月桂酸类代可可脂巧克力脂霜组成及形态学研究

通过气相色谱分析和显微镜观察对起霜前后月桂酸类代可可脂巧克力的脂肪酸组成以及形态学特征进行了研究。结果表明,与新鲜巧克力相比,脂霜中C12∶0、C18∶0、C18∶1含量明显增加,而C14∶0含量相对减少;原子力显微镜结果显示,新鲜巧克力表面相对平滑,起霜后平滑表面破坏,形成明显凹凸面;扫描电镜观察发现新鲜巧克力表面结晶网络结构疏松,起霜巧克力表面油脂晶体形成致密网络结构;偏光显微镜显示脂霜中晶体颗粒明显大于新鲜巧克力晶体颗粒,发生了向更稳定晶体的转变。     

以酯交换及分提技术制取代可可脂的研究

以极度氢化油（主要脂肪酸为软脂酸和硬脂酸）和茶油为原料，按适当比例混合后随机交酯化，采用丙酮溶剂分提法制取代可可酯。经研究证实交酯反应的最佳工艺参数是：反应温度８０℃，催化剂浓度０．４％（ｗｔ），反应时间３０ｍｉｎ．选用两步溶剂分提工艺制取成品，结晶温度分别为１９℃（或１７℃）和２℃．产品的ＳＦＩ曲线以及甘三酯组成分析结果表明：代可可脂的熔化性能与天然可可脂相似，但蜡感较重，与天然可可脂相混时，添加量小于３０％，相容性较好。     

The advantages of solid fat content determination in cocoa butter and cocoa butter equivalents by the Karlshamns method

This paper describes the preparation of samples and the evaluation techniques applied to determine the Solid Fat Content (SFC) by means of pulsed nuclear magnetic resonance (NMR) in confectionery fats characterized by distinct polymorphism (cocoa butter, cocoa butter equivalents and their mixtures). Due to the deviation of SFC values in certain softer cocoa butter equivalents at the temperature of 20 °C, an internal method devised at Karlshamns Oils & Fats AB is applied as well. When compared to the official IUPAC 2.150 (b) method, Karlshamns' method involves a lower temperature and a prolonged period of time at the stage of the final SFC stabilization in the pre-treatment of fat samples. The calculation of SFC in the analysed samples for the purposes of this paper was carried out by employing both methods (the indirect method and a serial procedure). The results are presented graphically. Differences were reflected in the SFC of the fats and their mixtures that were under observation depending on the method and temperatures applied. The obtained results indicated a considerable advantage of employing the Karlshamns method since the results yielded by this method are more lucid. Moreover, the behaviour of fats in the production process can be more easily predicted on the basis of these results.     

Effect of the Addition of a Cocoa Butter–Like Fat Enzymatically Produced from Olive Pomace Oil on the Oxidative Stability of Cocoa Butter

ABSTRACT:  A cocoa butter (CB)–like fat was produced in a packed bed enzyme reactor using sn -1,3 specific lipase, and its blends with CB were prepared at different ratios (CB: CB-like fat; 100: 0, 90: 10, 80: 20, 70: 30, 60: 40, 50: 50, 0: 100). The oxidation kinetics of CB: CB-like fat blends was studied by differential scanning calorimeter (DSC). Samples were heated in DSC at different temperatures (130, 140, 150, 160 °C) under 100 mL/min oxygen. From DSC exotherms, oxidation induction times (OIT) were determined and used for the assessment of the oxidative stabilities of the blends. Oxidation kinetics parameters (activation energy, E_a ; preexponential factor, Z ; and oxidation rate constant, k ) were calculated. In general, it has been observed that above 110 °C increasing the ratio of CB-like fat in the blend increased the k value with increasing temperature. It has been observed that for all blends the increase in k value with temperature was significant ( P < 0.05). Increasing CB-like fat ratio in the blend decreased the content of major TAGs (1,3-dipalmitoyl-2-oleoyl-glycerol [POP]; 1[3]-palmitoyl-3[1]stearoyl-2-oleoyl-glycerol [POS]; 1,3-distearoyl-2-oleoyl-glycerol [SOS]), and decreased the oxidative stability of the blends.     

