--- topic: "Local Food" title: "Freshness and Nutrient Loss After Harvest" order: 2 description: "Vitamin C fades after harvest, by very different amounts depending on the crop, while minerals and fiber hold. What storage studies show about time, temperature, ripeness and local versus shipped produce." question: "Does produce lose nutrients between harvest and your plate?" answer: "Produce likely loses some vitamin C within days of harvest, depending on the crop, but minerals and fiber hold and cold storage slows the loss." actions: - "Eat tender leafy greens within a few days: in a lab test, salad leaves kept at fridge temperature lost 35–86% of their ascorbate (vitamin C) over 10 days [1]." - "Keep produce cold, and quickly: in a shelf-life study of packaged salad, vitamin C loss was more sensitive to temperature than bacterial spoilage was [2]." - "Favor in-season produce and vine-ripened tomatoes: fall supermarket broccoli had nearly twice spring's vitamin C, and vine-ripened cherry tomatoes were firmer and higher in sugars [3][4]." cautions: - "Local is not a nutrient guarantee: in one comparison of seven crops, local fruit had more vitamin C than imported fruit, but local vegetables had less [5]." confidence: 3 confidenceNote: "Several lab studies show vitamin C falling in storage, by very different amounts; one found most antioxidants stable, and none tested a health effect." evidenceSummary: rctCount: 0 observationalCount: 0 metaAnalysisCount: 0 replicated: true newestStudyYear: 2026 references: - id: "1" pmid: "28530571" title: "Novel insights into ascorbate retention and degradation during the washing and post-harvest storage of spinach and other salad leaves" authors: "Dewhirst RA, Clarkson GJJ, Rothwell SD, et al." year: 2017 journal: "Food Chem" - id: "2" pmid: "27745710" title: "Shelf-life prediction models for ready-to-eat fresh cut salads: Testing in real cold chain" authors: "Tsironi T, Dermesonlouoglou E, Giannoglou M, et al." year: 2017 journal: "Int J Food Microbiol" - id: "3" pmid: "17852499" title: "Nutritional quality of organic, conventional, and seasonally grown broccoli using vitamin C as a marker" authors: "Wunderlich SM, Feldman C, Kane S, et al." year: 2008 journal: "Int J Food Sci Nutr" - id: "4" pmid: "25916229" title: "From producer to consumer: greenhouse tomato quality as affected by variety, maturity stage at harvest, transport conditions, and supermarket storage" authors: "Verheul MJ, Slimestad R, Tjøstheim IH" year: 2015 journal: "J Agric Food Chem" - id: "5" pmid: "22222913" title: "An improved and fast UHPLC-PDA methodology for determination of L-ascorbic and dehydroascorbic acids in fruits and vegetables. Evaluation of degradation rate during storage" authors: "Spínola V, Mendes B, Câmara JS, et al." year: 2012 journal: "Anal Bioanal Chem" - id: "6" pmid: "42324783" title: "How does the nutritional quality of fresh fruit and vegetables change during storage?" authors: "Carlin F, Amiot-Carlin MJ, Aubert C, et al." year: 2026 journal: "Crit Rev Food Sci Nutr" - id: "7" pmid: "17880151" title: "Evolution of antioxidant capacity during storage of selected fruits and vegetables" authors: "Kevers C, Falkowski M, Tabart J, et al." year: 2007 journal: "J Agric Food Chem" - id: "8" pmid: "28737734" title: "Storage of Fruits and Vegetables in Refrigerator Increases their Phenolic Acids but Decreases the Total Phenolics, Anthocyanins and Vitamin C with Subsequent Loss of their Antioxidant Capacity" authors: "Galani JHY, Patel JS, Patel NJ, et al." year: 2017 journal: "Antioxidants (Basel)" - id: "9" pmid: "20131793" title: "Relationship between fresh-packaged spinach leaves exposed to continuous light or dark and bioactive contents: effects of cultivar, leaf size, and storage duration" authors: "Lester GE, Makus DJ, Hodges DM" year: 2010 journal: "J Agric Food Chem" - id: "10" pmid: "18237131" title: "How does tomato quality (sugar, acid, and nutritional quality) vary with ripening stage, temperature, and irradiance?" authors: "Gautier H, Diakou-Verdin V, Bénard C, et al." year: 2008 journal: "J Agric Food Chem" - id: "11" pmid: "30372995" title: "Stability of total folates/vitamin B(9) in irradiated watercress and buckler sorrel during refrigerated storage" authors: "Pinela J, Morales P, Cabo Verde S, et al." year: 2019 journal: "Food Chem" - id: "12" pmid: "33015121" title: "Pre- and Post-harvest Factors Affecting Glucosinolate Content in Broccoli" authors: "Ilahy R, Tlili I, Pék Z, et al." year: 2020 journal: "Front Nutr" --- Some, mostly vitamin C. After harvest, produce is still alive and slowly uses up its most fragile compounds [6]. In lab tests, salad leaves kept at fridge temperature lost 35 to 86 percent of their ascorbate (vitamin C) in 10 days [1], while minerals and fiber changed far less [6]. Warmth speeds the loss [2]. We found no study that tests distance by itself; time since picking, temperature and the crop are what the studies measure. ## How the science works After harvest, fruit and vegetables keep changing physiologically. Refrigeration slows this, shelf life runs from days for fragile crops to months for sturdy ones, and different compounds change differently [6]. **What fades and what holds.** Vitamin C is the most fragile nutrient. A 2026 review found that it changes a lot in storage while minerals and fiber change far less, that species and variety shape a food's composition more than storage does, and that stored produce still has enough nutrients to deliver the benefits of eating it [6]. Many plant antioxidants hold up too: in a test of purchased fruits and vegetables, most spoiled visibly before their antioxidant capacity fell, with banana and broccoli the exceptions [7]. **How fast, in what.** Detached salad leaves kept in the dark at 4 °C lost 35–86% of their ascorbate in 10 days, 59% on average; baby iceberg lettuce lost the most, while wild rocket and mizuna showed no significant fall. Mature spinach leaves lost about 80% in 3 days, baby spinach 25–45% [1]. A test of 19 fruits and vegetables from Indian markets, held for 15 days at 4 °C, found vitamin C generally fell, but three assays disagreed about which items lost most, and some rose [8]. **Warmth and light.** In a model of packaged salad, shelf life ended at about a 20% loss of vitamin C, and that loss was more sensitive to temperature than bacterial growth [2]. Light can help: spinach in clear boxes at 4 °C kept more of most vitamins under continuous light than in the dark, though lit leaves wilted more [9]. **Ripe or picked green.** Red cherry [tomatoes](/tomatoes/lycopene-cooking-and-cancer-protection) picked at the breaker stage (first color) and ripened off the plant were softer and lower in soluble solids than vine-ripened ones [4], and ripening on the plant builds sugars, carotenes and ascorbate [10]. **Local versus shipped.** Few studies isolate distance. One comparison found more vitamin C in local than imported fruit but the reverse in vegetables [5], and in supermarket broccoli fall values were almost double spring values, a bigger swing than organic versus conventional [3]. **What it means.** The levers are time, temperature and the crop. Fresh-picked and well chilled is usually best, but a few days in the fridge costs some vitamin C, not the benefits of vegetables, and local produce is not automatically more nutritious than shipped produce [5]. ## The evidence in detail ### Salad leaves and vitamin C Dewhirst and colleagues (2017) stored eleven types of salad leaf in the dark at 4 °C in unsealed packaging and measured ascorbate by titration. Every type lost ascorbate over 10 days, though the fall in wild rocket and mizuna was not statistically significant. The mean loss was 59% and the largest 86%, in baby iceberg lettuce. In spinach, mature leaves lost about 80% in 3 days against 25–45% for baby leaves, and after 10 days baby leaves held about 30% of their starting ascorbate and mature leaves 10%. Washing spinach, especially with mechanical agitation, increased the loss, and radiolabeled ascorbate ended up mainly as oxalate, a sign of oxidative breakdown [1]. The limits: detached leaves, one temperature, no light, and a titration that counts only the reduced form of vitamin C, not