Background: Fermentation is an age old technique of preserving food in many communities. A wide r... more Background: Fermentation is an age old technique of preserving food in many communities. A wide range of fermented products are prepared by varying the types of raw materials, utensils, and fermentation times. Several fermented foods are consumed in Swaziland. A survey of the types of fermented foods, preparation methods, and utensils used was done in the Hhohho region of Swaziland. The current study aimed at documenting the preparation methods of emahewu, emasi, umcombotsi, and buganu at household levels. Methods: Detailed fermentation steps were documented for umcombotsi, emahewu, buganu, and emasi. Five constituencies, called tinkhundla, were randomly selected from the 14 found in the Hhohho region of Swaziland. At each inkhundla, households that were known to regularly prepare the fermented foods were identified with the assistance of local community leaders and were interviewed. A semistructured questionnaire was used for the face-to-face interviews. Results: With respect to preparation procedures and practices, all respondents indicated that they had prepared different fermented foods at one time or another. The most commonly prepared and readily available fermented foods were umcombotsi (alcoholic beverage), emahewu (nonalcoholic beverage), buganu (marula wine), and emasi (spontaneously fermented milk). Both men and women indicated that they prepared umcombotsi, and only women reported that they prepared emahewu, buganu, and emasi. Umcombotsi was mainly prepared for sale, while buganu, emahewu, and emasi were for sale as well as for household consumption. Umcombotsi was mostly prepared by mixing maize meal, unmilled sorghum malt (magayiwe), and brown sugar (3 kg) in water (20 L). The initial stage involved cooking the mixture to gelatinize the starch, followed by fermentation at ambient temperature (25e30 C) for about 72 hours. The whole preparation process takes about 4e5 days. Emahewu was prepared by mixing maize meal (1 kg) with water (5 L) and cooking to make a soft porridge. The cooled porridge was left to ferment at room temperature. Some reported adding sugar or a peeled potato to aid the fermentation process. Emasi was prepared by letting raw milk to naturally ferment at room temperature (25e30 C) in either metal or plastic containers (buckets) for 2e3 days. Buganu was prepared from marula fruit (amaganu) juice and pulp mixed with water (10 L) and sugar (2 kg). The mixture was allowed to ferment at ambient temperature for about 3 days, sieved, and then served. Conclusion: Umcombotsi, emahewu, buganu, and emasi were the fermented foods commonly prepared at a household level in the Hhohho region, Swaziland. The main ingredient used for preparing umcombotsi and emahewu was maize meal. Unmilled sorghum malt was also added during preparation of umcombotsi. However, typically no malt was added during the preparation of emahewu. Buganu and emasi also play an important role in the diet and socioeconomic activities of the population in Swaziland.
Summary The effect of temperature on the growth of yeasts during the production of Sethemi, South... more Summary The effect of temperature on the growth of yeasts during the production of Sethemi, South African naturally fermented milk (NFM), was studied by incubating raw milk and milk inoculated with selected yeast strains at 7, 15, 25 and 37 °C. The different temperatures were selected to represent the average ambient temperatures around Bloemfontein, South Africa, during winter, spring, summer, and in the human body, respectively. The yeast strains used had previously been isolated from Sethemi and identified as Kluyveromyces marxianus, Saccharomyces cerevisiae, Candida albicans and Debaryomyces hansenii. The yeast strains were inoculated into raw milk separately and also as a mixture of the four strains. The yeast counts, lactic acid bacteria counts and pH were monitored over a period of 20 days. It was observed that although all the yeast strains grew in the milk at all temperatures, the fastest growth was at 37 °C but there was a prolonged lag phase at 7 and 15 °C. The highest ye...
Harnessing the freely available source of energy from the sun offers a number of additional benef... more Harnessing the freely available source of energy from the sun offers a number of additional benefits. Not least of these benefits is the fact that solar energy is an environmentally sustainable alternative. A four-wing compound parabolic concentrator (CPC) was designed as a modification of the regular non-imaging CPC concentrator that has a widespread use as solar collector. The design is intended to increase the angle of acceptance as well as concentration of energy from the sun. The conceptual design, mathematical formulation as well as construction and initial trial results have been presented in this paper. Pilot trials of the four-wing concentrator used for sanitizing both liquid and waste products produced satisfactory results. Improvements in terms of design as well as material used for construction and better preservation of heat can be considered further in the future research.
