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                                                            Loan No. B051T05C

                         REVOLVING TERM LOAN SUPPLEMENT

      THIS SUPPLEMENT to the Master Loan Agreement dated September 15, 1995
(the "MLA"), is entered into as of May 17, 2001, between CoBANK, ACB
("CoBank") and SOUTH DAKOTA SOYBEAN PROCESSORS, VOLGA, SOUTH DAKOTA (the
"Company"), and amends and restates the Supplement dated August 14, 2000 and
numbered B051T05B.

      SECTION 1. THE REVOLVING TERM LOAN COMMITMENT. On the terms and conditions
set forth in the MLA and this Supplement, CoBank agrees to make loans to the
Company during the period set forth below in an aggregate principal amount not
to exceed, at any one time outstanding, $16,000,000.00, minus the amount
scheduled to be repaid during the period set forth below in Section 5 at any one
time outstanding (the "Commitment"). Within the limits of the Commitment, the
Company may borrow, repay and reborrow.

      SECTION 2. PURPOSE.  The purpose of the Commitment is to provide
working capital to the Company.

      SECTION 3. TERM. The term of the Commitment shall be from May 17, 2001,
up to but not including March 20, 2009, or such later date as CoBank may, in
its sole discretion, authorize in writing.

      SECTION 4.  INTEREST. The Company agrees to pay interest on the
unpaid principal balance of each loan in accordance with one or more of
the following interest rate options, as selected by the Company:

      (A) VARIABLE RATE OPTION. At a rate per annum equal at all times to the
rate of interest established by CoBank on the first Business Day of each week.
The rate established by CoBank may not exceed CoBank's National Variable Rate
(as hereinafter defined) on that day and shall be effective until the first
Business Day of the next week. Each change in the rate shall be applicable to
all balances subject to this option and information about the then current rate
shall be made available upon telephonic request. For purposes hereof, the
National Variable Rate shall mean the rate of interest established by CoBank
from time to time as its National Variable Rate, which Rate is intended by
CoBank to be a reference rate and not its lowest rate. The National Variable
Rate will change on the date established by CoBank as the effective date of any
change therein and CoBank agrees to notify the Company promptly after any such
change.

      (B) FIXED RATE OPTION. At a fixed rate per annum to be quoted by CoBank in
its sole discretion in each instance. Under this option, rates may be fixed on
such balances and for such periods as may be agreeable to CoBank in its sole
discretion in each instance.

The Company shall select the applicable rate option at the time it requests each
loan hereunder and may, on any Business Day, elect to convert balances bearing
interest at the variable rate option to the fixed rate option. In addition,
prior to the expiration of any fixed rate period, the Company may, subject to
Section 12 of the MLA, convert any fixed rate balance to the variable

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rate option or refix the rate at a new rate to be quoted by CoBank. Upon the
expiration of any fixed rate period, the Company may, subject to the terms
hereof, refix the rate or convert the rate to the variable rate option. In
the absence of any such election, interest shall automatically accrue at the
variable rate option. All elections provided for herein shall be made
telephonically or in writing and must be received by 12:00 Noon Company's
local time. Interest shall be calculated on the actual number of days each
loan is outstanding on the basis of a year consisting of 360 days and shall
be payable monthly in arrears by the 20th day of the following month.

      SECTION 5.  PROMISSORY NOTE. The Company promises to repay on the
dates set forth below, the outstanding principal, if any, that is in
excess of the listed amounts:

<Table>
<Caption>
            PAYMENT DATE                   REDUCING COMMITMENT AMOUNT
            ------------                   --------------------------
<S>                                        <C>
            March 20, 2002                        $14,900,000.00
            September 20, 2002                    $13,800,000.00
            March 20, 2003                        $12,700,000.00
            September 20, 2003                    $11,600,000.00
            March 20, 2004                        $10,500,000.00
            September 20, 2004                    $ 9,400,000.00
            March 20, 2005                        $ 8,300,000.00
            September 20, 2005                    $ 7,200,000.00
            March 20, 2006                        $ 6,100,000.00
            September 20, 2006                    $ 5,000,000.00
            March 20, 2007                        $ 3,900,000.00
            September 20, 2007                    $ 2,800,000.00
            March 20, 2008                        $ 1,700,000.00
            September 20, 2008                    $   600,000.00

</Table>

followed by a final installment in an amount equal to the remaining unpaid
principal balance of the loan on March 20, 2009. If any installment due date is
not a day on which CoBank is open for business, then such payment shall be made
on the next day on which CoBank is open for business. In addition to the above,
the Company promises to pay interest on the unpaid principal balance hereof at
the times and in accordance with the provisions set forth in Section 4 hereof.
This note replaces and supersedes, but does not constitute payment of the
indebtedness evidenced by, the promissory note set forth in the Supplement being
amended and restated hereby.

      SECTION 6. PREPAYMENT. The loans may be prepaid in whole or in part on one
CoBank business day's prior written notice. During the term of the Commitment,
prepayments shall be applied to such balances, fixed or variable, as the Company
shall specify. After the expiration of the term of the Commitment, prepayments
shall, unless CoBank otherwise agrees, be applied to principal installments in
the inverse order of their maturity and to such balances, fixed or variable, as
CoBank shall specify.

      SECTION 7. COMMITMENT FEE. In consideration of the Commitment, the Company
agrees to pay to CoBank a commitment fee on the average daily unused portion of
the

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Commitment at the rate of 1/2 of 1% per annum (calculated on a 360 day
basis), payable monthly in arrears by the 20th day following each month. Such
fee shall be payable for each month (or portion thereof) occurring during the
original or any extended term of the Commitment.

      IN WITNESS WHEREOF, the parties have caused this Supplement to be executed
by their duly authorized officers as of the date shown above.

CoBANK, ACB                            SOUTH DAKOTA SOYBEAN PROCESSORS

By:   /s/ Rebecca S. Kennedy           By:   /s/ Connie Kelly
   ---------------------------            ----------------------------

Title: Assistant Corporate Secretary   Title:      CFO
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