3.3. Apparent viscosity
The apparent viscosity variations of ice cream mixes at different rotational speeds are shown in Figure 2. What is evident in all curves viscosity is generally decreased by a velocity of 10 to 100 rpm, and at higher speeds, the slope of the changes has been lowered and has become more stable. This represents the non-Newtonian behavior (pseudoplastic) of the ice cream mixes. [3] Goff and Hartel [3] consider non-Newtonian ice cream behavior as a result of dispersion of protein macromolecules and polysaccharides. Marshal and Ar-buckle (1996) argued that the accumulation of fat globules is leads to the weakness of the ice cream mix because during the rotation the fracture accumulation structure is weakened (Marshal and
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Significant differences were observed in all samples except for LFI1 and LFI3 treatments (p<0.05). CMFFI and LFI2 mixes respectively were the most viscous and CLFI mix was the least viscous (p<0.05).Results show that increasing the amount of fat alone in control treatments (CLFI, CRFI, CFFI and CMFFI), and thus increasing the TS, can cause an increase in their apparent viscosity; because the quantity of fat and type of milk used in this study are different and other factors were the same. Some researchers reported apparent viscosity of ice cream mix samples with a fat content of 5 and 10 percent which were significantly higher than the viscosity of samples with a fat content of 0.5 and 2.5 percent. According to Marshal and Arbuckle (1996), the increase in the aggregated fat globules in these ice creams was partly responsible for thinning the shear rate and hence their higher viscosity. On this basis, they the suggested the low viscosity of a nonfat sample probably due to the lack of fat globules in its formulation. (Aime et al., …show more content…
The positive effect of TSM on the viscosity of nonfat yogurt in the level of 30% due to its higher viscosity than skim milk has been reported by previous researchers (Nouri et al., 2011). Some researchers have reported changes in the volume and shape of caseins and water retention in the weak network resulting from partial accumulation as factors in increasing the viscosity of the low-fat ice cream mix containing the chymosin enzyme (Chang et al., 1995).
The viscosity of LFI2 sample is greater than that of LFI3 sample (82.8%) while both have the same fat and different TSM, so it is likely that in order to achieve higher viscosity, a certain amount of aggregate of micelles is required .Chang et al., (1995) reported that using 33% more of the chymosin enzyme gives double as much apparent viscosity of ice cream mix.
There is no significant difference between the viscosity of LFI1 and LFI3 treatments, which shows that the viscosity obtained from the higher consumption of TSM is equal to the viscosity obtained from the increase of VF
However, once it reaches 70% of concentration, the enzyme becomes saturated, meaning that there are no active sites for the substrates to fill, which leaves casein (milk) molecules suspended in the curd; the saturation point for this curve was located at 6.5x 10-3 seconds. This was clearly evident in some of the visual results of the practical, where we could see that there was still milk that could be decanted when the curd was poured out. Therefore, even if we added more casein substrate, the curve enzyme activity would still flatten, indicating again that all or most of the active sites of the renin enzyme were full.
Everyone is looking for better and healthier life! People today pay more and more attention to the food they eat, they want it to be healthy and tasty, on the other side modern life is so dynamic and eventful, that the food must be fast. So you need to come up with something that will support all these needs. The great solution is Frozen Yogurt. It is a refreshing, savory dessert that combines the flavors and textures of ice cream and sherbet. Frozen yogurt is a new-comer in the dessert market. Nevertheless, “the history of frozen desserts dates back thousands of years to Asia where water ices were first made.’’ (wiki) Yogurt was brought to the U.S. in the early 1900s and steadily increased in popularity as a health food item over the next several decades. By the 1970s, with the popularity of ice cream technology was transferred to the production of frozen yogurt. But it’s entry into the dessert market was a distinct failure—consumers complained that it tasted too much like yogurt. Relaying on consumer demand for a sweet product that tasted like ice cream, TCBY opened its first store in 1981. The highest popularity comes to Fro-yo by the mid 1990s. But in the late 1990s as Americans turned their attention to high-protein, high-fat diets, demand for frozen yogurt slowed considerably. Low-fat foods such as frozen yogurt fell out of favor as food trends preferred higher fat and lower cost ice cream at the turn of the millennium. Trends changed back to frozen yogurt in the mid 2000s with the advent of live probiotic powder-based mixes. Over the last decade the production of frozen yogurt has grown multi-million dollar business with dozens of competing companies.
