Impact of Processing on Potato Phytochemicals

Potatoes (Solanum tuberosum) are an important staple crop in both developed and developing countries around the world. These tubers offer an important source of nutrients, micronutrients, and health-promoting phytochemicals to the diet. However, reported content and process stability of phytochemicals in commercial potatoes and potato products is inconsistent. The objectives of this research were to compare phytochemical content in white/yellow and pigmented commercially relevant varieties, determine changes in phytochemical content of select potato varieties through commercial processing, and assess differences in phytochemical content between freshly “home” prepared and reconstituted, commercially processed white and sweet potato products. To carry out the first objective, phenolic acids, anthocyanins, and carotenoids were analyzed in whole and flesh of nine commercial potato varieties. Total chlorogenic acids (CQAs), the primary phenolic acid in potatoes, ranged from 43-953 mg/100 g dw and were found in greater concentrations in the whole of all varieties compared to flesh, suggesting concentration in the peel. Higher levels of CQAs were also observed in in pigmented potatoes compared to white/yellow-fleshed potatoes (318-953 and 43-88 mg/100 g dried whole potato, respectively). 5-O-Caffeoylquinic acid (5-CQA) was the primary chlorogenic acid isomer detected in all varieties of potato, followed by 4-O- and 3-O-caffeoylquinic acid (4-CQA and 3-CQA). Acylated anthocyanins in red potatoes were primarily cyanidin and pelargonidin derivatives, while those in purple varieties were primarily derivatives of petunidin with smaller amounts malvidin and delphinidin

The effect of biodynamic preparations on growth and fruit quality of giant pumpkin (Cucurbita maxima D.)

Gefördert durch den Publikationsfonds der Universität Kasse

Developing novel functional food formulations from natural sources of bioactives: quinoa, amaranth and potatoes

