12 research outputs found
Millora de la qualitat sensorial i nutricional de les varietats tradicionals hortĂcoles: el cas del calçot (Allium cepa L.)
Sensory and nutritional quality are key elements for consumers, providing added value to agri-food products. However, there is a general perception that horticultural products have lost their quality, especially their taste.
Landraces have an identity associated with a specific area and historical origin, and are adapted to local conditions, both environmental (soil and climate) and crop management (generally low inputs). Nevertheless, they present a medium-low yield, resulting in a progressive replacement by improved varieties with high yields when cultivated in high-input systems. The landraces that remain in commerce are those which have found a high-quality niche market where consumersâ interests go beyond the price. The survival of landraces depends on their distinctive qualities, as in the case of calçots (the immature floral stems of second-year sprouts of onions (Allium cepa L.)). Calçots are typical of Catalonia, specifically from counties in the province of Tarragona where the European Union has designated them with the Protected Geographical Indication (PGI): Calçot de Valls. The calçot market is in constant evolution and expansion, and its cultivation extended beyond its traditional area many years ago.
The quality attributed to a product should be objective and measurable, in order to make its control a routine. The determination of food sensory and nutritional qualities (the most relevant qualities for consumers) presents some limitations, especially when a large number of samples needs to be tested. This necessitates the search for alternative methodologies to measure food quality in the fastest and most efficient way. For example, NIR (Near Infrared) spectroscopy presents some advantages in comparison with conventional analytical methods: multi-analyte, speed, low cost, no reagents, etc.
The objective of this thesis, structured around four articles, is to develop knowledge and tools to improve and control the nutritional and sensory qualities of calçots, with the aim of providing an identification based on those two characteristics in the Calçot de Valls.
Nutritional properties of calçots are similar to those previously reported in onion bulbs, despite the fact that the part of the plant consumed is different. As happens with other vegetables, the cooking process has an important impact on the calçotsâ composition, increasing most of the parameters tested, and decreasing others like total phenols or, more drastically, flavonoids, with an 85% loss.
The environmental influence was found to be higher than genetic influence when only considering accessions from the Blanca Tardana de Lleida onion landrace (the only one authorized by the PGI). This result suggests to prioritize management optimization over plant breeding programs to increase quality. However, when considering three other onion varieties, the genetic variability sharply increases, as do the expected advances in plant breeding introducing new variability via cross-breeds between varieties.
It would be feasible to use NIR spectroscopy to test the nutritional and sensory properties of calçots, while facilitating the management of a large number of samples. The accuracy of models developed to estimate chemical properties was between good and excellent (RPD (Ratio of Performance to Deviation) between 1.99 and 8.07). Although the developed models to estimate sensory attributes are less accurate (RPD between 1.41 and 1.78), NIR spectroscopy can help to detect those samples that differ substantially from the ideotype (high sweetness, low fiber perception and the absence of off-flavors), as a first screening in plant breeding programs or in the elimination of outliers in quality control.La qualitat sensorial i nutricional sĂłn aspectes importants per al consumidor actual i donen valor afegit als productes agroalimentaris. Hi ha però, una percepciĂł generalitzada que la qualitat, especialment el gust, dels productes hortofructĂcoles sâha anat deteriorant. Les varietats tradicionals tenen una identitat reconeguda associada a una localitzaciĂł especĂfica i un origen històric, amb una bona adaptaciĂł a condicions locals (tant a les edafoclimĂ tiques, com als sistemes tradicionals de cultiu, que solen ser de baixos inputs). Aquestes tenen però, un rendiment mitjĂ -baix, el que ha provocat la seva progressiva substituciĂł per varietats millorades, molt mĂŠs productives en cultius amb elevats inputs. Per això, la majoria de les varietats tradicionals que romanen en el comerç sĂłn aquelles que han trobat un nĂnxol de mercat amb demandes de caracterĂstiques especials, mes enllĂ del preu. La seva supervivència passa doncs per tenir qualitats distintives, com ĂŠs el cas dels calçots (tiges florals immadures de la ceba (Allium cepa L.)). Els calçots sĂłn un cultiu tĂpic de Catalunya, en concret de les comarques de Tarragona, on hi tenen atorgada una marca de qualitat europea: la IndicaciĂł GeogrĂ fica Protegida (IGP) Calçot de Valls. El