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                                                                    EXHIBIT 10.4

                          BIO-ENGINEERED FOODS, INC.
                          --------------------------
                           1993 STOCK INCENTIVE PLAN
                           -------------------------

1.   PURPOSE.

     1.1  Incentive to Employees. This 1993 Stock Incentive Plan (the "Plan") is
          ----------------------
intended to provide incentive to, and to encourage stock ownership by, selected 
employees, officers, directors and consultants of BIO-ENGINEERED FOODS, INC., a 
Delaware corporation (the "Company"), any Subsidiary (as defined below) and any 
Parent (as defined below), so that such employees, officers, directors and 
consultants may acquire a proprietary interest in, or increase their proprietary
interest in, the Company. For the purposes of the Plan, the terms "Subsidiary" 
and "Parent" shall mean any present or future corporation which would be a 
"subsidiary corporation" or a "parent corporation," respectively, of the 
Company, as those terms are defined in Section 424 of the Internal Revenue Code 
of 1986, as amended (the "Code").

     1.2  Stock Incentive Awards. The Plan provides for the grant of options to 
          ----------------------
purchase shares of the Company's authorized but unissued Common Stock ("Shares")
to selected officers, employees, directors and consultants of the Company
(sometimes collectively referred to herein as "offerees", "grantees" or
"optionees"). Options granted under the Plan may include non-statutory options
and options intended to qualify as "incentive stock options", as that term is
defined in Section 422 of the Code ("incentive stock options").

2.   ADMINISTRATION.

     2.1  Board of Directors. The Plan shall be administered by the Board of 
          ------------------
Directors of the Company (the "Board") or by a Committee as defined in Section 
2.2 below. The interpretation and construction by the Board or the Committee of 
any provision of the Plan, or of any agreement or option issued or executed 
under or pursuant to the Plan, shall be final and binding upon optionees 
hereunder. No member of the Board or the Committee shall be liable for any 
action or determination undertaken or made in good faith with respect to the 
Plan or any agreement or option issued or executed under or pursuant to the 
Plan.

     2.2  Committee of the Board. The Board may, in its sole and absolute 
          ----------------------
discretion, delegate any or all of its duties and authority with respect to the 
Plan to a committee of at least two (2) Directors of the Company (the 
"Committee") to be appointed by and to serve at the pleasure of the Board. No 
person eligible to receive options under this Plan shall vote as a member of the
Board or the Committee upon his or her own option award. Once appointed, the 
Committee shall continue to serve until otherwise directed by the Board. From 
time to time, the Board may increase or decrease
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the size of the Committee, add additional members to, remove members (with or 
without cause) from, appoint new members in substitution therefor, and fill 
vacancies, however caused, in the Committee. The Committee shall act pursuant to
a vote of the majority of its members, whether present in person or by 
telephonic means at a meeting of the Committee, or by the unanimous written 
consent of its members, and minutes shall be kept of all of its meetings and 
copies thereof shall be provided to the Board. Subject to the limitations 
prescribed by the Plan and the Board, the Committee may establish and follow 
such rules and regulations for the conduct of its business as it may determine 
to be advisable.

     2.3 Administrative Powers. Subject to the provisions of the Plan, the 
         ---------------------
Board or the Committee, as the case may be (the "Administrator"), shall have
authority to take the following actions:

         (a) to construe and interpret the Plan and apply its provisions;

         (b) to promulgate, amend and rescind rules and regulations relating to 
the administration of the Plan;

         (c) to authorize any person to execute, on behalf of the Company, any 
instrument required to carry out the purposes of the Plan;

         (d) to determine when options are to be granted under the Plan;

         (e) from time to time to select those officers, employees, directors 
and consultants to whom options shall be granted from among the eligible 
officers, employees, directors and consultants (as determined pursuant to 
Section 3 below) of the Company, any Subsidiary or Parent;

         (f) to determine the number of Shares to be made subject to each 
option;

