From Seed to Food: Quality, Processing and Safety of Hemp Seed and Press Cake Ingredients for Food Applications

Hemp (Cannabis sativa L.) seed and the press cake obtained after oil extraction are gaining importance as sources of plant protein, dietary fiber and polyunsaturated lipids, while the cake remains a largely underused by-product. Their use in food is, however, limited by variable composition, low protein solubility, modest sensory acceptance and regulatory uncertainty. Whole seed of commercial cultivars generally contained 17–29% protein and 21–36% oil; lysine remained the limiting amino acid, while linoleic and α-linolenic acids accounted for most of the fatty acids. Dehulling, pressing conditions, and residual oil generally affected functionality more than the cultivar, although not for all endpoints. Ultrasound-assisted and salt-based extraction gave the most consistent laboratory-scale gains in protein recovery and solubility, whereas fermentation and enzymatic hydrolysis increased in vitro bioactivity but have not been validated at food scale. In cereal, dairy-type, and meat products, hemp ingredients increased protein and fiber contents, while color, bitterness, and lipid oxidation limited acceptable wheat flour replacement to about 5–15% in most formulations studied. Compliance with the EU maximum levels for Δ9-THC equivalents required determining both THC and THCA in each lot. This review evaluated how composition, processing and safety requirements determine the quality of hemp seed and press cake ingredients.