<PAGE>
                                                                    EXHIBIT 10.1


                   SECOND AMENDMENT TO CREDIT AND SECURITY AGREEMENT

        THIS SECOND AMENDMENT (this "Amendment"), dated as of January 13, 1997,
amends and modifies a certain Credit and Security Agreement, dated as of
December 19, 1995 (as the same may be amended, replaced, restated and/or
supplemented from time to time, the "Credit Agreement"), between FBS BUSINESS
FINANCE CORPORATION, a Delaware corporation (the "Lender"), and CRYENCO, INC., a
Colorado corporation, CRYENCO SCIENCES, INC., a Delaware corporation and
CRYENEX, INC., a Delaware corporation (collectively and/or individually the
"Borrower"). Terms not otherwise expressly defined herein shall have the
meanings set forth in the Credit Agreement.

                              PRELIMINARY STATEMENT

        WHEREAS, an event has occurred constituting an Event of Default under
the terms of the Credit Agreement, which the Borrower has requested the Lender
to waive; and

        WHEREAS, the Lender has agreed to waive the Event of Default identified
herein, subject to the terms and conditions set forth in this Amendment.

        NOW, THEREFORE, for value received, the Borrower and the Lender agree as
follows:

        SECTION 1. CAPITALIZED TERMS. Capitalized terms used herein and not
otherwise defined herein shall have the meanings assigned to them in the Credit
Agreement, unless the context shall otherwise require.

        SECTION 2.    DEFAULT AND WAIVER.

        2.1 Event of Default. Under Section 9.3 of Supplement A to the Credit
        Agreement, the Borrower was to maintain a ratio, as of the last day of
        each fiscal quarter, of the consolidated EBITDA of the Borrower during
        the four consecutive fiscal quarters then ending, to the sum of their
        consolidated unfinanced capital expenditures, cash taxes, interest
        payments, dividends and mandatory debt retirement payments during the
        four consecutive fiscal quarters then ending, of not less than 1.15:1
        from September 1, 1996 through August 31, 1997. The Borrower has advised
        the Lender that as of November 30, 1996, the foregoing ratio was 1.05:1,
        in violation of Section 9.3 of Supplement A.

        2.2 Waiver. Upon the date upon which this Amendment becomes effective,
        the Lender hereby waives the Event of Default described in the preceding
        Section 2.1. The waiver set forth herein shall not constitute a waiver
        by the Lender of any Unmatured Event of Defaults or any other Event of
        Default, if any, under the Credit Agreement, and shall not be, and shall
        not be deemed to


                                              -1-

<PAGE>

<PAGE>


        be, a course of action with respect thereto upon which
        the Borrower may rely in the future and the Borrower hereby expressly
        waives any claim to such effect.

        SECTION 3. REPRESENTATIONS; NO DEFAULT. The Borrower hereby represents
that on and as of the date hereof and after giving effect to this Amendment (a)
all of the representations and warranties contained in the Credit Agreement are
true, correct and complete in all respects as of the date hereof as though made
on and as of such date, except for changes permitted by the terms of the Credit
Agreement, and (b) there will exist no Unmatured Event of Default or Event of
Default under the Credit Agreement as amended by this Amendment on such date
which has not been waived by the Lender. The Borrower represents and warrants
that the Borrower has the power and legal right and authority to enter into this
Amendment and has duly authorized as appropriate the execution and delivery of
the Amendment Document and other agreements and documents executed and delivered
by the Borrower in connection herewith or therewith by proper corporate action,
and neither this Amendment nor any of the agreements contained herein contravene
or constitute a default under any agreement, instrument or indenture to which
the Borrower is a party or a signatory or a provision of the Borrower's Articles
of Incorporation, Bylaws or, to the best of the Borrower's knowledge any other
agreement or requirement of law, or result in the imposition of any Lien on any
of its property under any agreement binding on or applicable to the Borrower or
any of its property except, if any, in favor of the Lender. The Borrower
represents and warrants that no consent, approval or authorization of or
registration or declaration with any Person, including without limitation, any
governmental authority, is required in connection with the execution and
delivery by the Borrower of this Amendment or other agreements and documents
executed and delivered by the Borrower in connection therewith or the
performance of obligations of the Borrower therein described, except for those
which the Borrower has obtained or provided and as to which the Borrower has
delivered certified copies of documents evidencing each such action to the
Lender.

