Effect of Drying Method on Functional Properties of Yam (Dioscorea Sp.) Flour

Abstract

The effect of drying method on functional properties of five different yam flour varieties namely, white yam, purple yam, yellow yam, water yam and three leaves yam were studied using oven, solar and sun drying method. The functional properties were determined using AACC approved method. Results revealed that White yam recorded wettability range of 173.22 – 181.31 secs while the purple yam had wettability range from 151.69 to 201 secs, the three leave Yam, had wettability range from 138.41 to 190.20 secs, the water yam and yellow yam recorded wettability range from 143.62 to 182.11 secs and 153.42 to 174.34 secs respectively. Result also indicated that white yam recorded water absorption capacity (WAC) range from134.32 to 146.11, while purple yam had WAC range from 134.32 to 145.46; three leave Yam, water yam and yellow yam recorded from 129.56 to 138.11, from 133.58 to 163.21 and from 128.34 to 143.88 respectively. Furthermore, white yam, purple yam, three leave yam, water yam and yellow yam respectively recorded swelling power range from 11.84 to 12.63, from 11.14 to 11.82, from 11.28 to 12.66, from 12.19 to 12.38 and from 11.68 to 11.96. The three leave yam recorded the highest water absorption capacity which makes it likely to have least shelf life stability as compared to others because of the ability of absorbing water from a humid atmosphere. Results of the analysis of variance (ANOVA) on the effect of drying methods on the functional properties of the yam varieties showed significant difference at 5% and 1% probability level while the yam varieties did not show any significant different on the functional properties of the yam flour varieties.

Uticaj metode sušenja na funkcionalna svojstva pet različitih tipova brašna od Jam (Yam): belog, ljubičastog , žutog, vodenog i tri lišća, proučavan je metodom sušenja u peći i na suncu. Funkcionalna svojstva su određena metodom odobrenom od AACC. Rezultati ispitivanja su pokazali da je Beli tip Jam (Yam) ima opseg vlažnosti (WAC) od 173.22 do 181.31 secs, dok je ljubičasti varijetet Jam (Yam) imao opseg vlažnosti od: 151.69 do 201 secs. Tri preostala varijeteta jama, imali su respektivno raspon vlažnosti: 138.41 do 190.20 secs, a vodeni i žuti jam imaju zabeležen opseg vlažnosti od 143.62 do 182.11 secs i od 153.42 do 174.34 secs. Rezultat istraživanja je takođe pokazao da beli Jam (Yam) beleži kapacitet upijanja vode (bubrenje) (VAC) u opsegu od 134.32 do 146.11 secs, dok je ljubičasti Jam (Yam) imao VAC opseg od 134.32 do 145.46. Napušteni varijeteti ove kulture: vodeni i žuti Jam (Yam) imale su vrednosti: 129.56 do 138.11; 133.58 do 163.21, i 128.34 do 143.88 secs. Pored toga, beli jam, purpurni jam, žuti jam su zabeležili respektivno raspon vlage bubrenja od: 11.84 do12.63; 11.14 do 11.82; 11.28 do 12.66; 12.19 do 12.38 i od 11.68 do 11.96. Tri tipa brašna od Jam (Yam) kulture ostvarila su najveću sposobnost apsorpcije vode, zbog čega je verovatno da će imati najmanju stabilnost u odnosu na druge zbog sposobnosti apsorpcije vode iz vlažne atmosfere. Rezultati analize varijanse (ANOVA) o uticaju metoda sušenja na funkcionalna svojstva različitih varijeteta kulture Jam (Yam) pokazali su značajnu razliku na nivou verovatnoće od 5% i 1%, dok varijeteti kulture Jam (Yam) nisu pokazale značajne razlike u funkcionalnim svojstvima varijeteta brašna.