mercat del calçot estĂ en constant evoluciĂł i expansiĂł, i fa anys que la seva producciĂł sâha estès tambĂŠ fora de la zona tradicional del cultiu. La qualitat que sâatribueix a un producte, hauria de ser objectiva i mesurable, per poder convertir el seu control en rutinari. La determinaciĂł del valor sensorial i nutricional dels aliments (dues de les qualitats mĂŠs rellevants pels consumidors) presenta però una sèrie de limitacions, en especial quan el nombre de mostres a avaluar ĂŠs elevat. Això fa necessari buscar mètodes alternatius que permetin quantificar la qualitat de manera mĂŠs rĂ pida i eficient. Per exemple, lâespectroscòpia dâinfraroig proper (NIR, Near Infrared) presenta avantatges en comparaciĂł amb els mètodes analĂtics convencionals: multi-analit, rapidesa, baix cost, sense reactius, etc. Amb la finalitat que el Calçot de Valls es pugui identificar tant per les seves caracterĂstiques sensorials com nutricionals, aquesta tesi, estructurada en quatre articles, tĂŠ lâobjectiu de desenvolupar coneixement i eines per a la millora i control dâaquestes dues qualitats en els calçots. Les caracterĂstiques nutricionals del calçot han resultat ser similars a les descrites en ceba, malgrat la part que sâaprofita de la planta sigui diferent. Com passa amb altres vegetals, la cocciĂł tĂŠ un fort impacte sobre la composiciĂł del calçot, incrementant el contingut de molts dels compostos estudiats, però disminuint dâaltres com els fenols totals o, de manera drĂ stica, els flavonoides amb una pèrdua dâun 85%. La variabilitat fenotĂpica atribuĂŻble a lâambient ha estat superior a la genètica dins del tipus varietal ceba Blanca Tardana de Lleida (lâĂşnica autoritzada per la IGP). Això suggereix prioritzar la millora del maneig a la millora genètica intra-varietal si es vol incrementar la qualitat. No obstant, si considerem tres altres varietats de ceba, la variabilitat genètica sâamplia molt i, per tant, tambĂŠ les possibilitats de fer millora introduint nova variabilitat a travĂŠs dâencreuaments. Lâespectroscòpia NIR sâha mostrat com una alternativa viable en lâavaluaciĂł de la qualitat nutricional i sensorial del calçot, facilitant lâanĂ lisi dâun nombre elevat de mostres. Per a els carĂ cters quĂmics el nivell de predicciĂł dels models ha estat entre bona i excel¡lent (RPD (Ratio of Performance to Deviation) entre 1,99 i 8,07). Pel que fa a la predicciĂł de carĂ cters sensorials, malgrat els models desenvolupats presenten un nivell de predicciĂł inferior (RPD entre 1,41 i 1,78), aquets sĂłn capaços de discernir les mostres que mĂŠs sâallunyen de lâidiotip establert (dolçor elevada, baixa fibrositat i absència de gustos estranys) facilitant un primer cribatge en millora, o eliminaciĂł de fora-tipus en el control de qualitat
Millora de la qualitat sensorial i nutricional de les varietats tradicionals hortĂcoles: el cas del calçot (Allium cepa L.)
Tesi amb diferents seccions retallades per drets de l'editorPremi Extraordinari de Doctorat, promociĂł 2018-2019. Ămbit de CiènciesSensory and nutritional quality are key elements for consumers, providing added value to agri-food products. However, there is a general perception that horticultural products have lost their quality, especially their taste.
Landraces have an identity associated with a specific area and historical origin, and are adapted to local conditions, both environmental (soil and climate) and crop management (generally low inputs). Nevertheless, they present a medium-low yield, resulting in a progressive replacement by improved varieties with high yields when cultivated in high-input systems. The landraces that remain in commerce are those which have found a high-quality niche market where consumersâ interests go beyond the price. The survival of landraces depends on their distinctive qualities, as in the case of calçots (the immature floral stems of second-year sprouts of onions (Allium cepa L.)). Calçots are typical of Catalonia, specifically from counties in the province of Tarragona where the European Union has designated them with the Protected Geographical Indication (PGI): Calçot de Valls. The calçot market is in constant evolution and expansion, and its cultivation extended beyond its traditional area many years ago.
The quality attributed to a product should be objective and measurable, in order to make its control a routine. The determination of food sensory and nutritional qualities (the most relevant qualities for consumers) presents some limitations, especially when a large number of samples needs to be tested. This necessitates the search for alternative methodologies to measure food quality in the fastest and most efficient way. For example, NIR (Near Infrared) spectroscopy presents some advantages in comparison with conventional analytical methods: multi-analyte, speed, low cost, no reagents, etc.
The objective of this thesis, structured around four articles, is to develop knowledge and tools to improve and control the nutritional and sensory qualities of calçots, with the aim of providing an identification based on those two characteristics in the Calçot de Valls.
