The ole o mic owa e abso p ion capaci y and wa e mobili y in he
mic owa e ea men o g ain s. lou : Impac on he ea ed
lou cha ac e is ics
Ainhoa Vicen e
a,b
, Ma ina Villanue a
a,b
, Jose Ma ía Mu˜
noz
b,c
, Ped o A. Caballe o
a,b
,
Felicidad Ronda
a,b,*
a
Depa men o Ag icul u e and Fo es y Enginee ing, Food Technology, College o Ag icul u al and Fo es y Enginee ing, Uni e si y o Valladolid, A . Mad id, 44,
34004, Palencia, Spain
b
Resea ch Ins i u e on Bioeconomy - BioEcoUVa, PROCEREAL ech G oup, Uni e si y o Valladolid, Spain
c
Depa men o Elec ici y and Elec onics, Uni e si y o Valladolid, 47011, Valladolid, Spain
ARTICLE INFO
Keywo ds:
Mic os uc u e
The mal p ope ies
Techno- unc ional p ope ies
Ama an h
Buckwhea
Quinoa
So ghum
The mal ea men
Physical modi ica ion
ABSTRACT
Fou al e na i e c ops (ama an h, buckwhea , quinoa, and so ghum) we e subjec ed o mic owa e-assis ed hea -
mois u e ea men (MWT) unde iden ical condi ions (100 ◦C o 30 min a 25% mois u e con en ) in wo
di e en o ms (g ain and lou ). The e ec s o MWT on he mic os uc u e, he mal p ope ies, and echno-
unc ional p ope ies o he esul ing lou s we e e alua ed. The mic owa e abso p ion capaci y and wa e
mobili y in lou s and g ains du ing hea ing we e also de e mined o explain he di e en impac s o MWT
depending on he ma ix and i s o m. The esul s e ealed ha he mic owa e abso p ion capaci y was com-
pa able o all he samples, wi h wa e being he p ima y mic owa e-abso bing componen . Howe e , a di e en
mobili y and dis ibu ion o wa e du ing hea ing we e obse ed o g ains and lou and among ma ices,
leading o a ia ions in he p ope ies measu ed. The ma ix, he o m o ea men , and hei in e ac ion
signi ican ly in luenced mos o he analysed p ope ies. MWT esul ed in dis up ion o he na i e s uc u e wi h
pa ial usion and loss o in eg i y o cons i uen s, educ ion in gela inisa ion en halpy, inc ease in he ex en o
amylopec in e og ada ion, inc ease in wa e abso p ion capaci y, and dec ease in emulsi ying capaci y. The
wa e abso p ion index and wa e solubili y index showed inc emen s o dec emen s depending on he ma ix
and he o m o ea men . Mo eo e , he MWT o g ain p o ed e ec i e in limi ing he colou change obse ed
in he MWT o lou while enhancing he wa e abso p ion capaci y. These indings highligh he impo ance o
con olling no only he MWT condi ions, bu also he o m o he ma ix, as his in luences he mobili y o wa e
and he inal lou p ope ies.
1. In oduc ion
In ecen yea s, he e has been a g owing in e es in using al e na i e
g ains as ing edien s in ce eal-based oods, pa icula ly glu en- ee
p oduc s. Ce ain mino i y pseudoce eals, such as ama an h, buck-
whea , and quinoa, as well as ce eals, such as so ghum, ha e gained
a en ion because o hei high in insic nu i ional alue (Khoddami
e al., 2023; Ma ínez-Villaluenga e al., 2020). Ama an h and quinoa
a e p o ein- ich wi h a balanced amino acid p o ile and high bioa ail-
abili y, high in die a y ib e, and con ain a lipid ac ion ha is ich in
unsa u a ed a y acids and phy os e ols (Al a ez-Jube e e al., 2010).
Buckwhea is high in polyphenols and agopy i ols (Al a ez-Jube e
e al., 2010). So ghum is o in e es because o i s high die a y ib e and
phenolic compound con en s, as well as i s lowe glycemic index
compa ed o o he ce eals (Khoddami e al., 2023). Howe e , he use o
hese al e na i e lou s in hei na u al o m p esen s limi a ions in
e ms o unc ionali y and senso y quali ies when applied in indus ial
ood p oduc ion (Khoddami e al., 2023; Zhao e al., 2024).
Physical modi ica ion has been widely used o modi y he echno-
unc ional p ope ies o lou s and s a ches o adap hem o he
* Co esponding au ho . Depa men o Ag icul u e and Fo es y Enginee ing, Food Technology, College o Ag icul u al and Fo es y Enginee ing, Uni e si y o
Valladolid, A . Mad id, 44, 34004, Palencia, Spain.
E-mail add ess: [email p o ec ed] (F. Ronda).
Con en s lis s a ailable a ScienceDi ec
Food Hyd ocolloids
jou nal homepage: www.else ie .com/loca e/ oodhyd
h ps://doi.o g/10.1016/j. oodhyd.2024.110680
Recei ed 5 July 2024; Recei ed in e ised o m 22 Augus 2024; Accep ed 24 Sep embe 2024
Food Hyd ocolloids 159 (2025) 110680
A ailable online 24 Sep embe 2024
0268-005X/© 2024 The Au ho s. Published by Else ie L d. This is an open access a icle unde he CC BY-NC-ND license ( h p://c ea i ecommons.o g/licenses/by-
nc-nd/4.0/ ).
equi emen s o he ood indus y (Scha anski e al., 2021; Zhao e al.,
2024). Hea -mois u e ea men (HMT) is a common physical modi i-
ca ion me hod o s a ch/ lou . I in ol es subjec ing s a ch/ lou wi h
limi ed mois u e (10–30%) o empe a u es abo e he glass ansi ion
and below gela inisa ion (90–120 ◦C) o a ce ain pe iod o ime
(Scha anski e al., 2021). Mic owa e adia ion (MW) has been p oposed
as an al e na i e echnology o pe o m HMT, because i is a as p ocess
ha p oduces olume ic hea ing and is en i onmen ally iendly
compa ed o con en ional hea ing. MW can modi y s a ch and p o ein
s uc u es, achie ing di e en esul s depending on he se ing o con-
ol pa ame e s ( empe a u e, mois u e, ime, powe , e c.) and ma ix
cha ac e is ics (Rao e al., 2023; Tao e al., 2020; Zhao e al., 2024).
Mic owa es a e elec omagne ic wa es in he equency ange o 1
GHz–300 GHz, wi h 2.45 GHz being he mos common equency o he
ood indus y and comme cial mic owa es (Villanue a e al., 2018). The
MW elec ic ield is he main agen esponsible o he hea ing. The
in e ac ion be ween his ield and he pola molecules o he ma e ial
h ough hei o a ional elaxa ion p ocesses, esul s in he con e sion o
elec omagne ic ene gy in o hea (Tao e al., 2020). The dielec ic
p ope ies o ma e ials e eal hei in e ac ion wi h elec ic ields, which
is c ucial in mic owa e ea men (MWT) as i in luences he hea ing
cha ac e is ics o he ma e ial (Sosa-Mo ales e al., 2010; Villanue a
e al., 2018). The dielec ic p ope ies o ood depend g ea ly on i s
mois u e, sal , and mine al con en , as ood o ganic cons i uen s can be
conside ed anspa en o MW compa ed o aqueous ionic luids o
wa e (Sosa-Mo ales e al., 2010). Howe e , he dielec ic p ope ies o a
ma e ial a e in luenced no only by he wa e and sal con en bu also
by he way hey a e bonded o es ic ed by o he ood componen s, as
well as he densi y and po osi y o he ma e ial (Sosa-Mo ales e al.,
2010; Tao e al., 2020). The e o e, s udying hese p ope ies is impo -
an o designing and e alua ing he e ec s o MWT on di e en ood
ma ices.
MWT has p ima ily been applied o modi y s a ches, bu in ecen
yea s i has also been e alua ed in mo e complex sys ems such as lou s
and g ains. Buckwhea g ain (Vicen e e al., 2023a), maize g ain (An
e al., 2023), quinoa lou (Cao e al., 2022), quinoa g ain (Vicen e e al.,
2023b), ice lou (Solaesa, Villanue a, Mu˜
noz, & Ronda, 2021; Solaesa,
Villanue a, Vela, & Ronda, 2022; Villanue a e al., 2018), mille lou
(Rao e al., 2023), mille g ain (Zhi e al., 2022), and e lou
(Calix-Ri e a e al., 2023) ha e all been modi ied using MWT. These
s udies ha e shown ha MWT can success ully modi y he mic os uc-
u e, he mal p ope ies, and echno- unc ional p ope ies o he
esul ing lou s, wi h he speci ic modi ica ions a ying depending on
he ma ix and MWT condi ions, which a e no compa able be ween he
di e en s udies ound in he li e a u e. Conduc ing MWT on g ains
o e s se e al indus ial bene i s o e pe o ming i on lou s, including
simpli ied ea men p ocesses, imp o ed homogenei y, and elimina ion
o isks associa ed wi h handling powde y sys ems, e.g., explosi e a -
mosphe es (Vicen e e al., 2023a). Conce ning he MWT e ec , he
pa icle size and in ac plan s uc u e o g ains may a ec he kine ics o
hea ans e and wa e mobili y du ing he MWT, in con as o lou s,
po en ially leading o di e en dielec ic p ope ies. Addi ionally, di -
e ences in wa e mobili y and binding capaci y in di e en g ain
s uc u es, as well as he dis ibu ion and in e ac ion o majo bio-
polyme s, may lead o di e en modi ica ions e en unde he same
MWT condi ions. Howe e , o he bes o ou knowledge, no compa a-
i e s udy has been pe o med on MWT compa ing lou and g ain
ea men .