[ES] Existe un interés creciente, por parte de la industria alimentaria y los consumidores, por nuevos productos alimenticios cuyas funciones van más allá del rol nutricional y sensorial, teniendo también potenciales beneficios sobre las funciones fisiológicas. Los efectos de estos alimentos funcionales van desde la mejora del bienestar general hasta la reducción del riesgo de algunas enfermedades. En este sentido, una de las principales áreas de investigación en Ciencia y Tecnología de Alimentos está siendo la extracción y caracterización de nuevos ingredientes naturales con actividad biológica que se pueden incorporar a un alimento funcional, contribuyendo al bienestar del consumidor. Estos ingredientes naturales deben extraerse al mismo tiempo de forma sostenible de fuentes naturales, ofrecer características tecnológicas interesantes y proporcionar efectos biológicos positivos. El objetivo de este trabajo es la valorización de alimentos (quinoa, amaranto y patatas pigmentadas) y biorresiduos (piel de patata) como fuentes naturales alternativas de compuestos bioactivos, con potencial para ser empleados en alimentos funcionales por la industria alimentaria. La quinoa (Chenopodium quinoa Willd.) y el amaranto (Amaranthus cruentus L.) son plantas autóctonas de América Latina a las que los aztecas y incas atribuían propiedades medicinales. De hecho, estos pseudocereales han recibido mucha atención en los últimos años debido a su valor nutricional excepcional y sus posibles beneficios para la salud. Chenopodium quinoa Willd. cv. BRS Piabiru y Amaranthus cruentus L. cv. BRS Alegria son dos nuevos genotipos de estas especies adaptados al clima tropical y desarrollados por la Corporación Brasileña de Investigación Agrícola (EMBRAPA). En este trabajo se desarrolla por primera vez un estudio en profundidad sobre la composición nutricional, fisicoquímica y propiedades bioactivas in vitro de estas variedades. Los resultados obtenidos apoyan el potencial de la quinoa BRS Piabiru y el amaranto BRS Alegria como cultivos alimentarios nutritivos y como fuentes de compuestos funcionales. Además de estos pseudocereales, se estudiaron las características nutricionales y fisicoquímicas de cincuenta genotipos de patatas de veinticuatro países, con cuatro colores de pulpa diferentes (amarillo, morado, rojo y mármol), correspondientes a cuatro tipos agronómicos distintos (accesiones andinas, variedades locales, líneas reproductoras y variedades cultivadas). Se espera que los resultados obtenidos permitan la selección de nuevos genotipos de patatas para su empleo en sistemas agrícolas sostenibles, contribuyendo a la protección de la biodiversidad de la patata y, particularmente, de las accesiones andinas, las variedades locales y los genotipos coloreados (patatas rojas o moradas), de cultivo limitado hasta el momento. El interés de la industria alimentaria, los nutricionistas y los consumidores por las patatas pigmentadas como posible alimento funcional ha atraído recientemente la atención de los cultivadores. Las patatas moradas y rojas contienen altas cantidades de antocianos, variables en función del cultivar. En el presente estudio, se exploraron las patatas coloreadas como fuentes para la extracción de este tipo de compuestos, con vistas al desarrollo de colorantes alimentarios naturales. Para ello, se estudiaron extractos acuosos de distintas variedades de patata (tres de pulpa roja, tres de pulpa púrpura y un genotipo de pulpa mármol) en cuanto a su contenido de antocianos, actividades biológicas in vitro, propiedades colorantes y potencial de aplicación en la industria alimentaria. Todos los extractos presentaron actividad antioxidante, antibacteriana y antifúngica in vitro, mientras que no se detectaron efectos tóxicos. Dos extractos seleccionados se ensayaron como colorantes en una formulación de bebida refrescante, encontrando que presentaban perfiles sensoriales adecuados, así como una alta estabilidad del color durante una vida útil de 30 días, características que eran similares o mejores a las obtenidas con el colorante comercial E163, por lo que podrían usarse como colorantes alimentarios naturales. La industria de transformación de la patata se encuentra entre las más importantes a nivel mundial en cantidades procesadas, produciendo una gran cantidad de desperdicios, especialmente pieles, que oscila entre el 15% y el 40% del peso original de los tubérculos frescos. Con el objetivo de agregar valor a este importante biorresiduo, en este trabajo se estudiaron las bioactividades de la piel de diez variedades de patatas rojas y moradas, originarias de cinco países diferentes. Todas las variedades presentaron capacidad antioxidante y actividad antitumoral en las cuatro líneas celulares tumorales ensayadas. Uno de los extractos también presentó actividad antiinflamatoria y ninguno de los extractos presentó efecto tóxico sobre una línea celular hepática hasta la concentración de 304 μg/mL. Estos resultados respaldan el potencial de las pieles de patatas pigmentadas como fuentes de compuestos bioactivos para el enriquecimiento de formulaciones alimentarias funcionales. En general, los resultados de este trabajo aportan evidencias sobre el valor nutricional y funcional de cultivos alimentarios que podrían ser contemplados como fuentes alternativas y sostenibles a los cultivos de producción intensiva. Asimismo, apoyan la extracción de compuestos bioactivos vegetales y su aplicación como ingredientes funcionales o aditivos alimentarios naturales como una opción eficiente para la reutilización de residuos del procesado de alimentos, contribuyendo a la creación de cadenas de producción más sostenibles social y económicamente

Kartuli sordiresistentsuse ja kartulilehemädanikutekitaja populatsiooni uuringud Eesti sordiaretuses