         (g) to prescribe the terms and condition of each option, including, 
without limitation, the exercise price and medium of payment, to determine 
whether such option is to be classified as an incentive stock option or as a 
non-statutory stock option, and to specify the provisions of the stock option 
agreement relating to such option;

         (h) to amend any outstanding stock option agreement for the purpose of 
modifying the exercise price as the case may be, subject to applicable legal 
restrictions and to the consent of the other party to such agreement;

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         (i)  to determine the duration and purpose of leaves of absences 
which may be granted to employees without constituting termination of their 
employment for purposes of the Plan; and
   
         (j)  to make any and all other determinations which they 
determine to be necessary or advisable for administration of the Plan.

3.  ELIGIBILITY.

    3.1  General Rule.  Any employee, officer, director or consultant of the 
         ------------
Company, any Subsidiary or Parent, shall be eligible to receive options granted 
under the Plan and may hold more than one option.

    3.2  Limitation with Respect to Incentive Stock Options.
         --------------------------------------------------

         (a)  Limitation to Employees.  No incentive stock option shall be 
              -----------------------
granted under the Plan except to employees (including employees who are 
officers) of the Company, any Subsidiary, or any parent.

         (b)  Limitation on Amount.  The aggregate Fair Market Value (determined
              --------------------
as of the date of grant) of Shares with respect to which incentive stock options
are exercisable for the first time by any one optionee during any calendar 
year (under this Plan and all other stock option plans of the Company) shall not
exceed $100,000.

4.  FAIR MARKET VALUE.

    For purposes of the Plan, "Fair Market Value" of Shares of Common Stock of 
the Company on any date shall mean that amount which the Administrator 
determines in good faith to be the amount which a willing buyer would pay to an 
equally willing seller to purchase such Shares subject to an option or stock 
purchase agreement on such date.

5.  THE STOCK.

    The stock subject to any option granted under the Plan shall be Shares of
the Company's authorized but unissued Common Stock. Subject to adjustment as set
forth in this Section 5, the total number of Shares which may be issued under
the Plan upon exercise of options or other rights to purchase Shares shall not
exceed 250,000 shares of Common Stock; provided, however, that if (a) any
                                       --------  -------
outstanding option shall for any reason expire or terminate unexercised, or (b)
any

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Shares issued under the Plan are repurchased by the Company pursuant to the 
terms of the option agreement or stock purchase agreement under which they were 
issued, then such Shares shall again be available for issuance under the Plan. 
Each time any of the events set forth in Section 6.8(a) or Section 6.8(b) of the
Plan occurs, the number of Shares purchasable under the Plan shall be adjusted 
in the same manner as the number of Shares subject to any outstanding option 
would be adjusted under the provisions of Section 6.8(c) of the Plan.

6.   TERMS AND CONDITIONS OF OPTIONS.

     6.1  Option Agreement. Each option granted under the Plan shall be 
          ----------------
evidenced by an option agreement between the optionee and the Company in the
form from time to time adopted by the Administrator and containing such terms
and conditions which the Administrator deems appropriate; provided such terms
and conditions are not inconsistent with the Plan. The provisions of the various
option agreements entered into under the Plan need not be identical.

     6.2  Exercise Price. Each option agreement shall state the price at which 
          --------------
the Shares subject to the option may be purchased (the "Exercise Price"). In the
case of an incentive stock option, the Exercise Price shall not be less than 
100% of the Fair Market Value of such Shares on the date the option is granted 
(as determined by the Administrator); provided, however, that in the case of an 
                                      --------  -------
incentive stock option granted to a "Ten Percent Shareholder" (as defined 
below), the Exercise Price shall not be less than 110% of the Fair Market Value 
on the date the option is granted (as determined by the Administrator). The 
exercise price of a non-statutory option shall be at the price determined by the
Administrator. For purposes of the Plan, "Ten Percent Shareholder" means a 
person who, on the date of grant by the Administrator of an option to that 
person owns, either directly or through attribution as provided in Section 
424(d) of the Code, capital stock of the Company possessing more than 10% of the
total combined voting power of all classes of stock of his or her employer 
corporation or of any Parent or Subsidiary.