Food safety is a global issue, affecting food production and processing. The study assessed the m... more Food safety is a global issue, affecting food production and processing. The study assessed the microbiological quality of commercially dried fruits and home dried fruits and vegetables in Lesotho. Moisture content, pH and water activity of the fruits and vegetables were determined using standard methods. Nine different growth media were used for microbial evaluation. Moisture content and water activity were within World Health Organisation guidelines for dried fruits and vegetables. Fungi counts ranged from 2.0x10 2 to 8.7x10 5 CFU g-1 , and dried pumpkin leaves recorded the highest. More than 45% and 38% of the samples exceeded the fungal and total aerobic counts recommended by WHO, respectively. Possible pathogens of the genera Salmonella, Shigella, Bacillus and other Enterobacteriaceae were isolated from home dried samples. Faecal coliforms were detected in 55% of the home dried food products. More than 60% of the samples recorded higher microbial levels than recommended. While half of commercially dried fruits exceeded international standards, all home dried fruits and vegetables recorded unacceptably high levels of fungal contamination. The presence of possible pathogenic organisms in these foodstuffs suggest a potential public health hazard to consumers. Sanitation and personal hygiene, especially during home-based food processing, needs improvement.
Edible wild plants were investigated as potential sources of antioxidants and prebiotics to benef... more Edible wild plants were investigated as potential sources of antioxidants and prebiotics to benefit human health. Antioxidant activity, ascorbic acid and total dietary fibre contents were determined in edible wild plants from Lesotho, Swaziland and South Africa. Pure probiotic strains of Bifidobacterium animalis subsp. animalis (ATCC 25527), Lactobacillus rhamnosus (TUTBFD) and Lactobacillus acidophilus (ATCC 314) were cultured in broth containing edible wild plant extracts to assess their prebiotic activity. Cyperus esculantus had the highest arscobic acid content of 603±64.1 mg/100 g edible dry plant material followed by Rosa rubiginosa (500.8±48.8 mg/100 g). The two plants had IC50 of 10.7±0.2 µg/mL and 47.8±0.2 µg/mL for DPPH inhibition, respectively. Forty percent (40%) (n=30) of the edible wild plants had significant (p<0.01) total antioxidant activity (IC50<60 µg/mL) and high ascorbic acid content (>200 mg/100 g). Nasturtium officinale reported the highest yield for ...
International Journal of Food Microbiology, Sep 1, 2003
Yeasts are present in indigenous African fermented milks in numbers up to log 8 cfu g(-1), togeth... more Yeasts are present in indigenous African fermented milks in numbers up to log 8 cfu g(-1), together with a varied lactic acid bacteria (LAB) flora, and therefore potentially contribute to product characteristics. However, interaction between yeasts and LAB in these products has received little notice. In studies of indigenous fermented milk in Zimbabwe and Uganda, many samples contained more than one species of yeast, but Saccharomyces cerevisiae was most commonly isolated. Other frequent isolates were other species of Saccharomyces and several species of Candida. Most yeast isolates were lactose-negative but usually galactose-positive. Some strains assimilated lactate and citrate. The growth in milk of strains of yeasts and LAB, isolated from naturally soured milk in Zimbabwe, and their interaction when selected pairs of strains were grown together has been studied. Interactions were shown by the significantly different amounts of certain metabolites produced, such as acetaldehyde and malty aldehydes, when co-cultures were compared to pure cultures. Preliminary sensory acceptance tests did not show, however, that milks made from a co-culture with Candida kefyr and LAB were preferable to the pure LAB culture. Further work is still needed to elucidate the reactions that may be taking place in fermented milk between varying LAB and yeast populations. The potential for use as starter cultures depends on various aspects, including the final product being prepared. The role of other microorganisms in naturally fermented milk also needs to be studied.