The e o e, he objec i e o his s udy was o de e mine he e ec o
pe o ming MWT on g ain e sus lou unde he same condi ions
(mois u e con en , empe a u e, and ime) o ou di e en ma ices
(ama an h, buckwhea , quinoa, and so ghum) on he mic os uc u e,
he mal, and echno- unc ional p ope ies o he esul ing lou s. This
comp ehensi e s udy a emp s o unde s and and explain he di e en
impac s o MWT on he esul ing ea ed lou depending on i s sou ce
and o m du ing ea men (g ain o lou ). To achie e his goal, he
abso p ion capaci y and wa e beha iou du ing hea ing o he ea ed
ma ices we e e alua ed. The indings will acili a e he indus ial-scale
applica ion o his echnology.
2. Ma e ials and me hods
2.1. Raw ma e ials
Ama an h g ain (Ama an hus spp.), pu chased on he local ma ke ,
had a p oxima e composi ion (g/100 g g ain d y ma e ) o 14.4 ±0.2%
p o ein, 6.4 ±0.1% a , 2.5 ±0.2% ash, 7.7 ±1.6% die a y ib e, and
54.4 ±0.2% s a ch (5.9 ±0.6% amylose). Dehulled buckwhea (Fag-
opy um esculen um Moench) g ains o Ko a a ie y we e ob ained om
he G upa P oducen ´
ow Ekologicznych Dolina G yki Sp ZOO (Miedzy-
lesie, Poland), and had a p oxima e composi ion (g/100 g g ain d y
ma e ) o 14.5 ±0.1% p o ein, 2.9 ±0.1% a , 1.9 ±0.2% ash, 3.5 ±
0.9% die a y ib e, and 70.8 ±3.4% s a ch (23.6 ±0.2% amylose).
Quinoa (Chenopodium quinoa Willd.) g ains o he Vega osa a ie y we e
p o ided by He ba Ricemills (Se illa, Spain), and he p oxima e
composi ion (g/100 g g ain d y ma e ) was 13.3 ±0.9% p o ein, 2.5 ±
0.1% a , 2.2 ±0.2% ash, 4.9 ±1.2% die a y ib e, and 53.7 ±2.1%
s a ch (10.2 ±0.1% amylose). So ghum (So ghum bicolo L. Moench)
g ains we e p o ided by Salu e (Palencia, Spain) and had a p oximal
composi ion (g/100 g g ain d y ma e ) o 7.5 ±0.5% p o ein, 3.1 ±
0.1% a , 1.6 ±0.2% ash, 7.1 ±1.4% die a y ib e, 73.1 ±0.9% s a ch
(24.5 ±0.6% amylose). P o ein, a , and ash con en s we e de e mined
using he AACC o icial me hods 46–19.01, 30–10.01, and 08–01.01,
espec i ely (AACC, 2010). Die a y ib e con en was de e mined using
he AOAC o icial me hod 991.43 (AOAC, 2023). The o al s a ch con-
en was de e mined wi h he me hod desc ibed by Englys e al. (2006),
and he amylose con en was measu ed using he Conca alin A me hod
(Gibson e al., 1997). The g ains we e g ound in a hamme mill (LM
3100, Pe en Ins umen s, S ockholm, Sweden) wi h a 500
μ
m mesh o
ob ain he un ea ed-na i e lou s.
2.2. Mic owa e abso p ion capaci y
The mic owa e abso p ion capaci y o he un ea ed/na i e g ains
and lou s o ama an h, buckwhea , quinoa, and so ghum, was de e -
mined using a Keysigh E5071C ne wo k analyse (Agilen , CA, USA)
ollowing he me hod desc ibed by Villanue a e al. (2018) wi h sligh
modi ica ions. The wo po s o he ne wo k analyse we e connec ed ia
coaxial lines and a enua o s (20 dB) o wo coaxial wa eguide ansi-
ions (SMA o WR34) aligned and aced each o he a a cons an dis ance
o 11 mm. Foam abso be s we e added o elimina e esonan modes o
he sample holde . The measu emen s we e pe o med on samples a
25% MC (mois u ized as desc ibed in 2.4 sec ion) and a 2% mois u e
con en (MC) ( eeze-d ied wi h a LyoQues 55Plus (Tels a , Te assa,
Spain)). Samples a he desi ed MC we e weigh ed and homogenously
dis ibu ed in Pe i dishes. The sca e ing coe icien S
12
was measu ed
in duplica e a 2.45 GHz. The equipmen was calib a ed wi h an emp y
Pe i dish o 0 dB and 0 ad o phase angle. Mic owa e abso p ion was
quan i ied in e ms o a enua ion and phase change using he ollowing
equa ions:
α
=20⋅log S12( illed)
S12(emp y)(1)
Θ=a g S12( illed)
S12(emp y)(2)
whe e
α
is he a enua ion, Θ is he phase shi , S
12
( illed) is he sca -
e ing coe icien when he sample con aine is illed wi h he sample,
and S
12
(emp y) when i is emp y.
To apply he Lambe -Bee law, he measu emen was no malised o
he sample weigh , since he op ical pa h canno be comple ely illed
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
2
wi h he sample and includes he ai apped be ween he pa icles. The
a enua ion was he e o e exp essed in dB/kg and he phase shi in ad/
kg.
2.3. Wa e beha iou du ing he hea ing p ocess: d ying cu es
The d ying cu es o he na i e lou s and g ains we e ob ained
using a he mobalance MB120 (Ohaus, USA). A sample o 5.00 ±0.01 g
was weigh ed in o an aluminium pan and hen hea ed a 100 ◦C o 60
min. The weigh was au oma ically eco ded e e y 5 s wi h an accu acy
o 0.001 g. The mois u e a io (MR) was de e mined using he expe i-
men al da a ob ained a each ime in e al, as epo ed by Sadaka
(2022), using he ollowing equa ion:
MR = (M−Me)/(M0−Me)(3)
whe e M is he mois u e con en a ime , M
0
is he ini ial mois u e
con en , and M
e
is he equilib ium mois u e con en , which was
neglec ed as commonly epo ed by p e ious au ho s u ilizing his
model (Tog ul & Pehli an, 2002). All mois u e con en s a e e e ed o
d y basis (db).
The d ying cu es ob ained om he expe imen s (MR s ime) we e
i ed o se e al d ying kine ic models (Sadaka, 2022). The bes - i
model was he Loga i hmic model (Onwude e al., 2016):
MR =a⋅exp(− k⋅ ) + b(4)
whe e a and b a e empi ical cons an s (dimensionless), k is he d ying
cons an (min
−1
), and is he hea ing ime (min).
2.4. Mic owa e ea men
Na i e g ains and lou s o ama an h, buckwhea , quinoa, and so -
ghum we e mois u ized o ob ain 25% MC by adding dis illed wa e
while mixing (Vicen e e al., 2023a). MC was de e mined acco ding o
he AACC o icial me hod 44–15.02 (AACC, 2010). Mic owa e ea -
men was pe o med a 900 W and 2450 MHz using a cus omized mi-
c owa e o en R342INW (SHARP, Sakai, Japan), wi h a
compu e -con olled sys em o egula e he mic owa e applica ion
pa e n and ime acco ding o he p og ammed empe a u e. To pe o m
he ea men , 120 ±0.05 g o g ain o lou we e placed in o a 250 mL
he me ic and hea - esis an bo osilica e glass con aine . The o al
ea men du a ion was 30 min. The i s 5 min we e dedica ed o
hea ing he sample om oom empe a u e (22 ±2 ◦C) o 100 ◦C. The
empe a u e was hen main ained a 100 ±3 ◦C o he emaining 25
min. Each ea men was pe o med in iplica e. In addi ion, a em-
pe a u e da a logge (Pico VACQ, TMI-O ion, Cas elnau-le-Lez, F ance)
was placed inside he essel in con ac wi h he sample o eco d he
empe a u e e olu ion du ing he ea men . The ob ained lou s and
g ains we e d ied a 35 ◦C o he na u al mois u e con en o he o iginal
g ains/ lou s (11–14%). The g ains we e hen milled using a hamme
mill (LM 3100, Pe en Ins umen s, S ockholm, Sweden) wi h a 500
μ
m
mesh (iden ical condi ions o na i e g ain milling). The ea ed lou s
we e disagg ega ed using a s one mill Fidibus Medium (Komo, Hop -
ga en, Aus ia). The lou samples we e named wi h h ee le e s, XX-Y,
acco ding o he ea men (XX) and he ma ix (Y) as un ea ed/na i e
(UN), ea ed in he o m o g ain (TG), o ea ed in he o m o lou
(TF), ama an h (A), buckwhea (B), quinoa (Q), o so ghum (S). This
combina ion esul ed in 12 samples.
