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.     

Retronasal Odor of Dried Bonito Stock Induces Umami Taste and Improves the Palatability of Saltiness

A traditional Japanese umami‐rich stock, dried bonito stock, was reported to improve the palatability of a low‐salt diet due to its characteristic aroma. Two pathways are available for the presentation of odors: the orthonasal and retronasal pathways. Aroma is perceived through the orthonasal pathway. In contrast, retronasal application of odors is thought to evoke different sensations from the orthonasal pathway, which is typically perceived as taste and modifies taste. Therefore, the effect of retronasal odor on salt‐reduction might be different from that of aroma, that is, orthonasal odor. Thus, the effects of the retronasal odor of dried bonito stock on the enhancement and improvement of palatability upon salt reduction were examined using sensory evaluation. Moreover, the contributions to flavor expression and palatability of dried bonito stock were also investigated. Although the retronasal odor of dried bonito did not enhance saltiness, it improved the palatability of saltiness. In the presence of no tastants except 0.68% NaCl, a content 15% less than that of Japanese traditional soup, the retronasal odor of dried bonito generated umami, enhanced the suitability for dried bonito stock, and increased palatability. This indicates that the retronasal odor of dried bonito stock could improve the palatability of a salt‐reduced diet. These findings can be applied to the development of new seasonings for improving the palatability of salt‐reduced foods.     

Interactions of Monosodium Glutamate and Sodium Chloride on Saltiness and Palatability of a Clear Soup

The sensory interactions of monosodium glutamate (MSG) and NaCl in a clear soup were examined by a sensory test, by a response-surface method. The extents of saltiness and palatability were expressed by second order polynomials of the concentrations of MSG and NaCl added. The polynomials indicated that to provide an appropriate saltiness and the maximum palatability score, more NaCl was required in soup with a lower MSG concentration, and vice versa. It is recommended that when the amount of sodium in the soup must be restricted while retaining a high palatability score, the NaCl level should be reduced while adding an optimal MSG level.     

Analysis of binary taste-taste interactions of MSG,lactic acid,and NaCl by temporal dominance of sensations

Temporal dominance of sensations (TDS) is a relatively novel sensory evaluation technique that measures the temporal evolution of sensory perception. The sensory properties of food or drink products have been described by TDS; however, basic sensory data on TDS are still lacking. We analyzed TDS data for solutions of three basic tastes (umami, salty, and sour) and their binary combinations. The duration of TDS for the main taste of each type of solution (monosodium glutamate [MSG] for umami, sodium chloride [NaCl] for saltiness, and lactic acid for sourness) increased in a concentration-dependent manner. In addition, the duration of the umami taste of MSG was longer than that of MSG/inosine 5′-monophosphate solution with an umami taste of equivalent intensity. The duration of NaCl saltiness was increased by coexistence with MSG and decreased by coexistence with lactic acid. On the other hand, the duration of the umami taste of MSG was suppressed by coexistence with NaCl but not lactic acid, while the duration of the sour taste of lactic acid was suppressed by MSG but not NaCl. These findings provide novel insight into the temporal sequence of basic taste perception during food consumption.     

香菇鸡蛋羹工业化生产配方优化及凝胶特性研究

以鸡蛋和香菇粉为主要原料,通过单因素结合响应面试验考察了水的添加量、蔗糖的添加量、香菇粉添加量对香菇鸡蛋羹感官品质的影响,利用质构仪、DSC(差式热量扫描仪)、RVA(快速粘度分析仪)研究未添加蔗糖和香菇粉、只添加香菇粉、只添加蔗糖、同时添加蔗糖和香菇粉的四种蛋羹的凝胶特性的变化。实验结果表明,当水添加量为173.28%、蔗糖添加量为4.04%、香菇粉添加量为1.57%(均以蛋液质量为基准),香菇鸡蛋羹感官品质预测最佳得分为88.94分,验证实验感观评分为90分。同时添加蔗糖和香菇粉显著增强香菇鸡蛋羹的硬度和咀嚼性,热焓值最大,凝胶强度也最大,研究结果表明蔗糖和香菇粉同时添加对香菇鸡蛋羹的凝胶强度具有增效作用。这为香菇鸡蛋羹的工业化生产奠定了一定的理论基础。     

