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                                                                   Exhibit 10.11

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BANK ONE

                                                   Amendment to Credit Agreement

This agreement is made and entered into on May 30, 2003, to be effective as of
May 30, 2003 by and between Alltech Associates, Inc. (the "Borrower") and Bank
One, NA, with its main office in Chicago, IL (the "Bank"), and its successors
and assigns.

WHEREAS, the Borrower and the Bank entered into a credit agreement dated May 30,
2002, as amended (if applicable) (the "Credit Agreement"); and

WHEREAS, the Borrower has requested and the Bank has agreed to amend the Credit
Agreement as set forth below;

NOW, THEREFORE, in mutual consideration of the agreements contained herein and
for other good and valuable consideration, the parties agree as follows:

l.   DEFINED TERMS. Capitalized terms not defined herein shall have the meaning
     ascribed in the Credit Agreement.

2.   MODIFICATION OF CREDIT AGREEMENT. The Credit Agreement is hereby amended as
     follows:

     2.1  From and after the date of this agreement, the following provision is
          hereby added to the Credit Agreement as part of Section 2.
          Definitions:

          2.16 "Capital Expenditures" means any expenditure or the occurrence of
               any obligation or liability by the Borrower for any asset which
               is classified as a capital asset.

     2.2  From and after the date of this agreement, the provision in the Credit
          Agreement under Section 5. Negative Covenants Subsection 5.2 A.
          captioned "Dividends" is hereby amended and restated to read as
          follows:

          A.   Dividends. Acquire or retire any of its shares of capital stock,
               or declare or pay dividends or make any other distributions upon
               any of its shares of capital stock, except in the absence of the
               occurrence of any default, dividends in its capital stock.

     2.3  From and after the date of this agreement, the provision in the Credit
          Agreement under Section 5. Negative Covenants Subsection 5.2 J.
          captioned "Transfer of Ownership" is hereby deleted.

     2.4  From and after the date of this agreement, the provision in the Credit
          Agreement under Section 5. Negative Covenants Subsection 5.2 M.
          captioned "Debt Service Coverage Ratio" is hereby amended and restated
          to read as follows:

          M.   Debt Service Coverage Ratio. Permit as of each fiscal quarter
               end, Borrower and its subsidiaries' combined ratio of net income,
               plus interest expense, plus depreciation expense, plus
               amortization expense, plus impairment of goodwill, minus
               dividends, plus or minus changes in the LIFO reserve, plus or
               minus changes within deferred taxes, minus unfunded Capital
               Expenditures, for the twelve month period then ending to
               principal on long term debt, plus capital lease payments, plus
               scheduled principal and interest payments on Subordinated Debt,
               plus interest payments, to be less than 1.00 to 1.00.

3.   RATIFICATION. The Borrower ratifies and reaffirms the Credit Agreement and
     the Credit Agreement shall remain in full force and effect as modified
     herein.

4.   BORROWER REPRESENTATIONS AND WARRANTIES. The Borrower represents and
     warrants that (a) the representations and warranties contained in the
     Credit Agreement are true and correct in all material respects as of the
     date of this agreement, (b) no condition, act or event which could
     constitute an event of default under the Credit Agreement or any promissory
     note or credit facility executed in reference to the Credit Agreement
     exists, and (c) no condition, event, act or omission has occurred, which,
     with the giving of notice or passage of time, would constitute an event of
     default under the Credit Agreement or any promissory note or credit
     facility executed in reference to the Credit Agreement.

5.   FEES AND EXPENSES. The Borrower agrees to pay all fees and out-of-pocket
     disbursements incurred by the Bank in connection with this agreement,
     including legal fees incurred by the Bank in the preparation, consummation,
     administration and enforcement of this agreement.

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6.   EXECUTION AND DELIVERY. This agreement shall become effective only after it
     is fully executed by the Borrower and the Bank.

7.   ACKNOWLEDGEMENTS OF BORROWER. The Borrower acknowledges that as of the date
     of this agreement it has no offsets with respect to all amounts owed by the
     Borrower to the Bank arising under or related to the Credit Agreement on or
     prior to the date of this agreement. The Borrower fully, finally and
     forever releases and discharges the Bank and its successors, assigns,
     directors, officers, employees, agents and representatives from any and all
     claims, causes of action, debts and liabilities, of whatever kind or
     nature, in law or in equity, of the Borrower, whether now known or unknown
     to the Borrower, which may have arisen in connection with the Credit
     Agreement or the actions or omissions of the Bank related to the Credit
     Agreement on or prior to the date hereof. The Borrower acknowledges and
     agrees that this agreement is limited to the terms outlined above, and
     shall not be construed as an agreement to change any other terms or
     provisions of the Credit Agreement. This agreement shall not establish a
     course of dealing or be construed as evidence of any willingness on the
     Bank's part to grant other or future agreements, should any be requested.

8.   NOT A NOVATION. This agreement is a modification only and not a novation.
     Except for the above-quoted modification(s), the Credit Agreement, any
     loan agreements, credit agreements, reimbursement agreements, security
     agreements, mortgages, deeds of trust, pledge agreements, assignments,
     guaranties, instruments or documents executed in connection with the Credit
     Agreement, and all the terms and conditions thereof, shall be and remain in
     full force and effect with the changes herein deemed to be incorporated
     therein. This agreement is to be considered attached to the Credit
     Agreement and made a part thereof. This agreement shall not release or
     affect the liability of any guarantor of any promissory note or credit
     facility executed in reference to the Credit Agreement or release any owner
     of collateral granted as security for the Credit Agreement. The validity,
     priority and enforceability of the Credit Agreement shall not be impaired
     hereby. To the extent that any provision of this agreement conflicts with
     any term or condition set forth in the Credit Agreement, or any document
     executed in conjunction therewith, the provisions of this agreement shall
     supersede and control. The Bank expressly reserves all rights against all
     parties to the Credit Agreement.

Bank:                                      Borrower:

Bank One, NA, with its main office in      Alltech Associates, Inc.
Chicago, IL


By  /s/ Illegible                           By: /s/ Geoffry Matlin
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    Illegible                   VP             Geoffry Matlin
    Printed Name                Title          Printed Name                Title

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