The volatile organic compounds present in 18 Zimbabwean naturally fermented milk (amasi) samples ... more The volatile organic compounds present in 18 Zimbabwean naturally fermented milk (amasi) samples and those produced by various yeasts, lactic acid bacteria (LAB) and yeast/ LAB combinations were determined using headspace gas chromatography. The yeast strains used were:
The effect of temperature on the growth of yeasts during the production of Sethemi, South African... more The effect of temperature on the growth of yeasts during the production of Sethemi, South African naturally fermented milk (NFM), was studied by incubating raw milk and milk inoculated with selected yeast strains at 7, 15, 25 and 37°C. The different temperatures were selected to represent the average ambient temperatures around Bloemfontein, South Africa, during winter, spring, summer, and in the human body, respectively. The yeast strains used had previously been isolated from Sethemi and identified as Kluyveromyces marxianus, Saccharomyces cerevisiae, Candida albicans and Debaryomyces hansenii. The yeast strains were inoculated into raw milk separately and also as a mixture of the four strains. The yeast counts, lactic acid bacteria counts and pH were monitored over a period of 20 days. It was observed that although all the yeast strains grew in the milk at all temperatures, the fastest growth was at 37°C but there was a prolonged lag phase at 7 and 15°C. The highest yeast counts of 8.30 log (CFU/mL) were obtained at 25°C in the milk inoculated with K. marxianus. At all temperatures, the initial yeast count in the control was significantly (p<0.05) lower than the counts in the inoculated milk. Lactic acid bacteria also grew to high numbers both with added yeast and in the control. The highest LAB counts of about 11.59 log (CFU/mL) were obtained in the presence of S. cerevisiae after about 4 days of incubation at 25°C. The addition of different yeast strains did not affect significantly the growth of LAB at all temperatures. After 3 days, the LAB counts decreased rapidly at 37°C, while from day 2 to day 5 the LAB numbers remained stable at 25°C. There was a rapid decrease in pH at higher temperatures than at 7 or 15°C, corresponding to the LAB growth. A temperature of 25°C was found to be ideal for producing fermented milk with high LAB counts, low pH and a visually acceptable coagulum.
Working with regulatory and enforcement authorities will help to create a more stable business en... more Working with regulatory and enforcement authorities will help to create a more stable business environment informal food vendors and encourage better working practices that will result in the sale of safer foods by the vendors. Two training workshops, each lasting 10 days, were organised for Lusaka and Harare, on 1-10 March 2004 and 22 March-1 April 2004, respectively. The training involved lectures, case studies, laboratory practical work and interactive group work. At the end of the training, participants were expected to understand what street vended (informally vended) foods are, the laws governing the sale of such foods, and the methods that can be used to improve the safety of the foods. The participants covered the following topics:
Ziziphus mauritiana (masau) fruits are consumed by many people in Zimbabwe. The fruits contribute... more Ziziphus mauritiana (masau) fruits are consumed by many people in Zimbabwe. The fruits contribute significantly to people's diet when they are in season. The objective of this study was to determine the nutritional content of the fruits and, hence, quantify their contribution to the diet. Samples of masau were collected in two seasons (August 2006 and August 2007). Both macronutrients and micronutrients were determined using standard AOAC methods of analysis. Dry matter content ranged from 21.1 ± 0.2 to 24.1 ± 0.3 g 100 g À1 of edible portion of the sweet and sour fruits, and 84.8 ± 0.2 to 87.2 ± 0.2 g 100 g À1 for the dried fruit. Crude protein per 100 g edible portion of dry weight ranged between 7.9 ± 0.0 and 8.7 ± 0.0 g, crude fat from 0.8 ± 0.0 to 1.5 ± 0.0 g, crude fibre from 4.9 ± 0.0 to 7.3 ± 0.0 g, ash between 3.0 ± 0.0 and 4.3 ± 0.0 g and carbohydrate between 79.5 ± 0.0 and 83.2 ± 0.0 g. The fruits were rich in vitamin C (15.0 ± 0.0-43.8 ± 0.02 mg 100 g À1 ) and the energy values ranged between 1516.0 ± 1.73 and 1575.0 ± 2.3 kJ 100 g À1 . Furthermore, the fruits contained (mg 100 g À1 of dry weight) potassium from 1865.0 ± 1.3 to 2441.0 ± 1.1, calcium from 160.0 ± 0.3 to 254.0 ± 0.1, sodium between 185.0 ± 0.1 and 223.0 ± 0.2, magnesium between 83.0 ± 0.0 and 150.0 ± 0.13 and phosphorous from 87.0 ± 0.1 to 148.0 ± 0.5. Manganese and copper contents ranged between 0.7 ± 0.03 and 1.6 ± 0.03, while iron and zinc ranged between 2.1 ± 0.43 and 4.3 ± 0.1, and 0.6 ± 0.0-0.9 ± 0.0 mg 100 g À1 of dry weight, respectively. The masau fruit is therefore a good potential source of carbohydrates, proteins and micronutrients, such as calcium, potassium, sodium, phosphorous, copper, iron, Vitamin C and zinc.