The perceived saltiness of soup affected by tasting protocols

The objective of this study was to investigate the effect of tasting protocols on perception of saltiness in two different soup systems, soybean-sprout soup and chicken soup, containing six different levels of salt, respectively. One hundred participants evaluated the level of saltiness with the just-about-right (JAR) scales for the soup samples using two different tasting protocols: a beaker-tasting protocol (BTP) and a spoon-tasting protocol (STP). The results indicated that the sample tasting protocol significantly (P < 0.01) affected the perception of saltiness in both soup systems. The optimum NaCl concentrations determined by BTP were lower than those determined by STP in both soup systems. These findings emphasize the importance of sample presentations and tasting protocols in sensory tests to determine optimum levels of ingredients in food products.     

The effect of the pungent sensation elicited by Sichuan pepper oleoresin on the sensory perception of saltiness throughout younger and older age groups

Excessive salt in the diet can pose significant health risks and, therefore, the reduction of salt derived from food is an important issue relating to human nutrition and health. Furthermore, the perception of saltiness will be different among people when considering their innate sensitivity, gender, age, psychological traits and dietary habits. In this study, 31 younger participants and 29 older participants were used as research subjects. A web-based questionnaire survey was used to collect information regarding of socio-demographics, consumption frequency and liking for salty and pungent food, as well as personality traits throughout the younger and the older participants. In addition, the 6-n-propylthiouracil (PROP) ratings were tested by the generalized Labeled Magnitude Scale (gLMS) in the laboratory conditions. The rated difference from control method was used to test the sensitivity differences in the saltiness of NaCl and the pungent sensation elicited by Sichuan pepper oleoresin between the younger and older groups. The results showed that the thresholds were significantly lower in the younger group than in the older group, except for the detection threshold of saltiness. Furthermore, the recognition threshold of saltiness  decreased in the presence of the sub-threshold pungency solution, while, the salty intensity was enhanced in both the younger and older groups when exposed to the slightly pungent solution (0.106 g Sichuan pepper oleoresin/L water solutions) compared to the control (spring water). For the younger group, the enhancement percentage of the salty intensity was between 9.3% and 12.5%, while, at the concentration of 4.05 g/L, the salty-enhancement percentage increased by 6.4% in the older group. In addition, the reduction percentage of NaCl reached a level of up to 34.4% in the younger group and was 4.4% in the older group. The Partial Least Squares Regression (PLSR) results indicated that the percentage change in salty intensity increased when the detection threshold of saltiness, the sensation seeking ratings, and PROP ratings increased. On the contrary, the change decreased when the age, life satisfaction ratings, detection threshold of pungency, and consumption frequency of salty food increased. These findings not only provide new information for the flavor design of salt-reduced food and dishes, but also be valuable to public health as well as economic benefits.     

THE EFFECT OF FAT CONTENT AND FLAVOR ENHANCERS ON THE PERCEIVED SALTINESS OF COOKED 'BOLOGNA-TYPE' SAUSAGES

The effect of varying fat content (8, 12, 16, 20, 24 and 28%) on sausage perceived saltiness was studied using two different formulations, each with 1.2 and 2.0% NaCl. The formulations were made either by varying the proportions of lean pork and pork fat (Series 1) or by replacing water with pork fat on an equal weight basis (Series 2). The replacement of lean pork with pork fat increased the perceived saltiness of the sausages. When water was replaced with pork fat on an equal weight basis the perceived saltiness of the sausage, however, did not change. There was a strong negative correlation (P<0.01) between perceived saltiness and protein content thus suggesting a causative link between these factors. The flavor-enhancing properties of monosodium glutamate (MSG) and Ribotide (monosodium glutamate and 5'-ribonucleotides IMP and GMP) were also studied. MSG only slightly improved the sensory properties of the cooked sausages.     

