The Effects of Processing on Bioactive Compounds and Biological Activities of Sorghum Grains

Abstract

Sorghum is ranked the fifth most commonly used cereal and is rich in many kinds of bioactive compounds. Food processing can affect the accumulation and decomposition of bioactive compounds in sorghum grains, and then change the biological activities of sorghum grains. The present review aims to analyze the effects of processing technologies on bioactive compounds and the biological activities of sorghum grains. Decortication reduces the total phenols, tannins, and antioxidant activity of sorghum grains. The effects of thermal processes on bioactive compounds and potential biological activities of sorghum grains are complicated due to thermal treatment method and thermal treatment conditions, such as extrusion cooking, which has different effects on the bioactive compounds and antioxidant capacity of sorghum due to extrusion conditions, such as temperature and moisture, and food matrices, such as whole grain and bran. Emerging thermal processes, such as microwave heating and high-pressure processing, could promote the release of bound phenolic substances and procyanidins, and are recommended. Biological processes can increase the nutritive and nutraceutical quality and reduce antinutritional compounds, except for soaking which reduces water-soluble compounds in sorghum.

Advances in the novel and green-assisted techniques for extraction of bioactive compounds from millets: A comprehensive review

“…The concentrations of various bioactive compounds in different varieties of millets are summarized in Table 1 . For instance, sorghum grain's phenolic acids include caffeic acid, p-coumaric acid, ferulic acid, sinapic acid, chlorogenic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, salicylic acid, gallic acid, and syringic acid [ 48 ]. Flavonoids are abundant in the outer layers, which include anthocyanins, dihydro flavanol, flavones, flavanones, flavanols, flavanols, and isoflavones, with anthocyanin s being the predominant compound [ 48 ].…”

“…For instance, sorghum grain's phenolic acids include caffeic acid, p-coumaric acid, ferulic acid, sinapic acid, chlorogenic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, salicylic acid, gallic acid, and syringic acid [ 48 ]. Flavonoids are abundant in the outer layers, which include anthocyanins, dihydro flavanol, flavones, flavanones, flavanols, flavanols, and isoflavones, with anthocyanin s being the predominant compound [ 48 ]. Sorghum grains contain varying amounts of xanthophylls such as lutein and zeaxanthin, with lutein, zeaxanthin, and β-carotene being the most frequently found [ 49 ].…”

Implications of husking process on the nutritional composition of sorghum grains: diverse varieties and regions

“…Despite to process advantages, the most common traditional technique of processing sorghum grain consumes time. For instance, a recent paper on sorghum germination indicated that nutritional improvements were seen after 7 days of the procedure (Kayisoglu et al ., 2024), confirming, to literature as outlined sorghum processing issues addressing the inefficiency of germ removal and time‐consuming, which can leads to decreased shelf life and discolouration, ultimately affecting the quality and appearance of the final product (Li et al ., 2022; Khoddami et al ., 2023), Hence, it is necessary to involve more effective time processing, as the HFTU procedure provides. Furthermore, the modern grain processing equipment prioritises environmental protection requirements and operational safety, ensuring a people‐centric and sustainable approach (Lovegrove et al ., 2023).…”

Effect of combined germination and spontaneous fermentation on the bioactive, mineral, and microbial profile of red sorghum and pearl millet flours

“…Soaking, which is a preliminary step to mechanical and biological processing of cereals, can lead to the modifications of grains texture and the release of water-soluble compounds. Many studies showed soaking significantly decreased total phenols and minerals, while others revealed an increase in antioxidant activity (Li et al, 2022). Germination results in the degradation of macronutrients, reduction of anti-nutritional factors, and increase of the bioactive potential of sorghum grains (Liu et al, 2019).…”

“…Germination results in the degradation of macronutrients, reduction of anti-nutritional factors, and increase of the bioactive potential of sorghum grains (Liu et al, 2019). Studies on fermentation revealed contradictory effects on total phenol contents and total flavonoid contents (Li et al, 2022). A review done by Taylor and Duodu (2015) showed that biological processing methods also affect the antioxidant potential of sorghum and millet grains.…”