Nutritional properties of calçots are similar to those previously reported in onion bulbs, despite the fact that the part of the plant consumed is different. As happens with other vegetables, the cooking process has an important impact on the calçotsâ composition, increasing most of the parameters tested, and decreasing others like total phenols or, more drastically, flavonoids, with an 85% loss.
The environmental influence was found to be higher than genetic influence when only considering accessions from the Blanca Tardana de Lleida onion landrace (the only one authorized by the PGI). This result suggests to prioritize management optimization over plant breeding programs to increase quality. However, when considering three other onion varieties, the genetic variability sharply increases, as do the expected advances in plant breeding introducing new variability via cross-breeds between varieties.
It would be feasible to use NIR spectroscopy to test the nutritional and sensory properties of calçots, while facilitating the management of a large number of samples. The accuracy of models developed to estimate chemical properties was between good and excellent (RPD (Ratio of Performance to Deviation) between 1.99 and 8.07). Although the developed models to estimate sensory attributes are less accurate (RPD between 1.41 and 1.78), NIR spectroscopy can help to detect those samples that differ substantially from the ideotype (high sweetness, low fiber perception and the absence of off-flavors), as a first screening in plant breeding programs or in the elimination of outliers in quality control.La qualitat sensorial i nutricional sĂłn aspectes importants per al consumidor actual i donen valor afegit als productes agroalimentaris. Hi ha però, una percepciĂł generalitzada que la qualitat, especialment el gust, dels productes hortofructĂcoles sâha anat deteriorant. Les varietats tradicionals tenen una identitat reconeguda associada a una localitzaciĂł especĂfica i un origen històric, amb una bona adaptaciĂł a condicions locals (tant a les edafoclimĂ tiques, com als sistemes tradicionals de cultiu, que solen ser de baixos inputs). Aquestes tenen però, un rendiment mitjĂ -baix, el que ha provocat la seva progressiva substituciĂł per varietats millorades, molt mĂŠs productives en cultius amb elevats inputs. Per això, la majoria de les varietats tradicionals que romanen en el comerç sĂłn aquelles que han trobat un nĂnxol de mercat amb demandes de caracterĂstiques especials, mes enllĂ del preu. La seva supervivència passa doncs per tenir qualitats distintives, com ĂŠs el cas dels calçots (tiges florals immadures de la ceba (Allium cepa L.)). Els calçots sĂłn un cultiu tĂpic de Catalunya, en concret de les comarques de Tarragona, on hi tenen atorgada una marca de qualitat europea: la IndicaciĂł GeogrĂ fica Protegida (IGP) Calçot de Valls. El mercat del calçot estĂ en constant evoluciĂł i expansiĂł, i fa anys que la seva producciĂł sâha estès tambĂŠ fora de la zona tradicional del cultiu. La qualitat que sâatribueix a un producte, hauria de ser objectiva i mesurable, per poder convertir el seu control en rutinari. La determinaciĂł del valor sensorial i nutricional dels aliments (dues de les qualitats mĂŠs rellevants pels consumidors) presenta però una sèrie de limitacions, en especial quan el nombre de mostres a avaluar ĂŠs elevat. Això fa necessari buscar mètodes alternatius que permetin quantificar la qualitat de manera mĂŠs rĂ pida i eficient. Per exemple, lâespectroscòpia dâinfraroig proper (NIR, Near Infrared) presenta avantatges en comparaciĂł amb els mètodes analĂtics convencionals: multi-analit, rapidesa, baix cost, sense reactius, etc. Amb la finalitat que el Calçot de Valls es pugui identificar tant per les seves caracterĂstiques sensorials com nutricionals, aquesta tesi, estructurada en quatre articles, tĂŠ lâobjectiu de desenvolupar coneixement i eines per a la millora i control dâaquestes dues qualitats en els calçots. Les caracterĂstiques nutricionals del calçot han resultat ser similars a les descrites en ceba, malgrat la part que sâaprofita de la planta sigui diferent. Com passa amb altres vegetals, la cocciĂł tĂŠ un fort impacte sobre la composiciĂł del calçot, incrementant el