2.5. Pa icle size dis ibu ion
The pa icle size dis ibu ion o he lou s was s udied using a lase
di ac ion pa icle size analyse (Mas e size 2000, Mal e n In-
s umen s L d., Mal e n, UK) wi h a pa icle e ac i e index o 1.53.
The measu emen s we e pe o med in iplica e. The esul s we e
exp essed as D
10
, D
50
(median diame e ), and D
90
, ep esen ing he
diame e a which 10%, 50%, and 90% o he pa icles ha e a smalle
size, espec i ely. The a i hme ic mean diame e o he lou was also
de e mined. The size o he g ains and hei a i hme ic mean diame e
we e de e mined by image analysis o g ain images aken wi h a Pow-
e Sho SX410 IS came a (Canon, Japan) using he ImageJ so wa e
(Na ional Ins i u es o Heal h, USA).
2.6. Scanning elec on mic oscopy (SEM)
The mo phological changes o he na i e and ea ed g ains (g ains
cu in hal wi h a scalpel) and ea ed lou s we e s udied using a mi-
c oscope (Quan a 200-F, FEI, G az, Aus ia) equipped wi h an X- ay
de ec o . The samples we e moun ed on o aluminium s ubs using
conduc i e ca bon ape and coa ed wi h a 5 nm laye o gold using a
spu e coa e (SCD-05, Leica Mic osys ems, We zla , Ge many). The
analysis was pe o med in low- acuum mode, a an accele a ion ol age
o 2–5 keV, using a seconda y elec on de ec o . Mic og aphs we e aken
a a ious magni ica ions, and ep esen a i e images we e selec ed o
illus a e mic os uc u al changes.
2.7. Colou cha ac e is ics
Flou colou was measu ed in sex uplica e using a PCE-CSM5 col-
ou ime e con olled by he CQCS3 so wa e. The CIE L*a*b* and CIE
L*C*h coo dina es we e de e mined wi h D65 s anda d illuminan and
10◦s anda d obse e . The colou di e ence (ΔE) be ween each ea ed
sample and he co esponding un ea ed lou o he same ma ix was
calcula ed using he ollowing equa ion:
ΔE=[(ΔL*)2+ (Δa*)2+ (Δb*)2]1/2(5)
2.8. Di e en ial scanning calo ime y (DSC)
The gela inisa ion and e og ada ion ansi ions o he lou samples
we e de e mined in duplica e using a di e en ial scanning calo ime e
(DSC3, STARe-Sys em, Me le -Toledo, Swi ze land). App oxima ely 6
mg o lou we e weighed in o 40 mL aluminium pans, and dis illed
wa e was added o ob ain a wa e : lou a io o 70:30. The samples
we e scanned om 0 o 120 ◦C a 5 ◦C/min using an emp y pan as a
e e ence. The gela inised sample was subsequen ly s o ed a 4 ◦C o
se en days be o e being escanned o e alua e e og ada ion. The
en halpy (ΔH), exp essed as J/g o lou db, and he peak (T
p
), onse
(T
o
), and endse (T
e
) empe a u es we e de e mined o each o he
de ec ed peaks.
2.9. Techno- unc ional p ope ies
The hyd a ion p ope ies o he lou s in e ms o wa e abso p ion
capaci y (WAC), oil abso p ion capaci y (OAC), wa e abso p ion index
(WAI), and wa e solubili y index (WSI) we e measu ed a 5% concen-
a ion, ollowing he me hod desc ibed by Abebe e al. (2015) wi h
modi ica ions by Vicen e e al. (2023a). WAC and OAC esul s we e
exp essed as g ams o wa e o oil e ained pe g am o lou db, WAI as
g ams o sedimen pe g am o lou db, and WSI as g o soluble solids pe
100 g o lou db. Emulsi ying ac i i y (EA) and emulsion s abili y (ES)
we e de e mined as desc ibed by Kaushal e al. (2012) wi h modi ica-
ions by Vicen e e al. (2023a). EA and ES we e exp essed as pe cen ages
o he olume o emulsion o med and he emulsion olume a e
hea ing, espec i ely, in ela ion o he ini ial olume.
Techno- unc ional p ope ies we e measu ed a leas in iplica e.
2.10. S a ical analysis
S a is ical analysis was conduc ed using S a g aphics Cen u ion 19
so wa e (Bi s eam, Camb idge, MN, USA). To assess signi ican di -
e ences (p <0.05) be ween samples, he leas signi ican di e ence
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
3
(LSD) analysis o a iance (ANOVA) was used. The esul s we e p e-
sen ed as he mean alues o he di e en eplica es and hei s anda d
de ia ions. The expe imen al da a o he d ying cu es we e i ed using
O iginP o 2023 (No hamp on, MA, USA). The alues o he adjus ed
coe icien o de e mina ion (adj-R
2
) and Chi-Squa e (X
2
) we e e alu-
a ed o de e mine he bes - i ing model (highe R
2
and lowe X
2
).
Loga i hm was employed o no malize he da a and e alua e signi ican
di e ences in he a i hme ic mean diame e be ween lou s and g ains.
3. Resul s and discussion
3.1. Mic owa e abso p ion capaci y and d ying cu es
The mic owa e abso p ion capaci y o he un ea ed lou s and
g ains was e alua ed in e ms o a enua ion and phase shi a MC
alues o 25% and 2% (Table 1). The esul s showed no signi ican di -
e ences in he a enua ion and phase shi a he same MC be ween he
samples. Howe e , he a enua ion was app oxima ely 30 imes highe
o 25% MC han o 2% MC, he la e being a he limi o de ec ion o
he equipmen . The o ganic cons i uen s can be conside ed dielec ically
ine and anspa en o MW compa ed o aqueous ionic luids o wa e
(Sosa-Mo ales e al., 2010). Ou indings a e consis en wi h hose e-
po ed by Villanue a e al. (2018) o ice lou . These au ho s showed
ha wa e is he main esponsible o mic owa e abso p ion, because
he mois u e con en o he lou de e mined he a enua ion and
phase-shi , wi h he a enua ion p ac ically null in he absence o wa e .
Addi ionally, ou s udy ound no signi ican di e ences in mic owa e
abso p ion capaci y be ween he ma ices s udied, ega dless o whe he
hey we e analysed in he o m o lou o g ain. Howe e , since he
wa e in he p oduc is esponsible o he con e sion o mic owa e
ene gy in o he mal ene gy, he dis ibu ion o wa e du ing ea men
and i s beha iou and mobili y du ing hea ing should play a c ucial ole
in he modi ica ion achie ed a e he MWT o g ains in compa ison o
lou s.
To e alua e he wa e mobili y in he ma ices s udied du ing hea -
ing, samples a 25% MC we e submi ed o a d ying p ocess a 100 ◦C
(MWT empe a u e). The d ying cu es ob ained a e p esen ed in Fig. 1;
Table 1 shows he d ying pa ame e s ob ained a e i ing he cu es o
a loga i hmic model. The mean diame e o lou pa icles and g ains is
also included in Table 1, as he size o pa icles/g ains a ec s he wa e
loss kine ics. The loga i hmic model is a semi- heo e ical model based
on Fick’s second law o di usion and has been widely applied o model
he d ying kine ics o oods u s (Onwude e al., 2016; Sadaka, 2022)
when sho -/medium- e m d ying p ocesses a e modelled. The model
e ec i ely desc ibed he e olu ion o he mois u e a io o e ime du ing
he d ying p ocess o bo h g ain and lou o he ou ma ices, p e-
sen ing an adjus ed coe icien o de e mina ion (Adj-R
2
) >0.989 o all
samples. In addi ion, he “b” pa ame e ob ained om he i ing was
close o he expe imen al MR alue a he longes d ying ime s udied (1
h); while he addi ion o a+b was close o 1, as expec ed om he model,
since MR a =0 mus be equal o 1 (whe e M =M
0
). This explains why
when he pa ame e “a” dec eased “b” inc eased, showing a s ong
nega i e co ela ion be ween hem ( = − 0.984, p <0.001). The d ying
a e cons an , k, was highe o lou s han o g ains, indica ing as e
d ying o he lou s, in he o de o ama an h lou >so ghum lou >
buckwhea lou =quinoa lou >ama an h g ain >quinoa g ain >
buckwhea g ain >so ghum g ain. The d ying a e was s ongly co e-
la ed wi h he mean diame e o he g ain/ lou ( = − 0.975, p <0.001),
which indica es smalle pa icle size led o as e d ying. The lowe “a”
and highe “b” pa ame e s o g ains compa ed o lou s also indica e he
g ea e di icul y o g ains in wa e loss du ing d ying. I is no ewo hy
ha his model can accu a ely desc ibe he d ying kine ics o he d ying
Table 1
Mic owa e abso p ion capaci y and d ying kine ic cons an s o na i e lou s and g ains.