     6.3  Number of Shares. Each option agreement shall state the number of 
          ----------------
Shares which may be purchased upon exercise, and shall specify that the option 
is an incentive stock option or a non-statutory stock option.

     6.4  Term of Option. Each option agreement shall provide that the option 
          --------------
shall terminate at the expiration of the earliest of:

          (a)  that date selected by the Administrator, which shall be not more 
than ten (10) years after the date the option is

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granted or, in the case of an incentive option granted to a Ten Percent 
Shareholder, five (5) years after the date the option is granted;

         (b) thirty 30 days (one hundred eighty (180) days in the case of a 
non-statutory stock option) after the date of termination of the optionee's 
services to or employment with the Company, any Subsidiary or any Parent for any
reason other than those set forth in clauses (c), (d) or (e) below;

         (c) one year after the date of termination of the optionee's employment
with the Company, any Subsidiary or any Parent as a result of the permanent and 
total disability of the optionee;

         (d) one year after the death of the optionee, provided that such death 
occurs during the optionee's employment by the Company or within thirty (30) 
days after termination of such employment other than for cause; and

         (e) in the event that the optionee's employment is terminated (i) 
voluntarily by the optionee, or (ii) for cause (of which the Administrator
shall be the sole judge), all of the optionee's unexercised options shall expire
as of the date of termination;

provided, that the option agreement for any option may provide for shorter 
--------
periods in each of the foregoing instances if so determined by the
Administrator. For the purposes of Section 6.4(c), "permanent and total
disability" shall mean a disability of the type defined in Section 22(e)(3) of
the Code. An individual shall not be considered permanently disabled unless he
or she furnishes proof of the existence of such permanent disability in such
form and manner, and at such times, as the Administrator may require.

     6.5 Transfer of Option. Each option agreement shall provide that the option
         ------------------
shall not be transferable by the optionee otherwise than by will or the laws of 
descent and distribution.

     6.6 Exercise of Option. Each option agreement shall provide that the option
         ------------------
shall not be exercisable during the lifetime of the optionee by any person other
than the optionee. Except as provided in Section 6.12 hereof, each option
granted pursuant to the Plan shall be exercisable, in whole or in part, no
earlier than one year from the date of grant of the option; provided, however,
that a non-statutory option may, at the discretion of the Administrator, become
exercisable beginning six (6) months after the date of grant. At the discretion
of the Administrator, options may be exercisable in installments at a rate of
not less than 20% per year, in which case such installments (if more than one)
shall (to the extent not exercised) accumulate and be exercisable, in whole

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or in part, in any subsequent installment period but in no event later than the 
date of the termination of the option.

       6.7  Investment Purposes.  Unless and until the issuance and sale of the 
            -------------------
Shares acquired by an optionee pursuant to the exercise of options granted 
under the Plan are registered under the Act or any similar subsequent 
legislation, each option agreement under the Plan shall provide that the 
purchase of Shares pursuant to the option agreement shall be for investment 
purposes, and not with a view to resale or distribution other than as permitted 
under the Act. Each option agreement shall further provide that no Shares shall
be purchased or sold thereunder unless and until (a) any then applicable
requirements of state or federal laws and regulatory agencies shall have been
fully complied with to the satisfatction of the Company and its counsel, and (b)
if required to do so by the Company, the optionee shall have executed and
delivered to the Company a stock restriction agreement in such form and
containing such provisions as the Administrator may require.