A Thesis for applying for the degree of Doctor of Philosophy in AgriculturePotato (Solanum spp.) is the third most important food crop in the world after rice and wheat by FAO in 2014 in terms of human consumption. In the cold temperate climate zone, potato is one of the essential vitamins source throughout the year. People’s preferences and consumption habits have changed; thereby fluctuating demands of the food industry are setting up additional requirements for new potato cultivars. Potato late blight caused by pathogen Phytophthora infestans is one of the most destructive disease of potato. Changed environmental factors with globalization of intensive agriculture have caused disease to become more aggressive. When the ratio of Phytophthora infestans A1:A2 mating types is 50:50, the disease is able to reproduce sexually and therefore could cause soil-borne infection of late blight. In investigated fields the both mating types A1 and A2 were determined and the ratio refers to possibility of sexual reproduction. This research summarizes the development of the new medium maturity potato cultivar ‘Teele’. The cultivar has high yield and excellent culinary quality. ‘Teele’ is a B type table potato cultivar. All the properties of the cultivar ‘Teele’ were stable over the tested years. ‘Teele’ is highly resistant to the potato cyst nematode (G. rostochiensis) and moderately resistant to late blight, common scab and black scurf. The most sustainable strategy to protect yield in potato production is cultivation of late blight resistant cultivars. This study clearly showed that local potato cultivars have higher field resistance to late blight than the most widely cultivated European potato cultivars grown in Estonia.Kartul (Solanum spp.) on FAO 2014 andmetel riisi ja nisu järel tähtsuselt kolmas toidukultuur maailmas, olles parasvöötmes üheks oluliseks vitamiinirikkaks toiduallikaks. Lehemädanik (Phytophthora infestans) on kartuli kõige suuremaid saagikadusid põhjustav haigus. Inimeste ja tööstuse eelistused kartuli omaduste suhtes on muutunud ning käesoleval ajal eelistatakse tänkjama sisuga, keetmisel mittelagunevate mugulatega sorte. Keskkonnatingimuste muutumine ja intensiivne põllumajandus on kaasa toonud kartulihaiguse agressiivseks muutumise. Seetõttu on kartuli sordiaretajad olnud sunnitud otsima selliseid genotüüpe, mis oleksid nendes tingimustes stabiilsemad. Töös uuriti fenotüübilise mitmekesisuse ajalist muutumist P. infestans’i Eesti populatsioonis, ühe kartuliaretise sordiks saamist ja võrreldi erinevate sortide lehemädaniku põldresistentsust. P. infestans’i paarumistüüpide A1:A2 suhe 50:50 on kõige sobivam patogeeni suguliseks paljunemiseks ja mullas säilivate pikaealiste oospooride tekkeks. Põldudelt korjatud patogeeni isolaatide analüüs näitas, et P. infestans’i mõlemad paarumistüübid (A1 ja A2) esinesid kõikidel uuritud põldudel ning nende esinemise suhe on sobiv suguliseks paljunemiseks, järelikult ei piisa kolmeaastasest viljavaheldusest kartuli kasvatuses. Uue sordi saamiseks kasutati ETKI aretusskeemi, mis kestis 12 aastat. Uus kartulisort ’Teele’ on keskvalmiv, kõrge saagi ja kvaliteediga ning suurepäraste kulinaarsete omadustega B tüüpi lauakartul. ‘Teele’ on mõõdukalt resistentne lehemädaniku, hariliku ja musta kärna ja resistentne kollase kartuli-kiduussi (G. rostochiensis) suhtes. Veel näitab see töö selgelt kohalike kartulisortide suuremat lehemädaniku põldresistentsust võrreldes teiste Eestis enamkasvatatavate Euroopa sortide põldresistentsusega.Publication of this thesis is supported by the Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences

Protein and sugar content of tubers in potato plants treated with biostimulants

The use of biostimulants and cultivar selection play an important role in modern potato farming because they influence tuber yield and quality. The nutritional value and processing suitability of potato tubers are affected by their content of total protein, reducing sugars and sucrose. The aim of this study was to determine the effect of biostimulants on the content of total protein, glucose, fructose and sucrose in potato tubers (skin, flesh and whole tubers with skin), at harvest and after 5 months of storage. The experimental materials included tubers of five edible potato cultivars: Irga, Satina, Valfi, Blaue St. Galler and HB Red. During the growing season, potato plants were treated with the following biostimulants: Asahi SL, Bio-Algeen S-90, Kelpak SL and Trifender WP. Control plants were not treated with biostimulants. The total protein content of tubers was determined by the Kjeldahl method. Simple sugars and sucrose were determined by high-performance liquid chromatography. At harvest, total protein concentration was significantly higher in purple- and red-fleshed cultivars than in cream- and yellow-fleshed cultivars. An analysis of tuber parts revealed that flesh had the highest protein content. The total protein content of tubers increased during storage. Biostimulants had no significant effect on total protein concentration in tubers at harvest or after storage. The content of simple sugars and sucrose was higher in the skin, flesh and whole tubers of purple- and red-fleshed cultivars, than in cream- and yellow-fleshed cultivars. Potato tubers with colored flesh accumulated the highest amounts of total sugars. Biostimulants, in particular Bio-Algeen S-90 and Kelpak SL, contributed to the accumulation of monosaccharides and the disaccharide in potato tubers, and, in consequence, total sugars. Their concentrations in potato tubers increased during storage

Annual Report: 2008

I submit herewith the annual report from the Agricultural and Forestry Experiment Station, School of Natural Resources and Agricultural Sciences, University of Alaska Fairbanks, for the period ending December 31, 2008. This is done in accordance with an act of Congress, approved March 2, 1887, entitled, “An act to establish agricultural experiment stations, in connection with the agricultural college established in the several states under the provisions of an act approved July 2, 1862, and under the acts supplementary thereto,” and also of the act of the Alaska Territorial Legislature, approved March 12, 1935, accepting the provisions of the act of Congress. The research reports are organized according to our strategic plan, which focuses on high-latitude soils, high-latitude agriculture, natural resources use and allocation, ecosystems management, and geographic information. These areas cross department and unit lines, linking them and unifying the research. We have also included in our financial statement information on the special grants we receive. These special grants allow us to provide research and outreach that is targeted toward economic development in Alaska. Research conducted by our graduate and undergraduate students plays an important role in these grants and the impact they make on Alaska.Financial statement -- Grants -- Students -- Research reports: Partners, Facilities, and Programs; Geographic Information; High-Latitude Agriculture; High-Latitude Soils, Management of Ecosystems; Natural Resources Use and Allocation; Index to Reports -- Publications -- Facult

A panoramic review on phytochemistry, pharmacological potential, health benefits, and versatility of Solanum tuberosum L.

The potato (Solanum tuberosum L.) belongs to the family Solanaceae and is one of most versatile crops, vital components of the human diet in numerous countries. It is regarded as one of the most promising crops for reducing world hunger and poverty. It is one of the foremost non-grain crops in the world, being a cost-effective and easily accessible food with several health benefits. The entire plant including peel, tuber, and leaves are used in traditional medicine. Potatoes are high in carbohydrates, lipids, phenolic acids, anthocyanins, carotenoids, proteins, flavonoids, vitamins, potassium, phosphorus, copper, and fiber. The purpose of this review study was to present up-to-date information on novel metabolites discovered in potatoes that play a role in preventing illness and improve human well-being. We attempted to assemble data on the variety of pharmacological activity including antioxidant, anti-diabetic, antihypertensive, anticancer, antiobesity and anti-inflammatory properties of potatoes, as well as their function in enhancing gut health and satiety. In-vitro investigations, human cell culture, experimental animal studies have revealed that potatoes have a variety of health-promoting qualities. The observations and recommendations presented here are scientifically interesting for food chemistry, pharmacology, nanotechnology, and toxicology. These may also contribute to enhance nutrition, food safety, and human health

Roots and Tuber Crops as Functional Foods: A Review on Phytochemical Constituents and Their Potential Health Benefits

Starchy roots and tuber crops play a pivotal role in the human diet. There are number of roots and tubers which make an extensive biodiversity even within the same geographical location. Thus, they add variety to the diet in addition to offering numerous desirable nutritional and health benefits such as antioxidative, hypoglycemic, hypocholesterolemic, antimicrobial, and immunomodulatory activities. A number of bioactive constituents such as phenolic compounds, saponins, bioactive proteins, glycoalkaloids, and phytic acids are responsible for the observed effects. Many starchy tuber crops, except the common potatoes, sweet potatoes, and cassava, are not yet fully explored for their nutritional and health benefits. In Asian countries, some edible tubers are also used as traditional medicinal. A variety of foods can be prepared using tubers and they may also be used in industrial applications. Processing may affect the bioactivities of constituent compounds. Tubers have an immense potential as functional foods and nutraceutical ingredients to be explored in disease risk reduction and wellness

