Salty, sweet, umami, and sour are the four fundamental tastes that constitute the framework of food flavor. Salt, sugar/sweeteners, soy sauce and umami compound seasonings, and vinegar-based sour seasonings are the core basic raw materials for industrial seasoning and catering formulas. Most practitioners rely solely on subjective taste judgments to assess the quality of raw materials, lacking standardized classification cognition and standardized tasting methods. This often leads to issues such as formula imbalance, incorrect raw material selection, and batch-to-batch flavor variation.

Based on current national standards such as GB 2721-2015 "National Food Safety Standard - Edible Salt", GB/T 5461-2016 "Edible Salt", GB 2760-2024, GB/T 18186-2025 "Brewed Soy Sauce", GB 2719-2018 "Vinegar", and GB/T 10221-2021 "Sensory Analysis - Terminology", this article systematically sorts out the four basic condiment subcategories, their physicochemical and flavor characteristics, and provides a standardized sensory evaluation operation procedure.

1. Edible salt: Savory base, category division, and physicochemical characteristics of flavor

Edible salt is a basic condiment with sodium chloride as its core flavor-presenting substance. According to the national standard GB 2721-2015, it is defined as a salt product with sodium chloride as its main ingredient, specifically for edible purposes. The industry generally adheres to the grading and classification standards outlined in GB/T 5461-2016.

(1) Classification based on raw materials and processing techniques, as well as core characteristics

Refined salt

Using sea salt, lake salt, and well-mined salt brine as raw materials, it is produced through vacuum evaporation, multiple purification processes, and crushing and drying, with a sodium chloride content of ≥99.1%. The particles are fine and uniform, with high whiteness and extremely low impurities. The salt tastes pure and clean without any off-flavor, dissolves quickly, and is suitable for liquid seasonings, marinades, baking, and instant products. However, its disadvantage is that it has extremely low mineral content and a bland flavor, lacking depth when used alone.

Crushed washing salt

Natural crude salt undergoes crushing, washing to remove impurities, and drying processes, resulting in a sodium chloride content of 97% to 99%, with a small amount of natural mineral components retained. It has a strong salty taste with a slight mineral undertone and uneven particle size, making it suitable for meat product marination, as a base salt for brine, and as a bulk condiment for catering.

Solar salt (coarse sea salt/lake salt)

Made through natural solar evaporation of brine, the resulting crystals are coarse and contain trace amounts of potassium, magnesium, calcium, and other ions. It boasts a rich layered salty taste, infused with a subtle freshness reminiscent of natural seawater or salt lakes. Due to its slow dissolution rate, it is not suitable for liquid compound seasonings and is predominantly used in air-dried meat products, barbecue sprinkles, and as a base for pickle fermentation.

Specially modified edible salt

Low-sodium salt: It partially replaces sodium chloride with potassium chloride, reducing the sodium content by 20% to 30%. It has a mild salty taste with a slightly bitter aftertaste of potassium. It is suitable for low-sodium healthy food formulas and requires control of the addition ratio to mask metallic off-flavors;

Flavor compound salt: Added with spice extract and yeast extract, it combines salty taste and complex aroma, and is mostly used in ready-to-eat meals and compound sprinkles;

Snowflake salt: Special recrystallization process, flaky loose crystals, fast dissolution rate, suitable for low-temperature cold drinks and cold dressing seasonings.

(II) Classification based on iodine addition properties

There are two types of salt: iodized salt and non-iodized salt. Iodized salt is suitable for general food processing, while non-iodized salt is specifically used for fermented soy products and pickled vegetables (iodine inhibits microbial fermentation).

(III) General sensory judgment points

According to the sensory requirements of the national standard: the color should be white and pure, with a salty taste, free from bitter, metallic, or earthy odors, and no visible impurities; crude salt is allowed to have trace amounts of natural mineral deposits, and should be free from moldy or damp-rotten smells.

II. Carbohydrates and Sweeteners: Classification, Flavor, and Application Characteristics of Sweetening Systems

Sweet ingredients are categorized into two major systems: nutritive sugars (basic food ingredients) and non-nutritive sweeteners (food additives, regulated under GB 2760-2024). These two systems exhibit significant differences in sweetness, thermal stability, aftertaste, and metabolic characteristics.

