Key words: extruded, snack, gelatinization, discarded avocados, proximal analysis

Transcription

1 Proceedings VI World Avocdo Congress (Acts VI Congreso Mundil del Agucte) Viñ Del Mr, Chile Nov ISBN No USE OF HASS AVOCADO (Perse mericn Mill.) SEED AS A PROCESSED PRODUCT J. A. Olet 1, M. Schwrtz 2., P. Undurrg 1 nd S. Contrers 3 1 Fcultd de Agronomí. Pontifici Universidd Ctólic de Vlpríso. Sn Frncisco s/n L Plm Quillot. Chile. Emil: jolet@ucv.cl 2 Fcultd de Ciencis Agrris y Forestles Universidd de Chile. Snt Ros L Pintn 3 INTEC-CHILE Avocdo seeds re wste product in the pulp nd oil production nd represent, in Hss, out 12% of the fruit weight. In this study product ws developed tht cn e used s snck. Ripe vocdo fruits with 11% oil content were deseeded, nd the seeds were dried nd milled. This milled powder ws evluted, ccording to its percentges of: dry mtter, totl solids, lipids, protein, sh fire, totl crohydrtes nd clories 100g -1. Then the dry smple ws split into two prts. The first prt ws lended with milled corn t 40-60% (vocdo-corn). The second prt ws tken s control nd ws not mixed. Both tretments were treted in Wenger X 20 single screw extrusion system. The otined product ws compred with commercil snck. The yield ws 8.4 % nd the ppernce nd dhesion were good. The results re showing product with wter content of 8%, density g L -1, wter sorption index 6.89 g g -1, soluility in wter 4.69 g 100g -1, geltiniztion 95.25%. The finl product showed low levels of trypsin inhiitors. Key words: extruded, snck, geltiniztion, discrded vocdos, proximl nlysis UTILIZACIÓN DE LA SEMILLA DE PALTA (Perse mericn Mill.) CV. HASS COMO PRODUCTO AGROINDUSTRIAL J. A. Olet 1, M. Schwrtz 2., P. Undurrg 1 y S. Contrers 3 1 Fcultd de Agronomí. Pontifici Universidd Ctólic de Vlpríso. Sn Frncisco s/n L Plm Quillot. Chile. Correo electrónico: jolet@ucv.cl 2 Fcultd de Ciencis Agrris y Forestles Universidd de Chile. Snt Ros L Pintn 3 INTEC-CHILE L semill de plt en l ctulidd constituye un descrte de los procesos de elorción de pulps y de ceite, constituyendo en el cv Hss lrededor del 12% del peso del fruto. En el presente estudio se desrrolló, con semill del cv Hss, un producto extruído, posile de ser consumido como snck. Pr ello, plts mdurs con más de 11% de ceite se les extrjo l semill y ést se secó y se molió. A est semill molid se le determinó porcentje de humedd, sólidos, lípidos, proteíns, cenizs, fir, crohidrtos y clorís 100 g -1. Luego l muestr sec 1