contingut de molts dels compostos estudiats, però disminuint dâaltres com els fenols totals o, de manera drĂ stica, els flavonoides amb una pèrdua dâun 85%. La variabilitat fenotĂpica atribuĂŻble a lâambient ha estat superior a la genètica dins del tipus varietal ceba Blanca Tardana de Lleida (lâĂşnica autoritzada per la IGP). Això suggereix prioritzar la millora del maneig a la millora genètica intra-varietal si es vol incrementar la qualitat. No obstant, si considerem tres altres varietats de ceba, la variabilitat genètica sâamplia molt i, per tant, tambĂŠ les possibilitats de fer millora introduint nova variabilitat a travĂŠs dâencreuaments. Lâespectroscòpia NIR sâha mostrat com una alternativa viable en lâavaluaciĂł de la qualitat nutricional i sensorial del calçot, facilitant lâanĂ lisi dâun nombre elevat de mostres. Per a els carĂ cters quĂmics el nivell de predicciĂł dels models ha estat entre bona i excel¡lent (RPD (Ratio of Performance to Deviation) entre 1,99 i 8,07). Pel que fa a la predicciĂł de carĂ cters sensorials, malgrat els models desenvolupats presenten un nivell de predicciĂł inferior (RPD entre 1,41 i 1,78), aquets sĂłn capaços de discernir les mostres que mĂŠs sâallunyen de lâidiotip establert (dolçor elevada, baixa fibrositat i absència de gustos estranys) facilitant un primer cribatge en millora, o eliminaciĂł de fora-tipus en el control de qualitat.Award-winningPostprint (published version
Determination of chemical properties in âcalçotâ (Allium cepa L.) by near infrared spectroscopy and multivariate calibration
âCalçotsâ, the immature floral stems of second-year onion resprouts, are an economically important traditional crop in Catalonia (Spain). Classical approaches to evaluating the chemical properties of âcalçotsâ are time consuming and expensive; near-infrared spectroscopy (NIRS) may be faster and cheaper. We used NIRS to develop partial least square (PLS) models to predict dry matter, soluble solid content, titratable acidity, and ash content in cooked âcalçotsâ. To guarantee the robustness of the models, calibration samples were grown and analyzed in a first season (2014â15) and validation samples in a second season (2015â16). NIRS on puree spectra estimated dry matter and soluble solid content with excellent accuracy (R2predÂż=Âż0.953, 0.985 and RPDÂż=Âż4.571, 8.068, respectively). However, good estimation of titratable acidity and ash content required using ground dried puree spectra (R2predÂż=Âż0.852, 0.820 and RPDÂż=Âż2.590, 1.987, respectively). NIRS can be a helpful tool for âcalçotsâ breeding and quality control.Peer ReviewedPostprint (author's final draft
La postcollita del tomĂ quet de Penjar
EL TOMĂQUET DE PENJARDOSSIERN94 03Figura 1. Flors de tomĂ quet: a causa de la dehiscència longitudinal interna i inserciĂł estigmĂ tica, la reproducciĂł ĂŠs fonamentalment autògama. Autora: Maria JosĂŠ Diez NiclĂłs (COMAV, UPV).01 Origen i domesticaciĂł del to-mĂ quetEl tomĂ quet pertany a la famĂlia de les sola-nĂ cies, gènere Solanum L., secciĂł Lycopersi-con. Aquesta secciĂł inclou 13 espècies, una de les quals ĂŠs el tomĂ quet conreat, Solanum lycopersicum L.. Les espècies silvestres em-parentades amb el tomĂ quet sĂłn nadives de lâoest de lâAmèrica del Sud, des del nord de lâEquador fins al nord de Xile, travessant tot el PerĂş i tambĂŠ les Illes GalĂĄpagos. Es distri-bueixen per diversos hĂ bitats, que inclouen el desert de la costa del PacĂfic a nivell del mar, les valls verdes interandines i les regions muntanyoses dels Andes, fins a una alçada de mĂŠs de 3.000 metres. Aquesta peculiar diversitat dâambients ha contribuĂŻt a lâenorme variabilitat existent en els parents silvestres del tomĂ quet.El tomĂ quet, Solanum lycopersicum, es di-videix en dues varietats Ă mpliament distri-buĂŻdes, la varietat conreada S. lycopersicumvar. lycopersicum i S. lycopersicum var. cera-siforme.Postprint (published version
Millora de la qualitat sensorial i nutricional de les varietats tradicionals hortĂcoles: el cas del calçot (Allium cepa L.)
Sensory and nutritional quality are key elements for consumers, providing added value to agri-food products. However, there is a general perception that horticultural products have lost their quality, especially their taste.