dehydroascorbic acid [8]. Galani and colleagues (2017) held 19 fruits and vegetables from Indian markets at 4 °C for 15 days. Total phenolics fell by up to 29.7%, phenolic acids rose and antioxidant activity fell sharply. For vitamin C, three assays disagreed: the largest falls were 71.8% in tomato (titration), 32.0% in spinach (spectrophotometry) and 49.4% in sugar beet (a third assay), and a few items rose [8]. [Folate](/folate) behaves differently by crop: it fell in watercress over 7 days at 4 °C but was unchanged in buckler sorrel after 12 [11]. In a test by US Department of Agriculture scientists, spinach stored in clear retail boxes at 4 °C for up to 9 days had higher vitamin C, folate, vitamin K1, vitamin E and lutein under continuous light than in the dark, where levels fell or held; beta-carotene and violaxanthin were the exceptions [9]. ### A conflicting result Kevers and colleagues (2007) tracked antioxidant capacity in purchased fruits and vegetables during storage. In most it did not fall, and in some it rose in the days after purchase along with phenolic compounds; produce spoiled visibly before any significant loss, except banana and broccoli, and ascorbic acid and flavonoids were generally stable [7]. The studies used different crops, ages and conditions, so they do not settle how much any one item loses. Broccoli [glucosinolates](/broccoli/glucosinolates-cancer-prevention-and-gut-health) show the same spread: a review of storage experiments found totals unchanged after several days at 4 to 8 °C in some studies, some individual glucosinolates rising, and total content down by up to 80% after a week at 1 °C plus three days at 15 °C in another [12]. ### Temperature and the cold chain Tsironi and colleagues (2017) modeled a packaged mixed salad (two lettuces and rocket) at 2.5 to 15 °C and then tested the model in a real cold chain. Shelf life ended when Pseudomonas bacteria reached 8 log cfu/g or vitamin C fell 20%. The activation energy was 122.6 kJ/mol for vitamin C loss and 69.1 for bacterial growth, so vitamin C is the more temperature-sensitive; by our arithmetic from that figure it is lost about three times as fast at 10 °C as at 4 °C. In the real chain the effective temperature ranged from 3.7 to 8.3 °C, and 2 to 3 days of home storage left 1 to 8 days of shelf life at 4 °C [2]. ### Ripeness at picking Verheul and colleagues (2015) harvested two red tomato types at three maturity stages from commercial greenhouses and simulated storage, transport and supermarket conditions. Vine-ripened red cherry tomatoes were 30% firmer and had 55% more soluble solids and 11% more titratable acids than tomatoes picked at breaker and ripened to red. Transport conditions over four days (temperature, light, UVC or ethylene) changed quality traits, with differences that persisted through three weeks of supermarket storage, and ethylene raised lycopene 3.7-fold in cherry tomatoes [4]. Across ripening, reducing sugars, carotenes and ascorbate rose in tomatoes, and fruit light and temperature changed final levels [10]. ### Local versus shipped, and season Spínola and colleagues (2012) compared seven crops from two origins: local fruit had more vitamin C than imported fruit, vegetables the opposite, and ascorbic and dehydroascorbic acid moved in opposite directions in storage, so total vitamin C was not always affected [5]. Wunderlich and colleagues (2008) assayed supermarket broccoli bought in different seasons, when it could be local or shipped far. Fall vitamin C was almost twice spring (P = 0.021 organic, 0.012 conventional), more than the gap between organic and conventional. Season and distance are tangled together in that design [3]. ### Where the evidence is thin These are laboratory measurements on a handful of crops, with assays that disagree, and we found no study testing whether the losses change health. A 2026 review concludes that overall levels stay high enough to deliver the benefits of regular fruit and vegetable eating [6]. Moderate confidence (3 of 5). See also [fresh vs frozen produce](/fresh-vs-frozen-produce) and [vitamin C](/vitamin-c).