Note 11 - Business Segment Reporting (Details) - Operations by Business Segment (USD $)	3 Months Ended
	Aug. 31, 2014	Aug. 25, 2013
Segment Reporting Information [Line Items]
Net sales	$ 133,614,000	$ 109,479,000
International sales	46,372,000	35,244,000
Gross profit	14,188,000	12,532,000
Net income (loss)	2,353,000	4,752,000
Depreciation and amortization	1,513,000	1,842,000
Dividend Income	281,000	281,000
Interest income	93,000	60,000
Interest expense	383,000	431,000
Income tax expense	1,301,000	2,475,000
Food Products Technology [Member]
Segment Reporting Information [Line Items]
Net sales	100,106,000	79,436,000
International sales	18,151,000	9,478,000
Gross profit	11,854,000	8,881,000
Net income (loss)	3,646,000	7,266,000
Depreciation and amortization	1,010,000	1,222,000
Dividend Income	281,000	281,000
Interest income	11,000	4,000
Interest expense	338,000	376,000
Income tax expense	870,000	505,000
Food Export [Member]
Segment Reporting Information [Line Items]
Net sales	26,597,000	21,398,000
International sales	26,587,000	21,389,000
Gross profit	1,186,000	1,205,000
Net income (loss)	271,000	276,000
Depreciation and amortization	1,000	1,000
Income tax expense	44,000	78,000
HA-based Biomaterials [Member]
Segment Reporting Information [Line Items]
Net sales	6,811,000	8,587,000
International sales	1,634,000	4,377,000
Gross profit	1,048,000	2,388,000
Net income (loss)	(1,542,000)	(376,000)
Depreciation and amortization	471,000	584,000
Interest income	71,000	56,000
Interest expense	45,000	55,000
Income tax expense	(251,000)	(106,000)
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Net sales	100,000	58,000
Gross profit	100,000	58,000
Net income (loss)	(22,000)	(2,414,000)
Depreciation and amortization	31,000	35,000
Interest income	11,000
Income tax expense	$ 638,000	$ 1,998,000