Landraces have an identity associated with a specific area and historical origin, and are adapted to local conditions, both environmental (soil and climate) and crop management (generally low inputs). Nevertheless, they present a medium-low yield, resulting in a progressive replacement by improved varieties with high yields when cultivated in high-input systems. The landraces that remain in commerce are those which have found a high-quality niche market where consumersâ interests go beyond the price. The survival of landraces depends on their distinctive qualities, as in the case of calçots (the immature floral stems of second-year sprouts of onions (Allium cepa L.)). Calçots are typical of Catalonia, specifically from counties in the province of Tarragona where the European Union has designated them with the Protected Geographical Indication (PGI): Calçot de Valls. The calçot market is in constant evolution and expansion, and its cultivation extended beyond its traditional area many years ago.
The quality attributed to a product should be objective and measurable, in order to make its control a routine. The determination of food sensory and nutritional qualities (the most relevant qualities for consumers) presents some limitations, especially when a large number of samples needs to be tested. This necessitates the search for alternative methodologies to measure food quality in the fastest and most efficient way. For example, NIR (Near Infrared) spectroscopy presents some advantages in comparison with conventional analytical methods: multi-analyte, speed, low cost, no reagents, etc.
The objective of this thesis, structured around four articles, is to develop knowledge and tools to improve and control the nutritional and sensory qualities of calçots, with the aim of providing an identification based on those two characteristics in the Calçot de Valls.
Nutritional properties of calçots are similar to those previously reported in onion bulbs, despite the fact that the part of the plant consumed is different. As happens with other vegetables, the cooking process has an important impact on the calçotsâ composition, increasing most of the parameters tested, and decreasing others like total phenols or, more drastically, flavonoids, with an 85% loss.
The environmental influence was found to be higher than genetic influence when only considering accessions from the Blanca Tardana de Lleida onion landrace (the only one authorized by the PGI). This result suggests to prioritize management optimization over plant breeding programs to increase quality. However, when considering three other onion varieties, the genetic variability sharply increases, as do the expected advances in plant breeding introducing new variability via cross-breeds between varieties.
It would be feasible to use NIR spectroscopy to test the nutritional and sensory properties of calçots, while facilitating the management of a large number of samples. The accuracy of models developed to estimate chemical properties was between good and excellent (RPD (Ratio of Performance to Deviation) between 1.99 and 8.07). Although the developed models to estimate sensory attributes are less accurate (RPD between 1.41 and 1.78), NIR spectroscopy can help to detect those samples that differ substantially from the ideotype (high sweetness, low fiber perception and the absence of off-flavors), as a first screening in plant breeding programs or in the elimination of outliers in quality control.La qualitat sensorial i nutricional sĂłn aspectes importants per al consumidor actual i donen valor afegit als productes agroalimentaris. Hi ha però, una percepciĂł generalitzada que la qualitat, especialment el gust, dels productes hortofructĂcoles sâha anat deteriorant. Les varietats tradicionals tenen una identitat reconeguda associada a una localitzaciĂł especĂfica i un origen històric, amb una bona adaptaciĂł a condicions locals (tant a les edafoclimĂ tiques, com als sistemes tradicionals de cultiu, que solen ser de baixos inputs). Aquestes tenen però, un rendiment mitjĂ -baix, el que ha provocat la seva progressiva substituciĂł per varietats millorades, molt mĂŠs productives en cultius amb elevats inputs. Per això, la majoria de les varietats tradicionals que romanen en el comerç sĂłn aquelles que han trobat un nĂnxol de mercat amb demandes de caracterĂstiques especials, mes enllĂ del preu. La seva supervivència passa doncs per tenir qualitats distintives, com ĂŠs el cas dels calçots (tiges florals immadures de la ceba (Allium cepa L.)). Els calçots sĂłn un cultiu tĂpic de Catalunya, en concret de les comarques de Tarragona, on hi tenen atorgada una marca de qualitat europea: la IndicaciĂł GeogrĂ fica Protegida (IGP) Calçot de Valls. El mercat del calçot estĂ en constant evoluciĂł i expansiĂł, i fa anys que la seva producciĂł sâha estès tambĂŠ fora de la zona tradicional del cultiu. La qualitat que sâatribueix a un producte, hauria de ser objectiva i mesurable, per poder convertir el seu control en rutinari. La determinaciĂł del valor sensorial i nutricional dels aliments (dues de les qualitats mĂŠs rellevants pels consumidors) presenta però una sèrie de limitacions, en especial quan el nombre de mostres a avaluar ĂŠs elevat. Això fa necessari buscar mètodes alternatius que permetin quantificar la qualitat de manera mĂŠs rĂ pida i