Effect of Enzymatic Hydrolysis on Solubility, Hydrophobicity, and In Vivo Digestibility in Cowpea (Vigna unguiculata)

Figures & data

Table 1 Composition (%) of experimental diets containing casein (C), Alcalase^® hydrolysate (AH), or Flavourzyme^® hydrolysate (FM) as a protein source

	Diets (g/100 g)
Ingredients	C	AH^c	FH^c
Protein source	10	15.6	15.6
Glucose	15	15	15
Corn starch	66.9	61.2	61.2
Corn oil	5	5	5
Cellulose	2	2	2
Vitamin mix^a	0.5	0.5	0.5
Mineral mix^b	0.6	0.6	0.6
Determined composition (%)
Protein (N × 6.25)	10	10	10
Fiber	2	2	2
Fat	5	5	5
Contents (g/kg diet): nicotinic acid, 3.0; calcium pantothenate, 1.6; pyridoxine HCL, 0.7; thiamin HCl, 0.6; riboflavin, 0.6; folic acid, 0.2; D-biotin, 0.02; vitamin B12 (0.1% in mannitol), 2.5; DL-alpha tocopheryl acetate (500 IU/g), 15.0; dry vitamin A palmitate (500,000 IU/g), 0.8; vitamin D3 (cholecalciferol, 500,000 IU/g), 0.2; vitamin K (phylloquinone), 0.075; sucrose, finely ground, 974.705.
Calcium carbonate, 357.0; potassium phosphate, monobasic (KH2PO4), 196.0; potassium citrate, monohydrate 70.78; sodium chloride (NaCl), 74.0; potassium sulfate (K2SO4), 46.6; magnesium oxide (MgO), 24.3; ferric citrate, 6.06; zinc carbonate, 1.65; manganous carbonate, 0.63; cupric carbonate, 0.31; potassium iodate (KIO3), 0.01; sodium selenate (Na2SeO4), 0.01025; ammonium paramolybdate ((NH4)6Mo7O24.^4H2O), 0.00795; sodium meta-silicate (Na2SiO3.^9H2O), 1.45; chromium potassium sulfate (CrK(SO4)^2.^12H2O), 0.275; lithium chloride (LiCl), 0.0174; boric acid (H3BO3), 0.0815; sodium flouride (NaF), 0.0635; nickel carbonate, hydroxide, tetrahydrate, 0.0318; ammonium vanadate (NH4VO3), 0.0066; sucrose, finely ground, 220.716.
AH and FH protein percentage = 64%.

Figure 1 Changes in degree of hydrolysis (%) over time of V. unguiculata protein concentrates treated with Alcalase^® and Flavourzyme^®. ^a–dDifferent letters in the same reaction time and in the same enzyme indicate statistical difference (P < 0.05).

Figure 2 Nitrogen solubility of V. unguiculata protein concentrate and hydrolysates generated with Alcalase^® and Flavourzyme^®. ^a–cDifferent letters in the same pH value indicate statistical difference (P < 0.05).

Figure 3 SDS-PAGE pattern of V. unguiculata protein concentrate and hydrolysates after treatment with Alcalase® or Flavourzyme^®. ST = Standard; VPC = V. unguiculata protein concentrate; AH = Alcalase^® hydrolysate; FH = Flavourzyme^® hydrolysate. (Color figure available online.)

Table 2 Ingested and excreted nitrogen and apparent digestibility in diets containing V. unguiculata protein hydrolysates produced with Alcalase^® or Flavourzyme^® and a control diet containing casein

	Ingested N2 (g/100 g)	Excreted N2 (g/100 g)	Apparent digestibility (%)
AH	8.22 ± 0.77^a	0.02 ± 0.01^a	99.79 ± 0.10^a
FH	9.62 ± 0.74^b	0.02 ± 0.01^a	99.78 ± 0.09^a
C	8.66 ± 0.78^b	0.01 ± 0.01^a	99.87 ± 0.06^a
AH: Diet containing Alcalase® hydrolysate; FH: Diet containing Flavourzyme® hydrolysate; C: Control diet containing casein. *Different letters in the same column indicate statistical difference (P < 0.05).