1. Definition of Single Strength Reference Brix
Single strength reference Brix refers to the soluble solids reference value of a concentrated juice when it is reconstituted with water back to its original straight juice state. In practice, this value is used to calculate the straight juice equivalent (SJE) of concentrated juice, and the result is linked to fruit content declaration, %juice labeling, ingredient order, and product category classification. Codex stipulates that the final soluble solids of reconstituted juice must satisfy the minimum Brix specified in its Annex, and the U.S. FDA uses the single-strength minimum Brix when calculating the %juice of beverages containing concentrated juice.
Figure 1. Single Strength Concept Diagram
An important point is that the Brix of the final product and the fruit content are not the same concept. For example, even if the final product is 12 °Bx, if that Brix is contributed by sugar, sweeteners, pulp solids, or other fruit juices, the fruit content must be calculated separately. Therefore, it is advisable to manage final Brix and fruit content as distinct parameters in the formulation sheet.
2. Regulatory Framework by Country and Regulatory Purpose
Korea: The MFDS amendment explanatory materials clearly state that the single strength reference Brix of 100% pressed juice is the standard for classifying fruit and vegetable juice product categories. Values publicly confirmed in the Food Code Commentary include: grape/western pear 11, apple/lime 10, mandarin/grapefruit/papaya 9, pear/guava 8, peach/apricot/strawberry/lemon 7, plum/melon/Japanese apricot 6.
Japan: JAS 1075:2023 provides detailed Brix and acidity standards for reconstituted juice by fruit type. For example: apple 10, grape 11, orange 11, pineapple 11, mango 13 °Bx; lemon 4.5%, lime 6.0%, and ume (Japanese apricot) 3.5% are managed by acidity standards.
Codex: As the international trade standard, Codex establishes minimum Brix values for reconstituted juice in its Annex, and stipulates that fruits not listed in the table shall use the Brix of the original juice from which the concentrate was made. Representative values include apple 11.5, grape 16.0, pineapple 12.8, and mango 13.5. Notes on country-specific legal application or acidity correction are attached for orange, lemon, and lime.
U.S. FDA: 21 CFR 101.30 provides a single-strength minimum Brix table for calculating the labeled percentage of juice in beverages containing concentrated juice. Additionally, 21 CFR 101.4(c) stipulates that water added in excess of that required for reconstitution must be separately declared as “water” in the ingredient list. In other words, the U.S. links the single strength concept to both fruit content calculation and ingredient labeling.
EU: Manages minimum Brix for reconstituted juice under Directive 2001/112/EC Annex V, maintaining the production, composition, and labeling framework for juice products in its 2024 revision. In this document, the EU is summarized from a practical standpoint as an internationally harmonized framework similar to Codex rather than providing a separate detailed table.
| Region | Primary Reference | Practical Implication | Notes |
| Korea | MFDS amendment + public commentary | Product category classification; domestic reference Brix interpretation | Public tables cover selected fruit types |
| Japan | JAS 1075:2023 | Highly detailed reconstituted Brix/acidity standards by fruit type | Lemon, lime, ume managed by acidity |
| Codex | CXS 247-2005 | International trade minimum Brix standard | Unlisted fruits use original juice Brix |
| U.S. | 21 CFR 101.30 / 101.4 | %Juice labeling calculation; excess water declaration | Directly linked to labeling and formulation calculation |
Table 1. Practical Differences in Country-Specific Regulatory Frameworks
Figure 2. Reference Value Comparison for Major Fruit Types (Korea Public Table · Japan JAS · Codex · U.S. FDA)
3. Principles of Fruit Content Calculation for Concentrated Juice
Calculating fruit content from concentrated juice is fundamentally a soluble solids balance problem. By comparing the actual Brix of the concentrate with the reference Brix set by the target market country, one can calculate how many kilograms of straight juice the concentrate corresponds to. By setting this value as the Straight Juice Equivalent (SJE), blended juices, partial juice beverages, and 100% reconstituted juices can all be designed using the same logic.
Figure 3. Fruit Content Calculation Formulas and Reverse Calculation
| Practical Calculation Formulas |
| SJE (kg) = Amount of concentrate used (kg) × [Actual °Bx of concentrate ÷ Reference Brix (°Bx)] Fruit content (%) = ΣSJE ÷ Total batch weight × 100 Concentrate required from target fruit content (kg) = Target fruit content (%) × Total batch × Reference Brix ÷ Actual °Bx ÷ 100 For acidity-based fruits (e.g., lemon, lime, ume): apply titratable acidity (anhydrous citric acid basis) in place of °Bx in the same manner. |
In blended juices, since reference values differ by fruit, SJE must be calculated separately per fruit and then summed. For example, when using both orange and grape juice together, if the two juices are grouped and calculated using a single average Brix, the declared fruit content may deviate from the actual designed amount. Both the Japan JAS and Codex frameworks are safest understood as premising this per-fruit conversion approach.
