Developing a Lexicon for Descriptive Analysis of Soymilks

Soymilk stability increase using polyphenols microcapsules

Functional beverages have aroused a great interest to the food industry. Among the functional ingredients, there is a growing demand for antioxidant incorporation into foods, which implies a challenge to preserve their bioactivity. The health benefits provided by soymilk can be improved by the addition with microcapsules of polyphenols from peanut skin and this procedure is an alternative to protect these natural and bioactive compounds from environmental factors. The aim of this work was to determine the chemical, antioxidant, microbiological and sensory changes during storage of the product. Soymilk samples were prepared without any addition (C); with peanut skin extract (BEA); and with microcapsules with polyphenols (MCBEA) and stored at 4 °C for 30 days. Results showed that the addition of polyphenols (free or microencapsulated) improved the chemical, microbiological and sensory stability of soymilk. The BEA and MCBEA had lower values of hydroperoxides, hexanal, bacterial growth, oxidised flavour, and sweet taste than C. The BEA exhibited higher phenol content (819.72 mg gallic acid equivalents/L), antioxidant activity (64.66% DPPH inhibition) and colour intensity than MCBEA. The study suggested that polyphenol microencapsulation is a procedure that can protect these sensitive compounds and control their release into this food matrix.

Effects of aroma-taste interaction on the sensory attributes of rebaudiosides in soymilk and milk

BACKGROUND

Rebaudioside A (Reb-A) and rebaudioside M (Reb-M) are intense natural sweeteners but can also elicit bitterness and a bitter aftertaste. In this study, the effect of vanilla and chocolate flavorings on the sensory attributes of Reb-A and Reb-M applied to soymilk and milk was investigated to identify whether the addition of flavoring could enhance the sweetness via aroma-taste interactions.

RESULTS

Nine samples each of soymilk and milk were formulated by adding sucrose, Reb-A and Reb-M in three flavor conditions (no flavoring, vanilla, and chocolate). Descriptive analyses were conducted using nine panelists for the soymilk and eight panelists for the milk. Another descriptive analysis was conducted using the same samples with olfactory occlusion via the wearing of a nose clip to check whether the sweetness enhancement was due to olfactory input. The chocolate flavoring significantly enhanced the sweetness of Reb-A and Reb-M and reduced the bitterness, bitter aftertaste and astringency in both soymilk and milk. The vanilla flavoring was not as effective as the chocolate flavoring in enhancing sweetness. When the olfactory passage was closed with a nose clip, the sweetness enhancement and bitterness suppression were not detected in the samples.

CONCLUSION

The addition of chocolate flavoring could successfully improve the sensory profile of soymilk sweetened with Reb-A through aroma-taste interactions. © 2023 Society of Chemical Industry.

A Comparative Analysis of Plant-Based Milk Alternatives Part 1: Composition, Sensory, and Nutritional Value

Consumers are becoming increasingly interested in reducing the consumption of animal-based foods for health, sustainability, and ethical reasons. The food industry is developing products from plant-based ingredients that mimic animal-based foods’ nutritional and sensory characteristics. In this study, the focus is on plant-based milk alternatives (PBMAs). A potential problem with plant-based diets is the deficiency of important micronutrients, such as vitamin B12, B2, and calcium. Therefore, an analysis of micronutrients in PBMAs was conducted to assess their nutritional value. The second main focus was on the sensory description of the PBMAs, done by a trained panel, and instrumental assessment to characterize the sensory attributes. Almond drinks met the daily micronutrient requirements the least, while soy drinks came closest to cow’s milk in macro- and micronutrients. The experimentally determined electronic tongue and volatile compound results confirmed the sensory panel’s evaluations and could therefore be used as a method for easy and effective assessments of PBMAs. The PBMAs evaluated in this study could not completely replace cow’s milk’s nutritional and sensory properties. They are products in their own product group and must be evaluated accordingly. Given the variety of products, consumers should experiment and make their decisions regarding the substitution of cow’s milk.

