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                                                                  EXHIBIT 4.15.1

                                AMENDMENT NO. 1
                                       TO
                           REVOLVING CREDIT AGREEMENT
                                        

     THIS AMENDMENT NO. 1 TO REVOLVING CREDIT AGREEMENT dated as of May 1, 1998
(the "Amendment"), is entered into by and among CERTIFIED GROCERS OF CALIFORNIA,
LTD., a California corporation operating primarily on a cooperative basis (the
"Borrower"), the Lenders (as defined below), and COOPERATIEVE CENTRALE
RAIFFEISEN-BOERENLEENBANK B.A., "RABOBANK NEDERLAND", NEW YORK BRANCH
("Rabobank") as a Lender (as defined below) and as the Agent (as defined below).

                                    RECITALS

     A.  The Borrower has entered into that Revolving Credit Agreement dated as
of April 10, 1998 (the "Credit Agreement"), among the Borrower, the Lenders
party thereto (which term shall include the Issuing Bank) (and their successors
and assigns) (collectively, the "Lenders") and Rabobank, not in its individual
capacity but solely in its capacity as the Agent (the "Agent").

     B.  The Lenders have extended credit to the Borrower for the purposes
permitted in the Credit Agreement.

     C.  Each Guarantor is indebted to the Lenders pursuant to and on the terms
set forth in, among other things, those unconditional Guaranties executed by
each Guarantor in respect of the Obligations.

     D.  Notwithstanding efforts to do so, the Borrower has been unable to
arrange for the release and termination of an Irrevocable Transferable Letter of
Credit No. 51794658 in the face amount of $1,500,000 for the benefit of TriNet
Essential Facilities XII, Inc. issued by BT Commercial Corporation. The Borrower
has requested that the Agent and the Lenders amend the Credit Agreement to
permit, among other things, the Indebtedness evidenced by such letter of credit
and the Lien securing the obligations thereunder.

     E.  The Agent and the Lenders have agreed to so amend the Credit Agreement,
but only to the extent, in accordance with the terms and subject to the
conditions and in reliance upon the representations and warranties set forth
below.

                                   AGREEMENT

     NOW, THEREFORE, in consideration of the foregoing recitals and other good
and valuable consideration, the receipt and adequacy of which is hereby
acknowledged, and intending to be legally bound, the parties hereto agree as
follows:

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      1.  DEFINITIONS.  Capitalized terms used but not defined in this Amendment
shall have the meanings given to them in the Credit Agreement.

      2.  AMENDMENTS TO CREDIT AGREEMENT.

          2.1  SECTION 1.1 (DEFINITIONS).  A definition of the term "Requisite
Lenders" is deleted in its entirety and is replaced with the following:

               "Requisite Lenders" means any combination of Lenders whose
          combined Pro Rata Share (and voting interest with respect thereto) of
          all amounts outstanding under this Agreement, or, in the event there
          are no amounts outstanding, the Aggregate Commitments, is greater than
          sixty-six and two-thirds percent (66-2/3%) of all such amounts
          outstanding or the Aggregate Commitments, as the case may be.

          2.2  SECTION 1.1 (DEFINITIONS).  A definition of the term "TriNet
Letter of Credit" is added to read as follows:

               "TriNet Letter of Credit" means the Irrevocable Transferable
          Letter of Credit No. 51794658 in the face amount of $1,500,000 issued
          for the benefit of TriNet Essential Facilities XII, Inc. by BT
          Commercial Corporation under the Existing Debt more fully described in
          SCHEDULE 7.3.

          2.3  SECTION 2.1.1(d) (OVERADVANCES). SECTION 2.1.1(d) of the Credit
Agreement is deleted in its entirety and is replaced with the following:

               (d) OVERADVANCES.  If at any time and for any reason (i) the
          aggregate principal amount of the Revolving Loans then outstanding,
          plus the Letter of Credit Undrawn Amount shall exceed the Aggregate
          Commitments or (ii) the Letter of Credit Undrawn Amount shall exceed
          the Letter of Credit Commitment (the amount of such excess, if any, in
          each case being an "Overadvance"), the Borrower shall immediately
          repay the full amount of such Overadvance, together with all interest
          accrued thereon; provided, that in the case of an Overadvance relating
          to the Letter of Credit Commitment, such amount shall be held as cash
          collateral for undrawn Letters of Credit, and shall immediately be
          returned to the Borrower if Letters of Credit in an amount sufficient
          to eliminate such Overadvance expire undrawn.

