461.40 mg per kg of pulp), polyphenols (270 mg per kg of pulp) and anthocyanin (53.90 mg per kg of pulp). Free radical scavenging activity of the dried pulp (water content of 11.60 percent) was 93.4 percent. Several techniques including fermentation, sodium carbonate, and PEG treatment have been successfully developed to reduce the bitterness of the pulp without significantly reducing its antioxidant activities. Food products (chips, stick cracker, and jelly sweet) have then been developed and have got positive response from panelist.

Pulp of fruit is a potential source of antioxidants, i.e. carotenoids (pro vitamin A), vitamin C, and polyphenols. The pulp potentially can be used in fresh and dried form for functional food. The bitterness of the pulp can be significantly reduced using fermentation, sodium carbonate or PEG treatment. The pulp can be utilized for producing chips, crackers, and semi moist food products.

First, pulp of the palmyrah fruit can be easily extracted using water. Second, the bitterness of the pulp can be reduced by using traditional fermentation starter. Third, many type of food products can be developed using the palmyrah pulp.

This effort offers opportunity for farmers to optimize the use of palmyrah pulp for functional food. It will provide new jobs and increase the income of farmer at East Nusa Tenggara Province.

The study has revealed that pulp of palmyrah fruit is a source of antioxidants: carotenoids (pro vitamin A), vitamin C, and polyphenols. The pulp potentially can be used in fresh and dried form for functional food. The bitterness of the pulp can be significantly reduced using fermentation, sodium carbonate, and PEG. The pulp can be utilized for producing chips, crackers, and semi moist food products.

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.

Circular 381 MINISTRY OF HEALTH, Whitehall, S.W. 1. 20th March, 1923. I am directed by the Minister of Health to state that he has received communications from a number of local authorities with regard to the presence of boric acid in cake, some samples (especially of sponge cake) having been found to contain a somewhat high proportion of this preservative.

Spoilage due to yeast and mould growth is a major issue for yoghurt quality and shelf‐life. There is a need to develop natural alternatives to chemical preservation. The purpose of this paper is to determine the effectiveness of mycocinogenic yeast Williopsis saturnus var. saturnus as a biocontrol agent against spoilage yeasts and moulds in plain yoghurt.

Yoghurts were prepared from reconstituted skim milk and were challenged with spoilage yeasts and moulds. The treatment contained the added mycocinogenic yeast and the control without. All yoghurts were incubated at 30^○C. Yeast and mould growth were determined by observing gas formation and mould colony occurrence at regular intervals.

W. saturnus var. saturnus inhibited growth of lactose‐fermenting and galactose‐fermenting yeasts (Candida kefir and Kluvyveromyces marxianus), and lactose non‐fermenting but galactose fermenting yeasts (strains of Saccharomyces cerevisiae and Saccharomyces bayanus). The yeast also inhibited growth of dairy moulds including Byssochlamys, Eurotium and Penicillium.

The inhibition of this mycocinogenic yeast against yeasts and moulds was dependent upon the concentration of the latter. Thus, hygiene and good manufacturing practice are essential in order to keep the contaminant load down and to ensure the effectiveness of the mycocinogenic yeast.

The use of mycocinogenic yeast to control spoilage yeasts and moulds in yoghurt is a novel approach with a potential to minimise yoghurt spoilage and extend the shelf‐life of yoghurt.

This paper aims to isolate fungal strains producing natural colours, explore their application as colourant in paints and develop cost-effective durable natural paints.

Fungal strains producing natural colours of different shades were isolated. Colourant production was carried out by fermentation method. Natural lime, milk, oil-in-water emulsion paints using natural microbial colours and eco-friendly ingredients were prepared. Bio-paint applications were carried out and evaluated.

Our results indicate that microbes in general and fungi in specific represent dependable source of variety of natural colours, and cost-effective durable natural paints can be prepared with commonly available natural ingredients using scientific information based on history of paints.

Natural colours are gaining importance because of their use in health, nutrition, pharmaceutical, textile and environmental applications. Nature is quite rich in several types of colourants. Chemical synthesis of synthetic dyes is complex and not environmental friendly. Microbial dyes manufactured can evade inherent environmental problems of synthetic dyes and offer significant opportunity as a colourant in paints. However, only generally regarded as safe microbial strains are to be considered for colour production.