A enua ion (dB/kg) Phase shi ( ad/kg) D ying cu es i ing pa ame e s Diame e (mm)
Sample 25% MC 2% MC 25% MC 2% MC a k (min
−1
) b X
2
Adj-R
2
Ama an h lou 26.9 ±3.0
a
0.8 ±0.4
a
17.8 ±1.1
a
7.8 ±0.1
a
1.061 ±0.001 e 0.243 ±0.005
g
0.044 ±0.001 c 0.0001 0.9962 0.172 ±0.003
c
Ama an h g ain 28.3 ±0.1
a
2.4 ±0.2
a
16.2 ±0.1
a
7.8 ±0.2
a
0.876 ±0.008
b
0.168 ±0.007
d
0.145 ±0.005 0.0003 0.9894 12.2 ±0.8 d
Buckwhea lou 31.3 ±2.4
a
1.1 ±0.7
a
17.9 ±0.4
a
7.5 ±0.1
a
1.085 ±0.007 0.207 ±0.013
e
0.037 ±0.006
bc
0.0002 0.9958 0.113 ±0.002
a
Buckwhea
g ain
28.0 ±0.3
a
1.8 ±0.2
a
15.8 ±0.2
a
7.5 ±0.2
a
0.932 ±0.005
d
0.091 ±0.001
b
0.107 ±0.003 d 0.0001 0.9989 37.5 ±2.9
Quinoa lou 26.2 ±0.7
a
1.6 ±0.8
a
16.1 ±0.8
a
7.8 ±0.1
a
1.100 ±0.009 g 0.205 ±0.008
e
0.020 ±0.007 a 0.0001 0.9965 0.149 ±0.015
b
Quinoa g ain 30.8 ±0.7
a
2.3 ±0.3
a
16.9 ±0.1
a
7.8 ±0.1
a
0.916 ±0.007 c 0.131 ±0.001
c
0.116 ±0.005 e 0.0002 0.9950 19.3 ±1.9 e
So ghum lou 27.3 ±1.5
a
1.0 ±0.1
a
17.4 ±0.4
a
7.4 ±0.1
a
1.092 ±0.008
g
0.220 ±0.005 0.035 ±0.005 b 0.0002 0.9954 0.170 ±0.011
c
So ghum g ain 28.6 ±0.3
a
2.2 ±0.2
a
16.8 ±0.3
a
7.9 ±0.1
a
0.799 ±0.008 a 0.062 ±0.001
a
0.221 ±0.006 g 0.0001 0.9995 38.0 ±2.1
MC: mois u e con en . The d ying kine ic cons an s we e ob ained a e he adjus men o he loga i hmic model [MR =a⋅exp( − k⋅ ) + b], whe e MR is he mois u e
a io ( e e o sec ion 2.3), k he d ying cons an (min
−1
), and a and b a e empi ical cons an s. Adj-R
2
is he adjus ed coe icien o de e mina ion and X
2
is he Chi-
Squa e o he i ing model. Da a is exp essed as mean ±s anda d de ia ion. Signi ican s a is ical di e ences (p <0.05) a e indica ed by di e en le e s o he same
pa ame e . Diame e e e s o he a i hme ic mean o pa icles/g ains conside ed sphe ical.
Fig. 1. D ying cu es a 100
◦C showing he e olu ion o he mois u e a io
(MR) wi h ime o na i e lou s and g ains wi h an ini ial mois u e con en
o 25%.
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
4
ime employed (1 h). A 1 h, he i s e m o he equa ion, which in-
cludes he independen a iable “ ”, becomes nea ly ze o and he MR
alue is p ac ically equal o he “b” alue. Consequen ly, he cons an
“b” ep esen s he esidual MR a he end o he s udied d ying pe iod.
Ne e heless, he ele a ed alues o he pa ame e “b" o g ains sugges
ha adjus ing o a model wi h addi ional exponen ial e ms and wi hou
an independen e m may be ad an ageous o long- e m d ying p o-
cesses, as a MR alue should be nea ze o a in ini e d ying ime.
Onwude e al. (2016) epo ed ha he empe a u e and hickness o
d ying ma e ial we e he mos in luen ial ac o s a ec ing he d ying
kine ics o ood p oduc s. The mois u e dis ibu ion wi hin he pa icles
du ing MWT can signi ican ly a ec he modi ica ions ob ained, as
mois u e is a key pa ame e in de e mining he e ec o HMT
(Scha anski e al., 2021). This is pa icula ly impo an in MWT, as
wa e abso bs MW and p oduces he hea ing ha he sample uses o
inc ease i s empe a u e. Du ing he ini ial s ages o MWT, wa e mo es
om he inne o he ou e laye s o lou pa icles/g ains, depending
g ea ly on pa icle size. This beha iou occu ed apidly in he case o
lou . Fo example, in he d ying models, lou pa icles we e almos
comple ely d y wi hin he i s 10 min. Howe e , o g ains, his p ocess
was much slowe , and signi ican mois u e con en emained e en a e
30 min (see Fig. 1). MWTs a e usually pe o med unde non-he me ic
condi ions whe e he sample is unde a mosphe ic p essu e and is
nea ly comple ely d ied a e ea men (Villanue a e al., 2018). This is
he case in many s udies ca ied ou a labo a o y scale, and mos o he
ea men s pe o med a indus ial le el. In ou s udy, he sample was
in oduced in o a he me ic con aine , and a he end o ea men , a e
cooling, he MC was no modi ied. The e o e, one could hink i is no
possible o ex apola e his model esul s o ou mic owa e sys em
di ec ly; howe e , i can be concluded ha di e ences in mois u e
con en and dis ibu ion wi hin he lou pa icles and g ains will occu
du ing ea men . This will p obably lead o no able a ia ions in he
physical modi ica ion o lou s compa ed wi h g ains. The smalle lou
pa icles will d y quickly in e nally and ha e hei su ace su ounded
by he e apo a ed wa e , which will occupy a la ge headspace inside he
con aine whe e he sample is being ea ed. So, he eal/ac ual MC o
he sample du ing he ea men when he sample eaches 100 ◦C mus
be below he ini ial MC, e en i i is highe han could be expec ed unde
open/no -he me ic condi ions. The la ge g ain pa icles will d y mo e
slowly, p esen ing mo e mois u e inside he g ain o a longe ime.
3.2. Mic owa e ea men
Fig. 2 shows he sample empe a u e e olu ion eco ded du ing
MWT. The empe a u e o he sample inc eased om 22 ±2 ◦C o 100 ±
3 ◦C in 5 min and was main ained a 100 ±3 ◦C o he emaining 25
min. To achie e he desi ed empe a u e p o ile, he MW ene gy (a
maximum powe o 900 W) was applied in e mi en ly o 3.6 ±0.2 min
o e he 30 min ea men , equi ing 1.5 ±0.1 min o inc ease he
empe a u e in he amp ( i s 5 min) and hen 2.1 ±0.1 min o main ain
he empe a u e in he pla eau ( emaining 25 min). The con ol sys em
au oma ically adjus ed he MW applica ion o main ain he desi ed
empe a u e. The e we e no signi ican di e ences be ween he samples
in he o al MW ime needed o inc ease and main ain he sample em-
pe a u e du ing MWT. This inding aligns wi h he esul s o MW ab-
so p ion capaci y, which iden i ied wa e con en as he sole ac o
signi ican ly in luencing MW abso p ion. The empe a u e cu e and
con ol sys em we e di e en om hose in ou p e ious s udies, in
which a cons an mic owa e cycle o seconds o exposu e and seconds o
es was applied, and a longe mic owa e ime o 3–5 min was equi ed
o each he pla eau empe a u e, compa ed o 1.5 min in his s udy
(Solaesa e al., 2021; Villanue a e al., 2018). This app oach is simila o
adi ional HMT, whe e a ixed ea men empe a u e and ime a e se
in he o en, and he sample is ea ed unde hese condi ions, p og es-
si ely inc easing i s empe a u e un il he objec i e is achie ed
(Scha anski e al., 2021). Howe e , ou new app oach uses he
ad an age o MW echnology, whe e hea is gene a ed inside he sample,
as wa e abso bs MW adia ion and ans o ms i in o hea , esul ing in a
as e empe a u e ise and mo e e icien ene gy use, allowing he o al
ea men ime and ene gy o be educed.