eficient. Per exemple, lâespectroscòpia dâinfraroig proper (NIR, Near Infrared) presenta avantatges en comparaciĂł amb els mètodes analĂtics convencionals: multi-analit, rapidesa, baix cost, sense reactius, etc. Amb la finalitat que el Calçot de Valls es pugui identificar tant per les seves caracterĂstiques sensorials com nutricionals, aquesta tesi, estructurada en quatre articles, tĂŠ lâobjectiu de desenvolupar coneixement i eines per a la millora i control dâaquestes dues qualitats en els calçots. Les caracterĂstiques nutricionals del calçot han resultat ser similars a les descrites en ceba, malgrat la part que sâaprofita de la planta sigui diferent. Com passa amb altres vegetals, la cocciĂł tĂŠ un fort impacte sobre la composiciĂł del calçot, incrementant el contingut de molts dels compostos estudiats, però disminuint dâaltres com els fenols totals o, de manera drĂ stica, els flavonoides amb una pèrdua dâun 85%. La variabilitat fenotĂpica atribuĂŻble a lâambient ha estat superior a la genètica dins del tipus varietal ceba Blanca Tardana de Lleida (lâĂşnica autoritzada per la IGP). Això suggereix prioritzar la millora del maneig a la millora genètica intra-varietal si es vol incrementar la qualitat. No obstant, si considerem tres altres varietats de ceba, la variabilitat genètica sâamplia molt i, per tant, tambĂŠ les possibilitats de fer millora introduint nova variabilitat a travĂŠs dâencreuaments. Lâespectroscòpia NIR sâha mostrat com una alternativa viable en lâavaluaciĂł de la qualitat nutricional i sensorial del calçot, facilitant lâanĂ lisi dâun nombre elevat de mostres. Per a els carĂ cters quĂmics el nivell de predicciĂł dels models ha estat entre bona i excel¡lent (RPD (Ratio of Performance to Deviation) entre 1,99 i 8,07). Pel que fa a la predicciĂł de carĂ cters sensorials, malgrat els models desenvolupats presenten un nivell de predicciĂł inferior (RPD entre 1,41 i 1,78), aquets sĂłn capaços de discernir les mostres que mĂŠs sâallunyen de lâidiotip establert (dolçor elevada, baixa fibrositat i absència de gustos estranys) facilitant un primer cribatge en millora, o eliminaciĂł de fora-tipus en el control de qualitat
Millora de la qualitat sensorial i nutricional de les varietats tradicionals hortĂcoles: el cas del calçot (Allium cepa L.)
Tesi amb diferents seccions retallades per drets de l'editorSensory and nutritional quality are key elements for consumers, providing added value to agri-food products. However, there is a general perception that horticultural products have lost their quality, especially their taste.
Landraces have an identity associated with a specific area and historical origin, and are adapted to local conditions, both environmental (soil and climate) and crop management (generally low inputs). Nevertheless, they present a medium-low yield, resulting in a progressive replacement by improved varieties with high yields when cultivated in high-input systems. The landraces that remain in commerce are those which have found a high-quality niche market where consumersâ interests go beyond the price. The survival of landraces depends on their distinctive qualities, as in the case of calçots (the immature floral stems of second-year sprouts of onions (Allium cepa L.)). Calçots are typical of Catalonia, specifically from counties in the province of Tarragona where the European Union has designated them with the Protected Geographical Indication (PGI): Calçot de Valls. The calçot market is in constant evolution and expansion, and its cultivation extended beyond its traditional area many years ago.
The quality attributed to a product should be objective and measurable, in order to make its control a routine. The determination of food sensory and nutritional qualities (the most relevant qualities for consumers) presents some limitations, especially when a large number of samples needs to be tested. This necessitates the search for alternative methodologies to measure food quality in the fastest and most efficient way. For example, NIR (Near Infrared) spectroscopy presents some advantages in comparison with conventional analytical methods: multi-analyte, speed, low cost, no reagents, etc.
The objective of this thesis, structured around four articles, is to develop knowledge and tools to improve and control the nutritional and sensory qualities of calçots, with the aim of providing an identification based on those two characteristics in the Calçot de Valls.
Nutritional properties of calçots are similar to those previously reported in onion bulbs, despite the fact that the part of the plant consumed is different. As happens with other vegetables, the cooking process has an important impact on the calçotsâ composition, increasing most of the parameters tested, and decreasing others like total phenols or, more drastically, flavonoids, with an 85% loss.
The environmental influence was found to be higher than genetic influence when only considering accessions from the Blanca Tardana de Lleida onion landrace (the only one authorized by the PGI). This result suggests to prioritize management optimization over plant breeding programs to increase quality. However, when considering three other onion varieties, the genetic variability sharply increases, as do the expected advances in plant breeding introducing new variability via cross-breeds between varieties.
