Penetration and breakup characteristics of a discrete liquid jet injected into a high-velocity cross flowing airstream were investigated as a basis of plain-jet airblast atomizer design. The main variables covered in this phase were, airstream velocity (from about 35 to 150 m/s), liquid jet velocity (from about 5 to 25 m/s) and injection orifice diameter (from about 0.5 to 2.5 mm). The tests were conducted under conditions of normal atmospheric pressure and temperature using still photography for penetration profile and a laser light scattering technique for mean dropsize determination. The experimental penetration data is shown to agree, reasonably accurately, with a relatively simple model developed in the paper. The analysis of the experimental breakup data reveals the airstream velocity as exercising the strongest influence upon Sauter Mean Diameter.

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Low-fat frozen yoghurt was made by using commercial probiotic (Lactobacillus acidophilus, Streptococcus thermophilus & bifidobacteria) and traditional (Lactobacillus delbrueckii ssp. bulgaricus & Streptococcus thermophilus) starters; as well as; roasted red sweet potato and pumpkin for enhancing nutritional and functional values of this products. The preparing mixes and resulting frozen yoghurt stored at-20ºC for 8 weeks were evaluated for physicochemical, bacteriological and organoleptic properties. The results revealed that, there was significant differences (p<0.05) in all properties studied among the mixes and resulting frozen yoghurt. Frozen yoghurt mixes made with traditional yoghurt starter and sweet potato had higher specific gravity, weight per gallon, freezing point and apparent viscosity, but lower in pH values than the mixes made with probiotic starter. Also, resulting frozen yoghurt prepared with traditional starter and sweet potato had higher specific gravity, weight per gallon, freezing time, melting resistance and acetaldehyde content, but lower in overrun % and diacetyl content than that made with probiotic starter. Counts of Lb. delbrueckii ssp. bulgaricus, Str. thermophilus (traditional starter) and Lb. acidophilus were the most numerous in pumpkin frozen yoghurt, followed by sweet potato frozen yoghurt. On the other hand, sweet potato frozen yoghurt had higher Str. thermophilus & bifidobacteria (probiotic starter) counts, than the other treatments. However, frozen storage for 8 wk was slightly effected on the viable bacterial counts determined of different frozen yoghurt treatments, and bifidobacteria counts were still higher along the storage period than the recommended minimum levels. Also, frozen yoghurt manufactured with probiotic starter; especially with sweet potato; had the highest total organoleptic scores. Therefore, low-fat frozen yoghurt with improved nutritional and functional values, and also good organoleptic properties could be made by traditional yoghurt and probiotic starters; as well as roasted red sweet potato and pumpkin.

The effect of incorporating accustomed edible mushroom (Agaricus campestris) into processed cheese spread (PCSs) on the chemical, microbiological and organoleptic properties was evaluated. Tiny pieces of mushroom accustomed with steeping into citric acid and boiling in emulsifying salt solution were added to the blend of the cheese spread base at the levels of 5,10 and 15 %. The resulting PCSs were stored at 7°C for 3 months. Significant differences (p < 0.05) were recorded among the chemical composition of PCSs made without and with addition of mushroom. The incorporation of mushroom into PCSs resulted in higher contents of total solids, total protein, SN, ash, total carbohydrates and fiber, as well as pH values than the control spread. On the other hand, control treatment made without mushroom possessed the highest content in F/DM. Addition of mushroom to the base blend did not significantly affect (p > 0.05) in the salt and TVFA contents. The standard plate and psychrotrophic counts of PCSs made without and with mushroom showed slight differences when fresh and during the storage period. The standard plate counts slightly increased during the storage period reaching the maximum counts after one month, and then decreased with prolonged storage. Psychrotrophic bacteria gradually increased in all treatments throughout the storage period. On the other hand, no colonies were found from yeasts and molds, coliform and mesophilic anaerobic spores in all samples examined. Obvious differences (p < 0.05) were noticed in the organoleptic evaluation scores among all treatments of PCSs. The flavours of PCSs with mushroom were generally better and preferable when fresh and throughout the storage period. Addition of 15 % mushroom caused an over pieces of mushroom, which defected the body & texture and appearance & colour of the resulting spread. Therefore, PCSs with improved nutritional and functional values as well as acceptable organoleptic properties and good microbiological quality could be made by incorporation of accustomed edible mushroom into the base blend at the levels of 5 and 10% with refrigerated expiry period more than 3 months.

The healthy benefits of orange colored persimmons (Diospyros kaki L.) are highly related to their rich contents of total, soluble; and insoluble dietary fibers, total phenols, vitamin A, and C, and some minerals. The aim of this work was to verify the possibility of using persimmons as a natural function food agent in fruit ice cream manufacture. The fresh and boiled persimmons were added at levels of 5, 10, and 15% of ice cream mix. Changes in density, freezing point, viscosity, weight per gallon, titratable acidity, protein stability of ice cream mix as well as the overrun, melting resistance and sensory evaluation of the resultant ice cream were investigated. The obtained results revealed that the increase of the persimmons levels increased the acidity (%), specific gravity, weight per gallon in ice cream mix, as well as the decrease in the freezing point and protein stability of the mix. The overrun of ice cream decreased by the increase of the added persimmons. In general, both of melting resistances and specific gravity were increased by adding kaki fruit in ice cream mixes. From the data obtained, it could be recommended that ice cream can be produced with higher quality by adding 10%of persimmons in ice cream mix.