       6.8  Stock Splits, Etc.  Each option agreement shall provide that, 
            ------------------
subject to any required action by the shareholders of the Company:

            (a)  If outstanding Shares shall be subdivided into a greater number
of Shares, or a dividend in Shares or other securities of the Company 
convertible into or exchangeable for the Shares (in which latter event the 
number of Shares issuable upon the conversion or exchange of such securities 
shall be deemed to have been distributed) shall be paid in respect of the 
Shares, the Exercise Price of any outstanding option in effect immediately 
prior to such subdivision or at the record date of such dividend shall, 
simultaneously with the effectiveness of such subdivision or immediately after 
the record date of such dividend, be proportionately reduced, and conversely, if
the outstanding Shares shall be combined into a small number of Shares, the 
Exercise Price of any outstanding option in effect immediately prior to such 
combination shall, simultaneously with the effectiveness of such combination, be
proportionately increased.

            (b)  In the event the Company at any time, or from time to time, 
shall make or issue, or fix a record date for the determination of holders of 
Shares entitled to receive, a dividend or other distribution payable in 
securities of the Company other than Shares or securities convertible into or 
exchangeable for Shares then and in each such event, provision shall be made so 
that the holders of options shall receive upon exercise thereof, in addition to 
the number of Shares receivable thereupon, the amount of securities of the 
Company which they would have received had their option been exercised on the 
date of such event and had thereafter, during the period from the date of such 
event to and including the date of exercise, retained such securities receivable

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by them as aforesaid during such period, giving application to all adjustments 
called for during such period under this Section 6.8 with respect to the rights 
of the holders of options.

          (c)  When any adjustment is required to be made in the Exercise Price,
the number of Shares purchasable upon the exercise of any outstanding option 
shall be adjusted to that number of Shares determined by (i) multiplying an 
amount equal to the number of Shares purchasable upon the exercise of the option
immediately prior to such adjustment by the Exercise Price in effect immediately
prior to such adjustment, and then (ii) dividing that product by the Exercise 
Price in effect immediately after such adjustment.

          (d)  In the case of any capital reorganization, any reclassification 
of the Shares (other than a change in par value or recapitalization described in
Section 6.8(a) or 6.8(b) hereof), or the consolidation of the Company with, or a
sale of substantially all of the assets of the Company to (which sale is 
followed by a liquidation or dissolution of the Company), or the merger of the 
Company with another person, except as provided in Section 6.12 hereof, the 
holder of any outstanding option shall thereafter be entitled upon exercise of 
the option to purchase the kind and number of Shares or other securities or 
property of the surviving corporation receivable upon such event by a holder of 
the number of Shares which such option entitles the holder to purchase from the 
Company immediately prior to such event. In every such case, appropriate 
adjustment shall be made in the application of the provisions set forth in the 
option agreement and in the Plan with respect to the rights and interests 
thereafter of the optionee, to the end that the provisions set forth in the 
option agreement and in the Plan (including the specified changes and other 
adjustments to the Exercise Price) shall thereafter be applicable in relation to
any Shares or other securities or property thereafter purchasable upon exercise 
of such option.

          (e)  A dissolution or liquidation of the Company shall cause each 
outstanding option to terminate; provided that each optionee shall have the 
                                 --------
right exercisable during a 10-day period ending on the fifth day prior to such 
dissolution or liquidation to exercise his or her option in whole or in part, 
without regard to any installment provisions under his or her option agreement; 
but any exercise of the option which except for the provisions of this Section 
6.8(e) would not then be exercisable, shall be conditioned upon the actual 
occurrence of such dissolution or liquidation, and if such dissolution or 
liquidation does not occur, the optionee's exercise of the option during such 
10-day period shall be null and void, and of no force and effect. For purposes 
of this Section 6.8(e) and subject to the previous sentence, any exercise of the
option by the optionee pursuant to this Section 6.8(e) shall be

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deemed to occur immediately prior to the consummation of any such dissolution or
liquidation.

           (f)  To the extent that the foregoing adjustments relate to stock or 
securities of the Company, such adjustments shall be made by the Administrator, 
whose determination in that respect shall be final, binding and conclusive.

