Posts Tagged: Postharvest Technology Center
I’ll admit that one of my favorite things to do on a hot day is to walk into an air-conditioned room. That burst of cool air in those first moments can be so refreshing.
It turns out I’m not alone — fruits and vegetables like to be cool on hot days too.
Controlling temperature helps regulate the aging process of a fruit, along with its water loss and microorganism growth. Storing fruits and vegetables at their lowest safe temperatures means they taste better and last longer.
To help us know the best ways to store fresh produce at home, the UC Davis Postharvest Technology Center offers a free PDF poster Storing Fresh Fruits and Vegetables for Better Taste, which includes tips for different fruits and vegetables, from avocado to watermelon.
Knowing the right temperature is only part of the battle for farmers, who are responsible for the first links in the cold chain. Getting produce out of the sun and cool for storage can be a big challenge — and an expensive one.
But a farmer in New York, Ron Khosla, answered this challenge with a tool that can help make cooling produce less expensive for small-scale farmers. He created the CoolBot, a micro-controller that turns a well-insulated room with a regular air conditioner into a commercial cool room for storing fruits and vegetables.
Just as small-scale American farmers struggle with affordable cooling, so do smallholder farmers elsewhere in the world. Researchers with the Horticulture Collaborative Research Support Program (Horticulture CRSP) decided to test the CoolBot device, first at the UC Davis Student Farm and then with farmers in India, Honduras and Uganda.
Indeed, the CoolBot-equipped rooms worked, and the program is building more in Bangladesh right now. But there is a catch: Farmers must have access to reliable grid electricity for a cool room like this to work. To address this problem, the CoolBot in Uganda was powered with solar photovoltaic cells, but that led to another set of challenges — expensive equipment and fear of theft.
So how do you effectively cool vegetables, hot from a field, without grid electricity? A solution that is low-cost, effective and off-grid has not been found yet. In an effort to uncover such a solution, Horticulture CRSP will soon be launching a technology design competition that asks that very question. Can you answer this challenge?
I first tasted a feijoa (fay-zho-uh, or pineapple guava) as a student here at UC Davis many years ago. A friend showed me her secret trees (south side of Wellman in Davis — tons on the ground right now!), and I was hooked. I didn’t think much of it at the time, other than thinking this is one of the best things I have ever eaten in my life. It tastes better than candy, and ripens right around Halloween - sweet! I had never seen or heard of a feijoa. You likely haven’t either, so I’m writing to introduce you.
First a little history. This subtropical plant originated in the higher altitude regions of central South America, but has since been introduced and grown commercially in Europe, California, New Zealand, South Africa and the area around southern Russia. In California, Sutter and Yuba counties were the hot spot for growing pineapple guavas in the late 1980s. Farmers in that area, who benefitted from the kiwi expansion a few years before, enthusiastically jumped into the feijoa business, however did not realize the same success.
According to Adel Kader, UC Cooperative Extension specialist emeritus, "the nurseries that provided the trees were not accurate in identifying the different variety of trees, and there was a large difference in the taste.”
So a farmer had no idea if he had a good tree or not. Additionally, judging fruit maturity is difficult since the fruits do not significantly change color as they ripen and drop to the ground when they’re mature. So the optimal picking strategy is by “touch picking” where if you touch a fruit and, if it comes off the plant, it’s ready to eat. Imagine doing that for a whole orchard.
Back to the present. I rediscovered feijoas after riding my bike down our street before the green waste pick-up a couple years ago and noticed about 30 feijoas in my neighbor’s pick-up pile! They didn’t know you could eat them. So, yes, I picked them out of the pile and introduced my neighbors to the deliciousness of the pineapple guava. And then I promptly went out and bought myself a tree to plant in my own yard.
Feijoas taste like taking the best elements of strawberry, guava and pineapple and mixing them together. They smell pleasantly sweet and flowery. To eat a feijoa, cut (or rip) it in half and scoop out the inside creamy white flesh (a little brownish color is fine to eat). Feijoas are a good source of vitamin C, fiber and potassium, and they even contain a little protein.
So, where can you find feijoas? Well, if you're in Davis, visit the south side of Wellman. Or, you can plant your own tree like I did (you can reference the Postharvest Technology Center’s Produce Fact Sheet for Feijoas here), or you can go to your local farmers market. It’s a short season, so this is the weekend to search them out. When you find them, Kader suggests you “look for a larger fruit with a slight give and a nice aroma.” You won’t be disappointed.
A year ago, a co-worker wrote a post on this blog entitled “It’s just a waste.” The sad facts of food waste are something we pay attention to since we work for the UC Postharvest Technology Center. A key component of our Center’s mission is to “reduce postharvest losses.” This topic also hits close to home on a personal level since I have always struggled with using up produce before it spoils. I go shopping about once a week, and tend to purchase just a bit more produce than what we will actually eat – in the hopes that one of us will suddenly adopt healthier eating habits by increasing our intake of fresh produce. I place the produce in my fruit ripening bowl, on the counter, or in the fridge, according to the recommendations on my handy produce storage chart. But nearly every week something goes awry, usually with my schedule, and I end up not serving the delicious produce-based meals I had planned, or I forget to pack my lunch, and oops, the negative effects of delayed consumption hit my produce.