Reducing salt content in beef frankfurter by edible coating to achieve inhomogeneous salt distribution

High dietary salt (NaCl) intake is a global health concern which leads to various chronic diseases; hence, the reduction of salt content in foods has been a high demand in the food industry. Inhomogeneous salt distribution is a promising strategy for salt reduction. This study investigated the effect of inhomogeneous salt distribution using salt edible coating on the physiochemical and sensory attributes of beef frankfurter sausages. Results demonstrated that this method significantly reduced the salt content in frankfurter sausages by 60–81% without affecting the consumers’ perception of saltiness intensity. Among the coated samples, 7.5% and 10% salt coating samples showed the best performance on the product quality. However, the problems associated with high cooking loss and hard texture of the salt-coated sausages need to be further addressed. This research has potentially developed a new method for manufacture of salt-reduced food.     

Potential of Szechuan pepper as a saltiness enhancer

The flavor profile, flavor enhancement, and saltiness modulation of Szechuan pepper (Zanthoxylum simulans) were analyzed to evaluate its effectiveness in lowering salt usage. The saltiness enhancing efficiency of Szechuan pepper and its salt-reduction properties were determined to be 28.74% and 22.32%, respectively. The saltiness enhancers were detected in the polar fraction and taste dilution analysis combined with half-tongue test determined the most potent saltiness enhancing components in chromatographic subfractions. Both spectroscopic analysis and sensory evaluation disclosed NaCl as the unexpected primary contributor of saltiness enhancement in this spice. It is the first known study revealing Szechuan pepper’s high salt content.     

Using Fish Sauce as a Substitute for Sodium Chloride in Culinary Sauces and Effects on Sensory Properties

Historically, fish sauce has been a standard condiment and ingredient in various Southeast Asian cuisines. Moreover, fish sauce imparts umami taste, which may enhance perceived saltiness in food. This quality suggests that fish sauce may be used as a partial substitute for sodium chloride (NaCl) in food preparation, which may present a valuable option for health‐conscious and salt‐restricted consumers. However, the degree to which NaCl can be decreased in food products without compromising taste and consumer acceptance has not been determined. We hypothesized that NaCl content in food may be reduced by partial replacement with fish sauce without diminishing palatability and consumer acceptance. Preparations of 3 types of food were assessed to test this hypothesis: chicken broth (n = 72); tomato sauce (n = 73); and coconut curry (n = 70). In the first session, the percentage of NaCl that could be replaced with fish sauce without a significant change in overall taste intensity was determined for each type of food using the 2‐Alternative Forced Choice method. In the second session, subjects rated 5 samples for each food with varying NaCl and/or fish sauce content on 3 sensory attributes: deliciousness; taste intensity; and saltiness. Our results demonstrate that NaCl reduction was possible in chicken broth, tomato sauce, and coconut curry at 25%, 16%, and 10%, respectively, without a significant loss (P < 0.05) in deliciousness and overall taste intensity. These results suggest that it is possible to replace NaCl in foods with fish sauce without reducing overall taste intensity and consumer acceptance.     

Salt (NaCl) reduction in cooked ham by a combined approach of high pressure treatment and the salt replacer KCl

The food industry must develop effective methods to address the reduction of salt in meat products and contribute to the reduction of salt consumption associated with cardiovascular diseases. This paper investigated the effect of NaCl content (0, 0.95, 1.33 and 1.90%), phosphate content (0 and 0.25%) and the use of high pressure processing (HPP) (100, 300, 600 MPa) at different processing stages (raw material, after injection, tumbling and cooking) on the quality parameters (cooking loss, texture, water holding capacity, color and saltiness perception) in cooked ham. The application of HPP to the raw meat or after its injection was detrimental to the structure and water retention of the salt-reduced cooked ham. Whereas the application of HPP at 100 MPa after tumbling was beneficial. A further salt reduction up to 1.1% NaCl was possible by the salt replacement with KCl (0.2%) in combination with the HP treatment.Industrial relevanceHigh-pressure treatment can help in the production of salt-reduced meat products but efforts are needed to understand the feasible levels of NaCl, phosphates and specific HP treatments to apply in commercial scenarios. The present paper describes a strategy to produce a salt-reduced cooked ham (45% reduction) using a HP treatment at 100 MPa after tumbling stage in combination with KCl (0.2%).     