2 fue dividid en dos prtes. L primer fue mezcld con míz molido, en proporción de 40-60% (plt-míz) y l segund, testigo, no fue mezcld. Amos trtmientos fueron sometidos un extrusor Wenger X20 de tornillo, donde se otuvo un producto extruído, el cul fue comprdo con un snck comercil. El rendimiento otenido fue de 8,4% y se otuvo pr mos trtmientos un extruído de uen prienci y grdo de dhesión. Los resultdos muestrn que el producto tuvo los siguientes prámetros: Humedd 8%; Densidd 212,5 g L -1, Índice sorción gu 6,89 g g -1, Índice soluilidd en gu 4,69 g 100g -1, Geltinizción 95,25 %. Los extruídos de semill otenidos presentron jos niveles de inhiidores de tripsins. Plrs clve: extruido, snck, geltinizción, descrtes de plt, nálisis proximl 1. Introduction Once the edile pulp is seprted, the skin nd seed re left s residues. The seed hs lower lipid content thn pulp; therefore, lipids re not considered importnt in processes such s the otining of oil. However, Mzlik (1965) nd Lee (1981) found tht the ftty cids in the seed hve higher levels of polyunsturted cids thn in the pulp. In ddition, enzymes nd sustnces with ntiiotic nd ntimicroil chrcteristics my e found in the stone. The ltter would hve possile use in cnned mets, curing processes nd in the preservtion of confectionery crems. The seed my e lso used to extrct tnnins nd pigments. Furthermore, vocdo stones my hve some compounds tht void the rowning of the fruit (Cnto, 1980). Khn (1987) sttes tht vocdos seeds re potentil strch source due to their content round 30%. He lso mentions tht the microscopic evlution of this element showed the presence of chrcteristics similr to those of corn. The prmeters of geltiniztion nd viscosity re from type C (restricted diltion), which suggests their possile use in food tht must e heted up t 100 C (212 F), such s soups nd suces. The vocdo seeds hve some nti-nutritionl chrcteristics such s hydrocynic cid, cynogenic glycosides, condensed polyphenols nd some tnnins, which could ct dversely on their possile use. However, the gret mjority of those sustnces re thermolile; therefore, suitle het tretment (cooking) would destroy them (OAS, 1978; Deshpnde nd Slunke, 1982; Schmdit nd Heel, 1986). Studies on the ntimicroil ility of n extrct in vocdo seed cetone determined tht it hs n nticteril effect on S. ureus, B. sutillis, Aspergillus glucus nd Penicillium notrum, ut it did not show ny effects on E. coli nd Pseudomons fluorescens (Neemn, 1970). 2

3 The use of vocdo seed to elorte n extruded product to e used s sncks my e wy out to the discrds generted in the industrilistion of vocdos. In the present tril, the chemicl chrcteristics of seeds from Hss nd Fuerte vocdos hrvested on two mturity stges were evluted, determining the qulity of product extruded of Hss vocdo seed compring it with commercil snck. 2. Mterils nd methods At the Experimentl Sttion L Plm of the Fculty of Agriculturl Sciences, Pontifici Universidd Ctólic de Vlpríso, locted in the city of Quillot (Ltitude S, Longitude W), 20 kg of Fuerte vocdo nd 100 kg of Hss vocdos were hrvested. In oth vrieties, unripe fruit ws hrvested; 10 kg of Fuerte vriety with 3.23% oil nd 10 kg of Hss vriety with 5.1% oil; nd fruit designted s ripe, 10 kg of Fuerte cultivr with 13% oil nd 90 kg of Hss vriety with 19.5% oil. From ech cultivr nd on ech mturity stge, the seeds were otined (2 kg of Fuerte vriety for ech mturity stge; 1 kg of unripe Hss vocdos nd 15 kg of ripe Hss vocdos); these seeds were wshed with wter. From these seeds, 1-kg smples of ech mturity stge nd vriety were tken, using them for the mesuring of proximl nlysis. For the chrcteristion of seeds from ech vriety nd mturity stge, proximl nlysis ws conducted, determining the following prmeters: % moisture (A.O.A.C., 1980); % Proteins (Kjeldhl method; % nitrogen x 6.25) (A.O.A.C., 1980); % shes (A.O.A.C., 1980); % ether extrct (totl lipids) (A.O.A.C., 1980); % nitrogen-free extrct (totl crohydrtes) (A.O.A.C., 1980); nd % fire (A.O.A.C., 1980). For the mnufcturing of n extruded product, only ripe seeds from Hss vrieties were used. The remining 14 kg of seeds from the previous mesuring were dried for 2 to 3 hours through drying mchine t 65 C (149 F). Susequently, they were grinded nd milled in grinding mill, generting grnulted product, whose drying ws finished in drying mchine t 65 C until reching 15% moisture. The percentge of strch from these milled nd dried seeds ws determined (A.O.A.C, 1980). For the extrusion of stones, two processing tests were conducted: the first one with mixture of seed nd corn in proportion of 40% - 60%; the second one with 100% seed of dried nd milled vocdo. In oth cses, totl mount of 10 kg ws used, size of nominl lower limit smple for the good opertion of extruder. The loss of mteril in the equipment does not exceed 5%. An equipment of pilot extrusion of the rnd Wenger X20 ws used; nd the extrusion conditions re shown in Tle 1. 3