4. Product Design Examples
Example 1) Designing 30% apple fruit content in a 1,000 kg product
If apple concentrate is 70 °Bx and the target fruit content is 30%, the required straight apple equivalent is 300 kg. Applying the Korea/Japan reference Brix of 10 °Bx, the required concentrate amount is 42.9 kg. Using the Codex/U.S. apple reference of 11.5 °Bx, 49.3 kg is required. In other words, the required concentrate amount and cost differ depending on the reference standard applied, even for the same ‘apple 30%’ product.
| Reference Applied | Apple Ref. Brix | SJE Required | 70 °Bx Conc. Required |
| Korea (Public Table) | 10 | 300 kg | 42.9 kg |
| Japan JAS | 10 | 300 kg | 42.9 kg |
| Codex / U.S. FDA | 11.5 | 300 kg | 49.3 kg |
Table 2. Required Concentrate Amounts by Country Standard for a 30% Apple Beverage
Example 2) Designing a blended juice with orange 15% + grape 10%
Assuming orange concentrate 65 °Bx and grape concentrate 68 °Bx are used to design a final 1,000 kg product. Under Japan JAS standards (orange 11, grape 11 °Bx), 25.4 kg of orange concentrate and 16.2 kg of grape concentrate are required. The total actual weight of concentrate in the final product is 41.6 kg, but the declared fruit content is 25%. In other words, the actual amount of concentrate added and the fruit content must be viewed as distinct parameters.
| Juice | Target Fruit Content | Reference Brix | Conc. Spec. | Conc. Required |
| Orange | 15% | 11 °Bx | 65 °Bx | 25.4 kg |
| Grape | 10% | 11 °Bx | 68 °Bx | 16.2 kg |
| Total | 25% | — | — | 41.6 kg |
Table 3. Blended Juice Design Example Based on Japan JAS Standards
Example 3) Handling acidity-based fruits such as lemon and lime
For lemon and lime, some Brix values exist in certain standards, but Japan JAS and the U.S. FDA treat acidity standards as the primary or co-primary criterion. For these fruit types, formulating solely on the basis of actual Brix of the concentrate may lead to errors in labeling and specification interpretation. It is therefore safer to manage the titratable acidity standard in a separate column.
5. Design Method for Products Using Concentrated Juice
Figure 4. Concentrated Juice Product Design Flow
| Design Stage | Key Question | Calculation Basis | Practical Point |
| Target Market Setting | Which country’s regulations govern sales? | Country-specific reference table | Declared fruit content may differ even with the same formulation |
| Product Type Decision | 100% reconstituted juice or xx% juice drink? | Food category / labeling framework | Fix product type before beginning design |
| Confirm Conc. Specs | What are the actual °Bx, acidity, and aroma recovery? | Raw material COA | Manage discrepancy between spec sheet and actual measured values |
| Fruit Content Calculation | Does it meet the target fruit content? | SJE calculation | For blended juices: convert per fruit, then sum |
Table 4. Key Checkpoints at Each Product Design Stage
In practice, the most stable approach is to separate the fruit content calculation table from the final Brix/cost simulation table. First, calculate the straight equivalent by country-specific standards to confirm the declarable fruit content, then in the next stage, use sugar, sweeteners, acids, flavors, pulp, and thickeners to achieve the target sensory and cost targets. In markets like the U.S., where water added beyond the reconstitution amount is separately listed in the ingredient statement, this distinction becomes even more critical.
Appendix A. Korea Publicly Confirmed Reference Table
The table below represents Korean reference Brix values within the publicly confirmed commentary scope. The MFDS amendment materials explain that these values serve as the standard for food category classification, and the public commentary table presents values grouped for certain fruit types.
| Korea Public Commentary Scope | Reference Brix |
| Grape, Western Pear | 11 °Bx or above |
| Apple, Lime | 10 °Bx or above |
| Mandarin, Grapefruit, Papaya | 9 °Bx or above |
| Pear, Guava | 8 °Bx or above |
| Peach, Apricot, Strawberry, Lemon | 7 °Bx or above |
| Plum, Melon, Japanese Apricot (Ume) | 6 °Bx or above |
Table A-1. Korea Publicly Confirmed Reference Brix Values
Note: Korean data has been directly confirmed for only selected fruit types within the publicly available scope. For final export/labeling decisions for the Korean market, always use the most current original standards as of the time of application.
Appendix B. Japan JAS 1075:2023 Detailed Table
| Fruit | Reconstituted Juice Brix (°Bx) | Fruit | Reconstituted Juice Brix (°Bx) |
| Orange | 11 | Western Pear | 11 |
| Satsuma Mandarin | 9 | Persimmon | 14 |
| Grapefruit | 9 | Quince | 10 |
| Apple | 10 | Plum | 6 |
| Grape | 11 | Apricot | 7 |
| Pineapple | 11 | Cranberry | 7 |
| Peach | 8 | Banana | 23 |
| Natsumikan | 9 | Papaya | 9 |
| Hassaku | 10 | Kiwi | 10 |
| Iyokan | 10 | Mango | 13 |
| Ponkan | 11 | Guava | 8 |
| Shikuwasa | 8 | Passion Fruit | 14 |
Table B-1. Japan JAS Reconstituted Juice Brix Standards (A.3)
| Acidity-Based Fruit Types | Acidity Standard (%) |
| Lemon | 4.5 |
| Lime | 6.0 |
| Ume (Japanese Apricot) | 3.5 |
Table B-2. Japan JAS Reconstituted Juice Acidity Standards (A.4)
Appendix C. Codex and U.S. FDA Representative Values
| Fruit | Japan JAS | Codex | U.S. FDA | Notes |
| Apple | 10 | 11.5 | 11.5 | Codex acknowledges natural variation by country in footnote |
| Grape | 11 | 16.0 | 16.0 | Codex grape = international trade reference value |
| Orange | 11 | 11.8–11.2 | 11.8 | Codex includes note on importing country laws and acidity correction |
| Grapefruit | 9 | 10.0 | 10.0 | U.S. has footnote on citric acid correction |
| Pineapple | 11 | 12.8 | 12.8 | Codex notes below 10 °Bx not permitted |
| Mango | 13 | 13.5 | 13.0 | Notable country-to-country variation |
| Guava | 8 | 8.5 | 7.7 | Note formulation quantity differences by market |
| Strawberry | — | 7.5 | 8.0 | Not directly listed in JAS table |
| Tomato | — | 5.0 | 5.0 | Vegetable-based, but frequently compared in labeling practice |
Table C-1. International Comparison Table for Major Fruit Types