Frozen baked sweet potatoes are easy to enjoy because you only need to warm them in the microwave, but you need to check the product page for differences between weight options and for whether the product works as a gift. In this article, we have organized the publicly available product information and reviews for Zaiho’s frozen baked sweet potatoes (Beniharuka) from the Zaiho Official Online Store Rakuten Ichiba shop (財宝公式通販 楽天市場店) into five points: contents, shelf life, ingredient labeling, suitability as a gift, and reviews. Please note that 蜜焼き芋 (mitsu yakiimo) in the product name is the shop’s own name for the product; it does not indicate the amount of syrup, the level of sweetness, or superior quality.
*The Amazon link goes to the same store’s item in different specifications (Amazon: 1.5kg (3 bags of 500g) only, while Rakuten Ichiba lets you choose 500g / 1kg / gift 1kg / 1.5kg / 3kg). The amount and contents in this article are based on the Rakuten Ichiba item. Please check the details on the Amazon product page before purchasing.
What We Confirmed
- Contents and serving size guide
- Storage method and shelf life
- Ingredients and allergen labeling
- Suitable as a gift?
- Trends in publicly available reviews
Basic Information
This table transcribes what is stated on the product page. However, the “not confirmed” labels and any notes we add are our own.
| Product Name | さつまいも 焼き芋 冷凍 紅はるか 500g/1kg/1.5kg/3kg 贈答用 蜜焼き芋 鹿児島産 やきいも 冷やし焼き芋 お菓子 おやつ 代用 食品 お祝い (Sweet potato, baked sweet potato, frozen, Beniharuka, 500g/1kg/1.5kg/3kg, for gifts, mitsu yakiimo, Kagoshima-grown, baked sweet potato, chilled baked sweet potato, sweets, snack, substitute, food, celebration)Source: The product name shown on the Rakuten Ichiba product page, minus the shop’s promotional and use-case terms (accessed September 30, 2026) |
|---|---|
| Name | Frozen baked sweet potatoes (冷凍焼き芋)Source: Rakuten Ichiba product page description (accessed September 30, 2026) |
| Contents | 500g x 1 bag / 1kg (2 bags of 500g) / gift 1kg (贈答用1kg; 2 bags of 500g) / 1.5kg (3 bags of 500g) / 3kg (6 bags of 500g). Amounts are given by weight (g); we found no listing of how many potatoes come in a bag or how large each one isSource: Rakuten Ichiba product page description (accessed September 30, 2026) |
| What Changes by Selection | Weight (500g / 1kg / gift 1kg / 1.5kg / 3kg). Only when gift 1kg is chosen is the item described as arriving in simple wrapping. A message card and noshi (gift wrapping label) are options, and the listing states they cannot be combinedSource: Rakuten Ichiba product page description (accessed September 30, 2026) |
| Storage Method | Frozen (−18°C or below)Source: Rakuten Ichiba product page description (accessed September 30, 2026) |
| Best-Before Date | One year from the manufacturing date when stored frozen. The listing advises eating it promptly after thawing. We found no number of days listed for after thawing or after openingSource: Rakuten Ichiba product page description (accessed September 30, 2026) |
| Country of Origin | Sweet potato (Beniharuka grown in Kagoshima Prefecture)Source: ingredients field of the Rakuten Ichiba product page (accessed September 30, 2026) |
| Place of Processing | Not confirmed (the manufacturer’s address is given in the row below, but no listing of it as the place of processing was found) |
| State / How to Eat (Whether Heating Is Required) | The listing describes it as baked and then flash-frozen. It says to place it on a plate lined with kitchen paper while still frozen, heat it in a microwave without covering it with plastic wrap, and always open the bag before heating. No heating time (in seconds) was found, so this is not confirmed. Eating it thawed naturally and chilled is also described. Because the ingredient is an agricultural product, the listing states that color, texture, and shape vary from piece to pieceSource: Rakuten Ichiba product page description images (accessed September 30, 2026) |
| Thawing Method | Letting it thaw naturally or warming it in a microwave is described as ways to eat it. The steps for natural thawing (refrigerator or room temperature, etc.) and the number of days it keeps after thawing were not listed, so these are not confirmedSource: Rakuten Ichiba product page description images (accessed September 30, 2026) |
| Shipping | The listing states that the shop chooses the carrier, depending on the product and the delivery address, from Sagawa Express, Yamato Transport, Japan Post (Yu-Pack), and mail delivery (Yu-Packet). You cannot specify the carrier, and if no delivery date is specified, it is delivered as soon as possibleSource: delivery information on the Rakuten Ichiba product page (accessed September 30, 2026) |
| Manufacturer | Zaiho Co., Ltd. (株式会社財宝; 鹿児島県鹿屋市新栄町35-7)Source: Rakuten Ichiba product page description (accessed September 30, 2026) |
| Shop | Zaiho Official Online Store Rakuten Ichiba shop (財宝公式通販 楽天市場店) (Rakuten Ichiba). We could not confirm the seller’s address, so this is not confirmed |
Prices are not listed here because they change. Please check the current price and stock availability at the link above.