(1) Nutritional natural sugars (basic sweetening ingredients)

Sucrose (white granulated sugar, soft white sugar, brown sugar)

The sweetness benchmark is set at 100, with a balanced sweetness, a gentle release of sweetness, and no unpleasant aftertaste. It serves the dual purpose of enhancing freshness, balancing saltiness and acidity, and improving the roundness of flavor. White granulated sugar has high purity and light color, making it suitable for beverages and baking. Soft white sugar has fine particles and high moisture content, making it suitable for fillings. Brown sugar contains trace amounts of caramel components, with a natural caramel-like aroma, making it suitable for braised dishes and stewing seasonings. Prolonged cooking at high temperatures can easily lead to the Maillard reaction, producing a caramel aroma.

Glucose, fructose syrup

Glucose has a sweetness level of 70, with a prominent cool and sweet taste and strong moisturizing properties. High fructose corn syrup has a high proportion of fructose, with a sweetness level of 110~130, and its sweetness is more prominent at low temperatures, making it suitable for cold drinks and beverages. Both have high osmotic pressure and possess anti-corrosion and water retention functions, making them widely used in compound seasonings and sauces.

Maltose, maltose syrup

With a sweetness level of only 30~40, it offers a mild and rich sweetness without any sharpness. It carries a natural malt caramel aroma and excels in thickening and moisturizing. It is ideal for use in meat product marinades and braised compound sauces, where it helps to balance the salty and sour sensations.

(II) Non-nutritive sweeteners (permitted for use according to national standards, low/zero calorie)

Sugar alcohols (naturally low sweetness)

Xylitol, erythritol, and sorbitol, with a sweetness of 50% to 90% of sucrose, offer a refreshing sweetness without metabolic burden. They are heat-resistant and do not participate in Maillard browning, making them suitable for sugar-free sauces and cold dressing seasonings. Erythritol almost has no aftertaste and can synergistically mask spicy and astringent flavors.

Natural high-potency sweetness extract

Stevia glycosides (250-450 times sweeter), Arhat sweet glycosides (300 times sweeter), sourced from plants, with a mild herbaceous aftertaste, suitable for clean label seasonings, and need to be paired with sugar alcohols to mitigate the bitterness.

Artificially synthesized high-intensity sweeteners

Acesulfame potassium, sucralose, sodium cyclamate, and aspartame have sweetness levels ranging from 30 to 8000 times that of sugar, and a small amount can achieve a high sweetness effect; sucralose has excellent thermal stability and is suitable for high-temperature braising and baking seasonings; aspartame is not heat-resistant and is only used for room temperature liquid seasonings; synthetic sweeteners generally have a bitter taste after the threshold, and their defects can be offset by compounding.

(III) Summary of core flavor characteristics

Nutritional sugar can synergistically enhance the fresh and fragrant flavors, imparting the product with a mellow and rich taste; high-intensity sweeteners only provide a single sweetness, without enhancing or blending flavors, and excessive use can lead to issues such as sharp sweetness, aftertaste bitterness, and fragmented flavors.

III. Soy sauce and umami seasonings: categories, characteristics, and standardized sensory evaluation

Umami is the core flavor dimension of condiments. Brewed soy sauce serves as a complex umami base, supplemented by umami-enhancing ingredients such as hydrolyzed vegetable protein, yeast extract, and flavor-enhancing nucleotides. The complete umami system encompasses two major categories: fermentation-based and compound umami-enhancing. The tasting criteria are implemented in accordance with GB/T 18186-2025 and the group standard T/CNFIA 213-2024, "Guidelines for Sensory Evaluation of Condiments (Soy Sauce)".

(1) Subdivided categories and flavor characteristics of brewed soy sauce

High-salt liquid-state fermented soy sauce

Soybeans and wheat undergo long-term room temperature dilute-state fermentation, resulting in the production of light soy sauce and light-taste soy sauce. These products exhibit a light reddish-brown color, with a rich and intense aroma of soy sauce and esters. They possess a balanced fresh and sweet taste, with a distinct aftertaste and a high content of amino acid nitrogen. The fermentation process generates a large amount of complex flavor compounds, creating a delicate layering that is ideal for cold dishes, dipping sauces, and lightly seasoned dishes.

