Pigment Reduction in Corn Gluten Meal and Its Effects on Muscle ...

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y lipoxygenase, compared to destruction rates obta<strong>in</strong>ed when pigments were exposed to LOX orl<strong>in</strong>oleic acid separately.Benzoyl peroxide is widely utilized as a free radical <strong>in</strong>itiator <strong>and</strong> bleach<strong>in</strong>g agent <strong>in</strong><strong>in</strong>dustrial food process<strong>in</strong>g (Gel<strong>in</strong>as et al., 1998). Addition of this compound <strong>in</strong>to the reactionmedia most likely <strong>in</strong>creased pigment bleach<strong>in</strong>g by a typical free radical mechanism act<strong>in</strong>g <strong>in</strong> asynergistic fashion with lipoxygenase <strong>in</strong> this study.The effect of different reaction temperatures (when presoak<strong>in</strong>g time is kept constant at 90m<strong>in</strong>) on pigment bleach<strong>in</strong>g is depicted <strong>in</strong> Figures 3.3 A (20°C), B (15°C) <strong>and</strong> C (10°C).Temperature can modify activity of antioxidants such as ascorbyl palmitate, BHA <strong>and</strong> BHT(Frankel, 2005). LOX catalyzed carotenoid co-oxidation is related to the stability of the radical<strong>in</strong>termediates produced. Less stable <strong>in</strong>termediate species promote higher carotenoid bleach<strong>in</strong>gPerez-Galvez <strong>and</strong> M<strong>in</strong>guez-Mosquera, 2002). Whether or not temperature <strong>in</strong>fluences<strong>in</strong>termediate bleach<strong>in</strong>g species stability is yet to be determ<strong>in</strong>ed, <strong>and</strong> may expla<strong>in</strong> the effect of RTon pigment reduction <strong>in</strong> this study.Carotenoids from CGM (expressed as total yellow pigments, assessed byspectrophotometric method) were reduced by 62% when the optimum factor comb<strong>in</strong>ation wasapplied. Additionally, carotenoid profile (i.e. all-trans lute<strong>in</strong>, all-trans zeaxanth<strong>in</strong>, all-trans β-cryptoxanth<strong>in</strong> <strong>and</strong> all-trans β-carotene) obta<strong>in</strong>ed for CGM (determ<strong>in</strong>ed by liquidchromatography) <strong>in</strong> this study (Table 3.10) is <strong>in</strong> the same range of that reported by Moros et al.2002. All-trans lute<strong>in</strong> <strong>and</strong> all-trans zeaxanth<strong>in</strong> were bleached by about 86% <strong>and</strong> 97%respectively whereas β-cryptoxanth<strong>in</strong> <strong>and</strong> β-carotene were 100% reduced <strong>in</strong> bleached CGM,represent<strong>in</strong>g an overall 91% reduction <strong>in</strong> yellow pigments (as assessed by liquid47
chromatography). Relative amounts of pigments such as flavonoids <strong>and</strong> chlorophyll-likecompounds are determ<strong>in</strong>ed at the same wavelength as xanthophylls <strong>and</strong> carotenes <strong>in</strong> cornsamples (Bless<strong>in</strong>, 1962), the presence of these types of compounds may expla<strong>in</strong> the differencesbetween results expressed as total yellow pigment (determ<strong>in</strong>ed us<strong>in</strong>g spectrophotometry) <strong>and</strong><strong>in</strong>dividual carotenoid (obta<strong>in</strong>ed by liquid chromatography) for regular <strong>and</strong> bleached CGMsamples <strong>in</strong> this study.3.3.2 Fish muscle pigmentation trialGrowth <strong>and</strong> feed utilization parameters obta<strong>in</strong>ed <strong>in</strong> this trial (Table 3.11) are comparableto those commonly observed <strong>in</strong> our laboratory for ra<strong>in</strong>bow trout same stra<strong>in</strong> <strong>and</strong> similar size fedhigh nutritional quality formulated diets (Bureau et al., 2006). No significant (p>0.05)differences were obta<strong>in</strong>ed for ga<strong>in</strong> (g fish -1 ), TGC or feed efficiency which is <strong>in</strong> agreement toprevious reports on CGM <strong>in</strong>clusion <strong>in</strong> salmonids formulated diets (Mundheim et al., 2004;Skonberg et al., 1998)Figure 3.4 depicts growth trajectories over time obta<strong>in</strong>ed <strong>in</strong> this study, even though nostatistically significant, all growth parameters for fish fed Diet 3 showed a reduction tendencydur<strong>in</strong>g the last 50 days of the trial. Additionally, a significant (p
Page 1 and 2:
Pigment Re
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ingredients. Furth
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Thanks to all my colleagues, friend
Page 7 and 8: 2.10.1 Enzymatic treatments .......