          2.4  SECTION 2.1.1(g) (LETTER OF CREDIT SUBLIMIT UNDER REVOLVING
CREDIT FACILITY).  Section 2.1.1(g) of the Credit Agreement is deleted in its
entirety and is replaced with the following:

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               (g) LETTER OF CREDIT SUBLIMIT UNDER REVOLVING CREDIT FACILITY.
          Without limiting the generality of the foregoing, each Lender
          severally agrees that a Responsible Person of the Borrower may, by
          delivery of notice to the Agent in accordance with SECTION 2.5, also
          request the Issuing Bank to issue one or more standby or documentary
          letters of credit under the Letter of Credit Commitment for the
          account of the Borrower, which letters of credit shall be in the
          standard form of the Issuing Bank (each a "Letter of Credit"); in
          which event, after satisfaction by the Borrower of all conditions
          precedent set forth in SECTION 4.2, the Issuing Bank shall issue such
          Letters of Credit subject to and in accordance with SECTION 2.1.2;
          provided, however, nothing contained in this Agreement shall under any
          circumstance be deemed to require the Issuing Bank to issue any Letter
          of Credit which, taking into account the issuance of such Letter of
          Credit, would either (i) cause the Letter of Credit Undrawn Amount to
          exceed the Letter of Credit Commitment or (ii) cause the aggregate
          principal amount of the Revolving Loans then outstanding, plus the
          Letter of Credit Undrawn Amount to exceed the Aggregate Commitments.

          2.5  SECTION 4.1(m) (TERMINATION OF EXISTING DEBT).  SECTION 4.1(m) of
the Credit Agreement is deleted in its entirety and is replaced with the
following:

               (m) TERMINATION OF EXISTING DEBT. The Agent shall have received
          written evidence satisfactory to the Lenders in their sole discretion
          that the Borrower's existing Indebtedness disclosed on SCHEDULE 7.3
          (other than Patronage Dividend Certificates and the TriNet Letter of
          Credit) (the "Existing Debt") has been, or shall with the proceeds of
          the first Loan be, terminated and paid in full, and all Liens securing
          such Existing Debt have been, or upon the making of the first Loan
          shall be, terminated or released.

          2.6  SECTION 7.1(a) (LIENS; NEGATIVE PLEDGES).  SECTION 7.1(a) of the
Credit Agreement is deleted in its entirety and is replaced with the following:

               (a) Existing Liens disclosed on SCHEDULE 7.1, other than those
          Liens shown as items 2.A), B) and C) on such Schedule, provided that
          the obligations secured thereby are not increased;

          2.7  SECTION 7.1 (LIENS; NEGATIVE PLEDGES). SECTION 7.1 of the Credit
Agreement is amended to include clauses (m) and (n) to read as follows:

               (m) A Lien on cash collateral in favor of by BT Commercial
          Corporation to secure the TriNet Letter of Credit; and

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               (n) A Lien on shares of capital stock of any Lender that is
          organized as a cooperative which are required to be pledged by the
          Borrower, as approved by the Agent in its reasonable discretion.

          2.8  SECTION 7.3 (LIMITATIONS ON INDEBTEDNESS; CONTINGENT
OBLIGATIONS).  SECTION 7.3 of the Credit Agreement is amended to include clause
(j) to read as follows:

               (j) The TriNet Letter of Credit, without any extension thereof.