3.3. Pa icle size dis ibu ion
The pa icle size pa ame e s o he lou s ob ained a e MWT o
lou s and g ains, measu ed by lase di ac ion, a e p esen ed in
Table 2. The pa icle size pa ame e s ob ained a e ea ing and milling
he samples we e signi ican ly a ec ed by he ma ix, ea men , and
hei in e ac ion. Pa icle size di e ences should be aken in o consid-
e a ion when compa ing ea men e ec s as hey ha e an impac on he
echno- unc ional and he mal p ope ies o lou (An e al., 2023; Yang
e al., 2017). The mos ema kable e ec o MWT was he inc ease in he
pa icle size o he small ac ion, as obse ed o he highe D
10
o all
ea ed samples; his e ec was mo e in ense o he lou ea men (see
Supplemen a y Fig. 1). The la ges di e ences in D
10
we e obse ed o
buckwhea , wi h a 254% inc ease o TF-B and a 127% inc ease o TG-B
compa ed o UN-B. The smalles di e ences we e obse ed in so ghum,
wi h inc eases o 41% and 20% compa ed o UN-S o TF-S and TG-S,
espec i ely. The median diame e (D
50
) and he diame e o he 90 h
pe cen ile (D
90
) o he ea ed buckwhea and quinoa samples showed a
signi ican inc ease compa ed o he un ea ed lou . Howe e ,
ama an h and so ghum showed no signi ican di e ences, wi h he
excep ion o TF-A. P e ious s udies ha e epo ed inc eased pa icle size
a e MWT, wi h di e en impac s depending on he ma ix and ea -
men condi ions (An e al., 2023; Calix-Ri e a e al., 2023; Vicen e e al.,
2023a). The au ho s associa ed he inc ease in pa icle size wi h modi-
ica ions in he componen s uc u e esul ing om MWT, such as s a ch
gela inisa ion and p o ein dena u a ion, which may induce agg ega es,
making milling mo e di icul and esul ing in an inc eased pa icle size,
pa icula ly in ob aining he smalles pa icles.
3.4. Mo phology
Fig. 3 shows SEM mic og aphs o he endospe m pa icles o he
s udied samples be o e milling ob ained a a magni ica ion o 6000 ×.
Supplemen a y Fig. 2 displays mic og aphs o he same a ea a a wide
ange o magni ica ions (500 ×, 1000 ×, 3000 ×, and 6000 ×). The
appea ance and s uc u e o he di e en ma ices a ied conside ably.
Ama an h p esen s small polygonal s a ch g anules (0.5–2
μ
m) in a e y
compac ma ix (Pe ez-Rea & An ezana-Gomez, 2018). Quinoa also has
small polygonal g anules (1–2
μ
m) ha a e p esen ed indi idually o as
sphe ically packed agg ega es in he endospe m (Vicen e e al., 2023b).
Buckwhea s a ch g anules a y in shape, being polygonal o sphe ical,
Fig. 2. E olu ion o sample empe a u e du ing mic owa e ea men .
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
5
wi h a size o 2–15
μ
m, and a e packed in clus e s o di e en sizes, wi h
hin memb anes and p esen ing a ached o en wined p o ein pa icles
(Pe ez-Rea & An ezana-Gomez, 2018). So ghum endospe m has
co neous and lou y zones wi h s a ch g anules o 5–30
μ
m o ganised in
cells wi h a p o ein ma ix, wi h highe p o ein abundance in he
co neous endospe m (Khoddami e al., 2023). The applica ion o MWT
esul ed in a dis up ion o he na i e s uc u e o all ma ices, causing
pa ial usion o he s uc u es and a loss o in eg i y o bo h he s a ch
and p o ein cons i uen s. O he s udies ha ha e e alua ed he MWT o
lou s o g ains ha e epo ed simila obse a ions in he su ace aspec
o pa icles a e ea men wi h maize g ain (An e al., 2023) and ice
lou (Solaesa e al., 2022). These obse a ions ha e been linked o he
pa ial pas ing o s a ch g anules wi h amylose exuda ion, and o p o ein
dena u a ion, esul ing in he o ma ion o la ge agglome a es. The
ea men o lou esul ed in pa icles wi h a su ace ha had mo e
used s uc u es han he g ain ea men . This could be due o
con inuous exposu e o he pa icle su ace o he su ounding wa e . In
con as , he s a ch in he inne pa o he g ain would ha e been
exposed o less wa e , especially owa ds he end o he ea men ,
limi ing he modi ica ion. I is impo an o no e ha he modi ica ion
may no be homogeneous wi hin he lou pa icles and g ains due o he
non-uni o m dis ibu ion o wa e inside hem du ing ea men . These
di e ences may lead o a ia ions in he esul ing lou cha ac e is ics
gi en ha wa e plays a key ole in MWT modi ica ion.
3.5. Colou cha ac e is ics
Table 2 p esen s he colou cha ac e is ics o he lou s ob ained a e
MWT o lou s and g ains. The colou pa ame e s we e signi ican ly (p
<0.001) in luenced by ma ix, ea men , and hei in e ac ion. Fo all
ma ices, MWT signi ican ly educed Luminosi y (L*) and inc eased
Ch oma (C*) alues, wi h a mo e p onounced e ec obse ed when he
ea men was pe o med in lou . Ama an h, buckwhea , and quinoa
showed highe hue (h) in he na i e lou han in he ea ed lou ,
whe eas so ghum showed he opposi e e ec . Ob aining a da ke and
mo e i id colou is a common esul a e MWT o g ains and lou s,
while he modi ica ion o hue a ied depending on he ma ix and
ea men (Sha anaga e al., 2019; Solaesa e al., 2021; Vicen e e al.,
2023a, 2023b). The colou change has been associa ed wi h Mailla d
eac ion and ca amelisa ion (Solaesa e al., 2021), and polyphenol
oxida ion (Sha anaga e al., 2019) du ing MWT. The colou di e ence
(ΔE) was highe when MWT was pe o med on lou , eaching up o 13.6
o TF-B, he ma ix wi h he highes polyphenol con en
(Al a ez-Jube e e al., 2010). Howe e , he ΔE was much lowe o g ain
ea men , wi h a maximum o 5.1 o TG-B and less han 5 o he o he
ma ices. No ably, ΔE <5 is ba ely pe cep ible o he human eye
(Ga cía-Vigue a & Za illa, 2001). Pe o ming MWT on lou s would
ha e inc eased he con ac be ween polyphenols and enzymes, and be-
ween p o eins and educing suga s, hus acili a ing he oxida ion o
polyphenols and he Mailla d eac ion, espec i ely, esul ing in mo e
colou ed compounds ha inc eased ΔE. Howe e , an in ac g ain
s uc u e would ha e limi ed he con ac be ween he compounds
in ol ed in he eac ions, he eby limi ing hem and educing ΔE.
The e o e, pe o ming MWT on g ains appea s o be an e ec i e
app oach o minimizing he e ec o he mal ea men on colou .
3.6. The mal p ope ies
Table 3 p esen s he he mal p ope ies o he lou samples ob ained
by DSC, and he he mog ams a e shown in Supplemen a y Fig. 3. The
gela inisa ion scan, pe o med on esh samples, showed wo endo-
he mic peaks. The i s peak, associa ed wi h gela inisa ion, is ela ed o
he mel ing o amylopec in c ys alli es (Biliade is, 2009). The gela ini-
sa ion en halpy, ΔH
gel
, dec eased wi h ea men o all ma ices,
anging om −9% (TF-A) o −29% (TF-Q). The e we e no signi ican
di e ences (p >0.05) be ween g ain and lou ea men s o he same
ma ix. The dec ease in ΔH
gel
was accompanied by an inc ease in he
onse , peak, and endse empe a u es (T
o-gel
, T
p-gel
, and T
e-gel
, espec-
i ely) ha a ied be ween +1.9 ◦C (TG-Q) and +4.3 ◦C (TG-B) o T
o-gel
.
Ama an h and buckwhea exhibi ed a delay in T
o-gel
when compa ing
g ain ea men wi h lou ea men (+0.5 ◦C o TG-A compa ed o
TF-A, and +1.5 ◦C o TG-B compa ed o TF-B). In con as , quinoa and
so ghum showed he opposi e beha iou , wi h g ea e delay when he
ea men was applied o lou (+1.1 ◦C o TF-Q compa ed o TG-Q and
+0.9 ◦C o TF-S compa ed o TG-S). This beha iou , p e iously e-
po ed o MWT o a ious ma ices, may be mainly a ibu ed o ea -
angemen s o c ys alline and amo phous egions o s a ch du ing MWT
(Zhao e al., 2024). The s a ch would ha e pa ially gela inised, wi h
g ea e dis up ion o he weake c ys als and he double helix s uc u e
wi hin he s a ch, esul ing in a dec ease in ΔH
gel
and a delay in T
o-gel
(An e al., 2023; Cao e al., 2022). The ea angemen s be ween he
amo phous and c ys alline egions may ha e imp o ed
Table 2
Pa icle size and colou cha ac e is ics o lou samples ob ained om un ea ed
and mic owa e- ea ed lou s and g ains.
