Production, microbiological and quality evaluation of low-fat spiced yoghurts with low glycemic loads

Spiced yoghurt improves health in various ways such as ability to improve metabolism and burn extra calories. Consumption of full fat yoghurt has declined due to the awareness of the probable harmful effects of fat on consumers’ health, thus dietary habits of consumers have changed and market interest has also tended to change in favour of low or non-fat yoghurt. This study was aimed at highlighting the physico-chemical, microbiological analysis and nutritional importance of spiced yoghurts. Standard methods were used for the production of plain and spice -treated yoghurts and the spices used were turmeric, Aframomum danielli and clove (1% w/v), respectively. All the yoghurt samples were stored at 4°C.Control sample (plain yoghurt) had no spice. Physicochemical profile, proximate composition and microbiological analysis were determined for all the yoghurt samples. The glycemic load of each sample was calculated by multiplying the glycemic indices (GIs) of non-fat yoghurt (International Glycemic Index Table) by the available carbohydrate and dividing the product by 100. While the carbohydrate content of plain yoghurt was 24.15 ± 0.69%, turmeric and Aframomum danielli- spiced yoghurts had 14.75 ± 0.69 %and 14.37 ± 1.29%, respectively. The fat contents of plain, turmeric, Aframomum danielli and clove spiced - yoghurts were 0.10±0.05%, 0.03±0.01%, 0.20±0.13% and 0.25±0.63%, respectively. The spiced yoghurts had decreased pH and increased titratable acidity values during the storage period. Total bacterial counts of turmeric (1.4×104 cfu/ml), Aframomum danielli (1.0×104 cfu/ml) and clove (1.6×104 cfu/ml) spiced yoghurts decreased when compared to plain yoghurt with 2.4×104 cfu/ml. Some fungi were detected in spiced yoghurts toward the end of storage period. The results of GIs obtained were found to be under low glycemic load. Glycemic load of plain yoghurt (7.86± 0.24) was significantly (P ≤ 0.05) higher than those of clove (4.56 ± 0.45) and Aframomum danielli (4.64 ±0.43) spiced yoghurts, respectively. In conclusion, spiced yoghurt is a nutritionally beneficial product which is considered to be safe. The findings of the present work can be useful from the standpoint of health of yoghurt consumers.Keywords: Spice, yoghurt, glycemic load, quality evaluation, Aframomum danielli, turmeric, clov

Hydro geophysical Investigation for groundwater development at Gbongudu Area, Akobo Ojurin, Ibadan, Southwestern Nigeria

This paper presents the geophysical investigation for groundwater at Gbongudu area, Akobo Ojurin, Ibadan, Southwestern Nigeria. The area is underlain by the crystalline basement complex rocks and accessibility to potable water especially in the dry period of the year has been a major challenge. The Vertical Electrical Sounding using the Schlumberger configuration was employed. Twelve (12) vertical electrical sounding points were established in order to delineate the geo-electric layers in the area as well as evaluate the groundwater potential. The results are presented as profiles, geologic sections, curves, and maps. The VES results revealed a maximum of five geo-electric layers, viz: topsoil/lateritic sand, shale/clay, weathered layer, fractured basement and fresh basement respectively. Geo-electric sounding results were critically analyzed and interpreted. The yields of wells dug in most of these locations may be insufficient, even for domestic use because of its relatively small thicknesses. However, at a depth of 9.1 m a fracture zone occurs in VES 6 with resistivity value of 17.8 Ωm suggesting the presence of groundwater. Groundwater potential in this area is low on the average with VES 6 and VES 7 considered to be the main aquifer units suitable for groundwater exploration.Keywords: basement complex, electrical sounding, groundwater, exploration, aquifer

Case report: Spontaneous staphylococcal arthritis in athymic SPF mice

Six cases of spontaneous purulent arthritis confined to the hock joints in male Han-NMRI-nu/nu mice have been observed in a SPF colony. Bacteriological examination revealed a protein A-positive Staphylococcus aureus belonging to phagegroup II. results of the histological, bacteriological examinations and the importance of S. aureus of the 3A/3C/55/71 phage complex for small laboratory animal are discussed