Development of Nano Soy Milk through Sensory Attributes and Consumer Acceptability

Nanotechnology is currently applied in food processing and packaging in the food industry. Nano encapsulation techniques could improve sensory perception and nutrient absorption. The purpose of this study was to identify the sensory characteristics and consumer acceptability of three types of commercial and two types of laboratory-developed soy milk. A total of 20 sensory attributes of the five different soy milk samples, including appearance, smell (odor), taste, flavor, and mouthfeel (texture), were developed. The soy milk samples were evaluated by 100 consumers based on their overall acceptance, appearance, color, smell (odor), taste, flavor, mouthfeel (texture), goso flavor (nuttiness), sweetness, repeated use, and recommendation. One-way analysis of variance (ANOVA), principal component analysis (PCA), and partial least square regression (PLSR) were used to perform the statistical analyses. The SM_D sample generally showed the highest scores for overall liking, flavor, taste, mouthfeel, sweetness, repeated consumption, and recommendation among all the consumer samples tested. Consumers preferred sweet, goso (nuttiness), roasted soybean, and cooked soybean (nuttiness) attributes but not grayness, raw soybean flavor, or mouthfeel. Sweetness was closely related to goso (nuttiness) odor and roasted soybean odor and flavor based on partial least square regression (PLSR) analysis. Determination of the sensory attributes and consumer acceptance of soymilk provides insight into consumer needs and desires along with basic data to facilitate the expansion of the consumer market.

Descriptive sensory analysis of instant porridge from stored wholegrain and decorticated pearl millet flour cooked, stabilized and improved by using a low-cost extruder

Pearl millet flour, particularly wholegrain flour, is highly susceptible to development of rancid aromas and flavors during storage. Grain decortication and extrusion cooking using a friction-heated single-screw extruder were investigated as potential flour stabilization processes. Raw and extruded wholegrain and decorticated grain pearl millet flours were stored at ambient (25°C) and elevated (40°C) temperatures for 6 months. A trained descriptive sensory panel developed a lexicon of 44 attributes to profile the aroma, flavor, and texture of porridges prepared from the flours. Grain decortication alone did not show an effect on the aroma and flavor profile of porridge. Extrusion cooking of both wholegrain and decorticated flours increased cereal-like aromas (branny, canned sweetcorn, sweet, and wheaty) and flavor (starchy), as well as stiffness and cohesiveness of the porridges. The porridges from the extruded pearl millet flours stored for up to 6 months at ambient and elevated temperatures did not show any indications of rancidity. In contrast, rancidity-associated aromas (chemical, painty, and soapy) and flavor (chemical) increased in porridges from the raw flours stored for 4 weeks and longer. These results indicate that grain decortication did not sufficiently reduce fat content to prevent oxidation, while extrusion cooking stabilized the pearl millet flours. In addition, intensified "cereal-like" aromas and flavors were probably due to Maillard reactions occurring during extrusion cooking. Resulting aroma compounds could have been immobilized in the extruded matrix and not released during flour storage. The application of extrusion cooking with a simple friction-heated single-screw extruder is a viable process for both precooking and extending the shelf life of pearl millet flours. PRACTICAL APPLICATION: This study demonstrates the potential of extrusion cooking to precook wholegrain pearl millet while preventing fat rancidity in wholegrain pearl millet flour, thereby improving the sensory quality and stability of pearl millet food products. The extensive sensory characterization of pearl millet porridge-type foods can serve as a guidance tool for development, improvement, and quality control of pearl millet foods. Furthermore, it establishes the efficacy of simple friction-heated, single-screw extruders for commercial manufacture of ready-to-eat wholegrain pearl millet food products by small and medium scale entrepreneurs.