Masau are Zimbabwean wild fruits, which are usually eaten raw and/ or processed into products suc... more Masau are Zimbabwean wild fruits, which are usually eaten raw and/ or processed into products such as porridge, traditional cakes, mahewu and jam. Yeasts, yeast-like fungi, and lactic acid bacteria present on the unripe, ripe and dried fruits, and in the fermented masau fruits collected from Muzarabani district in Zimbabwe were isolated and identified using physiological and molecular methods. The predominant species were identified as Saccharomyces cerevisiae, Issatchenkia orientalis, Pichia fabianii and Aureobasidium pullulans. A. pullulans was the dominant species on the unripe fruits but was not isolated from the fermented fruit pulp. S. cerevisiae and I. orientalis were predominant in the fermented fruit pulp but were not detected in the unripe fruits. S. cerevisiae, I. orientalis, P. fabianii and S. fibuligera are fermentative yeasts and these might be used in the future development of starter cultures to produce better quality fermented products from masau fruit. Lactic acid bacteria were preliminary identified and the predominant strains found were Lactobacillus agilis and L. plantarum. Other species identified included L. bifermentans, L. minor, L. divergens, L. confusus, L. hilgardii, L. fructosus, L. fermentum and Streptococcus spp. Some of the strains of LAB could also potentially be used in a mixed-starter culture with yeasts and might contribute positively in the production of fermented masau fruit products.
Background: Fermentation is an age old technique of preserving food in many communities. A wide r... more Background: Fermentation is an age old technique of preserving food in many communities. A wide range of fermented products are prepared by varying the types of raw materials, utensils, and fermentation times. Several fermented foods are consumed in Swaziland. A survey of the types of fermented foods, preparation methods, and utensils used was done in the Hhohho region of Swaziland. The current study aimed at documenting the preparation methods of emahewu, emasi, umcombotsi, and buganu at household levels. Methods: Detailed fermentation steps were documented for umcombotsi, emahewu, buganu, and emasi. Five constituencies, called tinkhundla, were randomly selected from the 14 found in the Hhohho region of Swaziland. At each inkhundla, households that were known to regularly prepare the fermented foods were identified with the assistance of local community leaders and were interviewed. A semistructured questionnaire was used for the face-to-face interviews. Results: With respect to preparation procedures and practices, all respondents indicated that they had prepared different fermented foods at one time or another. The most commonly prepared and readily available fermented foods were umcombotsi (alcoholic beverage), emahewu (nonalcoholic beverage), buganu (marula wine), and emasi (spontaneously fermented milk). Both men and women indicated that they prepared umcombotsi, and only women reported that they prepared emahewu, buganu, and emasi. Umcombotsi was mainly prepared for sale, while buganu, emahewu, and emasi were for sale as well as for household consumption. Umcombotsi was mostly prepared by mixing maize meal, unmilled sorghum malt (magayiwe), and brown sugar (3 kg) in water (20 L). The initial stage involved cooking the mixture to gelatinize the starch, followed by fermentation at ambient temperature (25e30 C) for about 72 hours. The whole preparation process takes about 4e5 days. Emahewu was prepared by mixing maize meal (1 kg) with water (5 L) and cooking to make a soft porridge. The cooled porridge was left to ferment at room temperature. Some reported adding sugar or a peeled potato to aid the fermentation process. Emasi was prepared by letting raw milk to naturally ferment at room temperature (25e30 C) in either metal or plastic containers (buckets) for 2e3 days. Buganu was prepared from marula fruit (amaganu) juice and pulp mixed with water (10 L) and sugar (2 kg). The mixture was allowed to ferment at ambient temperature for about 3 days, sieved, and then served. Conclusion: Umcombotsi, emahewu, buganu, and emasi were the fermented foods commonly prepared at a household level in the Hhohho region, Swaziland. The main ingredient used for preparing umcombotsi and emahewu was maize meal. Unmilled sorghum malt was also added during preparation of umcombotsi. However, typically no malt was added during the preparation of emahewu. Buganu and emasi also play an important role in the diet and socioeconomic activities of the population in Swaziland.