4 According to the results of the previous processing, it ws determined tht the stone moisture decresed from n verge of 50% to 6% fter the drying process. This mens tht pproximtely 0.5 kg of milled stone cn e otined from ech kilogrm of fresh stone. Tle 1: Conditions of extrusion opertion of vocdo seed Prmeter 40/60% vocdo - 100% seed corn vocdo Vriety Hss Hss Initil weight of fresh stone (kg) 8 20 Drying conditions 2-3 h C 2-3 h C Product to e processed (kg) 4 10 Corn dded (kg) 6 0 Moisture of dried milled stone (%) 6 6 Conditions of the extrusion Process time 5 minutes 5 minutes Die Conicl 2 perfortions 4 mm dimeter Conicl 2 perfortions 4 mm dimeter Numer of cutters 7 4 Speed of cutters Position 7 Position 7 RPM screw Position 2 (394 RPM) Position 2 (394 RPM) Feed Position 6 Position 7 Pre-conditioner Position 7 Position 4,5 Numer of jckets 3 (with wter) 2 (with wter) Temperture lst jcket 70 C 90 C Pre-conditioner rotmeter 10 m 3 /s 25 m 3 /s Jcket rotmeter 15 m 3 /s 30 m 3 /s Estimted losses 5 % 5 % The qulity of the vocdo-extruded product otined ws lso compred with commercil product. In ddition, the existence of nti-nutritionl chrcteristics, trypsin inhiitors nd tnnin content (polyphenols) ws determined in seeds of Hss vocdos, in the milled nd dried seed s well s in the extruded product to verify the presence nd their thermolility with the extrusion process. A microiologicl nlysis ws lso conducted. 3. Results nd discussion 4

5 Proximl nlysis of seeds from Fuerte nd Hss vocdos on two mturity stges The results otined for ech verge prmeter in oth vrieties re illustrted in Figures 1 nd 2. Hss - Unripe Hss Ripe Percentge % Proteins (%NT * 6.25) %Ether E. % Ashes % Fires % N.F.E. % Moisture Hss - Unripe Hss - Ripe *The sme letters in ech prmeter do not show ny significnt differences ccording to Tukey Test p Figure 1: Percentge evolution of protein, ether extrct, shes, nitrogen-free extrct nd moisture in stones of Hss vocdo. Fuerte - Unripe Fuerte - Ripe Percentge % Proteins (%NT * 6.25) % Ether E % Ashes % Fires % N.F.E. % Moisture Fuerte - Unripe Fuerte - Ripe *The sme letters in ech prmeter do not show ny significnt differences ccording to Tukey Test p Figure 2: Percentge evolution of protein, ether extrct, shes, nitrogen-free extrct nd moisture in stones of Fuerte vocdo. Regrding the percentge of proteins, it my e oserved tht this is higher in those seeds coming from ripe vocdos. When compring the vrieties, the Hss seeds showed higher level of proteins thn the Fuerte seeds. In the mesurement of Ether Extrct (mesurement of ftty mtter), it my e noticed tht the Hss vriety shows higher level of ftty mtter thn tht coming 5

6 from Fuerte. In ddition, in oth vrieties, the seed coming from ripe fruits hd higher level of ft mtter, ecuse of the energy tht the seed needs for its germintion. This sitution cuses tht seeds coming from ripe vocdos would e more likely to suffer rncidity nd possily e ffected y higher oxidtion cpcity, especilly in the formtion of drk melnoid compounds. The fire percentge of seeds incresed in riper fruits; however, it hd higher rte in Hss vriety thn in Fuerte. When nlysing the percentge of shes, different ehviour my e noticed etween these vrieties. In Hss vriety, the sh percentge ws higher in ripe fruits, unlike Fuerte vriety. Regrding the Nitrogen-Free Extrct (crohydrtes), the mturity stge of the fruits nd the cultivr lso ffected its level. Seeds from riper fruits hd higher level of crohydrtes, ecuse the seed is structure tht needs energy during germintion. When considering tht gret percentge of crohydrtes in the vocdo seed re constituted y strch, the Hss cultivr is regrded s the est option to chieve good qulity of extrusion. In regrd to moisture, this decreses s the fruit ripened. This is cused y the increse of nutrients previously nlysed. Snck Mnufcturing The strch nlysis of Hss vocdo seed determined content of 41.3%. This nlysis fits in with the dt otined from iliogrphy, where percentge round 30% on wet sis is estimted to e used for extrusion. The chrcteristics of extruded products otined re shown in Tle 2. Tle 2: Moisture (%), Density (g/l), wter sorption rte (g/g), rte of soluility in wter (g/100g) nd Geltinistion (%) of two products extrcted on sis of vocdo seed nd commercil product. Prmeter 40/60% (Avocdo/Corn) 100% Avocdo Commercil snck product Moisture (%) Density (g/l) Wter sorption 6.89 rte (g/g) Rte of soluility in wter (g/100g) Geltinistion (%) According to the dt otined, for every 100 kg of vocdo, round 16.5 kg of fresh stones my e generted, nd from these, fter processing, round 8.8 kg 6

