A Review of Nigerian Potential Hop Substitutes in Beer Brewing: 1983-2020

The Nigerian economy depended mainly on crude oil during the era of oil boom of 1973 which lasted up till1983. Agriculture was grossly neglected by successive governments. Following the economic recession that occurred years after and due to fall in crude oil price, the Nigerian government began to advocate for economic diversification. Consequently, agriculture became the area of interest and priority for industrial raw material sources. Unfortunately, Nigeria had imbibed the tradition of importing raw materials for all her industrial productions thereby creating unfavourable balance of trade between Nigeria and her foreign trading partners thus resulting in increase in the prices of finished products. Beer production is not exempted from the price increase since its raw materials are equally imported with their attendant problems on Nigeria’s foreign exchange. One of such raw materials is hops. The hop (Humulus lupulus L.) is a perennial dioecious climbing plant of hemp (cannabis) family and belonging to the order (urticales) which are grown in the temperate regions of the world, solely to meet the demand of the brewing industry. Hop extracts give beer its bitter taste, improve foam stability and act as antiseptics towards microorganisms. The quest to substitute hops with some tropical bitter vegetables in Nigeria’s brewing industry dates back to 1983 and since that time, many have compared hop extracts with those of Nigerian bitter plants such as Garcinia kola, Azadirachta indica, Vernonia amygdalina and Gongronema latifolium. This review takes a critical look on the efforts made so far since 1983 in investigating the potentiality of using Nigerian bitter plant extracts as suitable substitute for those of hop in the Nigerian brewing industry with special emphasis on Gas Chromatography Mass–Spectrometry (GC–MS) and Gas Chromatography–Flame Ionization Detector (GC–FID) techniques. It was concluded that none of the Nigerian plants has perfect potential as suitable substitute for hops in the Nigerian brewing industry. Consequently, further research efforts in the area of mixtures/blends of extract of plant species which mimic hop taste is strongly recommended.