           (g)  Except as expressly provided in this Section 6.8 or in Section 
6.12, no optionee shall have any rights by reason of any subdivision or 
consolidation of shares of stock of any class or the payment of any stock 
dividend or any other increase or decrease in the number of shares of stock of 
any class, and the dissolution, liquidation, merger, consolidation or split-up 
or sale of assets or stock to another corporation, or any issue by the Company 
of shares of stock of any class, or securities convertible into shares of stock
of any class, shall not affect, and no adjustment by reason thereof shall be 
made with respect to, the number of, or Exercise Price for, the shares.

           (h)  The grant of an option pursuant to the Plan shall not affect in
any way the rights or power of the Company to make adjustments, 
reclassification, reorganizations or changes of its capital or business 
structure or to merge, consolidate, dissolve or liquidate, or to sell or 
transfer all or any part of its business or assets.

      6.9  Rights as a Shareholder.  Each option agreement shall provide that 
           ----------------------- 
no optionee or transferee of an option shall have any rights as a shareholder 
with respect to any of the Shares subject to the option until the date of 
issuance of a stock certificate for such Shares.  No adjustment shall be made 
for dividends (ordinary or extraordinary, whether in cash, securities or other 
property) or distribution or other rights for which the record date is prior to
the date such stock certificate is issued, except as provided in Section 6.8 
above.

      6.10 Restrictions on Transfers of Shares.  Each option agreement may 
           -----------------------------------
contain such restrictions on transfer of Shares obtained pursuant to the 
exercise of options as the Administrator may determine including without 
limitation, rights of repurchase and rights of refusal.

      6.11 Modification, Extension, and Renewal of Option.  Subject to the terms
           ----------------------------------------------
and conditions and within the limitations of the Plan and the Code, the 
Administrator may modify (including a modification of the Exercise Price) extend
or renew outstanding options granted under the Plan, or accept the surrender of 
outstanding options (to the extent not previously exercised) and authorize the 
granting of new options in substitution therefor (to the extent not previously 
exercised).  However, no modification of

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an option shall be made without the consent of the optionee which would alter or
impair any rights of the optionee under the option.

     6.12 Acceleration.
          ------------

          (a)  A "Change in Control" for purposes of this Plan shall mean (i) a 
single entity or group of affiliated entities acquires more than 50% of the 
stock of the Company issued and outstanding immediately prior to such 
acquisition; or (ii) shareholders approve the consummation of any merger of the 
Company or any sale or other disposition of all or substantially all of its 
assets, if the shareholders of the Company immediately before such transaction 
own, immediately after consummation of such transaction, equity securities 
(other than options and other rights to acquire equity securities) possessing 
less than 50% of the voting power of the surviving or acquiring corporation.

          (b)  If a Change in Control has occurred or if the Board of Directors 
determines in good faith that a Change in Control is about to occur, the Board 
of Directors may determine that it is necessary or desirable to accelerate the 
options granted hereunder. Upon such determination, all outstanding options will
be immediately exercisable by the holder of the option for the total remaining 
number of Shares covered by the option. Such option may then be exercised by its
respective holder at any time within a period of 30 calendar days following the 
date on which the Board of Directors determines that it is necessary or 
desirable to accelerate the options.

          (c)  Any options subject to acceleration under this Section that are
not exercised during the period of 30 days provided in subsection (b) above
shall be treated as if no Change in Control had occurred and shall be governed
by their original terms. Nevertheless, by a notice to that effect which is
communicated in any reasonable manner to as many of the holders of options as is
feasible and which is communicated before the last day of the 30 day period
created by subsection (b) above, the Board of Directors may provide that any
options accelerated pursuant to this Section 6.12 shall expire at midnight upon
the last day of the 30 day period provided by subsection (b).

7.   PAYMENT FOR SHARES.

     7.1  General Rule. The Exercise Price for any Shares purchased under the 
          ------------
Plan shall be payable in cash, by check or, at the discretion of the 
Administrator, with Shares which are already owned by the optionee and which are
surrendered to the Company in good form for transfer. Such Shares shall be 
valued at their Fair Market Value on the date when the new Shares are purchased 
under the Plan.