Choosing natural alternatives to protect the health and environment is the need of hour. Fungal colourants are relatively more stable and robust and offer significant opportunity as a colourant in paints. Cost-effective durable natural paints can be prepared using selected stable fungal colourants with commonly available natural ingredients. High diversity of rich and complex natural colourants can be obtained from microorganisms. With the available techniques of fermentation, natural colours can be produced in large quantities of on an economically viable scale and explored for their applications.

Bio-paints are eco-friendly natural paints, low volatile organic compounds (VOC) paints or organic paints alternate to conventional paints. Most of these natural paints are durable, breathable, prevent moisture problems, contribute to a positive room climate, use safer technology and are less energy-intensive than conventional latex paints to produce. These paints improve indoor air quality and reduce urban smog and offer beneficial characteristics such as low odour, excellent durability and a washable finish.

Many of the old art works that still survive today are a tangible proof and evidence of beauty and durability of natural paints. Organic materials used in these paints include natural pigments of mineral, plant and animal origin and other raw biodegradable ingredients. Successful commercialisation of many microbial pigments for food and textile applications is reported in literature. Therefore, present research work aims at developing natural paints using microbial pigments and recipes that have been successfully used by people for years.

Monascus pigment was widely applied in food processing industry as functional additive, so more attention was paid to the fermentation optimization of pigment production. Therefore, this paper aims to evaluate the best possible fermentative conditions for maximum production of biopigment using submerged fermentation (SFM) and solid state fermentation (SSF) by Monascus purpureus HBSD 08.

The biopigment was produced by using an SMF and an SSF with optimized substrate to achieve higher yield. The antioxidant activity was evaluated by DPPH radical scavenging ability, superoxide anion radical scavenging ability and hydroxyl radical scavenging ability. The pigment composition was analyzed by thin layer chromatography.

Maximum Monascus pigment production (79.6 U/ml and 1,102 U/g) were obtained under an SFM and an SFF. The antioxidant activity of the pigment in an SFM was significantly higher than that in an SFM. The composition of pigment was not different in an SFM and an SFF.

The study developed new conditions, and Monascus strain was a candidate for producing pigment in an SFM and an SFF. To the authors’ best knowledge, this is a first attempt toward comparative evaluation on antioxidant capacity and composition between pigment in an SSF and an SFM. This result will serve for Monascus pigment production.

The purpose of this paper is to apply okara flour in the elaboration of a product, verifying the effect of the fermentation by Lactobacillus plantarum BG 112 on the antihypertensive activity and to develop probiotic sauce with gums and low lipid content.

During the fermentation process, the inhibitory activity of angiotensin-converting enzyme (ACE) and production of organic acids were determined. The simplex-centroid mixture of guar gum, xanthan gum and pregelatinized cassava starch was used for studying the variables water holding capacity, viscosity and firmness. Counts of probiotics and in vitro survival of probiotics in simulated gastrointestinal conditions were made.

The fermented soymilk showed ACE inhibition capacity above 50 percent with 32 h of fermentation, increasing the levels of lactic acid and acetic acid progressively. Based on the regression analysis and response surfaces, the binary mixture with guar gum and xanthan was chosen as the most suitable for the formulation of the sauce, having over 30 days of storage counts above 8.5 log CFU.g⁻¹ and above 6 log CFU.g⁻¹ after simulation of gastrointestinal conditions. The global acceptance was 7.0 corresponding to the moderately liked.

The findings suggest that the sauce developed has been well accepted by potential consumers and can be incorporated into the diet and can result in health benefits for the consumer when regularly ingested. The fermentation process of soymilk promoted an increase in antihypertensive capacity. Despite the reduction in viable cell counts throughout storage, counts remained high in the product, having a high survival rate after exposure under simulated gastrointestinal conditions.

The use of okara flour in the diet is viable and helps to improve the nutritional composition of foods. The use of okara flour in sauce showed potential applicability and could be incorporated into different products. The fermentation process of soymilk with okara flour produces benefits beyond the sensorial characteristics. The elaborated probiotic sauce presented physical–chemical and microbiological stability throughout the storage, being an alternative for people with food restrictions.