Low-salt solid-state fermented soy sauce

Short-cycle heated solid-state fermentation results in a dark brownish-red color, with prominent sauce aroma and slightly weak ester aroma. The freshness is high but the aftertaste is insufficient, with a stronger salty flavor. The cost is lower, making it suitable for braised dishes, marinated dishes, and high-temperature compound sauces.

Dark soy sauce / thick soy sauce

Using low-salt solid soy sauce as the base, caramel color is added to create a rich and hanging wall color. The freshness is average, with the core function of coloring, and it is mostly used in Braised pork belly products.

Sweet soy sauce (compound brewing)

During the fermentation process, white sugar and maltose are added to achieve a balance between sweetness and freshness, with a gentle caramelized sweetness. It is suitable for compound seasoning in Yunnan, Guizhou, Sichuan cold dishes and braised dishes.

(II) Other mainstream umami seasoning categories

Blended soy sauce

With brewed soy sauce as the main ingredient, compounded with acid hydrolyzed vegetable protein seasoning liquid, the freshness is enhanced, but the natural fermentation sauce aroma and ester aroma are significantly weakened. The cost is low, and it is mostly used in industrial large-scale compound seasoning sauce.

Hydrolyzed Vegetable Protein (HVP), Hydrolyzed Animal Protein (HAP)

Protein is deeply hydrolyzed, with extremely high content of free amino acids and outstanding freshness, carrying a meat/soy-based aroma. It is the core freshness-enhancing ingredient for savory essences and compound sauces. Pure hydrolyzed protein lacks the complex aroma of fermentation and needs to be paired with brewed soy sauce to balance the flavor.

yeast extract

The self-dissolved product of microbial yeast is rich in glutamic acid and flavor peptides, with a mellow and fresh taste. It can mitigate the irritation of salt and acid, mask the fishy and mixed flavors of raw materials, and is suitable for low-salt and low-fat condiment formulas.

Disodium 5'-ribonucleotide (I+G) is a high-potency umami-enhancing additive that exhibits a significant umami synergistic effect with monosodium glutamate. A small amount of addition can significantly enhance umami intensity, without imparting an independent aroma, and only serves to intensify the umami sensation.

(III) Complete process of standardized sensory evaluation of soy sauce

Tasting environment: Constant temperature of 23~25℃, odor-free dedicated tasting room, natural light with white background, samples are randomly and blindly coded by numbers to eliminate interference from subjective preferences.

Four basic detection dimensions

Color: Dilute 2mL of the sample for observation. High-quality brewed soy sauce appears bright red-brown with a transparent luster; inferior samples are dark and black, turbid, and contain many suspended particles;

② Body and foam: Shake well and observe the foam. High-quality soy sauce produces a fine, dense, and long-lasting foam that adheres to the wall smoothly; inferior soy sauce produces coarse foam that dissipates quickly and has too thin a consistency;

③ Aroma (olfaction): Distinguish between soy sauce aroma, ester aroma, caramel aroma, ammonia odor, and rancid odor; high-salt liquid-state fermentation exhibits prominent ester aroma, while low-salt solid-state fermentation produces a rich soy sauce aroma; spoiled samples have a pungent ammonia and fermented sour odor;

④ Taste (mouthwash evaluation after dilution): Dilute with 0.5% warm water, and evaluate the freshness, balance between saltiness and sweetness, aftertaste, astringency, and fermentation off-flavor in order; high-quality samples exhibit a harmonious balance between freshness and saltiness, smoothness in the mouth, and a lingering aftertaste; defective samples taste bitter, sour, and astringent, with an abrupt saltiness.

Judgment basis: By combining the physicochemical indicators of amino acid nitrogen with the comprehensive sensory scores, it is evident that the freshness and aroma complexity of special-grade soy sauce are significantly superior to those of second- and third-grade products.

IV. Vinegar and sour seasonings: classification, flavor characteristics, and standardized tasting methods

Vinegar is a fermented acidic base seasoning. According to the national standard GB 2719-2018, vinegar is defined as an acidic condiment made from starch/sugar raw materials through microbial fermentation. Acidity intensity, fermentation aroma, and smoothness are the core distinguishing indicators.