It would be feasible to use NIR spectroscopy to test the nutritional and sensory properties of calçots, while facilitating the management of a large number of samples. The accuracy of models developed to estimate chemical properties was between good and excellent (RPD (Ratio of Performance to Deviation) between 1.99 and 8.07). Although the developed models to estimate sensory attributes are less accurate (RPD between 1.41 and 1.78), NIR spectroscopy can help to detect those samples that differ substantially from the ideotype (high sweetness, low fiber perception and the absence of off-flavors), as a first screening in plant breeding programs or in the elimination of outliers in quality control.La qualitat sensorial i nutricional sĂłn aspectes importants per al consumidor actual i donen valor afegit als productes agroalimentaris. Hi ha però, una percepciĂł generalitzada que la qualitat, especialment el gust, dels productes hortofructĂcoles sâha anat deteriorant. Les varietats tradicionals tenen una identitat reconeguda associada a una localitzaciĂł especĂfica i un origen històric, amb una bona adaptaciĂł a condicions locals (tant a les edafoclimĂ tiques, com als sistemes tradicionals de cultiu, que solen ser de baixos inputs). Aquestes tenen però, un rendiment mitjĂ -baix, el que ha provocat la seva progressiva substituciĂł per varietats millorades, molt mĂŠs productives en cultius amb elevats inputs. Per això, la majoria de les varietats tradicionals que romanen en el comerç sĂłn aquelles que han trobat un nĂnxol de mercat amb demandes de caracterĂstiques especials, mes enllĂ del preu. La seva supervivència passa doncs per tenir qualitats distintives, com ĂŠs el cas dels calçots (tiges florals immadures de la ceba (Allium cepa L.)). Els calçots sĂłn un cultiu tĂpic de Catalunya, en concret de les comarques de Tarragona, on hi tenen atorgada una marca de qualitat europea: la IndicaciĂł GeogrĂ fica Protegida (IGP) Calçot de Valls. El mercat del calçot estĂ en constant evoluciĂł i expansiĂł, i fa anys que la seva producciĂł sâha estès tambĂŠ fora de la zona tradicional del cultiu. La qualitat que sâatribueix a un producte, hauria de ser objectiva i mesurable, per poder convertir el seu control en rutinari. La determinaciĂł del valor sensorial i nutricional dels aliments (dues de les qualitats mĂŠs rellevants pels consumidors) presenta però una sèrie de limitacions, en especial quan el nombre de mostres a avaluar ĂŠs elevat. Això fa necessari buscar mètodes alternatius que permetin quantificar la qualitat de manera mĂŠs rĂ pida i eficient. Per exemple, lâespectroscòpia dâinfraroig proper (NIR, Near Infrared) presenta avantatges en comparaciĂł amb els mètodes analĂtics convencionals: multi-analit, rapidesa, baix cost, sense reactius, etc. Amb la finalitat que el Calçot de Valls es pugui identificar tant per les seves caracterĂstiques sensorials com nutricionals, aquesta tesi, estructurada en quatre articles, tĂŠ lâobjectiu de desenvolupar coneixement i eines per a la millora i control dâaquestes dues qualitats en els calçots. Les caracterĂstiques nutricionals del calçot han resultat ser similars a les descrites en ceba, malgrat la part que sâaprofita de la planta sigui diferent. Com passa amb altres vegetals, la cocciĂł tĂŠ un fort impacte sobre la composiciĂł del calçot, incrementant el contingut de molts dels compostos estudiats, però disminuint dâaltres com els fenols totals o, de manera drĂ stica, els flavonoides amb una pèrdua dâun 85%. La variabilitat fenotĂpica atribuĂŻble a lâambient ha estat superior a la genètica dins del tipus varietal ceba Blanca Tardana de Lleida (lâĂşnica autoritzada per la IGP). Això suggereix prioritzar la millora del maneig a la millora genètica intra-varietal si es vol incrementar la qualitat. No obstant, si considerem tres altres varietats de ceba, la variabilitat genètica sâamplia molt i, per tant, tambĂŠ les possibilitats de fer millora introduint nova variabilitat a travĂŠs dâencreuaments. Lâespectroscòpia NIR sâha mostrat com una alternativa viable en lâavaluaciĂł de la qualitat nutricional i sensorial del calçot, facilitant lâanĂ lisi dâun nombre elevat de mostres. Per a els carĂ cters quĂmics el nivell de predicciĂł dels models ha estat entre bona i excel¡lent (RPD (Ratio of Performance to Deviation) entre 1,99 i 8,07). Pel que fa a la predicciĂł de carĂ cters sensorials, malgrat els models desenvolupats presenten un nivell de predicciĂł inferior (RPD entre 1,41 i 1,78), aquets sĂłn capaços de discernir les mostres que mĂŠs sâallunyen de lâidiotip establert (dolçor elevada, baixa fibrositat i absència de gustos estranys) facilitant un primer cribatge en millora, o eliminaciĂł de fora-tipus en el control de qualitat
Improving the commercial value of the âCalçotâ (Allium cepa L.) Landrace: Influence of genetic and environmental factors in chemical composition and sensory attributes
Landraces are considered valuable for their close ties to local cultures, adaptation
to low inputs, and quality. âCalçotsâ are the immature floral stems of second-year
sprouts of onions from the âBlanca Tardana de Lleidaâ landrac
Estimating sensory properties with near-infrared spectroscopy: A tool for quality control and breeding of âCalçotsâ (Allium cepa L.)