A salt substitute with low sodium content from plant aqueous extracts

The perception of the salty taste, obtained in humans by using sodium chloride (NaCl), is one of the most important attributes of the human sensory system. However, extra intake of sodium present in salt might lead to conditions such as hypertension. To develop a salt substitute with low sodium content, 13 plants were extracted with water, and their sensory perception was analyzed. After the sensory evaluation, 3 plant aqueous extracts (PAEs), representing salty and umami tastes, were selected using principal component analysis (PCA). They were powdered using a spray dryer, mixed, and subsequently referred to as plant salt substitute (PSS). The relative saltiness of PSS to NaCl was shown to be 0.65. When the degree of saltiness between PSS and NaCl is the same, PSS contains 43% less sodium than NaCl. Therefore, PSS can be used in food to reduce an individual's sodium intake while retaining the salty taste of NaCl.     

Salt Reduction in Foods Using Naturally Brewed Soy Sauce

ABSTRACT:  In recent years, health concerns related to salt/sodium chloride consumption have caused an increased demand for salt-reduced foods. Consequently, sodium chloride (NaCl) reduction in foods has become an important challenge. The more so, since a decrease in NaCl content is often reported to be associated with a decrease in consumer acceptance. The objective of the present study was to investigate whether or not it would be possible to reduce the NaCl content in standard Western European foods by replacing it with naturally brewed soy sauce. Three types of foods were investigated: salad dressing ( n  = 56), soup ( n  = 52), and stir-fried pork ( n  = 57). In the 1st step, an exchange rate (ER) by which NaCl can be replaced with soy sauce without a significant change in the overall taste intensity was established per product type, by means of alternative forced choice tests. In the 2nd step, the same consumers evaluated 5 samples per product type with varying NaCl and/or soy sauce content on pleasantness and several sensory attributes. The results showed that it was possible to achieve a NaCl reduction in the tested foods of, respectively, 50%, 17%, and 29% without leading to significant losses in either overall taste intensity or product pleasantness. These results suggest that it is possible to replace NaCl in foods with naturally brewed soy sauce without lowering the overall taste intensity and to reduce the total NaCl content in these foods without decreasing their consumer acceptance.
PRACTICAL APPLICATION: Health concerns related to salt consumption cause an increased demand for salt-reduced foods. Consequently, the development of foods with reduced salt content without decreasing the consumer acceptance is an important challenge for the food industry. A new possible salt reduction approach is described in the present article: The replacement of salt with naturally brewed soy sauce.     

Identification and sensory evaluation of flavour enhancers in Japanese traditional dried herring (Clupea pallasii) fillet

Flavour-enhancing components of dried herring fillet (migaki-nishin in Japanese) were isolated and evaluated for their effects on sensory perception. Sensory evaluation revealed that addition of dried herring fillet water-soluble extracts to Japanese noodle soup significantly (P < 0.05) enhanced soup flavour characters, such as thickness, mouthfulness and continuity. The extracts were fractionated by dialysis and chromatography. Fractions containing flavour enhancers were isolated by sensory perception. Results from instrumental analyses showed that the kokumi flavour enhancers in dried herring fillet were creatine and creatinine.     

COMPARISON OF PUDDING, SOUP AND CUSTARD PREPARED FROM SOYMILK OR LOWFAT MILK

Soymilk (4% and 6% solids) was substituted for lowfat milk in chocolate pudding, tomato soup and baked egg custard. The substitution of soymilk produced a less viscous pudding that was darker in color and less sweet than that made with lowfat milk. Pudding prepared with 6% solids soymilk was also less smooth than the control. In tomato soup, soymilk increased viscosity and produced a lighter color product with a less intense tomato flavor than soup made with lowfat milk. Baked custard prepared with soymilk was less smooth, darker in color and less sweet. All products were judged to have less characteristic flavors than controls.