          2.9  SECTION 7.6 (DIVIDENDS).  SECTION 7.6 of the Credit Agreement is
deleted in its entirety and is replaced with the following:

               7.6  DIVIDENDS. The Borrower and its Subsidiaries may not
          declare, make, pay or set apart any funds for the payment of any
          dividends or any other distribution with respect to their Stock or to
          their shareholders on the basis of their status as shareholders, make
          any payment on account of, or set apart assets for a sinking or other
          analogous fund for, the purchase, redemption, retirement or other
          acquisition of their Stock, whether now or hereafter outstanding, or
          make any other distribution in respect thereof to their shareholders
          on the basis of their status as shareholders, either directly or
          indirectly, whether in cash or property or obligations of the Borrower
          or such Subsidiary, except (a) Patronage Dividends, (b) redemption by
          the Borrower of its Class A Shares and Class B Shares as required by
          the Bylaws of the Company as in effect on the Closing Date, (c)
          dividends or other distributions made by a Subsidiary of the Borrower
          to the Borrower or to a Guarantor, and (d) purchase of Class B Shares
          of the Borrower for a price equal to or less than the Discounted Value
          of the Class B Shares, provided that the Requisite Lenders shall have
          first approved such purchase (which shall not be unreasonably withheld
          or delayed); provided, however, that upon the occurrence and during
          the continuation of an Event of Default, the Borrower may make such
          dividends and distributions permitted hereby only to the extent
          necessary to maintain its status as a cooperative under Subchapter T
          of the Code.

     3.  LIMITATION OF AMENDMENTS.

          3.1  The amendments set forth in SECTION 2, above, are effective for
the purposes set forth herein and shall be limited precisely as written and
shall not be deemed to (i) be a consent to any amendment, waiver or modification
of any other term or condition of any Loan Document, or (ii) otherwise prejudice
any right or remedy which

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the Lenders or the Agent may now have or may have in the future under or in
connection with any Loan Document.

          3.2  This Amendment shall be construed in connection with and as part
of the Loan Documents and all terms, conditions, representations, warranties,
covenants and agreements set forth in the Loan Documents, except as herein
amended, are hereby ratified and confirmed and shall remain in full force and
effect.

     4.  REPRESENTATIONS AND WARRANTIES.  In order to induce the Lenders and the
Agent to enter into this Amendment, the Borrower hereby represents and warrants
to each Lender and the Agent as follows:

          4.1  Immediately after giving effect to this Amendment (i) the
representations and warranties contained in the Loan Documents (except to the
extent such representations and warranties relate to an earlier date, in which
case they are true and correct as of such date) are true, accurate and complete
in all material respects as of the date hereof and (ii) no Potential  Event of
Default or Event of Default has occurred and is continuing;

          4.2  The Borrower has the corporate power and authority to execute and
deliver this Amendment and to perform its obligations under the Credit
Agreement, as amended by this Amendment;

          4.3  The articles of incorporation, bylaws and other organizational
documents of the Borrower delivered to each Lender on the Closing Date remain
true, accurate and complete and have not been amended, supplemented or restated
and are and continue to be in full force and effect;

          4.4  The execution and delivery by the Borrower of this Amendment and
the performance by Borrower of its obligations under the Credit Agreement, as
amended by this Amendment, have been duly authorized by all necessary corporate
action on the part of the Borrower;

          4.5  The execution and delivery by the Borrower of this Amendment and
the performance by the Borrower of its obligations under the Credit Agreement,
as amended by this Amendment, do not and will not contravene (i) any law or
regulation binding on or affecting the Borrower, (ii) the articles of
incorporation or bylaws of the Borrower, (iii) any order, judgment or decree of
any court or other governmental or public body or authority, or subdivision
thereof, binding on the Borrower, or (iv) any contractual restriction with a
Person other than an Affiliate binding on the Borrower;

          4.6  The execution and delivery by the Borrower of this Amendment and
the performance by the Borrower of its obligations under the Credit Agreement,
as amended by this Amendment, do not require any order, consent, approval,
license, authorization or validation of, or filing, recording or registration
with, or exemption by any governmental or public body or authority, or
subdivision thereof, binding on the Borrower, except as already has been
obtained or made; and

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          4.7  This Amendment has been duly executed and delivered by the
Borrower and is the binding obligation of the Borrower, enforceable against it
in accordance with its terms, except as such enforceability may be limited by
bankruptcy, insolvency, reorganization, liquidation, moratorium or other similar
laws of general application and equitable principles relating to or affecting
creditors' rights.

