Development of a healthy biscuit: an alternative approach to biscuit manufacture

Objective

Foods with contrasting glycemic index when incorporated into a meal, are able to differentially modify glycemia and insulinemia. However, little is known about whether this is dependent on the size of the meal. The purposes of this study were: i) to determine if the differential impact on blood glucose and insulin responses induced by contrasting GI foods is similar when provided in meals of different sizes, and; ii) to determine the relationship between the total meal glycemic load and the observed serum glucose and insulin responses.

Methods

Twelve obese women (BMI 33.7 ± 2.4 kg/m²) were recruited. Subjects received 4 different meals in random order. Two meals had a low glycemic index (40–43%) and two had a high-glycemic index (86–91%). Both meal types were given as two meal sizes with energy supply corresponding to 23% and 49% of predicted basal metabolic rate. Thus, meals with three different glycemic loads (95, 45–48 and 22 g) were administered. Blood samples were taken before and after each meal to determine glucose, free-fatty acids, insulin and glucagon concentrations over a 5-h period.

Results

An almost 2-fold higher serum glucose and insulin incremental area under the curve (AUC) over 2 h for the high- versus low-glycemic index same sized meals was observed (p < 0.05), however, for the serum glucose response in small meals this was not significant (p = 0.38). Calculated meal glycemic load was associated with 2 and 5 h serum glucose (r = 0.58, p < 0.01) and insulin (r = 0.54, p < 0.01) incremental and total AUC. In fact, when comparing the two meals with similar glycemic load but differing carbohydrate amount and type, very similar serum glucose and insulin responses were found. No differences were observed for serum free-fatty acids and glucagon profile in response to meal glycemic index.

Conclusion

This study showed that foods of contrasting glycemic index induced a proportionally comparable difference in serum insulin response when provided in both small and large meals. The same was true for the serum glucose response but only in large meals. Glycemic load was useful in predicting the acute impact on blood glucose and insulin responses within the context of mixed meals.     

Development of a healthy biscuit: an alternative approach to biscuit manufacture

Objective  

Obesity (BMI >30) and related health problems, including coronary heart disease (CHD), is without question a public health concern. The purpose of this study was to modify a traditional biscuit by the addition of vitamin B₆, vitamin B₁₂, Folic Acid, Vitamin C and Prebiotic fibre, while reducing salt and sugar.     

The development of a practical antioxidant for lard and shortening

Summary The process of developing a practical antioxidant consisting of natural occurring food substances has been described. The efficiency of the final product, which is based upon wheat-germ oil extracted from wheat-germ by means of ethylene dichloride and which contains added citric acid, has been verified by means of a modified Swift test, oxygen absorption and peroxide estimations. The practicability of the antioxidant has been demonstrated on a plant scale. Macdonald College Journal Series No. 185.     

Some practical aspects of thin-layer chromatography of lipids

This report describes methods for the thin-layer chromatography (TLC) of lipids and some practical aspects of the methods. In order to present some basis for choosing the correct powder for particular separations, some properties of several widely used silica gel powders are compared. The effect of binder material such as calcium sulfate in silica gel is studied. The three systems, silica gel as a polar phase, silver nitrate-impregnated silica gel, and reversed phase systems are described with application to neutral lipids. Also included are the applications of TLC to the polar lipids, such as phospholipids, cerebrosides, sulfatides, sphingomyelin and other glycolipids from various sources. The pitfalls and precautions involved in these separations are discussed in detail.     

Effects of high temperature storage upon lard as a raw material for shortening manufacture

Summary Storage of lard at 95°F. with the resultant development of peroxides had a detrimental effect on its flavor. Colors of the stored lards after deodorization were considerably darker than those of the fresh, and the flavor stabilities of the former were poorer. Partial hydrogenation did not stabilize the aged lards nearly as markedly as the fresh lards. The former had darker colors, lower A.O.M.’s, and poorer flavor stabilities. Presented at the 27th annual fall meeting, American Oil Chemists’ Society, Nov. 2–4, 1953, in Chicago, Ill.     

Some theoretical and practical aspects of polyester whitening from the wash bath

Uptake of fluorescent whitening agents from aqueous and organic systems by polyester fibers and films under various conditions was investigated. Different factors influencing the correlation between uptake of the fluorescent whitening agents and their performance in laundry liquors are discussed on the basis of the presented data. The results indicate that fluorescent whitening agents normally used for whitening other synthetic fibers can also have valuable additional effects on polyester. Furthermore the results are discussed in terms of the possible mechanisms of whitening.     

