Physicochemical properties and sensory quality of Motlopi (Boscia albitrunca) coffee prepared using different temperature-time combinations.

Motlopi coffee is a beverage prepared from roots of an indigenous tree Boscia albitrunca and consumed in Botswana. To date, there is no published report about the quality characteristics of Motlopi coffee. This study was conducted to develop an improved Motlopi coffee by varying roasting time and temperature and assess its physicochemical properties and sensory quality. The roasting temperatures considered were 150 °C and 160 °C with roasting time of 10, 15 and 20 min at each temperature. The study showed that bulk density of ground coffee was significantly (p < 0.05) decreased at 160 °C than at 150 °C and pH of Motlopi coffee was generally higher at 150 °C than at 160 °C. The total soluble solids (TSS) of Motlopi coffee decreased with increasing roasting time at 150 °C; however, it increased with increase in roasting time at 160 °C. Browning index (BI) tended to increase with increase in roasting time both at 150 and 160 °C and was significantly (p < 0.05) higher at 160 °C than at 150 °C. The titratable acidity (TA) decreased with an increase in the roasting time both at 150 and 160 °C and was significantly (p < 0.05) higher at 150 °C than at 160 °C. The traditionally prepared Motlopi coffee had comparable TA with treatment 2 (150 °C for 15 min). The consumer acceptability test showed that the laboratory made Motlopi coffee had significantly higher (p < 0.05) scores for taste, body and overall acceptability than the traditional Motlopi coffee. Roasting Motlopi roots at 150 °C for 15 min resulted in Motlopi coffee of good physicochemical properties and sensory quality.

Metagenomic analysis of bacterial community composition in Dhanaan: Ethiopian traditional fermented camel milk.

This study was conducted to evaluate the safety and bacterial profile of Dhanaan (Ethiopian traditional fermented camel milk). The composition of the microbial community in Dhanaan samples was analysed by a metagenomic approach of 16S rRNA gene amplicon sequencing. Metagenomic profiling identified 87 different bacterial microorganisms (OTUs) in six samples analysed. Although the Dhanaan samples contained various lactic acid bacteria (LAB), they also all contained undesirable microorganisms in large proportions. The following LAB genera were identified: Streptococcus, Lactococcus and Weissella. One Streptococcus species represented by OTU-1 (operational taxonomic unit) was found in all Dhanaan samples and the dominating species in four out of six samples. This common isolate was found to be closely related to S. lutetiensis and S. infantarius. Undesirable microorganisms from genera such as Escherichia, Klebsiella, Enterobacter, Acinetobacter and Clostridium were, however, also frequent, or even dominant in Dhanaan samples. Thus, this calls for a change in the Dahnaan manufacturing practice to an improved and safer production system. Starter cultures suitable for Dhanaan production might be developed from the Streptococcus, Weissella and Lactococcus microorganisms identified in this study. However, further safety evaluation and technological characterization need to be conducted on strains defined by OTU-1, OTU-2, OTU-3, OTU-8 and OTU-35 before they can be used as food grade starter cultures.

Processing Challenges and Opportunities of Camel Dairy Products.

A review on the challenges and opportunities of processing camel milk into dairy products is provided with an objective of exploring the challenges of processing and assessing the opportunities for developing functional products from camel milk. The gross composition of camel milk is similar to bovine milk. Nonetheless, the relative composition, distribution, and the molecular structure of the milk components are reported to be different. Consequently, manufacturing of camel dairy products such as cheese, yoghurt, or butter using the same technology as for dairy products from bovine milk can result in processing difficulties and products of inferior quality. However, scientific evidence points to the possibility of transforming camel milk into products by optimization of the processing parameters. Additionally, camel milk has traditionally been used for its medicinal values and recent scientific studies confirm that it is a rich source of bioactive, antimicrobial, and antioxidant substances. The current literature concerning product design and functional potential of camel milk is fragmented in terms of time, place, and depth of the research. Therefore, it is essential to understand the fundamental features of camel milk and initiate detailed multidisciplinary research to fully explore and utilize its functional and technological properties.

Functional and technological properties of camel milk proteins: a review.

This review summarises current knowledge on camel milk proteins, with focus on significant peculiarities in protein composition and molecular properties. Camel milk is traditionally consumed as a fresh or naturally fermented product. Within the last couple of years, an increasing quantity is being processed in dairy plants, and a number of consumer products have been marketed. A better understanding of the technological and functional properties, as required for product improvement, has been gained in the past years. Absence of the whey protein ß-LG and a low proportion of к-casein cause differences in relation to dairy processing. In addition to the technological properties, there are also implications for human nutrition and camel milk proteins are of interest for applications in infant foods, for food preservation and in functional foods. Proposed health benefits include inhibition of the angiotensin converting enzyme, antimicrobial and antioxidant properties as well as an antidiabetogenic effect. Detailed investigations on foaming, gelation and solubility as well as technological consequences of processing should be investigated further for the improvement of camel milk utilisation in the near future.

Effect of inclusion of tossign (Thymus serrulatus) in concentrate mix supplementation on performance and sensory quality of meat of Menz sheep.

The experiment was conducted to determine feed intake, digestibility, body weight change, carcass characteristics, and sensory quality of meat of Menz sheep supplemented with a concentrate mix and combinations of different proportions of tossign (Thymus serrulatus). Twenty yearling intact male Menz sheep were divided according to their initial body weight into five blocks of four animals in a randomized block design, and treatments were assigned randomly to each sheep within each block. The treatments were a basal diet of hay alone (T1) and supplemented with 300 g concentrate mix (T2), 200 g concentrate mix + 100 g tossign (T3), and 100 g concentrate mix + 200 g tossign (T4) on a dry matter basis. The results indicated that supplementation of tossign together with concentrate mix significantly increased (P < 0.001) feed intake and improved DM and nutrient digestibility compared to the non-supplemented group. Supplementation of tossign with concentrate significantly improved (P < 0.001) daily weight gain, feed conversion efficiency, and carcass characteristics of sheep compared to the non-supplemented group. Flavor and aroma scores of meat samples of sheep in T3 and T4 were significantly higher (P < 0.001) than the corresponding values in T1 and T2. The scores for tenderness, juiciness, and degree of marbling of meat samples of sheep were significantly higher (P < 0.001) in T3 and T4 compared to meat samples of sheep in T1. Inclusion of small amounts of tossign as additive in concentrate mix supplementation can improve the sensory quality of meat of Menz sheep.