A marketing order may contain provisions which establish, or provide for the establishment, with respect to any commodity, either as delivered by producers to handlers or processors, or as handled, processed, or otherwise prepared for market, or as marketed by producers, handlers, or processors, both of the following:
(a) Grading standards of quality, condition, size, maturity, or pack, which standards may include minimum standards. The standards so established shall not, however, be established below any minimum standards which are prescribed by law for such commodity.
(b) Uniform inspection and grading of such commodity in accordance with the standards which are so established.