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     7.2  Promissory Note.  The Administrator in its sole discretion may specify
          ---------------
in any option agreement entered into hereunder that payment may be made with a
full recourse promissory note executed by the optionee or offeree. Such note
shall bear interest at the rate specified in the option agreement for a term of
no more than five years with interest only payable during the term. Subject to
the foregoing, the Administrator in its sole discretion shall specify the term,
interest rate and other provisions of the note. The Administrator may require
that the offeree or optionee pledge his Shares to the Company for the purpose of
securing payment for the note, and the Administrator may require that the
certificate(s) representing such Shares be held by the Company as a security
holder in order to perfect the Company's security interest.

     7.3  Withholding.
          -----------

          (a)  Generally.  Notwithstanding the provisions of Sections 7.1 and 
               ---------
7.2 hereof, whenever under any agreement evidencing options, shares or any 
monetary amount are issued to any grantee, the Company shall be entitled to 
require as a condition of delivery that the grantee agree to remit, at the time 
of such delivery or at such later date as the Company may determine, an amount 
sufficient to satisfy all federal, state and local withholding tax requirements 
relating thereto.

          (b)  Withholding of Shares.  With the consent of the Administrator, 
               ---------------------
and in accordance with any rules and procedures from time to time adopted by the
Administrator, a grantee may elect to satisfy by (i) directing the Company to
withhold a portion of the Shares otherwise deliverable or (ii) tendering to the
Company other Shares which are already owned by such grantee or purchaser,
which, in all cases, have a Fair Market Value on the date as of which the amount
of tax to be withhold is determined (the "Tax Date") equal to the amount of tax
to be paid with respect to such Shares.

          (c)  Form of Election.  Any election made pursuant to Paragraph 7.3(b)
               ----------------
above must:

               (i)   be made in writing on or prior to the Tax Date and specify
whether all or a stated percentage of the applicable taxes will be paid with
Shares and whether the amounts so paid shall be made in accordance with the
"flat" withholding rates for supplemental wages or as determined in accordance
with the grantee's Form W-4 (or comparable state or local forms);

               (ii)  be irrevocable once made; and

               (iii) conform in all respects to all rules and procedures from 
time to time adopted by the Administrator and be subject to rejection by the 
Administrator for any reason.

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8.   TERM OF THE PLAN.

     Unless sooner terminated by the Board in its sole discretion, the Plan 
shall expire on June 16, 2003.

9.   AMENDMENTS TO THE PLAN.

     The Plan may be amended from time to time by the Board; provided that any 
                                                             --------
amendment which (a) increases the number of Shares which may be issued under the
Plan, (b) materially increases the benefits accruing to persons eligible to 
purchase Shares under the Plan or (c) materially modifies the requirements for 
eligibility for purchasing Shares under the Plan, shall not become effective 
unless and until approved by the shareholders of the Company.

     The Company intends that the Plan shall comply with the requirements of 
Section 422 of the Code with respect to incentive stock options issued under the
Plan. Should any provisions of the Plan not be necessary to comply with the Code
requirements or should any additional provisions be necessary for the Plan to 
comply with the Code requirements, the Board may amend the Plan to add or modify
the provisions of the Plan accordingly without the necessity of shareholder 
approval.

10.  EFFECTIVE DATE; SHAREHOLDER APPROVAL.

     This Plan shall be effective as of the date it has been adopted by the 
Board of Directors of the Company; however, no Shares may be sold under the Plan
unless and until shareholder approval of the Plan shall have been obtained. 
Options may be granted prior to obtaining shareholder approval; provided that 
                                                                --------
each option agreement shall provide that the option may not be exercised unless 
such approval is obtained prior to June 16, 1994.

11.  ASSUMPTION.

     The terms and conditions of any outstanding options granted pursuant to 
this Plan shall be assumed by, be binding upon and inure to the benefit of any 
successor corporation to the Company and shall continue to be governed by, to 
the extent applicable, the terms and conditions of the Plan.

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