Effect of Food Matrix on Saltiness Perception—Implications for Sodium Reduction

Enhancing sodium release from the food matrix, thus increasing saltiness perception, is a promising strategy to reduce the amount of salt needed in foods. However, the complex nature of the effect of the food matrix on saltiness perception makes it difficult to control saltiness perception when designing food products. The aim of this review is to provide an overview of the food matrix effects on saltiness perception of sodium chloride. The effects are discussed in the order of 3 stages in saltiness perception: release of sodium from food matrix into oral cavity (1st stage), delivery of sodium within oral cavity (2nd stage), and detection of sodium by the taste receptor cells (TRCs) (3rd stage). In the 1st stage, the food matrix affects the initial availability of sodium to be released, and also affects the spontaneous and facilitated migration of sodium from the matrix into the oral cavity. In the 2nd stage, the food matrix affects the availability of sodium and the mixing efficiency of sodium with saliva. The relationship between food matrix and oral processing of food that may affect the sodium release (1st stage) and the delivery (2nd stage) is also discussed. In the 3rd stage, the food matrix affects the physical availability of sodium for the TRCs, the physiological activity of TRCs, and the central activities involved in the perception process. Based on the understanding of complex nature of the matrix effects on saltiness perception discussed in this review, the properties of food matrix may be controlled effectively to enhance saltiness perception and achieve sodium reduction.     

咸味感知与咸味肽的研究进展

随着生活水平的提高，人们的饮食习惯逐渐趋向“健康化”发展。如何平衡“健康”与“美味”的关系，调味这一加工环节至关重要。咸味是5种基本味觉之一，人们日常生活中主要通过添加食盐来达到增咸的目的。食盐在人类生活中发挥着重要的作用，但是过量的钠离子摄入会导致许多心血管疾病。在全球范围内，许多国家或地区的卫生组织均倡议低钠盐饮食，因此在不影响食品风味品质的前提下减少食盐添加量成为目前研究的一大热点。本文围绕咸味感知和减盐研究现状，重点针对咸味肽进行详细介绍，包括咸味肽的来源、制备、纯化鉴定、协同增效作用和应用前景，为咸味肽的开发和应用提供依据和支撑，推动减盐行动。     

黄金茶工夫红茶的甜味量化及其与主要滋味物质相关性分析

以黄金茶工夫红茶为研究对象,量化评价茶汤甜味强度,检测主要滋味物质含量,并分析两者相关关系。结果表明：不同厂家的黄金茶工夫红茶甜味强度差异明显;糖类甜味物质中麦芽糖含量最高,氨基酸类甜味物质中丝氨酸含量最高;甜味物质（包括单糖、双糖和甜味氨基酸）和茶氨酸含量均与甜味强度呈正相关,且糖总量与甜味强度呈显著（P＜0.05）正相关（r=0.781）;儿茶素、咖啡碱、没食子酸、茶黄素、茶红素含量与甜味强度呈负相关,且儿茶素总量、茶黄素含量与甜味强度呈显著（P＜0.05）负相关（r=－0.811和－0.781）,添加表没食子儿茶素没食子酸酯能降低糖类甜度。鉴于甜味是工夫红茶的分属滋味之一,甜味量化及相关性分析将为工夫红茶品质评判提供研究基础。     

pH和温度对8种甜味剂的甜味释放特征的影响

为探究pH和温度对8种不同甜味剂（蔗糖、果葡糖浆、麦芽糖醇、山梨糖醇、低聚果糖、甜菊糖苷00、甜菊糖苷07和甜菊糖苷14）甜味动态释放特征的影响规律,先通过成对比较法、量值估计法和单因素方差分析,确定了在常温中性条件下,与5 g/dL蔗糖甜度对等的其他7种甜味剂质量浓度。进一步通过时间-强度法（time-intensity）描绘了8种甜味剂在常温中性（25 ℃、pH 7.0）、常温酸性（25 ℃、pH 4.5）和低温中性（4 ℃、pH 7.0）3种条件下的甜味动态释放特征。结果表明,对于大部分样品而言,酸性和低温条件均会降低最大甜味强度,其中,酸性条件对果葡糖浆和甜菊糖苷类样品的降低效果高于低温条件,而对于糖醇类、蔗糖和低聚果糖等样品,低温条件降低效果更显著。此外,各样品的整体甜味持续时间也受到酸性和低温条件的抑制而缩短,且低温条件影响更显著。因此,酸性或低温条件都会抑制不同甜味剂的甜味释放强度或释放时间,但影响程度不同;相比而言,3种条件下,在甜味动态释放特征及变化趋势上,与蔗糖的表现最为接近的是山梨糖醇,其次是果葡糖浆和低聚果糖。     