        The Borrower warrants that no events have taken place and no
circumstances exist at the date hereof which would give the Borrower assert a
defense, offset or counterclaim to any of the Obligations.

        SECTION 4. AFFIRMATION, FURTHER REFERENCES. The Lender and the Borrower
each acknowledge and affirm that the Credit Agreement, as hereby amended, is
hereby ratified and confirmed in all respects and all terms, conditions and
provisions of the Credit Agreement as amended prior to the date of this
Amendment, shall remain unmodified and in full force and effect except as
amended by this Amendment. All references in any document or instrument to the
Credit Agreement are hereby amended and shall refer to the Credit Agreement as
amended from time to time.



                                 -2-


<PAGE>
<PAGE>


        SECTION 5. SEVERABILITY. Whenever possible, each provision of this
Amendment and the other Amendment Documents and any other statement, instrument
or transaction contemplated hereby or thereby or relating hereto or thereto
shall be interpreted in such manner as to be effective, valid and enforceable
under the applicable law of any jurisdiction, but if any provision of this
Amendment, the other Amendment Documents or any other statement, instrument or
transaction contemplated hereby or thereby or relating hereto or thereto shall
be held to be prohibited, invalid or unenforceable under the applicable law,
such provision shall be ineffective in such jurisdiction only to the extent of
such prohibition, invalidity or unenforceability, without invalidating or
rendering unenforceable the remainder of such provision or the remaining
provisions of this Amendment, the other Amendment Documents or any other
statement, instrument or transaction contemplated hereby or thereby or relating
hereto or thereto in such jurisdiction, or affecting the effectiveness, validity
or enforceability of such provision in any other jurisdiction.

        SECTION 6. SUCCESSORS. This Amendment shall be binding upon the Borrower
and the Lender and their respective successors and assigns, and shall inure to
the benefit of the Borrower and the Lender and the successors and assigns of the
Lender.

        SECTION 7. LEGAL EXPENSES. The Borrower agrees to reimburse the Lender,
upon execution of this Amendment, for all reasonable out-of-pocket expenses
(including attorneys' fees and legal expenses of Dorsey & Whitney LLP, counsel
for the Lender) incurred in connection with the Credit Agreement, including in
connection with the negotiation, preparation and execution of this Amendment and
all other documents negotiated, prepared and executed in connection with this
Amendment, which obligations of the Borrower shall survive any termination of
the Credit Agreement.

        SECTION 8.    HEADINGS.  The Headings of various sections of this
Amendment have been inserted for reference only and shall not be deemed to be a
part of this Amendment.

        SECTION 9. COUNTERPARTS. This Amendment may be executed in several
counterparts as deemed necessary and convenient, each of which, when so
executed, shall be deemed an original, provided that all such counterparts shall
be regarded as one and the same document, and any party to the Amendment
Documents may execute any such agreement by executing a counterpart of such
agreement.

        SECTION 10.   GOVERNING LAW.  The Amended Documents shall be governed by
the internal laws of the State of Minnesota, without giving effect to conflict
of law principles thereof.


                                 -3-


<PAGE>
<PAGE>

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized as of the date
first written above.

                                               FBS BUSINESS FINANCE CORPORATION

                                               By /s/ William C. Phelps
                                                  ------------------------------
                                                    Its Vice President
                                                  ------------------------------

                                               CRYENCO, INC.

                                               By /s/ James A. Raabe
                                                  ------------------------------
                                                   Its CFO
                                                  ------------------------------

                                               CRYENCO SCIENCES, INC.

                                               By /s/ James A. Raabe
                                                  ------------------------------
                                                    Its CFO
                                                  ------------------------------

                                               CRYENEX, INC.

                                               By /s/ James A. Raabe
                                                  ------------------------------
                                                    Its CFO
                                                  ------------------------------

<PAGE>