Abstract:
Low temperature storage as an alternative to anti-sprouting chemicals in potato storage may induce reducing sugars (RS) accumulation (i.e. glucose and fructose) in potato tubers. This phenomenon is called \"cold induced sweetening\" (CIS) and occurs in certain varieties. CIS leads to a decrease in the organoleptic qualities and darkening of processed potato and the accumulation of toxic molecules such as acrylamide. To identify potato varieties suitable for storage at low temperatures, we screened six commercial processing varieties: Lady Claire (LC), Verdi, Kiebitz (KB), Pirol, Agria and Markies for their CIS characteristics and sprout-forming potential after storage at 4 °C and 8 °C. Our findings reveal that 4 °C storage allows for efficient sprout reduction in all six tested varieties for up to 4.5 months of storage. Three CIS-resistant varieties, namely Verdi, Lady Claire and Kiebitz, were identified as able to be stored for up to four months at 4 °C with limited increase in glucose content. Conversely, Pirol, Agria and Markies showed an increase in glucose content with a decrease in storage temperature and can be considered as CIS-susceptible varieties. After processing into crisps, the CIS-susceptible varieties displayed poor crisp color quality (brown to black color crisps) after storage for two months at 4 °C compared to the storage at 8 °C, whereas the CIS-resistant varieties had good crisp color quality (pale yellow color crisps) after storage at both 4 and 8 °C. Interestingly, the trends of total RS and/or glucose content in the CIS-resistant and in the CIS-susceptible varieties were correlated with the trends in Vacuolar Invertase (VInv) gene expression for most varieties, as well as with the trends in acrylamide content after processing. In addition, reconditioning of Markies variety after storage at 4 °C by gradually increasing the temperature to 15 °C resulted in a significant decrease of VInv transcript levels (reduction of 80 %), acrylamide content (reduction of 75 %) and glucose content when compared to a storage at 4 °C without reconditioning. Those results demonstrate that the reconditioning technique is a key factor for a sustainable potato storage and for improving the quality of processed potatoes.
摘要:
低温储存作为马铃薯储存中的抗发芽化学品的替代可以诱导马铃薯块茎中的还原糖(RS)积累(即葡萄糖和果糖)。这种现象被称为“冷诱导甜味”(CIS),并发生在某些品种中。CIS导致加工马铃薯的感官品质下降和变黑,并导致有毒分子如丙烯酰胺的积累。确定适宜低温贮藏的马铃薯品种,我们筛选了六个商业加工品种:克莱尔夫人(LC),威尔第,Kiebitz(KB),Pirol,Agria和Markies在4°C和8°C下储存后的CIS特征和发芽潜力。我们的发现表明,4°C的储存可以有效地减少所有六个测试品种的发芽,储存时间长达4.5个月。ThreeCI抗S品种,即威尔第,克莱尔夫人和Kiebitz,被鉴定为能够在4°C下储存长达四个月,而葡萄糖含量的增加有限。相反,Pirol,Agria和Markies显示葡萄糖含量随储存温度的降低而增加,可以认为是CIS敏感品种。加工成薯片后,与在8°C下储存两个月相比,在4°C下储存两个月后,对CIS敏感的品种显示出较差的酥脆颜色质量(棕色到黑色的薯片),而CIS抗性品种在4和8°C储存后具有良好的脆色品质(浅黄色薯片)。有趣的是,CIS抗性和CIS易感品种的总RS和/或葡萄糖含量的趋势与大多数品种的液泡转化酶(VInv)基因表达趋势相关,以及加工后丙烯酰胺含量的变化趋势。此外,在4°C下储存后,通过逐渐增加温度至15°C来重新调节Markies品种,导致VInv转录水平显着降低(减少80%),当与在4°C下储存而不进行预处理相比时,丙烯酰胺含量(减少75%)和葡萄糖含量。这些结果表明,修复技术是马铃薯可持续储存和提高加工马铃薯质量的关键因素。