Efficacy of various techniques on biochemical characteristics and bitterness of pummelo juice

Abstract

The consumer acceptability of pummelo juice is affected badly due to the presence of bitter principles in it. Therefore in order to avoid such bitterness development, the extracted juice from pummelo was subjected to five different treatments like juice diffused into syrup (70°Brix), lye peeling of segments in boiling NaOH for 2-3 min, increasing the pH of juice, hot water treatment (50°C) prior to peeling for 20 min and without any treatment (control) for suppressing the development of bitterness in the juice. Based on biochemical analysis, diffusion of juice into syrup (70°Brix) showed better result as compared to other treatments. The maximum amount of TSS was found in juice diffused into syrup (i. e. 45, 30 and 15°Brix) along with highest TSS/acid ratio (92.21, 49.87 and 17.53). Higher amount of acidity was observed in pH adjusted samples with 4.25, 4.50 and 4.75 respectively. However, control samples showed higher amount of ascorbic acid (73.97 mg/100 ml juice) content followed by pH adjusted samples. The highest organoleptic score for taste (8.00), colour (8.83), aroma (8.66), overall acceptability (7.88) and extent of debittering (7.50) were recorded in juice diffused into syrup 70°Brix and achieved final TSS of juice at 45, 30 and 15°Brix respectively. Moreover, the above treatment (juice diffused into syrup 70°Brix) showed promising low cost and easy to adopt technique of debittering in respect of extent of debittering and maintaining sensory quality during storage of pummel juice.

Citrus Taste Modification Potentials by Genetic Engineering

“…Limonoid is the other major type of bitter compound in addition to naringin in citrus fruit, including nomilin and limonin [8,24]. A study has shown that generally limonoids accumulate relatively high at young fruit or fruit expanding stage and then fall to very low in concentration or under detectable levels in mature fruit [36].…”

“…Although flavor is favored differently for different individuals, there is a generally accepted notion of good taste which is attributed to an appropriate balance of sweetness and sourness in citrus [7]. Excessive bitterness and the delayed bitterness in citrus pose great challenge for the citrus industry to provide consumers readily acceptable fresh fruit and citrus juice, thus causing great lose in citrus market value [8]. Extremely sour and acidic can destroy the sweet taste of citrus and may be physiologically harmful to humans.…”

Phytochemical and Therapeutic Potential of Citrus grandis (L.) Osbeck: A Review

“… 47 Furthermore, the fruit juice prepared from the pulp is rich in antioxidant and polyphenolic compounds such ferulic acid, hesperidin, caffeic acid, naringin, p-coumaric acid, and vanillic acid were reported to be present in the fruit juice. 33 , 44 , 48 – 51 Current chemical, medical, and pharmacological literature has confirmed various pharmacological activities as well as nutritional value of the indigenous fruit and so a compendious review of the plant is established.…”

Isolation and characterization of naringinase enzyme and its application in debittering of Pomelo juice ( Citrus grandis ): A comparative study with macroporous resin

“…The pomelo juice has the prime bittering component, such as naringin, narirutin, neoeriocitrin, eriocitrin, neohesperidin, and hesperidin, with a level of 245.63-393.96 mg/L which are not desirable in fruit processing industries as they reduce the consumer acceptability (Pichaiyongvongdee & Haruenkit, 2009). Processing techniques like blanching (Zid et al, 2015), application of adsorptive materials, for example, cellulose triacetate (Chandler & Johnson, 1977) and cellulose esters (Barmore et al, 1986), chemical methods with the use of β-cyclodextrin (Konno et al, 1981), resins (Gupta et al, 2020;Kola et al, 2010;Mishra & Kar, 2003;Singh et al, 2016), mixed with sugar syrup (Kore & Chakraborty, 2015), lye peeling (Kore & Chakraborty, 2015), pH adjustment (Kore & Chakraborty, 2015), hot water treatment (Kore & Chakraborty, 2015), and the combination of sucrose and citric acid (Guadagni et al, 1974) were employed for debittering. Polystyrene divinylbenzene, resin (Mishra & Kar, 2003), poly (vinyl alcohol) (PVA), and cryogel (Busto et al, 2007) were also used successfully for the removal of bitterness from the juices; however, the physical and chemical methods are not always welcomed by the juice processing industries, as these techniques had several drawbacks including loss of chemical components like acidity, vitamin C, and soluble solids.…”