Using trained panelists to evaluate sensory attributes is unfeasible when many samples must be evaluated, such as in quality control or breeding programs. Near-infrared spectroscopy (NIRS) is a rapid inexpensive method often used in food quality evaluation. We assessed the
feasibility of using NIRS to estimate sweetness, fiber perception, and off-flavors, the most important sensory attributes in cooked âcalçotsâ (the immature floral stems of second-year onion resprouts). The best results were achieved through models using interval partial least squares (iPLS) variable selection on spectra from pureed cooked âcalçotsâ, which yielded values of the ratio of performance to deviation (RPD) greater than 1.4 in all cases. Therefore, it would be feasible to use NIRS to estimate sensory properties in âcalçotsâ. This approach would be useful in initial screening to discard samples that differ substantially from the ideotype; thus, sensory analysis by trained panels could be reserved for finer discriminations.This research work was supported by the Secretaria dâUniversitats i Recerca del Departament
dâEmpresa i Coneixement (FIâDGR 2015), ACCIĂ (Generalitat of Catalonia, RD14â1â004), âCooperativa de Vallsâ,
âCooperativa de Cambrilsâ and PGI âCalçot de VallPostprint (published version
La postcollita del tomĂ quet de Penjar
EL TOMĂQUET DE PENJARDOSSIERN94 03Figura 1. Flors de tomĂ quet: a causa de la dehiscència longitudinal interna i inserciĂł estigmĂ tica, la reproducciĂł ĂŠs fonamentalment autògama. Autora: Maria JosĂŠ Diez NiclĂłs (COMAV, UPV).01 Origen i domesticaciĂł del to-mĂ quetEl tomĂ quet pertany a la famĂlia de les sola-nĂ cies, gènere Solanum L., secciĂł Lycopersi-con. Aquesta secciĂł inclou 13 espècies, una de les quals ĂŠs el tomĂ quet conreat, Solanum lycopersicum L.. Les espècies silvestres em-parentades amb el tomĂ quet sĂłn nadives de lâoest de lâAmèrica del Sud, des del nord de lâEquador fins al nord de Xile, travessant tot el PerĂş i tambĂŠ les Illes GalĂĄpagos. Es distri-bueixen per diversos hĂ bitats, que inclouen el desert de la costa del PacĂfic a nivell del mar, les valls verdes interandines i les regions muntanyoses dels Andes, fins a una alçada de mĂŠs de 3.000 metres. Aquesta peculiar diversitat dâambients ha contribuĂŻt a lâenorme variabilitat existent en els parents silvestres del tomĂ quet.El tomĂ quet, Solanum lycopersicum, es di-videix en dues varietats Ă mpliament distri-buĂŻdes, la varietat conreada S. lycopersicumvar. lycopersicum i S. lycopersicum var. cera-siforme
Nutritional values of raw and cooked 'calçots' (Allium cepa L. resprouts), an expanding crop
âCalçotâ is the Catalan name for the immature floral stems of second-year onion resprouts of the Blanca Tardana de Lleida (BTL) landrace. Highly appreciated for their sensory attributes, these resprouts are typically consumed after roasting on an open fire. Now new preparations are appearing, helping to expand the market for âcalçotsâ. This study aimed (i) to compare the nutritional and sensory characteristics of BTL âcalçotsâ versus other onion varieties; (ii) to analyze the effects of cooking and / or in vitro gastrointestinal digestion on the nutritional properties of âcalçotsâ; and (iii) to determine the influence of the environment on the antioxidant properties of âcalçotsâ.Peer ReviewedPostprint (published version