beverages Article Coconut Neera—A Vital Health Beverage from Coconut Palms: Harvesting, Processing and Quality Analysis Mohankumar Chinnamma *, Salini Bhasker, Malavika Binitha Hari, Divyaa Sreekumar and Harish Madhav Molecular Biology Division, SCMS Institute of Bioscience and Biotechnology Research and Development (SIBBR&D), Management House, South Kalamassery, Cochin 682033, Kerala, India; [email protected] (S.B.); [email protected] (M.B.H.); [email protected] (D.S.); [email protected] (H.M.) * Correspondence: [email protected]; Tel.: +91-484-255-6315 Received: 12 January 2019; Accepted: 30 January 2019; Published: 2 March 2019 Abstract: Nature has made nutritive products in such a way that it cannot be manufactured in laboratories or in mills. Coconut Neera is the natural sap of the mature coconut palms rich with all essential nutrients, minerals and vitamins for human health. Harvesting of Neera from the spadix of the palms without disturbing the physiology of the tree has a lot of potential at the industrial scale. However, the development of alcohol in the extracted sap during tapping by auto-fermentation has given a misnomer for Neera as “sweet toddy”. Hence, the commercial popularity of Neera as a health drink has diminished at a global level. Though several traditional techniques like the usage of calcium hydroxide (lime) and the application of the chiller device during harvesting Neera from spadix have been practiced for collecting non-fermented Neera, none of the techniques were found acceptable at the commercial level. The results of the present study demonstrate the harvesting and processing procedure standardized for the collection and storage of non-fermented Neera from palms by repeated field trials. The cumulative effect of the anti-fermentation solution (AFS) with the presence of the two preservatives—citric acid (5 mM) and potassium metabisulphite (2 mM)—by preventing fermentation from the level of harvesting to processing was confirmed. The zero content of alcohol in raw Neera indicates the AFS action. The proximate composition of primary constituents and the content of minerals, amino acids and vitamins present in Neera highlights its nutrient value as a health beverage. The higher content of minerals—sodium and potassium (15.2 mg and 100 mg), the elevated level of amino acids-cysteine (14 mg), tyrosine (7.11 mg), arginine (7 mg) and the presence of vitamin C (65 mg) and vitamin A as retinol (4.88 IU)—indicates the therapeutic importance of coconut Neera. The data of oral toxicity and the glycemic index further support the vital quality. Keywords: Cocos nucifera; coconut palms; coconut Neera; anti-fermentation solution; harvesting and processing; Neera sugar; Neera concentrate 1. Introduction Coconut has been in existence for millions of years in almost all tropical countries, and the people of the tropical world use a eulogistic epithet “Tree of Life” for coconut palms. This is because whatever is needed for one’s livelihood—food, fuel, medicine and shelter—is available from this wonder palm. Coconut palm has been studied mostly from the commercial angle, as it is the source of edible oil, food, coconut water, coconut milk, fibre, wood and fuel. Because of the diversified food value, the potential of coconut can be exploited from the flowering phase to the mature nut [1]. At the reproductive phase, a coconut tree develops bunches of male and female flowers that are kept inside in a protective coat Beverages 2019, 5, 22; doi:10.3390/beverages5010022 www.mdpi.com/journal/beverages Beverages 2019, 5, x FOR PEER REVIEW 2 of 15 value, the potential of coconut can be exploited from the flowering phase to the mature nut [1]. At the reproductive phase, a coconut tree develops bunches of male and female flowers that are kept inside in a protective coat safely, called spadix, until it blossoms for reproduction (Figure 1). The Beverages 2019 5 sweet sap of unblossomed, , 22 mature spadix of coconut trees has been used as a natural2 of 14 drink for decades, but its marketing stability at the commercial scale is not at all competent due to the safely, called spadix, until it blossoms for reproduction (Figure1). The sweet sap of unblossomed fermented naturemature of spadix the drink, of coconut leading trees has to been the used formation as a natural of drink alcohol. for decades, Technically, but its marketing the sweet stability sap oozed out during tappingat the commercial from the scale spadix is not athas all competenttwo nutritional due to the status: fermented (i) nature Fermented of the drink, sap leading with to5– the8% alcohol called sweet toddyformation and of (ii) alcohol. non Technically,-fermented the sap sweet named sap oozed Neera out during with tappingzero alcohol. from the Though spadix has both two the saps have vital nutrients,nutritional the status: presence (i) Fermented of alcohol sap with in 5–8% sweet alcohol toddy called remains sweet toddy as a and hurdle (ii) non-fermented for popularizing sap it as named Neera with zero alcohol. Though both the saps have vital nutrients, the presence of alcohol