单硬脂酸丙二醇酯及其应用

高纯度单硬脂酸丙二醇酯多作为乳化剂在食品工业中广泛应用，阐述了单硬脂酸丙二醇酯的性质、生产、质量及其在食品中的应用状况。     

Recrystallization in Ice Cream as Affected by Stabilizers

Addition of locust bean gum (LBG) or guar gum to ice cream mixes gave products with smaller ice crystals after heatshock than control samples without either stabilizer. LBG was more effective at inhibiting recrystallization than guar. Increasing stabilizer concentration resulted in greater inhibition. With LBG we found some evidence for an optimum concentration above which no further inhibition occurred. We found no evidence for phase volume effects.     

Effect of biopolymers on structure and ice recrystallization in dynamically frozen ice cream model systems

Ice crystal growth and microstructure of sugarsolutions prepared with stabilizers (carboxymethyl cellulose [CMC], xanthan gum, locust bean gum [LBG], and gelatin) with or without milk solids-nonfat (MSNF) after freezing in a scraped surface heat exchanger and temperature cycling (5 cycles from -6 degrees C to -20 degrees C) were studied. Ice crystal growth was calculated from brightfield microscopic images acquired from samples before and after cycling. Freeze-substitution and low-temperature embedding (LR-Gold resin) were sample preparation techniques utilized for structure analyses by light microscopy and transmission electron microscopy. Differential staining for carbohydrates and proteins allowed the identification of stabilizer gel-like structures in LBG, gelatin, and gelatin/MSNF solutions. In the absence of milk proteins, xanthan and LBG were the most effective at retarding recrystallization, while in their presence, only xanthan had an effect. Cryo-gelation of the LBG was observed but is not the only mechanism of stabilizer action. Thermodynamic incompatibility between biopolymers was observed to promote localized high concentrations of milk proteins located at the ice crystal interface, probably exerting a water-holding action that significantly enhanced the stabilizer effect. Qualitatively, solution heterogeneity (phase separation) was directly proportional to ice crystal growth inhibition. It is suggested that water-holding by stabilizer and proteins, and in some cases steric hindrance induced by a stabilizer gel-like network, caused a reduction in the kinetics of the ice recrystallization phenomena and promoted mechanisms of melt-regrow instead of melt-diffuse-grow recrystallization, thus resulting in the preservation of the ice crystal size and in a small span of the ice crystal size distribution.     

分销环节冰淇淋感观质量下降的原因及其对策

简要介绍了冰淇淋在分销环节感观质量下降的原因和控制方法 ,同时强调了对冰淇淋产品分销链操作人员培训的重要性。     

Modeling Ice Crystal Coarsening in Concentrated Disperse Food Systems

Recrystallization of ice in frozen concentrated aqueous sugar solutions was treated as a diffusion controlled process and has been modeled using a combination of a modified Lifshitz, Slyozov and Wagner theory for coarsening in dispersed phase systems and a mean field theory. The model has been tested using aqueous fructose solutions, water ices and ice creams under a range of time and temperature histories. The model provides data which are in accord with experiments and also suggests that recrystallization cannot be modeled using only diffusion. In certain circumstances other processes must also be considered.     

Recrystallization in Model Ice Cream Solutions as Affected by Stabilizer Concentration

Ice recrystallization rates in simple aqueous solutions comprising fructose and a hydrocolloid stabilizer were measured. The stabilizers were an enzyme-modified guar and a non-gelling high methoxy pectin. The stabilizer concentration dependence of the recrystallization rates for both materials was similar in that increasing the concentration resulted in decreasing rates until a point is reached where further addition had no additional effect. That recrystallization rates were reduced by both gelling and non-gelling stabilizers was strongly suggestive that gelation was not a requirement for recrystallization inhibition and another more specific mechanism applies, for example a weak interfacial effect such as adsorption or blocking. This behavior was also seen with locust bean gum and guar and provided further empirical evidence to support the hypothesis that stabilizers adsorb to ice crystal surfaces.     