Na+ Binding as Measured by 23Na Nuclear Magnetic Resonance Spectroscopy Influences the Perception of Saltiness in Gum Solutions

Binding of Na⁺ in aqueous gum systems as determined by ²³Na nuclear magnetic resonance (NMR) spectroscopy and its relations to perceived saltiness were examined. Two levels of NaCl (0.1% and 0.2%) were added to two concentrations (0.1% and 0.3%) of two ionic (xanthan and kappa carrageenan) and two non-ionic (locust bean and guar) gum solutions. Saltiness perception was affected by the ionic properties of the gums. NMR transverse relaxation rates (R₂, see^?l) indicated Na⁺ was less mobile in ionic than nonionic systems. Ionic gums correspondingly suppressed saltiness perception- compared to nonionic gums. As Na⁺ increased in both ionic and nonionic systems, R₂ values converged and perceived saltiness equalized. Food components that bind Na⁺ may suppress saltiness perception, which may be important in low-sodium foods.     

Improving the Palatability of Salt-Reduced Food Using Dried Bonito Stock

ABSTRACT:  The characteristic flavors, with the exception of umami, of dried bonito stock not only enhanced saltiness but also improved palatability, namely the acceptability, of salt-reduced foods. However, the respective effects of odorants and tastants of dried bonito stock on palatability have yet to be fully explained. Thus, the effect of dried bonito stock aroma on saltiness enhancement and palatability improvement in salt-reduced food was evaluated by sensory assessment. Probit analysis indicated that aromas of the stocks,  arabushi  and  karebushi , did not affect the intensity of saltiness. However, the test sample with aromas of dried bonito stocks was significantly more palatable than the reference sample. The effects of the taste of dried bonito stock were also evaluated. Probit analysis indicated that enhanced saltiness was not observed in the MSG solution but was observed with the dried bonito stocks, when controlled for aroma. These results suggest that saltiness enhancement by dried bonito stock was caused by the characteristic taste (excluding umami) of dried bonito stock, while its characteristic aroma and umami were involved in preventing the loss of palatability of a low-salt diet. Moreover, it was found that using a combination of  karebushi  and dried kelp, as material for making stock, could contribute effectively to the preparation of palatable salt-reduced foods in Japan. Invention of new seasonings for improving the palatability of salt-reduced foods could exploit these findings.     

基于大豆原料蛋白质和氨基酸组成的豆浆甜度预测模型研究

本研究采用电子舌分析了30个大豆品种加工成豆浆的甜度值,运用相关性分析法探究了豆浆甜度值与大豆原料蛋白、氨基酸组成之间的关系,使用逐步回归的方法建立了豆浆甜度的预测模型。结果表明:不同品种的大豆在蛋白质、氨基酸组成上有很大差异。大豆球蛋白(11S)含量(r=0.370)、大豆球蛋白/β-伴大豆球蛋白比率(11S/7S比率)(r=0.436)、丝氨酸(r=0.418)和苏氨酸(r=0.373)含量与豆浆甜度呈显著正相关(p<0.05),α亚基含量(r=-0.460)、β-伴大豆球蛋白(7S)含量(r=-0.428)、蛋氨酸(r=-0.372)和酪氨酸(r=-0.464)含量与豆浆甜度呈显著负相关(p<0.05)。通过逐步回归建立豆浆甜度预测模型的决定系数R²=0.747,方程为:F(甜度预测值)=-0.125×α亚基+3.172×苏氨酸+1.655×丝氨酸-2.894×蛋氨酸-2.097×酪氨酸+9.908,模型验证结果显示,实测值与模型预测值的平均相对误差为4.61%。因此,用本研究模型能准确地预测豆浆甜度。     

影响浓香型酒甜味因素的探讨

绵甜是浓香型大曲酒的主要特点。影响浓香型大曲酒甜味的因素有：（1）多元醇类、a-联酮类及醛类物质的量比;（2）发酵速度：曲和入窖温度;配料加入池酸度;（3）发酵周期;（4）原料、菌种及菌种数;（5）接酒操作;（6）白酒的贮存处理;（7）勾调处理等。     

