Evaluation of Sucrose Esters in Ice Cream

Sucrose esters of varying hydrophilic-lipophilic balance (HLB) values were added to standard ice cream mixes at 0.15 or 0.25%, and compared with ice creams containing either a commercially available or no emulsifier. Resulting viscosities and overrun patterns were similar, but surface tensions decreased with increasing HLB and concentration. The addition of sucrose esters at 0.25% tended to prevent clumping out of fat particles. Sucrose ester-containing samples melted in a normal manner, and only texture differences were detectable among samples, with the ester-containing samples rated higher than the control or reference samples initially and similar to the reference after storage.     

Determination of Ice Cream Mix Freezing Points: A Comparison of Methods

Ten batches of ice cream mix, varying in composition, were prepared. Mix freezing points were calculated by a formula method, determined by an osmometer, and the results of two methods were compared. Mix freezing points calculated by the formula method ranged from −2.36 to −3.59°C (−2.741°C mean); freezing points determined by the osmometer ranged from −2.40 to −3.53°C (−2.745°C mean). Comparative results of these methods differed by an average of .04 ± .02°C. The correlation coefficient between the two methods was .996, and there was no significant difference between them.     

The Effects of Fat Structures and Ice Cream Mix Viscosity on Physical and Sensory Properties of Ice Cream

The purpose of this work was to investigate iciness perception and other sensory textural attributes of ice cream due to ice and fat structures and mix viscosity. Two studies were carried out varying processing conditions and mix formulation. In the 1st study, ice creams were collected at ?3, ?5, and ?7.5 °C draw temperatures. These ice creams contained 0%, 0.1%, or 0.2% emulsifier, an 80:20 blend of mono‐ and diglycerides: polysorbate 80. In the 2nd study, ice creams were collected at ?3 °C draw temperature and contained 0%, 0.2%, or 0.4% stabilizer, a blend of guar gum, locust bean gum, and carrageenan. Multiple linear regressions were used to determine relationships between ice crystal size, destabilized fat, and sensory iciness. In the ice and fat structure study, an inverse correlation was found between fat destabilization and sensory iciness. Ice creams with no difference in ice crystal size were perceived to be less icy with increasing amounts of destabilized fat. Destabilized fat correlated inversely with drip‐through rate and sensory greasiness. In the ice cream mix viscosity study, an inverse correlation was found between mix viscosity and sensory iciness. Ice creams with no difference in ice crystal size were perceived to be less icy when formulated with higher mix viscosity. A positive correlation was found between mix viscosity and sensory greasiness. These results indicate that fat structures and mix viscosity have significant effects on ice cream microstructure and sensory texture including the reduction of iciness perception.     

Adaptation of lnstron to Determine the Surface Tension of Ice Cream Mix

A study was conducted to compare surface tension values measured by the DuNouy Method using the Cahn Electrobalance (an accepted procedure) with a procedure developed for use with an Instron. Surface tension was measured on a standard ice cream mix. Results indicate that the method developed for the Instron gave results which were not only similar to the Cahn Electrobalance procedure but also more precise.     

Rheology of Ice Cream Mix Flavored with Black Tea or Herbal Teas and Effect of Flavoring on the Sensory Properties of Ice Cream

Rheological characteristics and physicochemical properties of ice cream mix flavored with black tea or some herbal teas and sensory profile of flavored ice cream was investigated. In this respect, black tea and three different herbal tea samples (sage, chamomile, and linden) were used to produce a new ice cream formulation. Some physicochemical properties and sensory characteristics of samples were determined. Total phenolic content of ice cream samples increased with the use of tea or herbal teas and it was in the range of 123.37–415.20 mg kg^?1. Incorporation of black tea and herbal tea except chamomile decreased the sensory scores of ice cream compared to control sample. The apparent viscosities of samples were measured as a function of shear rate and consistency coefficient and flow behavior index were calculated by using power law model. All ice cream mix samples showed non-Newtonian pseudoplastic behavior. The apparent viscosities of ice cream mixes treated with no tea at the shear rate of 50 s^?1 were 1.13, 0.91, and 0.76 Pa s at 10, 20, and 30 °C, respectively. The activation energy for the viscosity change of the samples ranged between 10.87–20.25 J?mol^?1 at 50 s^?1.     

Temperature Dependency of Steady, Dynamic, and Creep-Recovery Rheological Properties of Ice Cream Mix

In this study, effect of processing temperature (5, 15, 25, and 35 °C) on the steady, dynamic, and creep recovery rheological properties of the ice cream mix (ICM) was investigated. It was found that processing temperature significantly affected all rheological parameters of the ICM sample. The flow behavior of the ICM sample was fitted to the Ostwald de Waele model. The magnitude of storage modulus (G′) was higher than that of loss modulus (G″) indicating that ICM sample had weak gel-like structure. Modified Cox–Merz rules were satisfactorily applied to the ICM sample to observe relationship between steady and dynamic shear properties. Additionally, Burger model was used to characterize the viscoelastic properties of the ICM sample. The gel strength (S) value was also calculated, and a decrease was observed with the increase of temperature. Arrhenius equation satisfactorily described the temperature dependency of the rheological parameters such as apparent viscosity at 50 s^?1 (η ₅₀), consistency coefficient (K), the instantaneous shear modulus of the Maxwell unit (G ₀), permanent deformation (J _∞ ), and S values that may be predicted by using established equations depending on the temperature. The increase in processing temperature caused a decrease in resistance of the mixture subjected to the deformation, which is very important for production of high quality ice cream.     