a natural soft indrink. sweet toddyThe major remains concern as a hurdle of for the popularizing Neera industry it as a natural is to soft maintain drink. The majorthe nutritional concern of quality with zero alcoholthe Neera since industry Neera is has to maintain an innate the nutritional tendency quality of auto with- zerofermentation. alcohol since NeeraHence, has the an innate harvesting of Neera withouttendency auto-fermentation of auto-fermentation. remains Hence, as the a harvesting challenge of Neera before without the auto-fermentation Neera industry. remains Despite the as a challenge before the Neera industry. Despite the traditional approach of tapping, a scientific traditional approachapproach forof harvesting tapping, and a processing scientific Neera approach by maintaining for itsharvesting nutritional andand therapeutic processing value atNeera by maintaining itsthe nutritional industrial scale and has therapeutic not been done properly.value at the industrial scale has not been done properly. Figure 1. TheFigure u 1.nbloThes unblossomedsomed spadix spadix of of a a mature mature coconut coconut palm. palm. Generally, the tapping procedure followed for Neera production is precisely a repetition of the Generally,traditional the tapping toddy extraction,procedure and followed this may be for the Neera possible production reason that Neera is precisely has got the a misnomer repetition of the traditional toddy“sweet extraction toddy” [2,3,]. and Therefore, this may the major be threatthe possible in the harvesting reason process that Neera of Neera has from got the spadixthe misnomer “sweet toddy”of [2,3]. coconut Therefore palm is the, naturalthe major fermentation threat orin auto the fermentation harvesting of proces the sap.s Being of Neera a natural from sugary the spadix solution extracted from the plant tissue, it has an innate tendency of getting fermented and it can of coconut palmhappen is the by twonatural means: fermentation auto-fermentation or ofauto the sapfermentation and unhygienic of harvesting the sap. and Being storage. a natural Fresh sugary solution extractedcoconut from sap (Neera) the plant at the tissue, time of harvestit has isan sweet innate in taste tendency with all the of vital getting nutrients fermented of an energy and it can happen by twohealth means: drink. auto However,-fermentation the innate association of the ofsap micro-organisms and unhygienic like yeast harvesting and bacteria and in the storage. sweet Fresh sap activates fermentation, resulting in the production of ethyl alcohol [4]. Therefore, the present coconut sap (Neera)investigation at the was time undertaken of harvest with the aimis sweet to produce in taste non-fermented with all Neera the fromvital coconut nutrients palms withof an energy health drink. theHowever, following objectives:the innate to develop association an exclusive of micro harvesting-organisms procedure forlike Neera yeast by preventingand bacteri the a in the sweet sap activatesin situ fermentation fermentation at the, fieldresulting itself, to designin the a processingproduction protocol of forethyl the harvestedalcohol Neera[4]. Therefore with a , the stable shelf life at room temperature and to analyze the nutritional quality of the processed Neera for present investigation was undertaken with the aim to produce non-fermented Neera from coconut determining its vital nature as a health beverage. palms with the following objectives: to develop an exclusive harvesting procedure for Neera by preventing the2. Materialsin situ andfermentation Methods at the field itself, to design a processing protocol for the harvested Neera withThe methodology a stable shelf part life of the at investigationroom temperature was carried and out to under analyze four phases: the nutritional tapping and quality of harvesting; processing and storing the harvested Neera; conducting a nutritional analysis; preparing the processed theNeera value-added for determining products from its Neera. vital nature as a health beverage. 2. Materials and Methods The methodology part of the investigation was carried out under four phases: tapping and harvesting; processing and storing the harvested Neera; conducting a nutritional analysis; preparing the value-added products from Neera. 2.1. Tapping and Harvesting A scientific approach was maintained for the harvesting by following modifications in the traditional tapping practiced by the toddy tappers (Figure 2): (i) The selection of healthy palms: As the first step of tapping, 250 healthy coconut palms (Cocos nucifera) of approximate 25–30 m with mature unblossomed spadix were selected for the study. The height of the tree, number of mature Beverages 2019, 5, 22 3 of 14 2.1. Tapping and Harvesting A scientific approach was maintained for the harvesting by following modifications in the traditional tapping practiced by the toddy tappers (Figure2): (i) The selection of healthy palms: As the first step of tapping, 250 healthy coconut palms (Cocos nucifera) of approximate 25–30 m with mature unblossomed spadix were selected for the study.