What “Unfiltered” Truly Means: The Pale Golden Hue of BORN Gold

KANPAI Makers’ Choices No.06

When a sake is described as “unfiltered,” it may sound as though it has bypassed filtration altogether. That reading does not fully reflect the brewing process. After fermentation, the mash, or moromi, is pressed to separate liquid sake from solid sake lees. This separation itself performs a filtering function.

What, then, does “unfiltered” mean in the case of BORN Gold?

Kato Kichibee Shoten’s official product information describes BORN Gold as a Junmai Daiginjo brewed with contract-grown Yamada Nishiki rice from a designated Special A growing area in Hyogo Prefecture and polished to a 50% rice-polishing ratio. This means that the weight of the polished white rice becomes 50% of the original brown rice weight. The producer also explains that the sake presents a pale golden hue because it is unfiltered.

Under the National Tax Agency’s labeling standards, the Junmai Daiginjo classification does not require a sake to be colorless. It refers to sake made only from rice, rice koji, and water, using rice polished to 50% or less and the ginjo brewing method, with especially good aroma, flavor, color, and luster. The presence of a pale hue and the Junmai Daiginjo classification are not contradictory.

The point is not simply that one step has been omitted. It is the decision of what to remove, what to retain, and at which stage.

The Mash Is First Separated into Sake and Sake Lees

Sake moromi is a fermenting mixture of steamed rice, rice koji, water, and other brewing components in which saccharification and fermentation are taking place. When fermentation is complete, rice-derived solids remain suspended in the liquid.

The process of pressing the mash and separating liquid from solid is known as joso. The liquid is collected as sake, while the solids remain as sake lees. The Japan Sake and Shochu Makers Association glossary likewise defines joso as the operation of pressing and filtering moromi into sake and sake lees.

Therefore, “unfiltered” on BORN Gold does not mean that the mash is bottled together with its lees. The producer points to a pale golden hue rather than white cloudiness. Being unfiltered and being a cloudy nigori sake are separate concepts.

Understanding “Unfiltered” Through Activated-Carbon Filtration

After pressing, sake may undergo additional processes to adjust its condition. One of these is filtration using activated carbon.

Activated carbon adsorbs color-related compounds and certain other components in sake. A publication by the National Research Institute of Brewing explains that activated carbon can adsorb coloring and off-flavor components, helping to limit discoloration and over-maturation. It also notes that carbon-filtered sake tends to have a lighter, cleaner profile than unfiltered sake.

Bacchus Global’s product information states that BORN Gold is bottled without activated-carbon filtration. Under that description, “unfiltered” does not mean that the mash is left unpressed. It refers to not adjusting the pressed sake with activated carbon.

Kato Kichibee Shoten’s official product page, however, uses the term “unfiltered” without identifying a specific filtration medium. What the producer directly associates with the term is the sake’s pale golden appearance. Public information alone does not establish a causal link between being unfiltered and any particular aroma or flavor.

Preserving the Golden Hue and Applying Heat Before Shipment

“Unfiltered” and namazake are not the same thing.

Namazake refers to sake that receives no heat treatment between pressing and shipment. Heat treatment, also known as hi-ire, is used to stabilize sake by controlling microorganisms and stopping enzymatic activity.

BORN Gold’s official description states that its unfiltered Junmai Daiginjo namazake is heat-treated immediately before shipment. Here, namazake refers to the sake before that final heat treatment. Because the finished product is heat-treated, it does not fall within the labeling category of namazake. Forgoing activated-carbon filtration and forgoing heat treatment are separate decisions.

This combination cannot be described simply as the omission of processing. The producer’s official information confirms heat treatment before shipment, while Bacchus Global’s product information separately describes the absence of activated-carbon filtration. What to retain and when to stabilize the sake are distinct decisions.

Blending Sake Matured at −10°C

Kato Kichibee Shoten’s official product information explains that sake matured at −10°C for up to one year is blended into BORN Gold. Ice-temperature maturation means storing sake below the freezing point of water while preventing the sake itself from freezing.

Here, blending does not necessarily mean adding an entirely different style of sake. In sake production, sake from multiple brewing lots or different storage units may be brought together to adjust the condition of the final product.

The number of lots used for BORN Gold and their respective proportions have not been made public. The official description also does not identify which sake is matured for a particular number of days or months. It would therefore be inaccurate to state that all of the sake is matured for a full year.

The confirmed elements are the blending of ice-temperature-matured sake and heat treatment immediately before shipment. Separately, Bacchus Global’s product information states that activated-carbon filtration is not performed.

No.06: The Choice Not to Erase Color

No.01 recorded a choice behind Shichiken HAKUSHIN: polishing rice to a 27% rice-polishing ratio and waiting for one year at −5°C. No.02 focused on HANEYA KIRABI, broadening the brewing season while narrowing the portion selected as nakagumi, the middle cut. No.03 examined Shirakane Shuzo’s SHIRAKANE-NO-TSUYU, assessing individual sweet potatoes and deciding which parts would not enter the secondary mash.

No.04 recorded Heiwa Shuzo’s choice to set separate polishing ratios for koji rice and kake rice in KID Junmai Ginjo Karakuchi Kid. No.05 documented Hamada Syuzou’s Sasshu Sekitoba Matcha, using matcha and green tea as fermentation ingredients and bringing together two spirit profiles after distillation.

For No.06, the choice recorded in BORN Gold is to retain the pale golden hue that the producer’s official information associates with being unfiltered.

That choice does not mean omitting every process after pressing. The mash is pressed. Ice-temperature-matured sake is blended. Heat treatment is applied before shipment. Separately, Bacchus Global’s product information states that the sake is not adjusted through activated-carbon filtration.

The word “unfiltered” alone does not reveal which process is absent and which processes remain. Read against the specific production stages, BORN Gold’s pale golden hue is associated with being unfiltered in the producer’s official information and emerges as the result of a deliberate choice about what to retain.

This article is intended solely to provide factual and cultural information about Kato Kichibee Shoten and BORN Gold, including its production design. It does not aim to promote or encourage the purchase or consumption of alcohol. It is intended for readers aged 20 and over.

บทความนี้จัดทำขึ้นเพื่อให้ข้อมูลเชิงข้อเท็จจริงและวัฒนธรรมเกี่ยวกับ Kato Kichibee Shoten และ BORN Gold รวมถึงแนวคิดด้านการผลิตเท่านั้น มิได้มีเจตนาเพื่อส่งเสริมการซื้อหรือการบริโภคเครื่องดื่มแอลกอฮอล์ บทความนี้จัดทำขึ้นสำหรับผู้อ่านอายุ 20 ปีขึ้นไป

Related Products

Product information: BORN Gold / Product information: BORN Junmai-Daiginjo Non-filter Nama-Genshu

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