Standardized methods for testing the quality attributes of plant-based foods: Milk and cream alternatives

The food industry is creating a diverse range of plant-based alternatives to dairy products, such as milks, creams, yogurts, and cheeses due to the increasing demand from consumers for more sustainable, healthy, and ethical products. These dairy alternatives are often designed to mimic the desirable physicochemical, functional, and sensory properties of real dairy products, such as their appearance, texture, mouthfeel, flavor, and shelf-life. At present, there is a lack of systematic testing methods to characterize the properties of plant-based dairy alternatives. The purpose of this review is to critically evaluate existing methods and recommend a series of standardized tests that could be used to quantify the properties of fluid plant-based milk alternatives (milk and cream). These methods could then be used to facilitate the design of milk alternatives with somewhat similar attributes as real dairy milk by comparing their properties under standardized conditions. Moreover, they could be used to facilitate comparison of the properties of milk alternatives developed in different laboratories.

Utilizing Consumer Perception of Edamame to Guide New Variety Development

Consumption of edamame (vegetable soybeans) has increased significantly in the U.S. over the last 20 years. Although market demand has been increasing, most edamame is still imported from Asian countries. A team of multistate plant-breeding programs in the mid-Atlantic and Southeast U.S. has focused on developing new breeding lines that grow well in the U.S. and deliver what domestic growers, processors and consumers need and expect from their edamame. In our study, sensory evaluation was used to identify edamame genotypes and sensory attributes preferred by consumers to support breeding selection criteria. In the first year (reported as our “screening study”), 20 edamame genotypes were grown in three locations: Newport, AR, and Blacksburg and Painter, VA. In the second year (reported as our “validation study”), 10 edamame genotypes selected after our screening study were grown in Blacksburg and Painter, VA, Portageville, MO, and Stoneville, MS. In both years of research, untrained participants (adults; vegetable consumers not allergic to soy; N ≥ 50) used a traditional 9-point acceptability (hedonic) scale (1 = “dislike extremely”; 9 = “like extremely”) to evaluate overall-liking, aroma, appearance, taste, and texture, and a 5-point scale (1 = “not sweet,” 5 = “extremely sweet”) to evaluate sweetness intensity. Next, participants used a check-all-that-apply (CATA) list of selected sensory terms to describe the sensory characteristics of each edamame sample. Overall acceptability of edamame genotypes was significantly different among all genotypes (p < 0.05). Samples described as “bitter,” “sour” (flavor) or “starchy” (texture) were associated with lower acceptability scores while “salty” and “sweet” (flavor) were correlated with higher acceptability. Sensory data from the screening study were used to select the best genotypes by use of a defined decision process based on the consumer data. The validation study tested the selection decisions and further supported the genotype choices. Sensory evaluation is a powerful tool to direct breeders to improve market acceptability and develop new edamame genotypes. Both screening and validation studies illustrate the significant role of consumer sensory data in support of genotypes targeted for domestic (U.S.) production.

What is lost in translation: A cross-cultural study to compare the concept of nuttiness and its perception in soymilk among Korean, Chinese, and Western groups

Cross-cultural communication of "nuttiness" can be problematic because the underlying conceptual elements and words used to describe its features may be largely culture-dependent. The present study was conducted to understand similarities and dissimilarities in the concept of nuttiness and its actual perception in our model food system, soymilk, among similar (Korean and Chinese) and dissimilar (Western) food cultures. In total, 110 Koreans, 103 Chinese, and 93 English-speaking, Western consumers were recruited. Subjects were asked to provide a definition of nuttiness and generate examples of nutty and non-nutty foods. They also rated the intensity of the nuttiness of 8 soymilk samples. Sensory profiles of 8 soymilk samples were obtained using 9 trained panelists. Data from the definition task were processed through textual analysis. To identify sensory drivers, consumer ratings of perceived nuttiness intensity in soymilk were projected onto a sensory space constructed from the descriptive profiles of nuttiness. We found significant association between culture and usage of specific words (χ²_{70, 0.05}=155.8, p<0.001). For example, whereas the concept of nuttiness in the Korean group involved sensory experiences evoked by sesame, roasted, proteic, or fatty foods, in Westerners, it was more nut-oriented. In contrast, the Chinese group associated nuttiness with general characteristics and hedonic dimensions such as good and comfort, rather than with specific foods. However, sensory drivers of nuttiness in soymilk were consistent across cultures. We found that although the abstract definition of nuttiness clearly demonstrated cross-cultural differences, sensory perception of nuttiness was almost identical across all groups. This suggests that cultural background influences verbalization of one's perception, but not the actual perception itself.