In The “So Called Iced-Cream” by Daniel Barwick and “How Not to Get Into College: The Preoccupation with Preparation” by Alfie Kohn both demonstrate that life is meaningless without having passion for the things you do and things you wish to achieve in life. First of all, from Barwick’s essay Monty Burns has everything in gross excess yet cannot bring joy into his life. For instance, the narrator writes, “How could it be that Mr. Bums is unhappy? He has his own Xanadu, a nuclear power plant that he runs with his iron fist, a chauffeur driven Rolls-Royce, control over the local Republican Party… He was even reunited with his precarious teddy bear, Bobo. What, then, might the problem be? (Barwick, 3) Despite
However, low HLB surfactants may also be an important component of oral lipid-based formulation by behaving as a coupling agent for the high HLB surfactants and the lipophilic solvent components, as well as contributing to solubilization by remaining associated with the lipophilic solvent post-dispersion. Moreover, using a blend of high and low HLB surfactants may also lead to more rapid dispersion and finer emulsion droplet size upon addition to an aqueous phase [36, 48, 49, 51–55]. Thus, in this study, we decided to mix Tween 80 (high HLB value) with Carbitol (low HLB value) to identify the most effective combination emulsifying with three chosen oils. The size of the emulsion droplets decreased as the HLB value of surfactant mixture reached the required HLB (Table 2). In the case of soybean oil, the smallest size was 277 ± 2.49 nm obtained at 20:80 (v/v) ratio of Tween 80:Carbitol). In the cases of ethyl oleate (Tween 80:Carbitol, 90:10, v/v) and IPM (Tween 80:Carbitol, 60:40), the smallest droplet sizes were 2.9 ± 0.170 and 10.5 ± 0.596 nm, respectively. These results show that the combination of Tween 80 and Carbitol had extremely good emulsifying ability, resulting in a fine emulsion in the cases of using ethyl oleate and IPM oil. The results of the visual test (Fig. 1) are parallel to the results of droplet size measurements. The combinations that had a smaller droplet size of 100
Investigation into the Digestion of Milk by Trypsin Background Knowledge = == == == ==
The viscosity of the corn syrup, measured in seconds it takes for an iron ball to move downwards in the fluid.
The purpose of this lab was to determine which type of pineapple will allow gelatin to form through chemical reactions. There were two pineapple types were fresh and canned, each having their own distinct effects on the Jell-O mixture. The hypothesis stated that if the tinned pineapple is added to the gelatin mixture the solution will turn into a solid (Jelly). This is because when the tinned pineapple is preheated to remove microorganism the bromelain enzymes are destroyed since they do not have the ability to withstand high temperatures such as 100 degrees Celsius. When the protease found in pineapple becomes impractical gelatin can be formed when hot water is added to collagen. Based on the results and observations, it can be confirmed that
The kinematic viscosity is the ratio of viscosity ƞ to density ρ (taken at the same temperature and pressure).
If the amount of lactase is higher in plain yogurt, than the amount of glucose will also increase because lactase is an enzyme that breaks up the milk sugar lactose to produce the sugar glucose. If more lactase is present in a substance, such as the plain yogurt, than it will be easier and more efficient to break down the lactose into glucose. Therefore, if higher levels of lactase are present, then there will be more glucose present.
In order to identify the presence of lipids in these samples, we use the Sudan IV solution. If the unknown A, B, C milk samples turn from clear to dark pink color
Wagner, C. L., Anderson, D. M., & Pittard III, W. B. (June 1996). Special properties of human milk. Clinical Pediatrics , p 283.
Our brand has been at the forefront of setting the pace for the Ice cream industry. We came into the business not just to revolutionize the way it is done but to make a huge difference. The Gelato brand is striving to become the leading model for all businesses in our industry. It may interest you to know that our goal is to make Gelato – ice cream – frozen desserts, a synonymous part of your daily life. We have created a channel that would keep giving us the impetus to cover much ground. People do not forget the rich experiences they have when they enjoy unique Ice Cream. We are the Company that would keep giving everyone unique experiences.
Solid fat content of a fat and oil decides its applications and usages. The ratio of the solid phase to the liquid phase is main criteria when considering the functionality of the fat and oil in wheat dough. Empirical measure of SFC is Solid Fat Index (SFI) which is the ratio of solid fat to the total fat. SFI determines the functional performance and textural quality of fats and fat containing products (Lai and Lin, 2006). It impacts the spreadability of a fat. According to Richard (1968), creaming characteristics are traceable to the composition of the solid portions of the shortenings. The cookie produced with fat and oil having higher solid fat content had higher breaking force. The liquid component of the fat and oil delivers good lubricating function which improves the mixing process and solid component of the fats and oils entraps air bubbles during mixing. With efficient mixing, more
“Cream of Ice” as it was referred to back in the 17th century, was a similar dessert that was introduced to France in 1553 by Catherine de Medici. Ice cream was not available to the universal public till 1660. “A kind of ice-cream was invented in China about 200 BC, when a milk and rice mixture was frozen by packing it into snow.” (CBBC Newsround) Different types of ice cream can take different amounts of times to freeze, so the purpose of this experiment is to find out if different amounts of salt affect ice creams freezing time. This would help many ice cream businesses if they would need to add more salt or decrease the salt in their ice cream recipes.
ice cream belonging to the premium category. Based on our analysis, we have identified two major