植物基食品研究进展

冰淇淋作为广大消费者喜爱的冷冻甜点,不仅具有独特的口感,而且还极具营养价值。随着人们对健康饮食的重视,蛋白质冰淇淋受到消费者的广泛关注。因此,了解蛋白质对冰淇淋结构以及冰淇淋品质的影响,对促进蛋白质冰淇淋的发展具有重要意义。本文深入阐述了冰淇淋结构的形成以及蛋白质对冰淇淋品质的影响,包括冰晶重结晶、脂肪部分聚结、膨胀率、融化率和贮藏稳定性等。同时还总结了动物蛋白和植物蛋白在冰淇淋中的研究进展,乳蛋白（乳清蛋白和酪蛋白）和大豆分离蛋白目前在冰淇淋中应用最广泛,对提高冰淇淋口感、抑制冰晶重结晶有显著作用。乳清蛋白冰淇淋存在抗融效果差的问题,此可以通过与植物蛋白复配来提高冰淇淋品质。此外,蛋白质作为冰淇淋中脂肪替代物和天然乳化剂成为新的研究热点,本文总结了其研究现状,并对未来蛋白质在冰淇淋中的应用进行了展望。

     

油脂对植物基冰淇淋乳液性质及产品品质的影响

为探究植物油在植物基冰淇淋中的应用情况,以4种不同脂肪酸特征的植物油替代无水奶油制作改性大豆分离蛋白冰淇淋,并以无水奶油乳蛋白冰淇淋作为对照,研究不同油脂的结晶特性及由其制作的冰淇淋的品质,并进一步考察其对冰淇淋乳液性质的影响。结果表明：富含中链脂肪酸的棕榈仁油、氢化椰子油和氢化棕榈仁油形成了针状的β′晶型,含有60.21%棕榈酸的棕榈油形成了圆形的β晶型;棕榈仁油含有16.37%油酸,晶体分布稀疏,氢化棕榈仁油硬脂酸含量较高,晶体较大;氢化椰子油合适的固体脂肪含量和较高的中链脂肪酸含量使其形成了密集的针状晶体,更易穿破界面膜并增加脂肪球的碰撞频率,促进了冰淇淋中脂肪的部分聚结;冰淇淋乳液均为非牛顿流体,在使用改性大豆分离蛋白后及凝冻搅打后,脂肪发生了絮凝和部分聚结,其黏度大幅提升;植物基冰淇淋乳液的储能模量大小与脂肪部分聚结度结果一致,且大于损耗模量;氢化椰子油改性大豆分离蛋白冰淇淋乳液的界面蛋白含量最低,为10.48 mg/m2,脂肪部分聚结度最高,为68.89%,且冰淇淋的膨胀率为66.15%,融化率为7.12%,滞后时间为212 s。综上,油脂的脂肪酸组成影响其结晶特性,进而影响冰淇淋的基本性质,氢化椰子油改性大豆分离蛋白冰淇淋的品质最好。     

实验制作高淀粉冰淇淋

介绍了高淀粉冰淇淋的配方和工艺要点,并对实际制作过程中的操作要点进行了论述,为冰淇淋生产厂降低生产成本,寻找新的原料和食品添加剂提供了一种方法。     

丙二醇酯中游离丙二醇含量的直接测定

提出丙二醇酯中游离丙二醇含量的直接测定方法。该法和萃取法对一系列样品进行对照试验,经数理统计分析,结果表明,两种测定方法没有显著性差异。直接法更简单、快捷。回收率为95.7?.0%,相对标准偏差为0.23%0.60%。     

益生菌冰淇淋的开发

近年来我国食品工业中,冰淇淋成为继饮料、方便面后发展最为迅猛的产品之一。如何将冰淇淋的嗜好性与产品的营养和功能特性进行有机结合,是冰淇淋产品未来重要的发展趋势。本文从冰淇淋发展简史与近年市场状况,益生茵的种类和作用,益生菌冰淇淋的优势、研究与开发方向等方面进行了概述。      

冰淇淋成分抑制冰晶重结晶机制及研究技术

冰淇淋的品质受到冷冻过程中产生冰晶的大小和数量的影响,冰晶重结晶形成的大冰晶使冰淇淋质地粗糙,冰晶感强,失去了冰淇淋应有的光滑细腻感。为了提高冰淇淋的品质和储存稳定性,本文深入阐述了冰晶重结晶的机制,首先总结了冰晶的3个过程,介绍了用于冰淇淋低温保护的成分,包括酶类物质、冰结构蛋白、膳食纤维等多糖类稳定剂等,提出多糖类稳定剂是目前抑制冰晶重结晶较为有效的方法,且成本低廉。同时总结了国内外研究冰淇淋重结晶的常用技术,分析了抑制冰晶重结晶的措施及机制,包括低温光学显微技术、聚焦光束反射技术和低场核磁共振技术,其中,低温光学显微技术是最有效的技术手段,该技术和其他技术的结合为优化冰淇淋品质提供了理论依据,以期为冰淇淋研发人员和生产厂家制作良好冻融稳定性冰淇淋提供科学依据和技术参考。     