Page 9 and 10: LIST OF TABLESTable 3. 1 - Factors
Page 11 and 12: LIST OF FIGURESFigure 2. 1 - Molecu
Page 13 and 14: Ingredients commonly in</st
Page 15 and 16: CHAPTER - 2 LITERATURE REVIEW2.1 In
Page 17 and 18: leached when 5% of soy flour as LOX
Page 19 and 20: deep and fast glyc
Page 21 and 22: observed in ra<str
Page 23 and 24: Chylomicron constituents are remove
Page 25 and 26: Muscle growth in r
Page 27 and 28: 2.7.2 Corn gluten
Page 29 and 30: 2010). However, due to its imbalanc
Page 31 and 32: No differences in
Page 33 and 34: supplemented with 42% of a vegetabl
Page 35 and 36: Soybean seeds are the richest known
Page 37 and 38: 2.10.1.4 Bleaching
Page 39 and 40: 2.11 ConclusionInclusion of <strong
Page 41 and 42: 4.0%*68%* 5.6%* 12%* 3.5%* 6.5%*Fig
Page 43 and 44: Figure 2. 4 - Schematic representat
Page 45 and 46: 3.1 IntroductionThe characteristic
Page 47 and 48: many factors such as LOX source lev
Page 49 and 50: During the 12-week
Page 51 and 52: 3.2.3 Analytical methodsDry matter
Page 53 and 54: solution was generated by mix<stron
Page 55 and 56: 3.2.4 Statistical analysisData from
Page 57: Factors defined as
Page 61 and 62: After carotenoids are absorbed thro
Page 63 and 64: and ended up <stro
Page 65 and 66: Table 3. 2 - Experimental design us
Page 67 and 68: Table 3. 4 - Analysed proximate com
Page 69 and 70: Proximate composition (Analysed; dr
Page 71 and 72: Table 3. 7 - Lipoxygenase activity
Page 73 and 74: 18 1 0 -1 0 120 15 0 10 2519 -1 0 1
Page 75 and 76: Table 3. 10 - HPLC carotenoid profi
Page 77 and 78: Table 3. 12 - Retain</stron
Page 79 and 80: Table 3. 14 - Fillet carotenoid con
Page 81 and 82: Total yellow pigment(mg•kg -1 )25
Page 83 and 84: Figure 3. 4 - Growth curve of ra<st
Page 85 and 86: effects of dietary CGM and<
Page 87 and 88: soybean meal in a
Page 89 and 90: were randomly samp
Page 91 and 92: An aliquot (1 ml) of chloroform low
Page 93 and 94: Retained nitrogen
Page 95 and 96: significant (p
Page 97 and 98: Values for all-trans astaxanth<stro
Page 99 and 100: previous reports where colour attri
Page 101 and 102: Proximate composition (analysed), d
Page 103 and 104: Table 4. 2 - Growth performance of
Page 105 and 106: Table 4. 3 - Carcass chemical proxi
Page 107 and 108: Table 4. 4 - Retain</strong
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Table 4. 5 - Pigment</stron
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Table 4. 6 - Colour attributes <str
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FiguresFigure 4. 1 - Growth curves
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Figure 4. 3 - Muscle colour attribu
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the effects of dietary reduced-caro
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astaxanthin deposi
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After steeping, ke
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0.9994 and 0.9999,
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under acidic and a
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oxidation within t
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colour difference usin</str
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TablesTable 5. 1 - Analyzed proxima
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Effects of
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Effects of
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Effects of
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Effects of
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Data are mean (n=2).a Steepwater pH
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CHAPTER - 6 GENERAL DISCUSSIONCurre
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significant reduction in</s
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Reduction of pigme
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though wheat gluten meal conta<stro
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BibliographyAas, G.H., Storebakken,
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Bjerkeng, B., Hatlen, B., Wathne, E
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Choubert, G., Cravedi, J., Laurenti
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Fauconneau, B., Andre, S., Chmaitil
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Johnston, I., Li, X., Vieira, V., N
Page 161 and 162:
Li, M.H., Oberle, D.F., Lucas, P.M.
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Peter, C.M., Han, Y., Bolin
Page 165 and 166:
Skonberg, D.I., Hardy, R.W., Barrow
Page 167:
Ytrestoyl, T., Struksnæs, G., Kopp
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