超临界CO_2萃取可可脂与可可色素的实验研究

本课题设计和建立了一套超临界萃取扩大试验装置，实现了用超临界ＣＯ_２同时萃取可可豆壳（或皮）中可可脂及可可色素的工艺。通过静态与动态试验获得了最佳工艺条件。试验结果表明超临界萃取法还具有工艺简单、操作安全、产品质量好、能耗低和萃取率高等优点。     

Cocoa butter fats and possibilities of substitution in food products concerning cocoa varieties,alternative sources,extraction methods,composition, and characteristics

The current concern for cocoa butter fat as major ingredients of chocolate intake in the World has raised the question of the high price of cocoa butter among all other vegetable fats. Productions of natural cocoa butter fats are decreasing day by day due to the decrease of cocoa cultivation worldwide; moreover, cocoa fruit contains only a little amount of cocoa butter. Therefore, the food industries are keen to find the alternatives to cocoa butter fat and this issue has been contemplated among food manufacturers. This review offers an update of scientific research conducted in relation to the alternative fats of cocoa butter from natural sources. The findings highlights how these cocoa butter alternatives are being produced either by blending, modifying the natural oils or fats from palm oil, palm kernel oil, mango seed kernel fats, kokum butter fat, sal fat, shea butter, and illipé fat.     

Physical and Sensory Properties of Milk Chocolate Formulated with Anhydrous Milk Fat Fractions

Maximum additions of milk fat that produced temperable milk chocolates were anhydrous milk fat (AMF), middle-melting fraction (MMF) or low-melting fraction (LMF) up to 40 wt % total fat, and high-melting fraction (HMF) up to 35%. The solid fat content (SFC), melting point, melting enthalpy, instrumental and sensory hardness of milk chocolates decreased with increasing milk fat addition. No differences in sensory attributes sweetness, milk powder, chocolate, butter flavor or thickness of melt were observed. Chocolate with 40% MMF or LMF had greater milk flavor than that with 12.2% HMF. Onset of melt correlated (r = 0.96) with melting enthalpy. No differences between types of milk fat (AMF, HMF, MMF, LMF) were observed for any textural attribute assessed.     

Combination of the Simple Additive (SAW) Approach and Mixture Design to Determine Optimum Cocoa Combination of the Hot Chocolate Beverage

Physicochemical (pH, brix, and color), sensory (color, taste, odor, mouthfeeling, consistency, bitter flavor, and general acceptability), and rheological properties of the hot chocolate beverages including different cocoa combinations were investigated in the present study. Cocoa type significantly affected all of the properties. Simple additive weighting approach was applied to obtain one score from seven different sensory parameters and simple additive weighting score was used in mixture design to determine optimum cocoa type or cocoa combination. Ostwald de Waele model described the flow behavior of the hot chocolate beverage samples with R² values ranged between 0.818 and 0.999. The consistency coefficient (K) and apparent viscosity at shear rate 50 s^?1 (η₅₀) were significantly affected by cocoa type found in the formulation of the beverage. The mixture design approach was performed in order to determine variation of the responses (physicochemical, sensory, and rheological parameters) as a function of cocoa concentration. Simple additive weighting scores were satisfactorily described by established equation as a function of cocoa concentration to be used in the formulation of the hot chocolate beverage (R² = 0.8645).     

不同结晶态脂肪比例对乳液奶油感感知的影响

通过调配无水乳脂肪的脂肪酸组成,构建含不同结晶态比例的乳脂肪模型和与牛奶脂肪含量和粒径匹配的乳液体系,进而模拟口腔加工,测定含不同结晶态脂肪比例乳液的口腔聚合性和摩擦学特性,并评价其奶油感。成功构建了含不同结晶态比例（10%～85%）的乳脂肪模型（F10～F85）,所构建乳液（E10～E85）中脂肪球平均粒径为4 μm,在模拟口腔加工后,乳液粒径显著增大,其中E40样品增大程度最大。随着结晶态脂肪比例的增加,乳液口腔摩擦系数（μ20）先减小后增加,其中E40样品μ20最小,为（0.04±0.01）。描述性感官评价结果显示,随着结晶态脂肪比例的增加,乳液样品的整体奶油感先增大后减小,其中E40样品得分最高,为8.06±0.73。主成分分析结果显示,乳液的口腔光滑感和糊口感与整体奶油感相关性最强,其中E40样品与整体奶油感相关性最强。暂时性感官支配评价结果显示,口腔加工中后期,乳液在口腔感知中最显著的优势感官属性为口腔光滑感和糊口感,其中E40样品的口腔光滑感和糊口感优势率最高。本研究明确了结晶态脂肪比例对乳液奶油感感知的影响,为开发低脂但具备全脂口感的乳制品提供理论依据。     