Some practical aspects connected with the presence of calcium in soybean oils

Presence of calcium in crude and degummed soybean oils prevents complete elimination of phosphatides by hydration and enhances the formation of heavy precipitates. They block industrial centrifuges at the later stages of the refining processes. Industrially extracted degummed soybean oils contain appreciable amounts of calcium (ca. 100 ppm) and its source was traced to the processed soybeans. Various pre-extraction treatments of the soybeans in industry augment the calcium content in the oils, since crude Soxhlet-extracted soybean oils contained only 15 ppm calcium. Additions at the alkali-refining stages of EDTA or of polyphosphate, to stabilize aqueous suspensions which also contain calcium salts, are suggested as a partial remedy to the frequent blocking of the centrifuges.     

Some practical aspects connected with the presence of calcium in soybean oils

Presence of calcium in crude and degummed soybean oils prevents complete elimination of phosphatides by hydration and enhances the formation of heavy precipitates. They block industrial centrifuges at the later stages of the refining processes. Industrially extracted degummed soybean oils contain appreciable amounts of calcium (ca. 100 ppm) and its source was traced to the processed soybeans. Various pre-extraction treatments of the soybeans in industry augment the calcium content in the oils, since crude Soxhlet-extracted soybean oils contained only 15 ppm calcium. Additions at the alkali-refining stages of EDTA or of polyphosphate, to stabilize aqueous suspensions which also contain calcium salts, are suggested as a partial remedy to the frequent blocking of the centrifuges.     

AutoCAD2006的几点实用技巧

AutoCAD丰富的绘图命令，强大的编辑功能，三维造型功能和良好的用户界面深受广大工程技术人员的普遍欢迎。在AutoCAD2005基础上，Autodesk公司又推出新一代设计产品AutoCAD2006。笔者在进行AutoCAD教学和软件开发时，获得一些体验，现总结出，以供大家使用AutoCAD2006时参考。     

Practical aspects of hydrogenation and soybean salad oil manufacture

Most edible oils are hydrogenated in batch-type slurry converters similar in basic design to those employed when the process was first commercialized in 1911. One major company uses a proprietary continuous slurry process. Other novel batch and continuous slurry systems are available but have not enjoyed significant commercial success. Fixed bed hydrogenation has not been seriously investigated but offers intriguing possibilities. Energy economy is assuming ever greater importance in the design of hardening systems. The accelerated growth of hydrogenation since the 1940s parallels the rapid increase in soybean oil use. In part, it reflects the flavor instability of soybean oil caused by its linolenic ester. When this triunsaturate is lowered by hydrogenation to ca. 3%, a high-quality soybean salad oil can be produced. Standard hydrogenation and separation techniques work well. New separation equipment and processes are entering the marketplace.     

Production aspects of the manufacture and operation of torcrete mixes

Production aspects of the manufacture and operation of torcrete mix MAGMS 85 are considered together with its main properties, i.e. transportability, efficiency during application to the surface of an intermediate ladle reinforcing layer, and also torcrete layer life. Results are provided for practical industrial tests of a torcrete mix with several versions of binder and the effect of them on the time for passage of a mix through an Engler viscometer is determined.     

Theoretical and practical aspects of preparing bipolar membranes

The mechanism of the function of bipolar membrane can be rationalized by a hypothesis which postulates a catalytic reaction for the electrodialytic water dissociation. Based on this hypothesis, chemical and thermal very stable bipolar membranes can be prepared as multilayer structures which can be operated efficiently at current densities in excess of 0.1 A/cm².     

The reaction occurring between gaseous CF4 and oxides dissolved in different molten fluorides. Some practical aspects

When CF₄ is bubbled through molten fluorides containing dissolved oxides within the range 900–1020° C, a chemical reaction takes place which decreases the oxide concentration and yields CO₂ and F^– ions. The possibility of the reaction between the CF₄ evolved at the anode and dissolved alumina, occurring during the anode effect in aluminium reduction cells, is discussed. This reaction provides a simple and convenient method for removing oxides and hydroxides from molten fluorides.     