Chemical composition and acceptability of yam flour supplemented with whole wheat and soy flour

Objective: The study was conducted to determine chemical composition of yam flour substituted with soy and whole wheat flour and acceptability of 'amala' prepared from the yam flour blends.Materials and methods: The yam flour was prepared using conventional method adopted from traditional method of yam flour production. The blend of yam, whole-wheat and soy flour was done in the ratio 30:60:10, 60:30:10, 45:45:10 and coded as A, B and C respectively. These blends were used in preparing 'amala' and compared with pure non-substituted yam and whole wheat flour: D and E respectively which served as control samples. Chemical composition of the yam flour blends and acceptability of 'amala' prepared from them were evaluated.Results: Sensory evaluation indicated that 'amala' made from the blend of A was acceptable to consumers but there was preference for 'amala' from B blend in terms of smoothness, texture, color, taste and flavor. There was increase in the fat content (1.3% -2.5%) of the substituted yam flour blends. Protein content for the substituted yam blends ranged between 11.10-12.61% compared to 1.29% and 10.71% in yam flour and wheat flour respectively. There was also significant reduction (p< 0.05) in carbohydrate, starch and moisture contents of the substituted yam flour blends but the fiber contents were not significantly affected.Conclusion: Substitution of yam flour with soy and whole wheat flour improved the nutritive value of 'amala'. The preferred blend, sample B, had low moisture content, high protein, ash and fiber.Keywords: Yam flour, Soybean, whole wheat flour, substituted yam flou

Enumeration of the microbiota and microbial metabolites in processed cassava products from Madagascar and Tanzania

Published online: 19 Dec 2018Cassava processing practices vary among communities and countries with implications for food safety. The study examined the microbiota and microbial metabolite profiles of 126 samples of sun-dried cassava products: grits, improved chips, improved flour, kivunde, and makopa from Tanzania, and mangahazo maina from Madagascar. All samples were free of Salmonella spp. Only 12.5% makopa, 6.7% of mechanically processed flour, and 25% of chips conformed to yeast/mold regulatory limits (103 cfu/g). Among the most agriculturally important mycotoxins, aflatoxins (B1, B2, G1, and M1) were detected in 6.3–11.9%, fumonisins (B1, B2 and B3) in 3.2–41.3%, and zearalenone in 41.3% of the samples. A few samples of improved chips, improved flour, and makopa contained high aflatoxin B1 content. Some emerging mycotoxins: emodin, beauvericin, moniliformin, sterigmatocystin, alternariol methyl ether, nivalenol, mycophenolic acid, enniatin B, and enniatin B1 were detected. The most prevalent microbial metabolites were emodin (75.4%), tryptophol (67.5%), equisetin (61.9%), and beauvericin (51.6%), at mean concentrations of 8.8 μg/kg, 794.1 μg/kg, 277.2 μg/kg, and 29.5 μg/kg, respectively. Emodin and Beauvericin are the only emerging mycotoxins in this group and the mean concentrations are the lowest. Nevertheless, regular surveillance along the cassava food chain is recommended for early detection of emerging mycotoxins to prevent health problems associated with ingestion of unexpected toxins in foods

The combined action of carvacrol and high hydrostatic pressure on Listeria monocytogenes Scott A

Aims: The aim of the study was to investigate the combined antimicrobial action of the plantderived volatile carvacrol and high hydrostatic pressure (HHP). Methods and Results: Combined treatments of carvacrol and HHP have been studied at different temperatures, using exponentially growing cells of Listeria monocytogenes, and showed a synergistic action. The antimicrobial effects were higher at 1°C than at 8 or 20°C. Furthermore, addition of carvacrol to cells exposed to sublethal HHP treatment caused similar reductions in viable numbers as simultaneous treatment with carvacrol and HHP. Synergism was also observed between carvacrol and HHP in semi-skimmed milk that was artifcially contaminated with L. monocytogenes. Conclusions: Carvacrol and HHP act synergistically and the antimicrobial effects of the combined treatment are greater at lower temperatures. Significance and Impact of the Study: The study demonstrates the synergistic antimicrobial effect of essential oils in combination with HHP and indicates the potential of these combined treatments in food processing