SUPPLEMENTAL INDENTURE

EXHIBIT 4.1

SUPPLEMENTAL INDENTURE

SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of April 16, 2007, among Super Rx, Inc., a California corporation (the “Guaranteeing Subsidiary”), a subsidiary of Stater Bros. Holdings Inc. (or its permitted successor), a Delaware corporation (the “Company”), the Company, the other Guarantors (as defined in the Indenture referred to herein) and The Bank of New York Trust Company, N.A., as successor trustee under the indenture referred to below (the “Trustee”).

W I T N E S S E T H

WHEREAS, the Company has heretofore executed and delivered to the Trustee an indenture (the “Indenture”), dated as of June 17, 2004, providing for the issuance of 8.125% Senior Notes due 2012 and Floating Rate Notes due 2010 (the “Notes”);

WHEREAS, the Company, the Guaranteeing Subsidiary and the other Guarantors desire to amend the Indenture to provide for an unconditional guarantee by the Guaranteeing Subsidiary of all of the Company’s Obligations under the Notes and the Indenture (the “Subsidiary Guarantee”);

WHEREAS, the additional Subsidiary Guarantee provides additional rights and benefits to the Holders of the Notes under Section 10.01(d) of the Indenture; and

WHEREAS, pursuant to Sections 9.06 and 10.01 of the Indenture, the Trustee is authorized to execute and deliver this Supplemental Indenture.

NOW THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the equal and ratable benefit of the Holders of the Notes as follows:

1. CAPITALIZED TERMS. Capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture.

2. AMENDMENTS.

(a) The preface on page 1 of the Indenture is hereby amended and restated in its entirety to read as follows:

“INDENTURE dated as of June 17, 2004 among Stater Bros. Holdings Inc., a Delaware corporation (“Stater Bros.”), Stater Bros. Markets (“Markets”), Stater Bros. Development, Inc. (“Development”), Santee Dairies, Inc. (“Santee”), and Super Rx, Inc. (“Super Rx” collectively with Markets, Development and Santee, the “Guarantors”) and The Bank of New York Trust Company, N.A. (as successor to The Bank of New York), as trustee (the “Trustee”).”

(b) The definition of “Guarantors” set forth in Section 1.01 of the Indenture is hereby amended and restated in its entirety to read as follows: ““Guarantors” means Markets, Development, Santee, Super Rx and each other Person that is required to become a Guarantor by the terms hereof after the Issue Date, in each case until such Person is released from its Guarantee pursuant to the terms hereof.”

(c) A new definition of “Super Rx” is hereby inserted in Section 1.01 of the Indenture alphabetically as follows: ““Super Rx” means Super Rx, Inc., a California corporation.”

(d) The ultimate proviso contained in Section 4.19 of the Indenture is hereby amended and restated in its entirety to read as follows: “; (ii) has Total Assets of less than $10.0 million and Stater Bros. has provided the Trustee with written notice requesting such release and an Officers’ Certificate certifying the amount of such Total Assets; provided, further, that Super Rx shall not be entitled to a release pursuant to the provisions of this clause (ii).”

(e) Section 9.02(b)(iv) of the Indenture is hereby amended and restated in its entirety to read as follows: “such Guarantor, other than Markets, Development, Santee, and Super Rx, having Total Assets of less than $ 10.0 million and Stater Bros. providing written notice to the Trustee requesting such release and an Officers’ Certificate certifying the amount of such Total Assets pursuant to, Section 4.19;”

3. AGREEMENT TO GUARANTEE. The Guaranteeing Subsidiary hereby agrees as follows:

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4. EXECUTION AND DELIVERY. Each Guaranteeing Subsidiary agrees that the Subsidiary Guarantees shall remain in full force and effect notwithstanding any failure to endorse on each Note a notation of such Subsidiary Guarantee.

5. GUARANTEEING SUBSIDIARY MAY CONSOLIDATE, ETC. ON CERTAIN TERMS.

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6. RELEASES.

7. NO RECOURSE AGAINST OTHERS. No past, present or future director, officer, employee, incorporator, stockholder or agent of the Guaranteeing Subsidiary, as such, shall have any liability for any obligations of the Company or any Guaranteeing Subsidiary under the Notes, any Subsidiary Guarantees, the Indenture or this Supplemental Indenture or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder of the Notes by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for issuance of the Notes.

8. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL

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INDENTURE BUT WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

9. COUNTERPARTS. The parties may sign any number of copies of this Supplemental Indenture. Each signed copy shall be an original, but all of them together represent the same agreement.

10. EFFECT OF HEADINGS. The Section headings herein are for convenience only and shall not affect the construction hereof.

11. THE TRUSTEE. The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the Guaranteeing Subsidiary and the Company.

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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed, all as of the date first above written.

Dated: April 16, 2007