Ingredients and Allergen Labeling
Within what we could check, the product description on the Rakuten Ichiba product page lists sweet potato (Beniharuka grown in Kagoshima Prefecture) as the ingredient. However, we found no allergen (specified ingredients) labeling field in either the product description or the product description images. The Amazon 1.5kg product page also had no allergen field or ingredients field; instead, its product features state 100% Beniharuka grown in Kagoshima Prefecture.
Because there is no allergen labeling field, we cannot say either that the product contains allergens or that it does not. This item is not confirmed. If you have a food allergy, please ask the shop before buying, or check the food information label on the product when it arrives.
Reference: Consumer Affairs Agency, Japan, “About Allergen Labeling” (accessed September 30, 2026)
Five Things to Check Before Buying
| What to Check | For This Product | Basis |
|---|---|---|
| 1. Contents / serving size | Choose from 5 options: 500g / 1kg / gift 1kg / 1.5kg / 3kg. No serving size guide is listed, so this is not confirmed | Rakuten Ichiba product page description |
| 2. Storage method and shelf life | Frozen (−18°C or below). Best-before date is one year from the manufacturing date when stored frozen. The number of days after thawing or opening is not listed, so this is not confirmed | Rakuten Ichiba product page description |
| 3. Ingredients and allergen labeling | The ingredient is sweet potato (Beniharuka grown in Kagoshima Prefecture). No allergen labeling field was found, so this is not confirmed | Rakuten Ichiba product page (description and description images) |
| 4. Suitable as a gift? | Options for noshi and a message card are available, and the listing states they cannot be combined. Simple wrapping is for gift 1kg only. The product page is inconsistent about noshi (details in the gift section) | Rakuten Ichiba product page description |
| 5. Review trends | The Rakuten rating is 4.61 / 5 (1,241 reviews). We read the first 60 reviews in the standard sort order (Rakuten’s default) (posted November 2025 to September 2026; latest September 28, 2026) and all 45 reviews rated 1★ and 2★ (posted May 2020 to September 2026), 105 in total. These trends may not reflect the product’s current condition. Many reviewers praise the sweetness and convenience, while some point to hit-or-miss quality and variation in size | Rakuten customer reviews (“Minna no Review”) (accessed September 30, 2026) |
Suitable as a Gift?
As for noshi, the product description says that if you want one, you should choose it from the item options. However, the inscription types are said to be listed at a separate link within the product description, which we could not confirm for this article. In addition, the settings data embedded in the product page marks noshi as not supported, which conflicts with the product description. We use the product description as our source here, but please confirm on the order screen whether you can actually select it.
- Message card: A design with a fixed message is among the options; the listing states the wording is fixed and cannot be specified. It also states it cannot be combined with noshi (Source: Rakuten Ichiba product page description, accessed September 30, 2026)
- Wrapping: The product description says only when gift 1kg is chosen does the item arrive in simple wrapping, and other sizes cannot be wrapped. On the other hand, the product description images carry a note to the effect that it is delivered in a gift box for presents, which differs from the wording of the product description. We could not confirm which applies to which size (Source: Rakuten Ichiba product page description and description images, accessed September 30, 2026)
- Statement of account: The listing states that a statement showing the amount, etc., is not enclosed (Source: same as above)
- Occasions: The product description lists uses such as seasonal gifts and return gifts (uchi-iwai), but notes that some products cannot meet the desired use because of the best-before date (Source: same as above)
- Name printing: We could not confirm this
Because it is stored frozen, also consider whether the recipient has freezer space. Of the 105 reviews we read, six posts among the first 60 in the standard sort order said they used it as a gift and it was well received by the recipient. This is a trend within what we read and may not reflect the product’s current condition (Source: Rakuten customer reviews, accessed September 30, 2026).
What Public Reviews Say
Below we have organized the Rakuten Ichiba product reviews by theme. The rating figures are as of the time viewed and may change afterward.
| Site | Rating | Reviews | Date Viewed |
|---|---|---|---|
| Rakuten customer reviews (product page) | 4.61 / 5 | 1,241 reviews | September 30, 2026 |
Rating breakdown: 5★ 925 / 4★ 212 / 3★ 59 / 2★ 27 / 1★ 18 (as shown on Rakuten Ichiba, viewed September 30, 2026)
What we read: the first 60 reviews in Rakuten’s default (standard) sort order (posted November 2025 to September 2026; latest September 28, 2026), plus all 18 reviews filtered to 1★ (posted May 2020 to December 2025) and all 27 filtered to 2★ (posted July 2020 to September 2026), 105 in total. We did not read the 3★ reviews. These are trends within what we read and may not reflect the product’s current condition.