广西水牛奶脂肪含量对感官特性的影响

以荷斯坦牛奶为对照品,分析了广西水牛奶的主要成分、理化指标和粒径分布特点,发现两种牛奶的非脂乳固体、酸度、pH值等指标并无明显差异．水牛奶的蛋白质、脂肪、总固形物质量分数及电导率明显高于荷斯坦牛奶,特别是脂肪质量分数差异尤为明显。两种牛奶脂肪在粒经分布上也表现出不同的特点,水牛奶的脂肪粒径在0．5～20μm之间,而荷斯坦牛奶的粒径在0．5～10μm之间。为此,进一步比较分析了不同脂肪质量分数水牛奶的感官差异．发现水牛奶的风味受脂肪质量分数很大的影响．提示在开发水牛奶产品时应注意调节脂肪质量分数。     

牦牛肝脏中脂肪含量与食用品质、脂肪酸组成的相关性

研究牦牛肝脏中脂肪含量与食用品质及脂肪酸组成之间的关系。以海北牦牛为研究对象、当地同龄黄牛为对照,采用内标法对肝脏的脂肪酸组成进行测定并对脂肪含量与食用品质、脂肪酸组成进行相关性分析。结果显示：牦牛肝脏色度a*值极显著高于对照组（P＜0.01）,失水率极显著低于对照组（P＜0.01）;饱和脂肪酸含量极显著低于对照组（P＜0.01）;两者的功能性脂肪酸有极显著差异（P＜0.01）;牦牛肝脏P/S值为0.51,符合世界卫生组织推荐的大于0.4的标准,n-6/n-3值小于营养学上建议的标准。相关性分析表明：肝脏脂肪含量与失水率呈极显著正相关（P＜0.01）;肝脏脂肪含量与饱和脂肪酸、单不饱和脂肪酸、硬脂酸、二十碳五烯酸、二十二碳六烯酸含量呈显著正相关（P＜0.05）,与多不饱和脂肪酸含量呈极显著负相关（P＜0.01）。因此,牦牛肝脏具有优良的食用品质和较高的营养价值。     

Characteristics of palm mid-fractions produced from different fractionation paths and their potential usages

Three palm mid-fraction (PMF) groups produced from different fractionation paths were analyzed in terms of the fat, triacylglycerol and sn-2 fatty acid compositions, thermal properties (melting and crystallization behaviors, and solid fat contents (SFCs)), micronutrient levels and oxidative stability indexes (OSIs) to achieve their sufficient utilization. PMF-A (iodine value (IV), 48.4 g/100 g) fractionated from palm olein contained 43.8% 1,3-dipalmitoyl-2-oleoyl-glycerol (POP) and 16.7% 1-palmitoyl-2,3-dioleoyl-glycerol, showing soften properties (slip melting point (SMP), 27.6°C; SFC at 30°C, 2.2%) at hot weather. PMF-B (IV, 42.3 g/100g) obtained from palm stearin showed similar fat and triacylglycerol compositions as PMF-A, but the high 1,2,3-tripalmitoyl-glycerol level (6.2%) improves its thermal behaviors (SMP, 34.9°C; SFC at 30°C, 13.8%). The SFC profiles of PMF-A and PMF-B were comparable to those found in frozen and puff margarine shortenings. Furthermore, both of the PMF groups exhibited excellent OSIs (13.2 and 11.2 h, respectively) because of their high micronutrient levels (especially γ-tocopherol and campesterol). In general, γ-tocopherol and campesterol contribute to preventing lipids from oxidation under frying conditions. Therefore, PMF-A and PMF-B are recommended for manufacturing margarine shortenings and frying fasts. PMF-C (IV, 33.0 g/100g) produced from the additional fractionation of PMF-A or PMF-B contained the highest POP percentage (67.1%) and showed heat-resistant property (SMP, 31.8°C; SFC at 30°C, 22.4%). Its steep SFC profile was superior to that of cocoa butter, suggesting the fat is preferred in producing hard chocolate fats.     

Physical properties of tempered mixtures of cocoa butter,CBR and CBS fats

Physical characteristics of precrystallised binary mixtures of cocoa butter (CB) and 5, 10, 15, 20, 25 and 30% (w/w) cocoa butter replacer (CBR) or cocoa butter substitute (CBS) were determined. The lipid composition was obtained by chromatography and the solid fat content (SFC) by nuclear magnetic resonance. Tempering was carried out using a lab‐scale agitated jacket vessel reactor. Bars made with tempered samples were submitted to X‐ray diffraction and rupture tests. Snap values of crystallised mixtures decrease with an increase in the amount of alternative fat. X‐ray diffraction patterns confirmed the predominant formation of the beta polymorph habit for CB and beta prime form for CBR and CBS. Mixtures of CB and CBR exhibit chemical compatibility. The knowledge of the snap values and of the variation of SFC with temperature proved to suffice to adequately anticipate the influence of the addition of alternative fats on chocolates physical attributes.     

