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                                                                     Exhibit 4.3

                             SUPPLEMENTAL INDENTURE

            This Supplemental Indenture (this "Supplemental Indenture"), dated
as of April 10, 2001, by and among Casa Trucking, Inc., Crystal Farms
Refrigerated Distribution Company, Farm Fresh Foods of Nevada, Inc., Kohler Mix
Specialties, Inc., Kohler Mix Specialties of Connecticut, Inc., M.G. Waldbaum
Company, Michael Foods of Delaware, Inc., Midwest Mix, Inc., Minnesota Products,
Inc., Northern Star Co., Papetti Electroheating Corporation, Papetti's Hygrade
Egg Products, Inc., WFC, Inc. and Wisco Farm Cooperative (each a "Guaranteeing
Subsidiary" and, collectively, the "Guaranteeing Subsidiaries" ), each of which
is a direct or indirect subsidiary of Michael Foods, Inc., a Minnesota
corporation (the "Company"), the Company and BNY Midwest Trust Company, as
trustee under the Indenture referred to below (the "Trustee").

                               W I T N E S S E T H

            WHEREAS, Michael Foods Acquisition Corp. ("Acquisition") has
heretofore executed and delivered to the Trustee an indenture (the "Indenture"),
dated as of March 27, 2001 providing for the issuance of an aggregate principal
amount of up to $300 million of 11 3/4% Senior Subordinated Notes due 2011 (the
"Notes");

            WHEREAS, pursuant to the Merger, all of the obligations of
Acquisition under the Indenture will become obligations of the Company;

            WHEREAS, the Indenture provides that under certain circumstances
each Guaranteeing Subsidiary shall execute and deliver to the Trustee a
supplemental indenture pursuant to which such Guaranteeing Subsidiary shall
unconditionally guarantee all of the Company's obligations under the Notes and
the Indenture on the terms and conditions set forth herein and in the Indenture;
and

            WHEREAS, pursuant to Section 9.01 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
Company, each 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. Assumption of Obligations. Michael Foods, Inc., a Minnesota
corporation, as successor by merger to M-Foods Acquisition Corp., a Minnesota
corporation ("Acquisition"), hereby expressly assumes all of the respective
obligations of Acquisition as issuer of the Notes under the Indenture.

            3. Agreement to Guarantee. Each of the Guaranteeing Subsidiaries
hereby agrees to become subject to the terms of the Indenture as a Guarantor.

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            4. Incorporation of Terms of Indenture. The obligations of the
Guaranteeing Subsidiaries under the Note Guarantees shall be governed in all
respects by the terms of the Indenture and shall constitute a Note Guarantee
thereunder. Each of the Guaranteeing Subsidiaries shall be bound by the terms of
the Indenture as they relate to the Note Guarantees.

            5. 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 Note 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. Such waiver may
not be effective to waive liabilities under the federal securities laws and it
is the view of the SEC that such a waiver is against public policy.

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

            7. 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.

            8. Effect of Headings. The Section headings herein are for
convenience only and shall not affect the construction hereof.

            9. 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 and attested, all as of the date first above
written.

Dated: April 10, 2001

                              FARM FRESH FOODS OF NEVADA, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              KOHLER MIX SPECIALTIES OF CONNECTICUT,
                              INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              MICHAEL FOODS OF DELAWARE, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              CASA TRUCKING, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              CRYSTAL FARMS REFRIGERATED
                              DISTRIBUTION CO.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary

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                              KOHLER MIX SPECIALTIES, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              MIDWEST MIX, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              MINNESOTA PRODUCTS, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              PAPETTI'S HYGRADE EGG PRODUCTS, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              NORTHERN STAR CO.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              M. G. WALDBAUM COMPANY

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary

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                              PAPETTI ELECTROHEATING CORPORATION

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              WFC, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              WISCO FARM COOPERATIVE

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              MICHAEL FOODS, INC.

                              By:   /s/ Jeffrey M. Shapiro
                                    ------------------------------
                                    Name:   Jeffrey M. Shapiro
                                    Title:  Secretary


                              BNY MIDWEST TRUST COMPANY, AS TRUSTEE

                              By:   /s/ D.G. Donovan
                                    ------------------------------
                                    Name:   D.G. Donovan
                                    Title:  Assistant Vice President