Flavor characteristic analysis of soymilk prepared by different soybean cultivars and establishment of evaluation method of soybean cultivars suitable for soymilk processing

Flavor is an essential quality characteristics of soymilk, which contains volatile compounds derived from fatty acids via enzymatic and thermal reactions. In this study, 67 kinds of soybean cultivars were selected, and correlation analysis was conducted between physicochemical indexes of these soybean cultivars and flavor characteristic indexes of soymilk. With clustering analysis, all the soybean cultivars could be classified into three classes, and according to the results of principal component analysis for each class of soymilk flavor characteristics, the soymilk of second class had relatively heavier beany and non-beany flavor, and the third class had weaker flavor. For soybean cultivars of which the soymilk characteristics were unknown, two discriminant functions could be used to predict flavor characteristics if the physicochemical indexes were known. Therefore, screening of soybean cultivars suitable for soymilk processing can be targeted for the flavor favored by consumers and an evaluation method established.

Effect of hydrocolloid on rheology and microstructure of high-protein soy desserts

Due to the rheological and structural basis of texture perceived in semisolid foods, the aim of this work was to study the effects of two thickening agents, on rheology and microstructure of soy protein desserts. As rheological parameter values may not be enough to explain the possible perceived texture differences, the effect of composition on two instrumental indexes of oral consistency (apparent viscosity at 50 s(-1) and complex dynamic viscosity at 8 Hz) was also studied. Samples were prepared at two soy protein isolate (SPI) concentrations (6 and 8 % w/w), each with four modified starch concentrations (2, 2.5, 3 and 3.5 % w/w) or four Carboxymethyl cellulose (CMC) concentrations (0.3, 0.5, 0.7 and 0.9 % w/w). Two more samples without added thickener were prepared as control samples. The flow curves of all systems showed a typical shear-thinning behaviour and observable hysteresis loops. Control sample flow fitted well with the Ostwald-de Waele model and the flow of samples with thickener to the Herschel-Bulkley model. Viscoelastic properties of samples ranged from fluid-like to weak gel, depending on thickener and SPI concentrations. Starch-based samples exhibited a globular structure with SPI aggregates distributed among starch granules. In CMC-based samples, a coarse stranded structure with SPI aggregates partially embedded was observed. Variation of the two thickness index values with composition showed a similar trend with good correlation between them (R(2) = 0.92). Soy desserts with different composition but with similar rheological behaviour or instrumental thickness index values can be obtained.

Development of soy-based bread with acceptable sensory properties

Consumption of soy protein has been associated with benefits related to numerous areas of health. Due to the widespread consumption of bread, one means of contributing to the health of individuals is through the incorporation of soy protein into bread. To this end, soy flour (SF) or soy protein isolates (SPIs) in 20% and 12% substitution levels, respectively, were added to flour during bread manufacture. The developed breads were tested using a consumer panel for acceptability, using a refined white bread as a control. These data were compared to attribute intensity data collected by the trained panel to identify specific flavor and texture characteristics affecting liking. The sensory profile of the 20% SF bread was acceptable and comparable to the control bread, despite a significantly stronger beany flavor. No significant differences in sensory properties of the SF and control breads were detected by the trained panel for many sensory attributes. The SPI bread, however, had a sensory profile that was significantly more firm, dense, sour, beany, bitter, and astringent with a strong aftertaste in comparison to the wheat control bread. Consumer liking scores for the SPI bread was significantly lower than the liking of the control and the SF added bread.

PRACTICAL APPLICATION

Many soy-enriched foods, while contributing positively to health, are considered unacceptable by consumers. This is due to negative sensory properties, such as beany, painty, and astringent notes, often perceived by consumers. This study provides information on the level of SF that can be included in bread in an amount that does not detract from consumer acceptability. This level also allows for a Food and Drug Administration (FDA) health claim to be made.