甘薯甜度与薯块蒸煮前后糖分的相关性研究

测定了357个干率范围在17.26%～42.42%的甘薯育种选种圃群体蒸煮前后的还原糖、可溶性糖及其甜度。研究表明:甜度与熟薯的可溶性糖、还原糖、生薯可溶性糖呈极显著相关,相关系数分别为0.360**、0.277**0、.274**,与生薯还原糖没有明显相关性,其相关系数仅为0.039。对熟薯的可溶性糖进行分解研究表明,蒸煮过程中产生的还原糖和可溶性多糖对甜度的贡献率分别为47.66%、32.07%。按甜度分级的群体平均数分析,甜度同样与熟薯的可溶性糖、还原糖、生薯可溶性糖呈显著相关性,相关系数分别为0.977**、0.974**0、.962**,与生薯还原糖没有明显相关性,其相关系数仅为0.225。对上述糖分指标的群体分布研究表明,生薯还原糖、生薯可溶性糖、熟薯还原糖呈较窄的正态分布,而熟薯可溶性糖呈较宽的正态分布。综合分析得出,熟薯可溶性糖与甜度具有较高的相关性和品种间的差异,更适合作为甘薯甜度评价的指标和食用品种品质育种指标,甘薯的甜度主要来源于蒸煮过程中产生的糖分而非鲜薯糖分。     

2-(4-甲氧基苯氧基)丙酸钠甜味抑制剂在含糖食品中的应用

2-(4-甲氧基苯氧基)丙酸钠甜味抑制剂具有抑制多种糖类甜味的作用,用于含糖量较高的食品中调节甜度。本文介绍了甜味抑制剂在含糖食品中的应用,用量在万分之一到万分之五之间即可获得满意的抑甜效果。无须改变含糖食品原来的生产工艺,用法简单。     

Enhancement effect on apparent viscosity of aqueous tragacanth gum dispersions promoted by sugars

Flow curves of aqueous dispersions of tragacanth gum (T) with sucrose and glucose at different temperatures were determined using a controlled‐stress rheometer. The effect of sodium chloride without or with sucrose (at the highest content) on the rheology of T dispersions was evaluated. The presence of sucrose and glucose promoted a noticeable enhancement impact on the apparent viscosity of aqueous T dispersions, which depended on sugar type/content, shear rate and temperature. In all cases, the glucose addition led to the largest enhanced viscosities at low shear rates (<10 s^?1) and temperature. The joint action of sugar and salt exhibited a notable effect on apparent viscosity at low shear rates, softening the strong shear‐thinning behaviour of T samples. Flow curves of T in the presence of sugars were satisfactorily described by the Cross‐Williamson model, being semi‐empirical correlations of the model parameters with ingredients content and temperature stablished.     

水中Na~+浓度对绿茶茶汤滋味品质的影响及其内在原因分析

钠离子是饮用水中的重要金属离子,为探明其对绿茶茶汤滋味品质的影响,本文分析了不同浓度钠离子(0~200 mg/L)对普通绿茶茶汤滋味品质的影响及其内在原因。研究结果表明,添加外源钠离子(Na Cl)可以一定程度上影响普通绿茶茶汤的苦味、涩味和醇度等滋味强度;适量的钠离子(20 mg/L)可以有效降低普通绿茶茶汤的苦味和涩味强度、提高茶汤醇味程度,从而改善绿茶茶汤的整体滋味品质。通过分析,发现钠离子的添加对茶汤滋味品质成分的含量没有显著影响,而是通过改变儿茶素(EGCG)、咖啡碱和茶氨酸等主要滋味品质成分及其混合液的呈味特性来影响绿茶茶汤整体滋味品质。本研究还分析了不同阴离子钠盐对绿茶茶汤滋味品质的影响差异,结果发现氯化钠和硫酸钠对普通绿茶茶汤滋味品质的改善显著好于其他钠盐。本研究结果将为绿茶饮料的滋味品质调控提供理论基础。     

2-(4-甲氧基苯氧基)丙酸卤代衍生物的合成及其甜味抑制作用评价

为探究卤素取代对2-(4-甲氧基苯氧基)丙酸（2-(4-methoxyphenoxy) propionic acid，HPMP）甜味抑制特性的影响，通过对HPMP苯环的2位或3位进行卤素（F、Cl、Br）取代，合成6 种HPMP卤代衍生物并进行结构表征，采用电子舌评价其甜味抑制作用。结果表明：HPMP卤代衍生物可竞争性抑制甜味，在苯环的2位上引入卤原子的衍生物均存在明显的量效关系；6 种衍生物对蔗糖、果糖、葡萄糖、木糖醇和赤藓糖醇均能表现出一定的甜味抑制作用；氟代、氯代衍生物的甜味抑制活性较强，推测卤素取代基的尺寸及电负性大小可能是造成甜味抑制效果差异的关键因素。本研究表明卤素取代对HPMP发挥甜味抑制作用具有重要意义，从而为甜味抑制化合物的构效关系研究提供可靠的理论基础。