Effect of cultivar, growth environment and developmental stage on phenolic compounds and ascorbic acid in potato tubers grown in Finland

Potato is the most important non-cereal crop worldwide. It has been consumed in the South American Andes for thousands of years and then introduced to Europe in the XVII century. Thanks to its nutritional value and high yield it was then expanded to the rest of the world. Since potato is a staple food crop for many countries, it plays a crucial role in maintaining food security and reducing malnutrition. Unfortunately, the sustainable production of this crop is threatened by climate change that causes rising global temperatures and altering weather conditions all over the world. The main purpose of this study was to understand how weather variables affected by latitude and year impact the biosynthesis of phenolic compounds and ascorbic acid in pigmented potato cultivars. The first aim of this work was to develop reliable extraction methods for anthocyanins and ascorbic acid, as previous studies showed contradictory information on the anthocyanin content when using fresh, freeze-dried or steamed potatoes. The second aim was to assess the effect of temperature, cultivar, and tuber developmental stage on the expression of genes involved in the biosynthesis of phenolic compounds and the content of anthocyanins, phenolic acids, and ascorbic acid in potato cultivars with purple or yellow flesh and/or skin. The third aim was to evaluate the effect of weather conditions (affected by latitude and year), cultivar, and tuber developmental stage also on the gene expression levels and on the content of anthocyanins, phenolic acids, and ascorbic acid in potato cultivars grown at two different latitudes and two consecutive years in Finland. The results showed that anthocyanins were most effectively extracted from freeze-dried potatoes using 70 % acidified methanol. Tris(2-carboxyethyl) phosphine hydrochloride was the most effective in reducing dehydroascorbic acid to ascorbic acid and was therefore the most suitable reducing agent for the determination of total ascorbic acid. Cultivar was the main variable that affected the gene expression levels of the enzymes involved in the biosynthesis of phenolic compounds as well as the anthocyanin and phenolic acid profile. The main anthocyanin in the purplefleshed and purple-skin cultivars was a petunidin derivative or malvidin derivate (depending on the cultivars), while the main anthocyanin in the red-skinned cultivar was a pelargonidin derivative. The effect of tuber developmental stage was evaluated in the second and third aim of this study. In both cases, it was found that the content of the main anthocyanins and phenolic acids as well as ascorbic acid tended to decrease with tuber maturation, although the content of minor anthocyanins and phenolic acids did not show a clear tendency to increase or decrease. The gene expression levels also remained relatively stable for most of the genes studied except for F3ʹH which showed a clear decreasing trend during tuber development in the purplefleshed cultivars. When potato tubers were cultivated under controlled temperatures (at 13 and 18 °C), it was found that the studied temperatures did not affect the content of anthocyanins, but mildly affected the content of phenolic acids and ascorbic acid during tuber development. However, when tubers reached full maturity no significant differences in the content of anthocyanins, phenolic acids or ascorbic acid were observed between the tubers grown at the two studied temperatures. Our