棕榈油中间分提物(PMF)在冰淇淋中应用研究

通过对棕榈油中间分提物(PMF)理化性质分析,表明棕榈油中间分提物理化性质能满足生产冰淇淋要求,并用此特定油脂进行冰淇淋配方研究,确定PMF油基冰淇淋最佳配方:PMF添加量为6%、脱脂乳粉添加量为8%、糖添加量为13%、乳化剂添加量为0.5%、稳定剂添加量为0.2%。     

大豆冰淇淋的研制

研究了在传统冰淇淋的基础上加入大豆汁混合而成的大豆冰淇淋的技术工艺,该产品营养丰 富,味道可口,具有保健功能,是老少皆宜的冷饮食品。     

The use of spinning disc reactor for processing ice cream base – effect of ageing in making model ice cream

Spinning disc reactor (SDR) technology was tested to produce an ice cream base, which was subsequently used to make model ice cream. The ice cream base containing butterfat, lecithin, xanthan gum, sugar, skimmed milk and double cream was passed over the SDR disc spinning at 2900 rpm, heated at 80 °C and at a flow rate 6 mL s⁻¹. The physical properties of the SDR-processed ice cream base such as particle size and viscosity measurments, and of model ice cream including overrun, meltdown rate and sensory perception were investigated. The SDR-processed ice cream base exhibits narrow particle-size distribution (average particle d ₃₂ = 1.65 μm, d ₄₃ = 2.98 μm) and the viscosity was found to be similar at zero and 18 h ageing, whilst the model ice cream requires zero-hour ageing and has a high overrun value (∼85%) and slow meltdown rate as compared with a commercial sample. The results reveal that the SDR is capable of producing a highly stable ice cream base that requires significantly less ageing than the 18 h typically associated with the traditional process of making ice cream. The SDR process provides intense mixing of ingredients which facilitates the hydration of milk proteins and stabilisers.     

发酵黑小麦冰淇淋的研制

本文以黑小麦为原料,对发酵黑小麦冰淇淋加工中的麦汁糖化、乳酸菌驯化、发酵、稳定剂配方和生产工艺进行了探讨,经实验确定黑小麦酸奶在发酵温度为37℃时,发酵所需时间为6h,发酵黑小麦冰淇淋稳定剂的组成为0.4％耐酸CMC、0.8％的黄原胶、0.8％的瓜尔豆胶,该产品乳酸菌数为5.2×10℃FU/mL,具有良好的膨化率和抗融性。     

酸奶冰淇淋配方研究

对酸奶冰淇淋的配方组成进行了研究, 确定了酸奶冰淇淋配方的最佳组成。     

高麦芽糖浆在冰淇淋中的应用

本文研究了高麦芽糖浆作为甜味剂在冰淇淋中的应用。结果表明:高麦芽糖浆能改善产品组织,提高产品膨胀率。     

Properties of frozen dairy desserts processed by microfluidization of their mixes

Sensory properties and rate of meltdown of nonfat (0% fat) and low-fat (2% fat) vanilla ice creams processed either by conventional valve homogenization or microfluidization of their mixes were compared with each other and to ice cream (10% fat) processed by conventional valve homogenization. Mixes for frozen dairy desserts containing 0, 2, and 10% fat were manufactured. Some of the nonfat and low-fat ice cream mixes were processed by microfluidization at 50, 100, 150, and 200 MPa, and the remaining nonfat and low-fat ice cream mixes and all of the ice cream mix were processed by conventional valve homogenization at 13.8 MPa, first stage, and 3.4 MPa, second stage. The finished frozen and hardened products were evaluated at d 1 and 45 for meltdown rate and for flavor and body and texture by preference testing. Nonfat and low-fat ice creams that usually had a slower meltdown were produced when processing their mixes by microfluidization instead of by conventional valve homogenization. Sensory scores for the ice cream were significantly higher than sensory scores for the nonfat and low-fat ice creams, but the sensory scores for the conventional valve homogenized controls for the nonfat ice cream and low-fat ice cream were not significantly different from the sensory scores for the nonfat ice cream and low-fat ice cream processed by microfluidization of the mixes, respectively. Microfluidization produced nonfat and low-fat ice creams that usually had a slower meltdown without affecting sensory properties.