不同烹调方法对鱼营养价值及感官评价的影响

通过分析鲟鱼和罗非鱼经清蒸、微波、微波烤、烤箱烤、油煎、高压6种不同烹调处理后水分、脂肪含量的变化,探讨烹调后水分、脂肪含量与质构特性和感官特性的相关性,找到适合水产品烹调方式,使水产品的营养价值得到最大的保存率,以此指导人们合理膳食。结果表明：清蒸烹调后水分含量最大,整体可接受性最高。相关性分析表明：烹调后样品的水分含量与多汁性及弹性有显著正相关性,而脂肪含量与硬度有极显著负相关性,与内聚性具有负相关趋势。以质构指标预测感官特性的预测方程构成因鱼种而有所差异。     

花生酱制备工艺、品质分析及安全性评价研究进展

花生酱含有丰富的蛋白质、维生素和矿物质等,营养丰富,风味独特。本文在文献统计基础上,重点阐述了花生酱制备工艺、品质分析及安全性评价的研究进展。其制备工艺的流程为烘烤、冷却、去皮、一次碾磨、搅拌、二次碾磨和装罐;品质分析包括食用品质（色泽、质构与风味物质）、理化品质（粗蛋白、粗脂肪等）、稳定性分析（货架期和油分离）;安全性评价包括黄曲霉毒素、沙门氏菌等。最后对花生酱制备工艺、品质分析及安全性评价研究中存在的问题和重点方向进行了总结和展望。     

花生、脂肪和淀粉添加量对香肠感官评价和质构的影响

为了确定香肠中花生、脂肪和淀粉的添加量对香肠质量的影响和最优配比,采用三因素三水平L,（3^4）正交试验设计对花生、脂肪和淀粉添加量进行优化,花生添加量的三个水平分别为3％、5％、8％,脂肪添加量的三个水平分别为12％、15％、18％,淀粉添加量的三个水平分别为6％、9％、12％。应用感官评分法对香肠外观、组织状态、气味、色泽、口感、切片性和耐煮性进行评分,并采用质构剖面分析方法对香肠硬度、弹性、黏聚性和咀嚼性进行测定。结果表明：感官评定与质构测定结果较一致,最佳组合均为5％花生、12％脂肪和9％淀粉。极差分析发现,花生含量对香肠的硬度、弹性和黏聚性影响最大（极差分别为2497．72、0．26和0．16）,而脂肪对香肠的咀嚼性影响最强,淀粉添加量对质香肠构影响较弱。     

非脂乳固体和脂肪含量对酸牛乳粘度的影响

通过调整酸牛乳配方中非脂乳固体和脂肪的含量,使酸牛乳粘稠度发生变化,找出它们之间的关系。确定最佳粘稠度的配方。     

Effect of Moisture Content of Carrot Slices on the Fat Content, Carotenoid Content, and Sensory Characteristics of Deep-fried Carrot Chips

ABSTRACT: Our objective was to develop a reduced-fat deep-fried carrot chip. Moisture contents of the carrot slices were altered, and fat uptake and quality parameters were measured. Decreasing moisture content of carrot slices significantly decreased ( P < 0.05) the yield, hue∘ value, and fat uptake, and increased the redness value, which correlated with increased carotenoid content, but did not influence chip lightness, yellowness, water activity, and moisture content. Removing 50% of the initial moisture content of the carrot slices decreased the chips' fat content from 57% to 38.5%. Adjusting the moisture level of the carrot slices appears to influence fat uptake and carotene content of deep-fried carrot chips.     

Fat Content Effects on Yield, Quality, and Microbiological Characteristics of Chicken Patties

Mixtures of ground chicken thigh meat and fat were formulated to contain 5, 10, 15, and 20% fat. Hunter color values, drip and cooking losses, proximate composition, texture profiles, and rates of microbial spoilage were compared for patties prepared from the mixtures. Raw patties became lighter and more yellow as fat content increased but cooking obscured these trends. As fat content increased, cooking losses and moisture:protein ratios increased. Lower fat patties were harder, springier, less cohesive and chewier than patties containing higher fat levels. Rates of bacterial spoilage were unaffected by fat content.