Theoretical and practical aspects of selected fiber-blend color-formulation functions

Color matching blends of precolored fiber using three different methods was studied. Best color-matching accuracy was obtained using a two-constant Kubelka-Munk (KM) procedure. First-formula color differences averaged 1.6 CIELAB units and were found to be within the experimental error of 1.6 CIELAB units. Useful approximations were obtained using the methods proposed by Friele and by Stearns. First-formula color matches averaged 2.4 CIELAB units for the Stearns and 2.7 CIELAB units for the Friele methods. The methods are mathematically compared and the merits of each are discussed. Where possible, interpretation of the empirical parameters each method employs is attempted. It is pointed out that absorption and scattering constants calculated for fibers using the KM formalism are not true KM absorption and scattering constants. It is demonstrated that too literal an interpretation of these constants leads to apparent anomalies. It is shown that the fiber KM scattering constants which are normally considered unchanged as dye is applied cannot be considered unchanged if these same fibers are subsequently to be used in blends with other colored fibers.     

Some aspects on gas-solid flow in a U-bend: Numerical investigation

Pneumatic drying is widely used in many engineering applications. It has been shown in earlier research [Fyhr C. and Rasmuson A., Mathematical model of a pneumatic conveying dryer, AIChE Journal, Vol. 43, pp 2889-2902, 1997.] that the U-bends in the pneumatic conveying dryer system significantly influence drying behavior since they create enhanced slip velocities between suspended material and the drying medium. On one hand, this slip will increase external heat and mass transfer rates, thereby enhancing drying conditions. On the other hand, increasing the number of bends will cause an increase in pressure drop. Use of the suitable mean gas velocity and the suitable bend radius ratio will result in a better design and improved operating conditions.Two-phase CFD calculations, using a Eulerian-Eulerian model and commercial program Fluent 6.0, were employed to calculate the gas and particle flows in a U-bend. Variables studied include: particle diameter, particle density, particle volume fraction, gas velocity and bend radius ratio. The numerical calculations were validated against experimental data from the literature. The density and diameter of particle vary from 600 up to 1000 kg/m³ and from 0.00025 up to 0.001 m, respectively. The gas velocity and particle volume fraction vary from 10 up to 25 m/s and from 0.001 up to 0.01 m³/m³, respectively. The bend radius ratio varies from 3 up to 8 m/m. The slip velocity is affected by all the studied parameters, in particular, particle diameter, gas velocity and bend radius ratio; whereas the total pressure drop is strongly affected by gas velocity and bend radius ratio. A low mean gas velocity will give a lower total pressure drop and longer particle residence time. A small bend radius ratio will produce a faster dispersion of particles, which benefits drying, but on the other hand, will increase the total pressure drop. Thus, optimizing gas velocity and bend radius ratio is important in reducing energy consumption.     

New theoretical and practical aspects of the frying process

The deep‐frying process, normally carried out at 140–200 °C, is a very complex system due to the combination of heat and mass transfer between food and frying medium. The system becomes more complicated as the frying operation proceeds, because the composition of the food being fried and the frying medium is changing continuously due to the progressive deterioration of the frying medium. Apart from a variety of chemical reactions occurring, several changes take place in the frying food, such as gelatinisation of starch, denaturation of protein, and decrease of moisture. These changes bring about swelling of the product, formation of a crusty layer, and the appearance of a golden colour, good texture and taste. The precise control of the fryer enables these physical and chemical changes in the frying of food to convert it into a desirable finished product. This article discusses various types of reactions occurring in the food frying operation, possible mechanisms, a new realistic method – OSET index for measuring heat stability of frying oils – and the protective behaviour of substances that enhance the frying stability of oils.     

Ventilated tunnel solar dryers for small-scale farmers communities: Theoretical and practical aspects

The design of so-called “ventilated tunnel solar dryers" is presented in this work under theoretical and practical aspects. These dryers consist in a tunnel with a black floor and a plastic top, ventilated with fans supplied by a photovoltaic module. Along this tunnel, the air first passes through a heating part, which is product free and where the air is heated due to greenhouse effect. It then enters the second part of the dryer, the drying part, where the products to dry are spread. A rational and general design procedure based on the solving of energy and mass balance equations is developed and followed. This procedure allows designing the ventilation system and calculating the lengths of the heating and the drying parts of a dryer according to a scope statement and to design conditions insuring an efficient and homogeneous drying. Two dryers were designed, built and operated, in the frame of two development aid programs, in Cambodia and in Uganda. The fieldwork highlighted the importance of practical building and operating aspects, reported in the present paper, and of including people of the local communities in these programs. Results of field drying experiments are shown and demonstrate the validity of the design procedure. In particular, the validity of the energy balance equations at the basis of the procedure is demonstrated.