Physicochemical and Sensory Properties of Traditionally and Laboratory Made Ghee (Samin) of the Sudan
Samin is traditional cooking o il produced using the butter made fro m the milk of sheep , cow or goats.The objectives of the study was the determination of the physical, chemical and sensory characteristics of samin samp les collected fro m local market, preparation of Samin at the laboratory level and evaluation its quality. The mo isture content, acid value (mgKOH/g) , free fatty acids and peroxide value ranged 0.03 ±0.05% - 0.34+0.05%, 0.56 ± 0.0, - 1.94±0.17 (mgKOH/g), 0.28, -0.97±0.09%, 9.93 ± 0.23 - 2.60 ± 0.40 (mEq/kg) in the various samin samp les. However, the saponification value, density, viscosity, melt ing point and refract ive index of the different samin samples ranged 165.50-172.23(mgKOH/g), 0.925-913 g/cm³,0.519×10−3-0.335×10−3±0.02 pa.s, 38-37 Ċ and 1.4600-1.4582, respectively. The sensory evaluation revealed there was no-significant difference in texture, color, and overall acceptability of the samples, but there was significant difference (p ≤ 0.05) in flavour, between LM S sample and the other samples. It is highly reco mmended to imp rove production of samin under controlled hygienic conditions.
The Role and the Place of High-Performance Liquid Chromatography for the Determination of Fermented Dairy Products
Abstract Milk has been used to produce fermented milk products all over the world since 10,000 BC. The fermentation process extends the shelf life of milk-based products. Transforming milk to different fermented foods (kefir, yogurt, etc.) involves adding lactic-acid-producing microorganisms, which ingest lactose and release waste organic acids. Organic acid refers to organic compounds that give a characteristic quality to foods as a result of hydrolysis and microbial activity of proteins and carbohydrates that have been widely used as food additives to prevent deterioration and extend shelf life. Determination of carbohydrates and organic acids in dairy fermented products is important, since they affect the characteristics of food. It is also important to determine bacterial activity, as well as the growth of the colonies. An early investigation of fermented products based on titration methods that are not selective. Otherwise these methods are not sufficient to detect low concentration of acids. To avoid these difficulties, separation techniques, such as high-performance liquid chromatography (HPLC), and gas chromatography (GC), electrodriven techniques like capillary electrophoresis (CE), and so forth, were chosen due to accurate, selective, and sensitive analysis. In this chapter, the place and the importance of separation techniques, especially HPLC for the determination of dairy products, are explained briefly and the published papers on analysis conditions, the sample preparation, and the parameters for validation are summarized.
A comparative study of fatty acid profiles of Passiflora seed oils from Uganda
A comparative study is presented of the FA composition (FAC) of the seed oils from the yellow passion fruit Passiflora edulis Sims var. flavicarpa (I), the purple fruit Passiflora edulis Sims var. edulis (II), the purple Kawanda hybrid, which is a cross between I and II (III), and the light-yellow apple passion fruit Passiflora maliformis L. (IV) grown in Uganda. Oil yields from the four varieties were between 18.5 and 28.3%. A GC analysis of the oils showed the most dominant FA to be linoleic (67.8–74.3%), oleic (13.6–16.9%), palmitic (8.8–11.0%), stearic (2.2–3.1%), and α-linolenic (0.3–0.4%) acids. The unsaturated FA content in the oils was high (85.4–88.6%). Iodine values of the seed oils of I, II, III, and IV calculated from the FAC were 133, 141, 133, and 138, respectively. The FAC and the iodine value of the seed oil in III are distinctly closer to the rootstock (I) than the scion (II). This indicates that the rootstock influence on the FAC of passion fruit seeds is graft-transmissible. The study further confirms that passion fruit seed oils represent a good source of essential unsaturated FA.