Summary The effect of temperature on the growth of yeasts during the production of Sethemi, South... more Summary The effect of temperature on the growth of yeasts during the production of Sethemi, South African naturally fermented milk (NFM), was studied by incubating raw milk and milk inoculated with selected yeast strains at 7, 15, 25 and 37 °C. The different temperatures were selected to represent the average ambient temperatures around Bloemfontein, South Africa, during winter, spring, summer, and in the human body, respectively. The yeast strains used had previously been isolated from Sethemi and identified as Kluyveromyces marxianus, Saccharomyces cerevisiae, Candida albicans and Debaryomyces hansenii. The yeast strains were inoculated into raw milk separately and also as a mixture of the four strains. The yeast counts, lactic acid bacteria counts and pH were monitored over a period of 20 days. It was observed that although all the yeast strains grew in the milk at all temperatures, the fastest growth was at 37 °C but there was a prolonged lag phase at 7 and 15 °C. The highest ye...
Harnessing the freely available source of energy from the sun offers a number of additional benef... more Harnessing the freely available source of energy from the sun offers a number of additional benefits. Not least of these benefits is the fact that solar energy is an environmentally sustainable alternative. A four-wing compound parabolic concentrator (CPC) was designed as a modification of the regular non-imaging CPC concentrator that has a widespread use as solar collector. The design is intended to increase the angle of acceptance as well as concentration of energy from the sun. The conceptual design, mathematical formulation as well as construction and initial trial results have been presented in this paper. Pilot trials of the four-wing concentrator used for sanitizing both liquid and waste products produced satisfactory results. Improvements in terms of design as well as material used for construction and better preservation of heat can be considered further in the future research.
Food safety is a global issue, affecting food production and processing. The study assessed the m... more Food safety is a global issue, affecting food production and processing. The study assessed the microbiological quality of commercially dried fruits and home dried fruits and vegetables in Lesotho. Moisture content, pH and water activity of the fruits and vegetables were determined using standard methods. Nine different growth media were used for microbial evaluation. Moisture content and water activity were within World Health Organisation guidelines for dried fruits and vegetables. Fungi counts ranged from 2.0x10 2 to 8.7x10 5 CFU g-1 , and dried pumpkin leaves recorded the highest. More than 45% and 38% of the samples exceeded the fungal and total aerobic counts recommended by WHO, respectively. Possible pathogens of the genera Salmonella, Shigella, Bacillus and other Enterobacteriaceae were isolated from home dried samples. Faecal coliforms were detected in 55% of the home dried food products. More than 60% of the samples recorded higher microbial levels than recommended. While half of commercially dried fruits exceeded international standards, all home dried fruits and vegetables recorded unacceptably high levels of fungal contamination. The presence of possible pathogenic organisms in these foodstuffs suggest a potential public health hazard to consumers. Sanitation and personal hygiene, especially during home-based food processing, needs improvement.
Edible wild plants were investigated as potential sources of antioxidants and prebiotics to benef... more Edible wild plants were investigated as potential sources of antioxidants and prebiotics to benefit human health. Antioxidant activity, ascorbic acid and total dietary fibre contents were determined in edible wild plants from Lesotho, Swaziland and South Africa. Pure probiotic strains of Bifidobacterium animalis subsp. animalis (ATCC 25527), Lactobacillus rhamnosus (TUTBFD) and Lactobacillus acidophilus (ATCC 314) were cultured in broth containing edible wild plant extracts to assess their prebiotic activity. Cyperus esculantus had the highest arscobic acid content of 603±64.1 mg/100 g edible dry plant material followed by Rosa rubiginosa (500.8±48.8 mg/100 g). The two plants had IC50 of 10.7±0.2 µg/mL and 47.8±0.2 µg/mL for DPPH inhibition, respectively. Forty percent (40%) (n=30) of the edible wild plants had significant (p<0.01) total antioxidant activity (IC50<60 µg/mL) and high ascorbic acid content (>200 mg/100 g). Nasturtium officinale reported the highest yield for ...