Sample D
10
D
50
D
90
L* C* h ΔE
UN-A 23
±3
a
140
±2 a
322
±6 b
85.7
±0.5
c
13.8
±0.8
a
69.1
±0.6
b
–
TF-A 47
±1
c
138
±2 a
277
±5 a
80.6
±0.9
a
19.2
±0.2
b
68.8
±0.2
ab
7.5 ±
0.6 b
TG-A 30
±3
b
144
±13
a
333
±23
b
85.0
±0.3
b
14.2
±0 a
68.4
±0.3 a
0.9 ±
0.2 a
UN-B 9 ±
1 a
83 ±
1 a
226
±6 a
88.3
±0.2
c
8.0 ±
0.1 a
74.2
±0.6 c
–
TF-B 33
±3
c
110
±2 c
296
±8 c
75.0
±0.4
a
9.9 ±
0.2 c
60.4
±0.3 a
13.6
±0.4
b
TG-B 21
±2
b
94 ±
2 b
256
±18
b
83.6
±0.2
b
8.2 ±
0.1 b
61.2
±0.1
b
5.1 ±
0.2 a
UN-Q 13
±3
a
113
±15
a
314
±19
a
90.7
±0.6
c
11.1
±0.2
a
82.1
±0.9 c
–
TF-Q 26
±1
c
143
±2 b
346
±4 b
85.8
±0.1
a
14.5
±0.1
c
74.4
±0.2 a
6.2 ±
0.2 b
TG-Q 21
±1
b
143
±7 b
354
±5 b
88.0
±0.2
b
11.8
±0.2
b
78.7
±0.5
b
2.9 ±
0.2 a
UN-S 17
±2
a
135
±12
a
345
±15
a
81.6
±0.6
c
9.8 ±
0.5 a
60.1
±0.3 a
–
TF-S 24
±1
c
142
±5 a
332
±11
a
74.8
±1.2
a
11.9
±0.2
c
64.1
±0.2 c
7.2 ±
0.9 b
TG-S 20
±1
b
141
±1 a
352
±3 a
79.3
±0.5
b
11.4
±0.4
b
63 ±
0.3 b
2.9 ±
0.5 a
Analysis o a iance and signi icance (p- alues)
Ma ix (F1) *** *** *** *** *** *** ***
T ea men
(F2)
*** *** *** *** *** *** ***
F1 x F2 *** ** *** *** *** *** ***
Flou s ob ained om un ea ed-na i e g ain (UN), mic owa e- ea ed g ain
(TG), and mic owa e- ea ed lou (TF) o ama an h (A), buckwhea (B), quinoa
(Q), and so ghum (S). D
10
, D
50
, and D
90
: diame e whe e 10%, 50%, and 90% o
pa icles ha e a smalle size, espec i ely L*: luminosi y; C*: ch oma; h: hue; ΔE:
colou di e ence om un ea ed-na i e lou . Da a is exp essed as mean ±
s anda d de ia ion. Signi ican s a is ical di e ences (p <0.05) a e indica ed by
di e en le e s o he same pa ame e and ma ix. Analysis o a iance and
signi icance o ma ix (A,B,Q,S), ea men (UN, TG, TF), and hei in e ac ion:
***p <0.001, **p <0.01, *p <0.05, ns: non-signi ican .
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
6
amylose-amylose and amylose-amylopec in in e ac ions, esul ing in
inc eased T
o-gel
, T
p-gel
, and T
e-gel
(An e al., 2023; Zhao e al., 2024).
The second peak o he gela inisa ion scan, which occu ed a
94–98 ◦C, is ypically associa ed wi h amylose-lipid dissocia ion
(Biliade is, 2009), al hough i could also be ela ed o p o ein dena u -
a ion in lou s wi h high p o ein con en , as some p o eins exhibi a
dena u a ion peak a hese empe a u es (Janssen e al., 2017). This
peak was de ec able in all na i e samples, al hough i had a e y low
en halpy (ΔH
2
1s ) o ama an h and quinoa (<0.5 J/g db). MWT
educed ΔH
2
1s o so ghum, buckwhea , and quinoa (wi h no de ec -
able peak o TF-Q and TG-Q), bu no signi ican di e ences we e
obse ed o ama an h. In he e og ada ion scan, he second peak was
no de ec ed in ama an h and quinoa samples, al hough i was obse ed
in he i s scan. The peak o amylose-lipid dissocia ion is e e sible
(Biliade is, 2009). Consequen ly, he second peak obse ed in he
gela inisa ion scan o quinoa and ama an h may be a ibu ed o p o ein
dena u a ion, as i was no ound o be e e sible because i did no
eappea in he e og ada ion scan. E en a e successi e cooling and
hea ing cycles, he complex ailed o e o m (da a no shown). Quinoa
and ama an h p o ein isola es ha e been shown o ha e a p o ein
dena u a ion peak a ound 94–100 ◦C (Janssen e al., 2017). In addi ion,
he disappea ance o he peak o quinoa- ea ed samples and he sligh
educ ion (no signi ican , p >0.05) o ama an h- ea ed samples may
be ela ed o pa ial p o ein dena u a ion du ing he MWT. Fo UN-B and
UN-S, a sligh ly highe en halpy o he second peak was obse ed in he
e og ada ion scan han in he gela inisa ion scan. This beha iou is
consis en wi h ha o amylose-lipid dissocia ion, as an inc ease in he
en halpy o his peak upon ehea ing has been commonly epo ed
because o he be e condi ions o complex o ma ion when amylose
has al eady leaked om s a ch g anules du ing gela inisa ion (Eliasson,
1994). Howe e , a signi ican educ ion in en halpy (p <0.05) was
obse ed a e MWT o buckwhea and so ghum when applied in g ain
o m, bu no when applied o lou . This beha iou has al eady been
epo ed o ea ed buckwhea g ains and linked o he o ma ion o
amylose-polyphenol complexes (Vicen e e al., 2023a).
The i s peak in he e og ada ion scan was iden i ied in all samples
and was ela ed o he mel ing o ec ys allised amylopec in (Biliade is,
2009). Ama an h showed a mino e og ada ion peak ha was no
a ec ed by he ea men . Buckwhea , quinoa, and so ghum showed an
inc eased deg ee o e og ada ion a e MWT. Inc eased e og ada ion
en halpy has been epo ed a e MWT o buckwhea (Vicen e e al.,
2023a), quinoa (Vicen e e al., 2023b), and ice (Villanue a e al.,
2018), whe eas no signi ican inc ease was obse ed o e
(Calix-Ri e a e al., 2023), quinoa (Vicen e e al., 2023b), and ice
(Solaesa e al., 2022). These esul s highligh he signi ican in luence o
bo h ma ix and ea men condi ions on s a ch e og ada ion.
3.7. Techno- unc ional p ope ies
Table 4 p esen s he echno- unc ional p ope ies o lou samples
ob ained om na i e and ea ed ma ices, including wa e abso p ion
capaci y (WAC), oil abso p ion capaci y (OAC), wa e abso p ion index
(WAI), wa e solubili y index (WSI), emulsion ac i i y (EA), and emul-
sion s abili y (ES). The ma ix, ype o ea men , and hei in e ac ion
signi ican ly a ec ed all he echno- unc ional p ope ies (p <0.001).
The WAC o he lou s inc eased signi ican ly a e he MWT o all
Fig. 3. Scanning elec on mic oscopy (SEM) images o un ea ed-na i e g ain (UN), mic owa e- ea ed g ain (TG), and mic owa e- ea ed lou (TF) o ama an h
(A), buckwhea (B), quinoa (Q), and so ghum (S) a a magni ica ion o 6000×.
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
7
he ma ices, indica ing a g ea e a ini y o wa e . WAC showed a
highe inc ease when he ea men was pe o med on g ains, wi h
ama an h exhibi ing he mos no able change. The WAC o ama an h
inc eased by 26% and 63% o TF-A and TG-A, espec i ely, compa ed
wi h ha o UN-A. The highe hyd ophilici y o lou obse ed ollowing
MWT has been epo ed o be a esul o he dis up ion o cell walls and
memb anes (An e al., 2023), dis up ion o hyd ogen bonds be ween he
amo phous and c ys alline egions o s a ch (Solaesa e al., 2021), o -
ma ion o a mo e po ous s uc u e, and inc ease in hyd ophilic si es o
p o ein due o i s un olding/dissocia ion (Khe o e al., 2022). Solaesa
e al. (2021) obse ed a ela ionship be ween ea men a highe MC
and an inc ease in he WAC o mic owa ed ice lou s. The e o e, he
highe impac o he ea men on g ains could be explained by he
highe wa e e en ion wi hin he s a ch g anules du ing he ea men .
The OAC o he lou s showed no signi ican di e ences when ea men
was pe o med on ama an h and quinoa. Howe e , signi ican di e -
ences we e obse ed when buckwhea and so ghum we e ea ed,
highligh ing an inc ease in OAC o 12% o TF-B and 7% o TF-S
compa ed wi h hei co esponding un ea ed lou s. P e ious s udies
ha e epo ed educ ions in OAC in mic owa e- oas ed so ghum
(Sha anaga e al., 2019) and quinoa (Khe o e al., 2022). Con e sely,
Rao e al. (2023) obse ed an inc ease in MWT mille p o ein. Addi-
ionally, An e al. (2023) ound sligh /non-signi ican a ia ions o
MWT co n lou . These p e ious esul s, in addi ion o ou indings,
indica e ha MWT has a limi ed e ec on OAC, wi h he obse ed e ec s
a ying depending on he ma ix and ea men condi ions.
