Schedule of Property, Plant and Equipment (Details) - USD ($)	Feb. 28, 2022	May 31, 2021
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 65,265,847	$ 61,301,417
Less: Accumulated depreciation and amortization	(33,166,171)	(30,302,429)
Net Property, Plant and Equipment	32,099,676	30,998,988
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	56,215,850	52,292,733
Plant Buildings and Land [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	7,020,542	6,970,949
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	1,487,398	1,487,398
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 542,057	$ 550,337

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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