Kenaf (Hibiscus cannabinusL.) Seed Extract as a New Plant-Based Milk Alternative and Its Potential Food Uses

Abstract

Kenaf (Hibiscus cannabinus L.) seed is rich in protein, fat, fiber, and other essential nutrients. Kenaf seed comprises of high protein (22–31%) and oil (22–25%) contents which suggested its high potential food application. This chapter discusses the potential and early development of kenaf-based plant-milk and tofu. The step-by-step processes involved in preparation of kenaf-based milk and kenaf-based tofu at laboratory-scale are illustrated. Soaking conditions (temperature and time) of kenaf seed as pretreatment in preparation of kenaf seed milk were highlighted. Hydration of kenaf seed were found to be faster at elevated temperature, however higher soaking temperature and prolonged soaking time causes some losses of protein (%) and solid content (%) which are unfavorable for production of highly nutritious plant-based milk. Furthermore, in preparation of kenaf-based tofu, soaking temperature of seed also affected the properties of the tofu. As the soaking temperature was increased from 25–65°C, the yield, hardness, and chewiness of kenaf tofu decreased. It was recommended that soaking of kenaf seed at 25°C and the use of aluminum potassium salt at 1.00 g% as coagulant produces kenaf-based tofu with optimum quality.

Utilizing Nutritional and Polyphenolic Compounds in Underutilized Plant Seeds for Health Application

“…In response to the problem, wasted or abandoned kenaf seeds can be reused by being transformed into value-added goods with high-value benefits, including food products. The seeds are edible and can be made more palatable by imparting food additives and seasonings (e.g., sugar, salt, acids, herbs, and spices) to enhance their earthy flavour [ 164 ]. Kenaf seeds have been studied in several animal experimentations and have been found to be non-toxic and safe for consumption [ 165 , 166 ].…”

“…The use of kenaf seed milk extract in food products is receiving considerable attention. Several experiments have been undertaken to generate novel food products from kenaf seed milk extracts, such as tofu made from curdling and kenaf milk beverages with appealing flavours [ 164 , 174 ].…”

Alternative Dietary Fiber Sources from Kenaf (Hibiscus cannabinus L.) Seeds and Their by-Products

“…However, due to their richness in essential nutrients, extensive studies of kenaf seed oil, protein concentrate, and kenaf seed-based food products (i.e. noodles, tofu, milk) have been conducted in recent years (Ibadullah et al 2021;Karim et al 2020;Mariod et al 2017;Monti 2013;Zawawi et al 2014). Defatted kenaf seed meals and kenaf seed dregs are the secondary by-products of kenaf seed oil and milk extractions.…”

Physicochemical and functional properties of carbohydrate–protein gum extracted from kenaf (Hibiscus cannabinus L.) seed

“…Kenaf seeds are one of the major kenaf plant by‐products generally discarded after harvesting (Chan et al ., 2013), as replanting kenaf plants only requires about 2% of the total seed produced (Wei, 2019). Kenaf seeds are high in nutrients such as fat, protein and dietary fibres, hence could serve as potential ingredients for the food industry (Giwa Ibrahim et al ., 2019; Karim et al ., 2020). Therefore, there is a growing research interest in kenaf seed applications such as the production of kenaf seed oil (Chan & Ismail, 2009; Yazan et al ., 2011; Monti, 2013), kenaf seed protein concentrates (Mariod et al ., 2010; Ibrahim et al ., 2021), defatted kenaf seed meals (Chan et al ., 2013), kenaf‐based milk and tofu (Ibrahim et al ., 2020; Karim et al ., 2020).…”

“…Kenaf seeds are high in nutrients such as fat, protein and dietary fibres, hence could serve as potential ingredients for the food industry (Giwa Ibrahim et al ., 2019; Karim et al ., 2020). Therefore, there is a growing research interest in kenaf seed applications such as the production of kenaf seed oil (Chan & Ismail, 2009; Yazan et al ., 2011; Monti, 2013), kenaf seed protein concentrates (Mariod et al ., 2010; Ibrahim et al ., 2021), defatted kenaf seed meals (Chan et al ., 2013), kenaf‐based milk and tofu (Ibrahim et al ., 2020; Karim et al ., 2020). Unfortunately, to the authors’ best knowledge, there is no available information on the kenaf seed gums (KSG), which could be useful for the food industry as a novel low‐cost seed gum source.…”