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Kaffee ist das wohl populärste Heißgetränk weltweit. Zwei botanische Arten sind für den Weltmarkt von Bedeutung und unterscheiden sich bezüglich ihres Anbaugebietes und der Inhaltsstoffe. Kaffee enthält über 850 bisher identifizierte Aromastoffe, welche den Geschmack bilden. Außerdem haben die Prozessierung der geernteten Kirsche bis zur Bohne, das Röstprofil und das Aufbrühen einen großen Einfluss darauf. In dieser Arbeit wurde die Auswirkung der Prozessierungsmethode auf ausgewählte Inhaltsstoffe mit Hilfe der Flüsssig-Chromatographie-Tandem-Massenspektroskopie (LC-MS/MS) untersucht. Dafür wurden drei Prozessierungsmethoden, die unterschiedlich viel Wasser für das Ablösen des Fruchtfleisches von den Kaffeekirschen benötigen, und zwei Kultursorten miteinander verglichen. Die Ergebnisse zeigten einen geringfügig höheren Gehalt der zwei wichtigsten Inhaltsstoffe Koffein und Chlorogensäure in den Bohnen, bei deren Prozessierung im Eco-Pulper-Verfahren weniger Wasser eingesetzt wurde. Bis auf einen verringerten Gehalt an Saccharose wurde für weitere wichtige Inhaltsstoffe (Acrylamid, Niacin, Zitronensäure und Vanillin) kein signifikanter Unterschied bei höherem Wassereinsatz gefunden. Insofern man die untersuchten Inhaltsstoffe als Qualitätsmarker betrachtet, ist im Vergleich zu den anderen Prozessierungsmethoden das Eco-Pulper-Verfahren die beste Wahl, insbesondere da es als wassersparende Methode einen entscheidenden Beitrag zur Nachhaltigkeit des Kaffeeanbaus leistet.

Yoghurt is a popular probiotic milk product. Coffee flavoured yoghurt was developed to enrich the product with functional properties and help enhance local coffee consumption. The aim of the research was to study potential interaction of polyphenolic compounds present in coffee extract on the viability of lactic acid bacteria, yeast and moulds and, functional properties of coffee flavored yoghurt. Coffee flavoured yoghurt was prepared by adding coffee flavour extract to the yoghurt in varying amounts; 0.0%, 0.1%, 0.2%, and 0.3%. Treatment 0.0% was the control. A complete randomized design (CRD) was used, in which yoghurt was divided into 4 treatments in triplicate and was randomly assigned to 12 experimental units. The sampling for analysis was done at intervals of one week for 28 days from day one. Microbial analysis was done using standard AOAC 2016 method using MRS and PDA media and results were reported as CFU/ml of the coffee flavored yoghurt. Functional properties were determined by evaluation of total polyphenols and antioxidant activity using the Free radical scavenging activity by DPPH method and Folin ciocateau method. Data was analyzed by use of ANOVA, means separated by LSD at p<0.05 level of significance. From the findings, lactic acid bacteria in coffee flavoured yoghurt ranged between 3.7x107-1.09x108CFU/ml. Yeast and moulds ranged between 3.6x101-8.33x100 CFU/ml. TPC between 5.76±0.4-97.89±0.6mgGAE/ml while Antioxidant properties ranged from 15.82±0.9- 68.55±0.9 % DPPH. There were significant differences between coffee flavoured yoghurt and the control on the functional properties. In conclusion, addition of coffee flavour extract into the yoghurt improved the keeping quality of the yoghurt while maintaining its probiotic potential. More studies on addition of natural coffee flavour into other milk products are recommended.

The chia seed samples were purchased from farmers in five locations in three agro-ecological zones in Kenya. The oil was obtained by cold pressing and physicochemical properties were determined; the fatty acid profile was determined by Gas chromatography. The mean oil yield from pressing was 16%, the refractive index of chia seed oil at 25 °C ranged from 1.4811 to 1.4832, specific gravity ranged from 0.9616 to 0.9629, acidity index and free fatty acids content ranged from 0.0345-0.0808 mg KOH/g oil, and 0.1736-0.4061%, respectively. The matter in volatiles ranged from 0.047-0.086%. The saponification value ranged from 162.1969–183.3791 milligrams (mg) of potassium hydroxide (KOH) per gram (g) of chia seed oil. The differences in refractive index, acidity index, free fatty acids, specific gravity, and saponification value, were statistically significant at (P<0.05). The α-linolenic (C18:3) and linoleic acids (C18:2) were the dominant fatty acids in chia seed oil and they varied with regions. The levels α-linolenic (C18:3) and linoleic acids (C18:2) ranged from 53.32-64.04% and 19.37-22.87%, respectively. The levels of oleic, linoleic, and linolenic fatty acids in chia seed oils from different regions were statistically significant at (P<0.05). The study recommended the cultivation of chia seed in agro-ecological zones II and III where higher yields and higher content of linoleic and linolenic fatty acids were reported, consumption of chia seed oil as edible oil, and substitution of marine oils with chia oil as potential sources of polyunsaturated fatty acids.