International Journal of Food Microbiology, Sep 1, 2003
Yeasts are present in indigenous African fermented milks in numbers up to log 8 cfu g(-1), togeth... more Yeasts are present in indigenous African fermented milks in numbers up to log 8 cfu g(-1), together with a varied lactic acid bacteria (LAB) flora, and therefore potentially contribute to product characteristics. However, interaction between yeasts and LAB in these products has received little notice. In studies of indigenous fermented milk in Zimbabwe and Uganda, many samples contained more than one species of yeast, but Saccharomyces cerevisiae was most commonly isolated. Other frequent isolates were other species of Saccharomyces and several species of Candida. Most yeast isolates were lactose-negative but usually galactose-positive. Some strains assimilated lactate and citrate. The growth in milk of strains of yeasts and LAB, isolated from naturally soured milk in Zimbabwe, and their interaction when selected pairs of strains were grown together has been studied. Interactions were shown by the significantly different amounts of certain metabolites produced, such as acetaldehyde and malty aldehydes, when co-cultures were compared to pure cultures. Preliminary sensory acceptance tests did not show, however, that milks made from a co-culture with Candida kefyr and LAB were preferable to the pure LAB culture. Further work is still needed to elucidate the reactions that may be taking place in fermented milk between varying LAB and yeast populations. The potential for use as starter cultures depends on various aspects, including the final product being prepared. The role of other microorganisms in naturally fermented milk also needs to be studied.
The volatile organic compounds present in 18 Zimbabwean naturally fermented milk (amasi) samples ... more The volatile organic compounds present in 18 Zimbabwean naturally fermented milk (amasi) samples and those produced by various yeasts, lactic acid bacteria (LAB) and yeast/ LAB combinations were determined using headspace gas chromatography. The yeast strains used were:
The effect of temperature on the growth of yeasts during the production of Sethemi, South African... more The effect of temperature on the growth of yeasts during the production of Sethemi, South African naturally fermented milk (NFM), was studied by incubating raw milk and milk inoculated with selected yeast strains at 7, 15, 25 and 37°C. The different temperatures were selected to represent the average ambient temperatures around Bloemfontein, South Africa, during winter, spring, summer, and in the human body, respectively. The yeast strains used had previously been isolated from Sethemi and identified as Kluyveromyces marxianus, Saccharomyces cerevisiae, Candida albicans and Debaryomyces hansenii. The yeast strains were inoculated into raw milk separately and also as a mixture of the four strains. The yeast counts, lactic acid bacteria counts and pH were monitored over a period of 20 days. It was observed that although all the yeast strains grew in the milk at all temperatures, the fastest growth was at 37°C but there was a prolonged lag phase at 7 and 15°C. The highest yeast counts of 8.30 log (CFU/mL) were obtained at 25°C in the milk inoculated with K. marxianus. At all temperatures, the initial yeast count in the control was significantly (p<0.05) lower than the counts in the inoculated milk. Lactic acid bacteria also grew to high numbers both with added yeast and in the control. The highest LAB counts of about 11.59 log (CFU/mL) were obtained in the presence of S. cerevisiae after about 4 days of incubation at 25°C. The addition of different yeast strains did not affect significantly the growth of LAB at all temperatures. After 3 days, the LAB counts decreased rapidly at 37°C, while from day 2 to day 5 the LAB numbers remained stable at 25°C. There was a rapid decrease in pH at higher temperatures than at 7 or 15°C, corresponding to the LAB growth. A temperature of 25°C was found to be ideal for producing fermented milk with high LAB counts, low pH and a visually acceptable coagulum.