(1) Mainstream classification and flavor characteristics of brewed vinegar

Gaoliang aged vinegar (Shanxi aged vinegar)

Made from sorghum and aged for a long time, it boasts a total acidity of ≥6g/100mL, a deep brown color, a rich and mellow sour taste, and a natural grainy caramelized aroma and sweetness. It lacks any sharp or irritating sensation and can withstand high-temperature stewing. It pairs well with braised dishes, marinated foods, and cold and dressed dipping sauces.

Glutinous rice vinegar (Zhenjiang vinegar)

Fermented and aged glutinous rice, with a total acidity of 4.5~5.5g/100mL, boasts a balanced sweetness and sourness, rich rice aroma, prominent freshness, and delicate sourness that doesn't irritate the throat. It is suitable for cold dishes, steaming, and compound seasoning sauces.

Rice vinegar

After short-term fermentation, the rice exhibits a total acidity of 4.0~4.5g/100mL, with a light yellow and transparent hue. It boasts a refreshing and singular sour taste, complemented by a delicate aroma of rice. This rice is ideal for making pickled vegetables and refreshing cold dishes.

Fruit vinegar (apple vinegar, grape vinegar)

Fruit and vegetable fermentation imparts a natural fruity aroma, with a mild acidity and a slightly high sweetness, making it suitable for seasoning beverages and light salads.

Alcoholic white vinegar

Edible alcohol is produced through liquid fermentation, and it is colorless and transparent, with only a single acetic acid stimulating taste and no complex aroma from fermentation. It is mostly used for pickling and cleaning to remove fishy smell, and is not suitable for direct dipping.

(II) Preparation of acidic seasoning products

Based on brewed vinegar, it is blended with glacial acetic acid, sweeteners, and spices, resulting in a lower production cost. However, its disadvantage is that the fermentation aroma is weak and the sour taste is sharp. Excessive consumption may lead to astringent sensation in the mouth. Strict adherence to GB 2760 is required to control the use of additives.

(III) Standardized Sensory Evaluation Operating Procedures for Edible Vinegar

Sample pretreatment: Conduct two parallel tests on the original vinegar and a 1% diluted solution with warm water to distinguish the differences in acidity sensation under light and heavy concentrations.

Four major sensory evaluation indicators

① Color: When observed through light, grain vinegar appears amber-red brown, rice vinegar is clear and light yellow, and fruit vinegar retains the natural color of the corresponding fruits and vegetables; there is no turbidity, white sediment, or mold spots;

② Aroma: Shake well and let it stand for a while before smelling. High-quality brewed vinegar possesses a persistent aroma of fermented grains/fruits, without any pungent industrial glacial acetic acid taste or alcohol rush. After rubbing the sample, the lingering aroma remains on the hand. The aroma of blended vinegar dissipates quickly;

③ Acid taste sensation: After dilution, when rinsing the mouth, the high-quality acetic acid sensation is gentle and lingering, with no sharp burning or astringent sensation upon swallowing; inferior acetic acid directly hits the throat, leaving a bitter and astringent aftertaste;

④ Aftertaste: High-quality brewed vinegar has a subtle sweet aftertaste and a rich aroma of grains; formulated vinegar only has a single sour taste, lacking a complex finish.

Simple auxiliary method for quality differentiation: Shake the sample vigorously. Pure brewed vinegar produces fine and dense foam that can be maintained for more than 1 minute; blended vinegar produces coarse and large foam that dissipates completely within 30 seconds.

summary

Salt, sugar/sweeteners, umami seasonings, and vinegar constitute the underlying framework of the four major flavors in condiments. The processing techniques of various raw materials directly determine the release intensity, layered perception, and aftertaste expression of saltiness, sweetness, umami, and sourness. R&D and quality control work cannot rely solely on single taste perception. It is necessary to identify the characteristics of raw materials in conjunction with the national standard classification system, and to establish a standardized blind sensory evaluation process to unify the judgment criteria and avoid common industry issues such as raw material selection errors, imbalanced formula flavors, and batch quality fluctuations.

In actual production, four types of basic seasonings work synergistically: salt amplifies the perception of fresh, sweet, and sour flavors; sugars mitigate the irritation of sour and salty flavors, enhancing overall roundness; umami substances add depth to the flavor; and vinegar balances the sweetness and heaviness. Only through the reasonable combination of these four elements can a seasoning product with balanced layers and stable palatability be created.