Ama an h and quinoa displayed he highes WAI alues among he
na i e samples, 8.6 g/g o UN-A and 7.3 g/g o UN-Q. Following MWT,
a conside able educ ion in his pa ame e was obse ed o hese
ma ices, wi h alues eaching 5.4 g/g o TF-A and TF-Q. Howe e ,
so ghum displayed an in e se pa e n, wi h an inc ease in WAI om 6.2
o UN-S o 6.9 o TF-S. The WSI ollowed an opposi e end o ha o
WAI. Fo ama an h and quinoa, an inc ease was obse ed wi h MWT,
pa icula ly high o TF-A (+49% compa ed o UN-A) and non-
signi ican o TG-Q. Ne e heless, so ghum p esen ed a p onounced
dec ease in WSI o TF-S compa ed wi h UN-S. Buckwhea p esen ed
in e media e beha iou , wi h small a ia ions in WAI and WSI due o
MWT. Bo h inc eases and dec eases in WAI and WSI ha e been epo ed
a e MWT depending on he ma ix and ea men condi ions. The
educ ion in WAI has been a ibu ed o he s uc u al damage and long-
chain up u e o amylopec in, an inc ease in in e molecula and in a-
molecula o ces h ough hyd ogen bonding, and he o ma ion o
amylose-lipid complexes (Vicen e e al., 2023a; Zhi e al., 2022). How-
e e , he inc ease in WAI has been a ibu ed o he weakening o
in amolecula bonds be ween amylose and amylopec in molecules,
educed c ys allini y, enhanced amylose-wa e in e ac ions, and in-
e ac ions o s a ch wi h p o eins and lipids (An e al., 2023; Solaesa
e al., 2021). The di e ing composi ions and s a ch and p o ein cha -
ac e is ics, in addi ion o he a ying wa e a ailabili y du ing MWT,
may ha e led o he obse ed di e ences be ween ea men s and
ma ices, which in u n a ou ed one o ano he phenomenon and
esul ed in di e en impac s on he alues o WAI and WSI.
All lou s exhibi ed a signi ican educ ion o comple e loss o hei
emulsion p ope ies (EA and ES) ollowing MWT. The emulsion
Table 3
The mal p ope ies o lou samples ob ained om un ea ed and mic owa e- ea ed lou s and g ains.
Sample ΔH
gel
(J/g
db)
T
p-gel
(◦C) T
o-gel
(◦C) T
e-gel
(◦C) ΔH
2
1s (J/g
db)
T
p-2
1s
(◦C)
ΔH
e
(J/g
db)
T
p- e
(◦C) %DR ΔH
2
2nd (J/g
db)
T
p-2
2nd
(◦C)
UN-A 8.7 ±0.5 b 73.7 ±0.1
a
67.7 ±
0.2 a
80.6 ±
0.3 a
0.45 ±0.08
a
96.3 ±
0.4 c
0.5 ±0.1 a nd 6 ±2 a nd nd
TF-A 7.9 ±0.1
ab
75.9 ±
0.2 b
70.3 ±
0.1 b
82.0 ±
0.2 b
0.32 ±0.01
a
94.0 ±
0.1 a
0.5 ±0.1 a nd 7 ±1 a nd nd
TG-A 7.7 ±0.1 a 76.3 ±
0.2 b
70.9 ±
0.1 c
82.9 ±
0.4 b
0.37 ±0.01
a
95.6 ±
0.1 b
0.8 ±0.1 a nd 10 ±2
a
nd nd
UN-B 10.7 ±0.2
b
68.5 ±0.2
a
61.3 ±
0.2 a
75.1 ±
0.1 a
1.10 ±0.23
b
97.1 ±
0.5 a
2.1 ±0.2 a 49.4 ±0.5
a
20 ±2
a
1.5 ±0.4 b 96.0 ±
1.5 b
TF-B 8.1 ±0.1 a 70.1 ±
0.1 b
64.1 ±
0.2 b
76.5 ±
0.1 b
0.89 ±0.07
ab
96.2 ±
0.7 a
2.7 ±0.1
ab
49.6 ±1.3
a
33 ±1
ab
0.9 ±0.2 ab 91.5 ±
0.9 ab
TG-B 7.7 ±0.1 a 70.9 ±0.1
c
65.5 ±
0.1 c
76.6 ±
0.1 b
0.62 ±0.05
a
96.1 ±
0.3 a
3.4 ±0.5 b 48.3 ±1.3
a
44 ±7
b
0.4 ±0.3 a 90.9 ±
2.1 b
UN-Q 10.6 ±0.4
b
72.4 ±0.3
a
64.0 ±
0.3 a
79.9 ±
0.5 a
0.28 ±0.03 96.8 ±
0.7
1.0 ±0.1 a 47.9 ±
0.9 ab
10 ±2
a
nd nd
TF-Q 7.6 ±0.1 a 73.6 ±
0.3 b
67.1 ±
0.3 c
80.9 ±
0.2 a
nd nd 1.6 ±0.2 b 47.0 ±0.4
a
21 ±2
b
nd nd
TG-Q 8.0 ±0.3 a 73.2 ±
0.2 ab
65.9 ±
0.2 b
80.8 ±
0.2 a
nd nd 2.1 ±0.1 c 49.3 ±
0.7 b
27 ±1
c
nd nd
UN-S 10.7 ±0.6
b
70.4 ±0.1
a
63.5 ±
0.2 a
78.1 ±
0.4 a
1.12 ±0.09
b
95.3 ±
0.2 a
4.9 ±0.5 a 50.3 ±0.1
a
43 ±6
a
1.3 ±0.3 b 94.4 ±0.6
a
TF-S 8.7 ±0.5 a 73.5 ±
0.3 b
67.6 ±
0.4 c
80.8 ±
0.1 b
0.71 ±0.11
a
97.3 ±
0.4 b
6.0 ±0.2 b 50.4 ±0.1
a
69 ±2
b
1.4 ±0.1 b 94.4 ±1.1
a
TG-S 8.1 ±0.3 a 73.8 ±
0.1 b
66.7 ±
0.2 b
82.9 ±
0.5 c
0.61 ±0.01
a
97.8 ±
0.6 b
5.8 ±0.2
ab
50.5 ±0.2
a
71 ±5
b
0.7 ±0.2 a 94.8 ±0.5
a
Analysis o a iance and signi icance (p- alues)
Ma ix (F1) *** *** *** *** *** *** *** *** *** *** *
T ea men
(F2)
*** *** *** *** *** ns *** ns *** ** ns
F1 £F2 ** *** *** *** * *** * ns ** ** *
Flou s ob ained om un ea ed-na i e g ain (UN), mic owa e- ea ed g ain (TG), and mic owa e- ea ed lou (TF) o ama an h (A), buckwhea (B), quinoa (Q), and
so ghum (S). ΔH
gel
: s a ch gela inisa ion associa ed en halpy; T
p-gel
, T
o-gel
, and T
e-gel
: peak, onse , and endse empe a u es o gela inisa ion peak, espec i ely; ΔH
2
1s
and T
p-2
1s : en halpy and peak empe a u e associa ed wi h he second peak obse ed on i s scan on esh sample, espec i ely; ΔH
e
: en halpy associa ed wi h he
mel ing o ec ys allised amylopec in a e 7 days o s o age a 4 ±2 ◦C; T
p- e
: peak empe a u e o mel ing o ec ys allised amylopec in; DR: deg ee o e og ada ion;
ΔH
2
1s and T
p-2
1s : en halpy and peak empe a u e associa ed wi h he second peak obse ed on second scan on e og aded sample, espec i ely; nd: non-de ec able;
db: d y basis. Da a is exp essed as mean ±s anda d de ia ion. Signi ican s a is ical di e ences (p <0.05) a e indica ed by di e en le e s o he same pa ame e and
ma ix. Analysis o a iance and signi icance o ma ix (A,B,Q,S), ea men (UN, TG, TF), and hei in e ac ion: ***p <0.001, **p <0.01, *p <0.05, ns: non-
signi ican .
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
8
p ope ies o lou s a e highly ela ed o hei p o ein ac ion cha ac-
e is ics (Vicen e e al., 2023a). Bo h inc eases and dec eases in EA and
ES ha e been epo ed a e MWT, depending on he ma ix and he
ea men . MWT may induce pa ial un olding o p o eins, esul ing in
g ea e exposu e o hyd ophobic g oups and seconda y s uc u al
modi ica ion, which enhances p o ein abso p ion a he oil/wa e
in e ace (Rao e al., 2023; Vicen e e al., 2023a). Howe e , o mo e
in ense ea men condi ions, such as high mois u e con en , high em-
pe a u e, and/o long du a ion, as hose in ou s udy, he abili y o he
p o ein o o m and s abilise emulsions may be educed by hea -induced
dena u a ion and agg ega ion, esul ing in he o ma ion o la ge p o-
ein agg ega es ha a e unable o s abilise he oil/wa e in e ace (Khe o
e al., 2022; Vicen e e al., 2023b).