What Reviewers Praise
Sweetness and plenty of syrup
Of the 60 reviews in the standard sort order, 31 mentioned sweetness or the amount of syrup. Most said there was plenty of syrup or that it was as sweet as expected; all 60 were posted within the last two years.
Easy in the microwave; eat just the amount you want
19 of the 60 posts mentioned how easy it is to eat by just warming it in the microwave, or being able to take out only the amount you want to eat from the bag.
Sticky, moist texture
14 of the 60 posts wrote that it was sticky and moist, soft, and easy to eat.
Satisfaction as a gift
6 of the 60 posts said they used it as a gift and it was well received by the recipient. The weights included 1kg, 1.5kg, 3kg, and gift 1kg.
Source: Rakuten customer reviews (accessed September 30, 2026)
What Reviewers Note
No sweetness or syrup noticed; dry texture
19 of the 45 reviews rated 1★ and 2★ and one of the 60 in the standard sort order, 20 in total (10 of them posted within the last two years), mentioned not noticing sweetness or syrup, or feeling that it was dry. Many posts from 2021 to 2023 say the same.
Hit-or-miss quality and variation between pieces
12 of the 45 reviews rated 1★ and 2★ and two of the 60 in the standard sort order (14 in total, 6 of them posted within the last two years) mentioned that taste and texture differed depending on the delivery even though it was the same product. As for what the variation consisted of, 17 posts among the 1★ and 2★ reviews said it had many stringy fibers (2 of them within the last two years; most were posted between 2020 and 2023), and 8 posts (3 within the last two years) mentioned discoloration or spoilage, such as the inside being green or black, or tasting bitter.
How to check: The shop’s note that color, texture, and shape vary because the ingredient is an agricultural product is included in the “State / How to Eat” row of “Basic Information” in this article.
Variation in potato size and number
7 of the 45 reviews rated 1★ and 2★ and one of the 60 in the standard sort order (8 in total, 3 of them posted within the last two years) said that the size and number of potatoes differed within a bag or between bags, and that they felt small or thin. This includes a post that used the 3kg as a gift and found the potatoes small.
How to check: The fact that the contents are given as a number of 500g bags, with no listing of the number of potatoes or the size of each one, is written in the “Contents” row of “Basic Information” in this article.
Source: Rakuten customer reviews (accessed September 30, 2026)
Who It Suits / Who Should Be Careful
Who It Suits
- You want to keep baked sweet potatoes stocked in the freezer and warm up only what you want to eat
- You want to choose a weight from 500g to 3kg
- You want the option of eating them thawed naturally and chilled, or warmed in the microwave
- You want to give them as a gift using the options for noshi, a message card, or simple wrapping (gift 1kg)
Who Should Be Careful
- You want to check allergen labeling before buying (no labeling field found; not confirmed)
- You want consistent potato size, sweetness, and texture (reviews point to variation between pieces)
- You want to know the heating time and the number of days it keeps after thawing beforehand (not listed; not confirmed)
- You want to wrap and give sizes other than gift 1kg (the listing states other sizes cannot be wrapped)
Prices, stock, shipping fees, and delivery dates are subject to change. This article’s information-as-of date is September 30, 2026. Please be sure to check the listing at the link before purchasing.
This article contains affiliate links (advertising). Editorial Policy
*The Amazon link goes to the same store’s item in different specifications (Amazon: 1.5kg (3 bags of 500g) only, while Rakuten Ichiba lets you choose 500g / 1kg / gift 1kg / 1.5kg / 3kg). The amount and contents in this article are based on the Rakuten Ichiba item. Please check the details on the Amazon product page before purchasing.
Summary
- The weight comes in 5 options from 500g to 3kg, and changes with the number of 500g bags. Only gift 1kg is described as arriving in simple wrapping
- Storage is frozen (−18°C or below), and the best-before date is one year from the manufacturing date when stored frozen. The number of days after thawing or opening and the heating time are not confirmed
- No allergen labeling field was found, so this is not confirmed. Many reviewers praise the sweetness and convenience, while some point to hit-or-miss quality and variation in size (within the 105 reviews we read; this may not reflect the product’s current condition)
Related Pages
This article organizes information publicly available on retail and review sites. Product details such as contents, storage method, and ingredients may change. Please check the seller’s listing for the latest information.
Comments on taste or quality are summarized from third-party posts cited with their source, and are not Ochinity’s own evaluation. Our approach to writing articles is described in our Editorial Policy.
Information as of: September 30, 2026 / Sources: Rakuten Ichiba “財宝公式通販 楽天市場店” product page, Amazon product page (1.5kg), Rakuten customer reviews (“Minna no Review”), Consumer Affairs Agency, Japan, “About Allergen Labeling”
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