Working with regulatory and enforcement authorities will help to create a more stable business en... more Working with regulatory and enforcement authorities will help to create a more stable business environment informal food vendors and encourage better working practices that will result in the sale of safer foods by the vendors. Two training workshops, each lasting 10 days, were organised for Lusaka and Harare, on 1-10 March 2004 and 22 March-1 April 2004, respectively. The training involved lectures, case studies, laboratory practical work and interactive group work. At the end of the training, participants were expected to understand what street vended (informally vended) foods are, the laws governing the sale of such foods, and the methods that can be used to improve the safety of the foods. The participants covered the following topics:
Ziziphus mauritiana (masau) fruits are consumed by many people in Zimbabwe. The fruits contribute... more Ziziphus mauritiana (masau) fruits are consumed by many people in Zimbabwe. The fruits contribute significantly to people's diet when they are in season. The objective of this study was to determine the nutritional content of the fruits and, hence, quantify their contribution to the diet. Samples of masau were collected in two seasons (August 2006 and August 2007). Both macronutrients and micronutrients were determined using standard AOAC methods of analysis. Dry matter content ranged from 21.1 ± 0.2 to 24.1 ± 0.3 g 100 g À1 of edible portion of the sweet and sour fruits, and 84.8 ± 0.2 to 87.2 ± 0.2 g 100 g À1 for the dried fruit. Crude protein per 100 g edible portion of dry weight ranged between 7.9 ± 0.0 and 8.7 ± 0.0 g, crude fat from 0.8 ± 0.0 to 1.5 ± 0.0 g, crude fibre from 4.9 ± 0.0 to 7.3 ± 0.0 g, ash between 3.0 ± 0.0 and 4.3 ± 0.0 g and carbohydrate between 79.5 ± 0.0 and 83.2 ± 0.0 g. The fruits were rich in vitamin C (15.0 ± 0.0-43.8 ± 0.02 mg 100 g À1 ) and the energy values ranged between 1516.0 ± 1.73 and 1575.0 ± 2.3 kJ 100 g À1 . Furthermore, the fruits contained (mg 100 g À1 of dry weight) potassium from 1865.0 ± 1.3 to 2441.0 ± 1.1, calcium from 160.0 ± 0.3 to 254.0 ± 0.1, sodium between 185.0 ± 0.1 and 223.0 ± 0.2, magnesium between 83.0 ± 0.0 and 150.0 ± 0.13 and phosphorous from 87.0 ± 0.1 to 148.0 ± 0.5. Manganese and copper contents ranged between 0.7 ± 0.03 and 1.6 ± 0.03, while iron and zinc ranged between 2.1 ± 0.43 and 4.3 ± 0.1, and 0.6 ± 0.0-0.9 ± 0.0 mg 100 g À1 of dry weight, respectively. The masau fruit is therefore a good potential source of carbohydrates, proteins and micronutrients, such as calcium, potassium, sodium, phosphorous, copper, iron, Vitamin C and zinc.
Masau are Zimbabwean wild fruits, which are usually eaten raw and/ or processed into products suc... more Masau are Zimbabwean wild fruits, which are usually eaten raw and/ or processed into products such as porridge, traditional cakes, mahewu and jam. Yeasts, yeast-like fungi, and lactic acid bacteria present on the unripe, ripe and dried fruits, and in the fermented masau fruits collected from Muzarabani district in Zimbabwe were isolated and identified using physiological and molecular methods. The predominant species were identified as Saccharomyces cerevisiae, Issatchenkia orientalis, Pichia fabianii and Aureobasidium pullulans. A. pullulans was the dominant species on the unripe fruits but was not isolated from the fermented fruit pulp. S. cerevisiae and I. orientalis were predominant in the fermented fruit pulp but were not detected in the unripe fruits. S. cerevisiae, I. orientalis, P. fabianii and S. fibuligera are fermentative yeasts and these might be used in the future development of starter cultures to produce better quality fermented products from masau fruit. Lactic acid bacteria were preliminary identified and the predominant strains found were Lactobacillus agilis and L. plantarum. Other species identified included L. bifermentans, L. minor, L. divergens, L. confusus, L. hilgardii, L. fructosus, L. fermentum and Streptococcus spp. Some of the strains of LAB could also potentially be used in a mixed-starter culture with yeasts and might contribute positively in the production of fermented masau fruit products.
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