冰淇淋生产中老化条件的确定

冰淇淋生产中老化条件的确定是冰淇淋质量好坏的重要因素之一。根据冰淇淋的实际生产配方、加工工艺与条件，测定料液在老化时粘度的增长情况。通过凝冻操作鉴定冰淇淋质量，最终确定料液所需老化时间。     

应用高效液相色谱快速测定奶粉中的乳糖,蔗糖,葡萄糖

讨论了应用高效液相色谱（ＨＰＬＣ）对奶粉及调制奶粉中的乳糖,蔗糖,葡萄糖的一种快速测定方法。样品经简单的前处理后由Ｃａｒｂｏｈｙｄｒａｔｅ Ａｎａｌｙｓｉｓ柱分离,流动相为乙腈／水,示差折光检测,奶粉中乳糖,蔗糖,葡萄糖完全分离并定量测定。方法简便,快速,结果令人满意。     

结晶原理和冰淇淋中的结晶现象

阐述了结晶原理在冰淇淋凝冻中的应用,详细叙述了结晶的目的和方法,晶核的形成原理,结晶体的成长,多晶现象,以及冰淇淋中的结晶现象.     

离子色谱法测定奶粉中的葡萄糖、蔗糖和乳糖

建立高效阴离子交换色谱-脉冲安培检测法测定奶粉中葡萄糖、蔗糖和乳糖的方法。以METROSEP CARB 1(150mm×4.0mm)阴离子交换柱为分离柱,脉冲安培检测,37mmol/L NaOH溶液为淋洗液,以柠檬酸作为蛋白质沉淀剂。葡萄糖、蔗糖和乳糖的线性范围分别为1～40、1～50、1～50mg/L,相关系数分别0.9966、0.9968、0.9985,检出限分别为0.014、0.091、0.083mg/L,精密度为1.10%～4.96%,回收率为90.13%～104.83%。该方法分析时间短,前处理简单,适用于快速测定奶粉中的葡萄糖、蔗糖和乳糖。     

美国冰淇淋质构的发展动向与中国的对策

冰淇淋质构影响冰淇淋的口感、抗化度、抗变形度、质地松软度或坚实度、冰的晶态、冰晶的分布位置和定向.控制水分活度,选择冰淇淋乳化剂、冰淇淋增稠剂、冰淇淋辅料,配合恰到好处的工艺条件,可控制冰淇淋质构.     

Determination of Enterotoxigenic and Methicillin Resistant Staphylococcus aureus in Ice Cream

The aim of this study was to determine the prevalence of enterotoxigenic and methicillin‐resistant Staphylococcus aureus in ice creams. After culture‐based identification of isolates, the presence of 16S rRNA and nuc was confirmed by mPCR. S. aureus was identified in 18 of 56 fruity (32.1%), 4 of 32 vanilla (12.5%), and 1 of 12 chocolate (8.3%) ice creams. S. aureus was identified as 38 isolates in 23 ice cream samples by culture‐based techniques, but only 35 isolates were confirmed by PCR as S. aureus. To determine the enterotoxigenic properties of PCR‐confirmed S. aureus isolates, a toxin detection kit was used (SET RPLA®). Of the 12 enterotoxigenic S. aureus isolates, 9 SEB (75%), 1 SED (8.3%), 1 SEB+SED (8.3%), and 1 SEA+SEB+SED (8.3%) expressing isolates were found. The presence of enterotoxin genes (sea, seb, sed) was identified in 13 (37.1%) out of 35 isolates by the mPCR technique. In the ice cream isolates, the sea, seb, and sed genes were detected: 1 sea (7.6%), 9 seb (69.2%), 1 sed (7.6%), 1 seb+sed (7.6%), and 1 sea+seb+sed (7.6%), respectively. The sec gene was not detected in any of these isolates. One of the 35 (2.8%) S. aureus strain was mecA positive.     

高效液相色谱法快速测定冰淇淋中的糖精钠

本文采用高效液相色谱法快速测定冰淇淋中的糖精钠。色谱柱为径向压缩柱，紫外检测定量。样品用硫酸铜及氢氧化钠溶液处理后，滤液不用萃取即可上机测定。     

冰淇淋中冰晶的形成

用图形分析了-2.5～-30℃下,凝冻水的含量对冰晶形成的影响,同时分析了凝冻、储藏和分布等因素对冰晶形成的影响。