4. Conclusions
The ou comes o his s udy indica e ha he e icacy o MWT in
modi ying he p ope ies o a ma ix is g ea ly in luenced by he
bo anical o igin o he ea ed sys em and i s o m du ing ea men ,
whe he i is in lou o g ain o m. The MWT p o ed e ec i e in
changing he mic os uc u e, he mal p ope ies, and echno- unc ional
p ope ies o he esul ing lou s. All na i e samples displayed compa-
able mic owa e abso p ion capaci ies, wi h wa e being he only sig-
ni ican abso be in he s udied ma ices. This was co obo a ed by he
obse a ion ha equi alen empe a u e cu es we e ob ained when
di e en samples we e subjec ed o he same ea men condi ions, wi h
he same mic owa e e ec i e ime being equi ed. Howe e , signi ican
di e ences we e obse ed in he mobili y o wa e du ing hea ing. The
a e o wa e loss du ing hea ing was ema kably highe in he lou s,
wi h he g ains exhibi ing signi ican di e ences depending on he
ma ix. The e o e, he obse ed di e ences in lou mic os uc u e,
he mal p ope ies, and echno- unc ional p ope ies may be a ibu ed
no only o he di e en ma ix composi ions bu also o he di e en
dis ibu ion and mobili y o wa e wi hin he g ains du ing MWT.
Mo eo e , his s udy e ealed ha he selec ion o he ma ix o m
(g ain o lou ) subjec ed o ea men may po en ia e a speci ic p op-
e y, he eby enabling he p oduc ion o a wide ange o modi ied lou s
wi h adap ed unc ionali y. Fo ins ance, g ain ea men was ound o
be e ec i e in mi iga ing he e iden di e ence in colou associa ed
wi h lou ea men , while simul aneously enhancing he wa e ab-
so p ion capaci y o he lou . Addi ional esea ch is s ill equi ed o
cla i y he molecula /s uc u al basis o he dis inc impac s o he MWT
on ma ices o a ying sou ces and o ms, wi h a pa icula ocus on he
ela ionship be ween s uc u e and unc ion in mic owa e modi ica ion.
CRediT au ho ship con ibu ion s a emen
Ainhoa Vicen e: W i ing – e iew & edi ing, W i ing – o iginal
d a , Visualiza ion, Me hodology, In es iga ion, Fo mal analysis,
Concep ualiza ion. Ma ina Villanue a: W i ing – e iew & edi ing,
Visualiza ion, Valida ion, Me hodology, Concep ualiza ion. Jose Ma ía
Mu˜
noz: W i ing – e iew & edi ing, So wa e, Me hodology, Fo mal
analysis, Concep ualiza ion. Ped o A. Caballe o: W i ing – e iew &
edi ing, Supe ision, Resou ces, Concep ualiza ion. Felicidad Ronda:
W i ing – e iew & edi ing, Valida ion, Supe ision, Resou ces, P ojec
adminis a ion, Me hodology, Funding acquisi ion, Concep ualiza ion.
Decla a ion o compe ing in e es
The au ho s con i m ha hey ha e no con lic s o in e es wi h
espec o he wo k desc ibed in his manusc ip .
Da a a ailabili y
Da a will be made a ailable on eques .
Acknowledgemen s
The au ho s hank he Spanish Minis e io de Ciencia e Inno aci´
on
(PID2019-110809RB-I00 and EQC2021-006985-P), Minis e io de Cien-
cia, Inno aci´
on y Uni e sidades (PID2023-153330OB-I00), and he
Jun a de Cas illa y Le´
on/FEDER (VA195P20 and CLU 2019–04 – BIO-
ECOUVA Uni o Excellence o he Uni e si y o Valladolid) o hei
inancial suppo . A. Vicen e hanks he Spanish Minis e io de Ciencia,
Inno aci´
on y Uni e sidades o he FPU doc o a e g an . The au ho s
hank Joanna Ha asym o assis ing wi h he supply o buckwhea g ain.
Appendix A. Supplemen a y da a
Supplemen a y da a o his a icle can be ound online a h ps://doi.
o g/10.1016/j. oodhyd.2024.110680.
Re e ences
AACC. (2010). App o ed me hods o analysis. Ce eals & g ains associa ion (11 h ed.).
Abebe, W., Colla , C., & Ronda, F. (2015). Impac o a ie y ype and pa icle size
dis ibu ion on s a ch enzyma ic hyd olysis and unc ional p ope ies o e lou s.
Ca bohyd a e Polyme s, 115, 260–268. h ps://doi.o g/10.1016/j.
ca bpol.2014.08.080
Al a ez-Jube e, L., A end , E. K., & Gallaghe , E. (2010). Nu i i e alue o pseudoce eals
and hei inc easing use as unc ional glu en- ee ing edien s. T ends in Food Science
and Technology, 21(2), 106–113. h ps://doi.o g/10.1016/j. i s.2009.10.014
Table 4
Techno- unc ional p ope ies o lou samples ob ained om un ea ed and
mic owa e- ea ed lou s and g ains.
Sample WAC
(g/g)
OAC (g/
g)
WAI
(g/g)
WSI (g/
100g)
EA (%) ES (%)
UN-A 1.20 ±
0.03 a
1.13 ±
0.01 ab
8.6 ±
0.1 c
5.3 ±
0.2 a
54.5 ±
0.4 c
50.9 ±
2.3 b
TF-A 1.51 ±
0.02 b
1.15 ±
0.02 b
5.4 ±
0.2 a
7.8 ±
0.3 c
<0.1 a –
TG-A 1.96 ±
0.04 c
1.11 ±
0.02 a
6.5 ±
0.3 b
5.8 ±
0.2 b
12.1 ±
0.1 b
6.4 ±
1.8 a
UN-B 1.14 ±
0.02 a
0.97 ±
0.01 a
6.8 ±
0.2 b
4.2 ±
0.1 b
58.6 ±
0.6 c
34.8 ±
0.8 c
TF-B 1.67 ±
0.04 b
1.08 ±
0.01 c
6.8 ±
0.1 b
3.9 ±
0.2 a
9.5 ±
0.7 b
6.1 ±
0.5 b
TG-B 1.70 ±
0.04 b
1.01 ±
0.01 b
6.3 ±
0.1 a
4.5 ±
0.1 c
7.1 ±
0.9 a
3.7 ±
0.8 a
UN-Q 1.09 ±
0.01 a
1.09 ±
0.02 a
7.3 ±
0.2 b
5.1 ±
0.2 a
52.6 ±
0.3 c
44.9 ±
0.5 b
TF-Q 1.84 ±
0.04 b
1.10 ±
0.02 a
5.4 ±
0.3 a
5.8 ±
0.3 b
<0.1 a –
TG-Q 1.92 ±
0.02 c
1.11 ±
0.01 a
5.5 ±
0.3 a
5.2 ±
0.1 a
8.5 ±
0.3 b
4.7 ±
0.4 a
UN-S 1.34 ±
0.02 a
1.05 ±
0.01 b
6.2 ±
0.2 a
3.7 ±
0.1 b
39.3 ±
1.4 b
8.6 ±
0.5
TF-S 1.62 ±
0.03 b
1.12 ±
0.01 c
6.9 ±
0.1 b
2.1 ±
0.1 a
<0.1 a –
TG-S 1.73 ±
0.02 c
1.02 ±
0.02 a
6.2 ±
0.2 a
3.5 ±
0.1 b
<0.1 a –
Analysis o a iance and signi icance (p- alues)
Ma ix (F1) *** *** *** *** *** ***
T ea men
(F2)
*** *** *** *** *** ***
F1 £F2 *** *** *** *** *** ***
Flou s ob ained om un ea ed-na i e g ain (UN), mic owa e- ea ed g ain
(TG), and mic owa e- ea ed lou (TF) o ama an h (A), buckwhea (B), quinoa
(Q), and so ghum (S). WAC: wa e abso p ion capaci y, OAC: oil abso p ion
capaci y, WAI: wa e abso p ion index, WSI: wa e solubili y index, EA: emul-
si ying ac i i y, ES: emulsion s abili y. Da a is exp essed as mean ±s anda d
de ia ion. Signi ican s a is ical di e ences (p <0.05) a e indica ed by di e en
le e s o he same pa ame e and ma ix. Analysis o a iance and signi icance
o ma ix (A,B,Q,S), ea men (UN, TG, TF), and hei in e ac ion: ***p <0.001,
**p <0.01, *p <0.05, ns: non-signi ican .
A. Vicen e e al.
Food Hyd ocolloids 159 (2025) 110680
9
