Yam Tuber Dormancy and Sprouting: The Role of Concentration Dynamics of Endogenous Gibberellic Acid

The role of endogenous gibberellic acid (GA ) in the regulation of yam (Dioscorea spp.) tuber 3 dormancy was investigated by determining the changes in the endogenous GA levels during 3 natural dormancy progression. Two Dioscorea rotundata cultivars ('Pona' and 'Labreko') and one Dioscorea alata cultivar ('CRI-Ahoɔdenfoɔ') used in these studies have varying dormancy duration. Endogenous GA levels determined for the yam tubers ranged from 1.53 – 3.05 mg/g dw 3 and 1.23 – 1.58 mg/g dw for 'Pona'; 1.53 – 3.40 mg/g dw and 1.25–1.57 mg/g dw for 'Labreko'; 1.48 – 3.62 mg/g dw and 1.28 – 1.60 mg/g dw for 'CRI-Ahoɔdenfoɔ', respectively, for the outer and inner portions. 'Pona' and 'Labreko' had dormancy break at 60 days after harvest (DAH), but at 90 DAH for 'CRI-Ahoɔdenfoɔ'. Generally, GA levels increased from harvest to the maximum 3 at 30 DAH, then declined to the minimum at 60 DAH before finally increasing again at 90 DAH for the outer portions of the yam tuber. For the inner portions of the tuber, GA levels rather 3 declined significantly to the minimum at 30 DAH, increased at 60 DAH and then decreased again at 90 DAH. GA levels in the outer portions of the tubers increased by 84-122%, 65-77% and 61- 3 65%, respectively, in 'CRI-Ahoɔdenfoɔ', 'Labreko' and 'Pona', but decreased in the inner portions by 19-23%, 24-26% and 26-28%. Essentially, higher amounts of endogenous gibberellins in yam tubers induced longer dormancy duration whereas lower amounts were indicative of dormancy termination and subsequent initiation of sprouting.&nbsp

Spectroscopy as a rapid detecting paprika powder adulteration

Paprika powder, a spice known for imparting flavour, colour and aroma in foods has recently become compromised by fraudulent activities involving diverse adulterants such as corn flour and has prompted quality assurance (QA) measures. Near infrared spectroscopy (NIRS) is a non-destructive method gaining grounds in QA applications. The study applied NIRS to detect paprika powder adulterated with corn flour. Chemometric evaluation spectra showed that NIRS could discriminate cornflour adulteration with 100% classification accuracy. Adulteration was also predicted with high accuracies coefficient of determination (R2CV) between 0.97 and 0.99 and low errors (0.72 g/100g), proving the future QA applications of NIRS

Influence of storage conditions and packaging materials on some quality attributes of water yam flour

The study investigated some quality attributes of water yam flour stored in three packaging materials [high and low density polyethylene and plastic container] under different storage conditions [relative humidity (36%, 56%, 75% and 96%), temperature (25±2, 35±2 and 45±2 °C)] for 24 weeks. The functional properties, proximate composition and microbial load of the samples were evaluated at 4 weeks interval. Significant differences (p<0.01) were observed for proximate composition, functional properties and microbial load of the samples during storage. The interactive effect of storage conditions and packaging materials was significant (p<0.01) on proximate composition and pasting properties (except trough viscosity). The yam flour samples were still shelf stable after the 24 weeks of storage