third aim was to evaluate the impact of latitude on the content of phenolic compounds and ascorbic acid in potato tubers, and for that we evaluated two latitudes and replicated the experiment in two consecutive years for repeatability purposes. However, when we processed our data, we realized that the synthesis of the metabolites of interest were mainly affected by the interaction of “Latitude: Year” and less by the solo effect of “Latitude” or “Year”. So, when potato tubers were cultivated at different latitudes (61.2 and 64.8° N) and years (2014 and 2015) in Finland, potato plants cultivated at 61.2° N in 2014 (Kokemäki) were exposed to temperatures above 18 °C and reduced precipitation events. The pigmented potato tubers produced in this trial had the lowest expression levels of most of the genes involved in the phenylpropanoid pathway and the lowest content of phenolic compounds and ascorbic acid. On the other hand, when potato plants were cultivated at the same latitude (61.2° N) but in 2015 (Köyliö), the plants were exposed to temperatures between 13 and 18 °C and good precipitation events. These plants produced tubers with the highest gene expression levels, as well as the highest contents of anthocyanins and phenolic acids. The potato plants cultivated at 64.8° N in 2014 and 2015 (Muhos) produced tubers with intermediate contents of anthocyanins, phenolic acids, and ascorbic acid. Positive gene-gene, gene-anthocyanins and anthocyaninanthocyanin correlations were also stronger and more significant at 61.2° N in 2015 (Köyliö) than in the other field trials. In this study, we observed that a mild increment in temperature combined with poor precipitation events at 61.2° N in 2015 (Kokemäki) had a detrimental effect on the synthesis of bioactive compounds in potato tubers. However, during the last five years, temperatures in Finland have exceeded those of 2015 and Finnish potato growers have reported difficulties due to unexpected weather events. Further research is needed to better understand the potentially synergistic interactions of the main weather variables affecting the synthesis of bioactive compounds in potato tubers.----- Viljojen jälkeen peruna on maailman tärkein viljakasvi. Sitä on syöty ensin Etelä-Amerikan Andeilla tuhansien vuosien ajan, josta se tuotiin Eurooppaan XVII vuosisadalla. Ravintoarvonsa ja suuren satonsa ansiosta se levisi sitten muualle maailmaan. Koska peruna on monien maiden perusviljelykasvi, sillä on ratkaiseva merkitys elintarviketurvan ylläpitämisessä ja aliravitsemuksen vähentämisessä. Valitettavasti tämän viljelykasvin kestävää tuotantoa uhkaa ilmastonmuutos, joka nostaa maapallon lämpötiloja ja muuttaa sääolosuhteita kaikkialla maailmassa. Tämän tutkimuksen päätarkoituksena oli ymmärtää, miten leveyspiirin ja vuodenajan säämuuttujat vaikuttavat fenolisten yhdisteiden ja askorbiinihapon synteesiin pigmentoituneissa perunalajikkeissa. Työn ensimmäisenä tavoitteena oli luotettavan uuttomenetelmän kehittäminen antosyaaneille ja askorbiinihapolle. Aiemmissa tutkimuksissa oli antosyaanipitoisuuksista saatu ristiriitaisia tietoja, tutkittaessa tuoreita, kylmäkuivattuja tai höyrytettyjä perunoita. Toisena tavoitteena oli arvioida lämpötilan, lajikkeen ja mukulan kehitysvaiheen vaikutusta fenolisten yhdisteiden biosynteesiin osallistuvien geenien ilmentymiseen sekä antosyaanien, fenolihappojen ja askorbiinihapon pitoisuuksiin perunalajikkeissa, joiden malto ja/tai kuori on violetti tai keltainen. Kolmantena tavoitteena oli arvioida sääolosuhteiden (joihin vaikuttavat leveysaste ja vuosi), lajikkeen