7 of dried milled stone is otined. The extrusion hd efficiency round 95%, eventully otining 8.4 kg of extruded product. Regrding the extrusion conditions for the two trils conducted, no prolems of excess of product stuck on the equipment were detected, ut opertion with higher tempertures ws necessry when working only with stones. In the extrusion of stone lone, type of snck product, less swollen thn the product mixed with corn, is otined. If pressure is pplied, this stone snck is disintegrted more esily thn the mteril, resulting in powder. This my e cused y lower moisture content of the product lone compred with tht mixed with corn. When compring the product otined with 100% of vocdo seeds with commercil snck, it is oserved tht this showed chrcteristics very similr to the commercil product, except for its higher density. Menwhile, the stone/corn extrusion in proportion of 40/60% showed results out of the limits mentioned nd would require susequent drying to reduce its moisture levels to more stle vlues, lthough its geltinistion percentge flls into norml figures. The result of the microiologicl nd nti-nutritionl nlyses is shown in Tle 3. The microiologicl nlyses showed vlues of low totl count of cteri for oth products. In the evlution of nti-nutritionl fctors, the presence of oth sustnces in the powder product ws detected efore eing extruded, ut in concentrtions out 10 times lower thn those normlly seen in legumes. The results clerly indicte tht the extrusion is medium to destroy such sustnces or reduce them to minimum levels, due to the het tretment estlished in the opertion. Tle 3: Anti-nutritionl fctors nd microiologicl qulity of dried nd milled vocdo seed nd vocdo seed extrusion: 40/60% (vocdo/corn) nd 100% vocdo. Prmeter Dried milled Extrusion 40/60% Extrusion seed (Avocdo/Corn) 100% Avocdo Moisture (%) Trypsin inhiitors (UTI /g smple) Tnnins (gr/100gr) 0.1 < Totl count (UFC/g)

8 4. Conclusions The levels of proteins in Fuerte nd Hss vocdos re higher in ripe fruits. The Hss stones showed strch content ove 30%. It is possile to otin from the Hss vocdo stones snck lone or comined with corn with low totl count of cteri. The extrusion is medium to destroy trypsin inhiitors nd tnnins or to reduce them to minimum levels, in vocdo seed. However, this requires n extr drying. The Hss vocdo seed provides good qulity to the product otined 5. References A.O.A.C, Officil Methods of Anlysis, 13 th Anlyticl Chemists. Wshington D.C ed. Assocition of Officil Cnto, W.; Sntos, L. y Trvglini, M Óleo de cte: extrção, usos e seus mercdos tuis no Brsil e n Europ. Estudos. Econômicos. Cmpins: ITAL, p. (Alimentos Processdos, 11) Deshpnde, S. nd D. Slunke Interction of tnnic cid nd ctechin with legume strches. Journl Food Science 47: Khn, V Chrcteriztion of Strch Isolted from Avocdo Seeds. Journl of Food Science 52 (6): Kshmn, Y.; Neemn, I.; nd Lifshitz, A New compounds from vocdo per-ii. Tetrhedron 26: Lee, S Methods for percent oil nlysis of vocdo fruit. Clif. Avoc.Soc.Yer. 65: Mzlik, P Les lipides de l voct (Perse mericn vr. Fuerte). I. Composition en cides grs des diverses prties du fruit. Fruits. 20: Neemn, I.; Lifstritz, A. nd Kshmn, Y New. nticteril gent isolted from the vocdo per. Appl. Microiol. 19: Schmidt-Heel, H Tóxicos químicos en los limentos. Avnces en su identificción, previsión y desintoxicción. 82 p. Fundción Chile, Sntigo, Chile. 8