Flavor lexicon for sensory descriptive profiling of different rice types

Rice flavor is a significant factor in determining quality and consumer acceptability as exemplified by scented rice, which is highly favored and commands a price premium. Sensory descriptive analysis has primarily been performed to assess rice flavor characteristics, but these studies feature only a limited lexicon for characterizing specific flavors or the range of flavor types is limited. This study was undertaken to establish a descriptive lexicon with reference standards for describing the flavor properties of a broad spectrum of rice types and use the developed lexicon to characterize which sensory attributes are most important in rice flavor quality. A rice flavor lexicon consisting of 24 descriptive notes was developed and expanded by 8 trained sensory panelists to characterize the flavor of cooked rice differing in terms of forms, types, and specialty (n = 36). Of these 24 descriptive terms, 19 were aromatic notes and 5 were fundamental tastes and oral feeling factors. Eighteen aromatic terms were significantly present in most rice samples whereas some descriptors exhibited unique characteristics of a specific-rice type. Subsequent multivariate analysis indicated that 18 descriptive terms were required to fully understand the characteristics of rice flavor in greater details. This lexicon covered a wider range of rice samples than in the previous studies and will facilitate targeting the characteristic notes important to rice processors as well as producers.

Acceptability of Milk and Soymilk Vanilla Beverages: Demographics Consumption Frequency and Sensory Aspects

Acceptance of food is basically the result of the interaction between food and humans, and it depends not only on the product characteristics but also on those of each consumer. The main objective of this study is to analyze how the acceptability of milk and soymilk vanilla beverages is influenced by demographic characteristics, consumer habits and individual preferences, and the sensorial properties of both products. Six commercial samples, comprising three milk beverages and three soymilk beverages of different brands and characteristics, were sensorially evaluated. Overall acceptability was tested by 142 consumers using a 9-point hedonic scale, and 36 assessors ranked the samples from the least to the most intense according to their yellow color, brightness, vanilla flavor intensity, sweetness, and thickness. The milk samples were significantly (P<0.05) more acceptable than the soymilk ones and were perceived as being stronger yellow and less light in color, with a more intense sweetness, stronger vanilla flavor, and thicker consistency. The results obtained led us to the conclusion that the difference in acceptability between milk and soymilk beverages is more closely related to their sensorial attributes than to other characteristics (demographic, consumer habits, and individual preferences) of the consumer population surveyed.

Characterization of Dried Whey Protein Concentrate and Isolate Flavor

The flavor of whey protein concentrates (WPC 80) and whey protein isolates (WPI) was studied using instrumental and sensory techniques. Four WPC 80 and 4 WPI, less than 3 mo old, were collected in duplicate from 6 manufacturers in the United States. Samples were rehydrated and evaluated in duplicate by descriptive sensory analysis. Duplicate samples with internal standards were extracted with diethyl ether. Extracts were then distilled to remove nonvolatile material using high vacuum distillation. Volatile extracts were analyzed using gas chromatography/olfactometry with post peak intensity analysis and aroma extract dilution analysis. Compounds were identified by comparison of retention indices, odor properties, and gas chromatography/mass spectrometry against reference standards. Whey proteins exhibited sweet aromatic, cardboard/wet paper, animal/wet dog, soapy, brothy, cucumber, and cooked/milky flavors, along with the basic taste bitter, and the feeling factor astringency. Key volatile flavor compounds in WPC 80 and WPI were butanoic acid (cheesy), 2-acetyl-1-pyrroline (popcorn), 2-methyl-3-furanthiol (brothy/burnt), 2,5-dimethyl-4-hydroxy-3-(2H)-furanone (maple/spicy), 2-nonenal (fatty/old books), (E,Z)-2,6-nonadienal (cucumber), and (E,Z)-2,4-decadienal (fatty/oxidized). This baseline data on flavor and flavor sources in whey proteins will aid ongoing and future research and will help to identify the most appropriate whey ingredients to use to control or minimize flavor variability in whey enhanced products.