ja mukulan kehitysvaiheen vaikutusta antosyaanien, fenolihappojen ja askorbiinihapon pitoisuuksiin sekä näiden yhdisteiden biosynteesiin osallistuvien geenien ilmentymistasoihin perunalajikkeissa, joita kasvatettiin kahdella eri leveysasteella ja kahtena peräkkäisenä vuonna Suomessa. Tulokset osoittivat, että antosyaaneja saatiin eniten uuttamalla kylmäkuivattuja perunoita happamoidulla 70 % metanolilla. Tris(2-karboksietyyli) fosfiinihydrokloridi oli tehokkain pelkistämään dehydroaskorbiinihappo askorbiinihapoksi ja siten soveltui parhaiten askorbiinihapon kokonaismäärän määrittämiseen. Perunalajike oli tärkein muuttuja, joka vaikutti geeniekspressioprofiiliin sekä antosyaani- ja fenolihappoprofiiliin. Pääantosyaani violettimaltoisissa ja - kuorisissa lajikkeissa oli petunidiinijohdannainen tai malvidiinijohdannainen (lajikkeesta riippuen), kun taas punakuorisen lajikkeen pääantosyaani oli pelargonidiinijohdannainen. Mukulan kehitysvaiheen vaikutusta arvioitiin tämän tutkimuksen toisessa ja kolmannessa tavoitteessa, ja molemmissa tapauksissa havaittiin, että tärkeimpien antosyaanien ja fenolihappojen sekä askorbiinihapon pitoisuudet vähenivät yleensä kypsymisen myötä. Fenolihappojen pitoisuuksissa ei havaittu systemaattisia eroja kasvukauden aikana. Myös geenien ilmentymistasot pysyivät suhteellisen vakaina useimpien tutkittujen geenien osalta lukuun ottamatta F3ʹH:ta, jonka ilmeneminen selvästi väheni violettimaltoisissa lajikkeissa mukulan kypsyessä. Kolmantena tavoitteena oli arvioida leveysasteen vaikutusta perunan mukuloiden fenolisten yhdisteiden ja askorbiinihapon pitoisuuksiin. Perunoita kasvatettiin kahtena eri vuonna kahdella eri leveysasteella. Tulokset osoittivat, että tutkittavien parametrien "leveysaste" ja "vuosi" erillisvaikutukset aineenvaihduntatuotteiden synteesiin olivat vähemmän merkittäviä kuin ko. parametrien yhdysvaikutus "leveysaste: vuosi". Kun perunamukuloita viljeltiin eri leveysasteilla (61,2 ja 64,8° N) ja eri vuosina (2014 ja 2015), havaittiin, että perunakasvit, jotka kasvoivat kokeessa leveysasteella 61,2° N vuonna 2014 (Kokemäki), altistuivat yli 18 °C:n lämpötiloille ja vähäisemmille sateille. Tällöin kehittyi perunamukuloita, joissa fenyylipropanoidireittiin osallistuvien geenien ilmentymistasot olivat alentuneet ja antosyaanien, fenolihappojen ja askorbiinihapon pitoisuudet olivat vähentyneet. Toisaalta perunakasvit, jotka kasvoivat kokeessa leveysasteella 61,2° N vuonna 2015 (Köyliö), altistuivat runsaille sateille ja 13-18 °C:n lämpötiloille, ja ne tuottivat mukuloita, joiden geenien ilmentymistasot sekä antosyaanien ja fenolihappojen pitoisuudet olivat korkeimmat. Vuosina 2014 ja 2015 Muhoksella (64,8° N) kasvatetut perunat tuottivat mukuloita, joiden antosyaani-, fenolihappo- ja askorbiinihappopitoisuudet olivat keskitasoa. Positiiviset geeni-geeni-, geeni-antosyaani- ja antosyaani-antosyaani-korrelaatiot olivat myös vahvempia ja merkitsevämpiä kuin muissa kenttäkokeissa. Tässä tutkimuksessa havaitsimme, että vuonna 2015 lämpötilan lievä nousu yhdistettynä vähäisiin sademääriin leveysasteella 61,2° N (Kokemäki) vaikutti haitallisesti perunan mukuloiden bioaktiivisten yhdisteiden synteesiin. Viimeisten viiden vuoden aikana Suomen lämpötilat ovat kuitenkin ylittäneet vuoden 2015 lämpötilat, ja suomalaisten perunanviljelijöiden on raportoitu kohdanneen vaikeuksia odottamattomien sääilmiöiden vuoksi. Lisätutkimusta tarvitaan, jotta voidaan ymmärtää paremmin perunan mukuloiden bioaktiivisten yhdisteiden synteesiin vaikuttavien tärkeimpien säämuuttujien mahdollisesti synergistiset yhteisvaikutukset