    5.  COUNTERPARTS.  This Amendment may be executed in any number of
counterparts and all of such counterparts taken together shall be deemed to
constitute one and the same instrument.

    6.  EFFECTIVENESS.  This Amendment shall be deemed effective upon the
satisfaction of all of the following conditions precedent:

          6.1  AMENDMENT.  The Borrower, each Lender and the Agent shall have
duly executed and delivered this Amendment to the Agent.

          6.2  ACKNOWLEDGMENT OF AMENDMENT AND REAFFIRMATION OF GUARANTIES.  The
Agent shall have received the Acknowledgment of Amendment and Reaffirmation of
Guaranties, duly executed and delivered by each Guarantor to the Agent.

    7.  GOVERNING LAW.  THIS AMENDMENT SHALL BE GOVERNED BY AND SHALL BE
CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

                    [Remainder of Page Intentionally Blank]

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<PAGE>
 
    IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed and delivered as of the date first written above.

BORROWER                                 CERTIFIED GROCERS OF CALIFORNIA, LTD.,
                                         a California corporation


                                         By: /s/ David A. Woodward
                                            ----------------------------
                                            David A. Woodward
                                            Treasurer

AGENT AND                                COOPERATIEVE CENTRALE RAIFFEISEN-
 LENDER                                  BOERENLEENBANK B.A., "RABOBANK
                                         NEDERLAND", NEW YORK BRANCH,
                                         as the Agent and as a Lender


                                         By: /s/ Dana W. Hemenway
                                            ----------------------------
                                         Name:  Dana W. Hemenway
                                              --------------------------
                                         Title: Vice President
                                               -------------------------


                                         By: /s/ W. Jeffrey Vollack
                                            ----------------------------
                                         Name: W. Jeffrey Vollack
                                              --------------------------
                                         Title: Senior Credit Officer
                                               -------------------------
                                                Senior Vice President
                                               -------------------------
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<PAGE>
 
                          ACKNOWLEDGMENT OF AMENDMENT
                        AND REAFFIRMATION OF GUARANTIES


     SECTION 1.   Each Guarantor hereby acknowledges and confirms that it
has reviewed and approved the terms and conditions of the Amendment No. 1 to
Revolving Credit Agreement dated as of even date herewith (the "Amendment").

     SECTION 2.   Each Guarantor hereby consents to the Amendment and
agrees that its respective Guaranty relating to the Obligations of the Borrower
under the Credit Agreement shall continue in full force and effect, shall be
valid and enforceable and shall not be impaired or otherwise affected by the
execution of the Amendment or any other document or instrument delivered in
connection herewith.

     SECTION 3.   Each Guarantor severally represents and warrants that,
after giving effect to the Amendment, all representations and warranties
contained in its respective Guaranty are true, accurate and complete as if made
the date hereof.

Dated as of  May 1, 1998

GUARANTORS:                              CROWN GROCERS, INC.


                                         By: /s/ David A. Woodward
                                            --------------------------
                                             David A. Woodward
                                             Treasurer

                                         GROCER DEVELOPMENT CENTER, INC.


                                         By: /s/ David A. Woodward
                                            --------------------------
                                             David A. Woodward
                                             Treasurer

                                         GROCERS EQUIPMENT COMPANY


                                         By: /s/ David A. Woodward
                                            --------------------------
                                             David A. Woodward
                                             Treasurer

                                       8
<PAGE>
 
                                        GROCERS GENERAL MERCHANDISE COMPANY


                                        By: /s/ David A. Woodward
                                            --------------------------
                                             David A. Woodward
                                             Treasurer

                                        GROCERS AND MERCHANTS MANAGEMENT COMPANY


                                        By: /s/ David A. Woodward
                                            --------------------------
                                             David A. Woodward
                                             Treasurer

                                        GROCERS SPECIALTY COMPANY


                                        By: /s/ David A. Woodward
                                            --------------------------
                                             David A. Woodward
                                             Treasurer

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