I want to do better, too! I hereby resolve to try harder to stick with my menu plan, pay closer attention to produce on the counter and the fridge (sometimes known affectionately in the produce industry as the “black hole”), and I will try very hard to be more creative in my use or preservation of quickly ripening produce.
My single biggest challenge is bananas. I try to buy a smaller hand of 5 to 6 bananas with some green tint left. They go on my banana hook in a cooler corner of my kitchen. At least half the weeks of the year those bananas have black spots within 3 to 4 days, and by day 5 there are usually 2 to 3 bananas left that are no longer appealing to my family. So almost half the bananas I buy usually don’t get eaten. I know, I know, “buy a smaller hand of bananas,” you say. That’s easier said than done, at least at the markets in which I shop.
Thankfully there are many cooks out there willing to share their recipes for creative ways to use up an over-supply of bananas. Below is a starting list of ideas that I’ll be drawing from as I make an effort to reduce produce waste, and especially banana waste, in our home.
- Slice into 1-inch chunks, freeze in a single layer on a wax paper covered cookie sheet. Transfer into a zip-bag and return to the freezer to use as needed for fruit smoothies or other cooking projects
- Banana bread or banana muffins
- Homemade banana ice cream
- Banana layer cake with cream cheese frosting
- Slice lengthwise, sauté in butter and ¼ tsp. rum flavoring until golden brown, and serve on ice cream
- Banana crunch cookies
- Make banana pancakes, add chocolate chips if desired (here’s a link to a pancake recipe called “Chunky Monkey” my son-in-law likes to make)
- Peel, insert a lollipop or popsicle stick and freeze. Eat as is, or dip in melted chocolate.
- Banana drop cookies
- Slice, dip in fresh lemon juice, and dry in a dehydrator
- Make a warm spiced banana topping that’s great on ice cream or gingerbread
- Banana oatmeal bar cookies
- Banana pudding
- Fruit Skewers
- Bananas Foster
- Banana Daiquiri
- Tropical banana bar cookies with raisins, pecans and coconut
- Banana cream pie
- Peanut butter, banana and rum bar cookies
- Burrito Bananas Foster
- Fruit Salad
- Banana crepes
- Dessert Pizza
- Banana Bundt cake with caramel frosting
- Fruit salsa, served with cinnamon tortilla chips
- Banana split
- Strawberry-banana parfait with yogurt and granola
Aiming to energize the seed industry cluster surrounding UC Davis, Seed Central, an initiative of the Seed Biotechnology Center at UC Davis and SeedQuest, recently highlighted postharvest handling and food safety at their monthly forum. Recordings of invited guest speakers, Marita Cantwell, Trevor Suslow and Roberta Cook, UC Cooperative Extension specialists with expertise in post harvest science, show the passion they feel for their respective subjects and why we're fortunate to have them on our team. Cantwell and Suslow are in the UC Davis Department of Plant Sciences; Cook is in the UC Davis Department of Agricultural and Resource Economics.
Cantwell, a postharvest physiologist, specializes in handling and storage of intact and fresh-cut vegetables. In her talk, she describes the Postharvest Technology Center itself and gives an overview of the handling challenges of many vegetable varieties.
A plant pathologist, Suslow’s program centers on studying the effects of microflora on the postharvest quality of perishable produce. With much attention to current food safety a priority, Suslow’s produce safety overview and specific case examples help us all (ahem) digest this hot topic.
Cook, an agricultural economist, focuses on fresh produce marketing and food distribution. This presentation centers on North American vegetable markets. Even if you’re not a grower, shipper or retailer, Cook's description of trends in the produce industry are fascinating — we all eat fruits and vegetables every day. She talks about things we might not ever think about.
UC Davis is addressing food security and economic development in Africa, Southeast Asia, Central America, and elsewhere, by coordinating an international horticulture program. The Horticulture Collaborative Research Support Program (Hort CRSP; pronounced "hort crisp") is one of 10 CRSP programs that focus on global food production and solving food and nutrition problems in developing countries. UC Davis leads the Hort CRSP, with funding support from the U.S. Agency for International Development (USAID).
Examples of projects conducted by researchers and educators throughout the world include:
- Inexpensive cold storage systems in rural, developing areas to prolong food longevity; see page 2
- Concentrated solar drying of fruits and vegetables in East Africa; see page 3
- Improving safety and quality of tomatoes in Nigeria; see page 3
- Smallholder flower production in Honduras for export markets; see page 3
The overarching goals of the Hort CRSP are to reduce poverty and improve nutrition and health of the rural poor, while improving the profitability and sustainability of horticulture in the developing world. Priorities in the Hort CRSP include gender equity, sustainable crop production, postharvest technology, food safety, market access, and financing. The program awards research funding in the U.S. and abroad to:
- Realize opportunities for horticultural development
- Improve food security
- Improve nutrition and human health
- Provide opportunities for income diversification
- Advance economic and social conditions of the rural poor, particularly women
In the three years since the program’s inception, several projects have been completed, and many are ongoing. The program’s website offers a plethora of information, along with newsletters that highlight individual projects.
The program also has a YouTube channel, with videos on Hort CRSP projects. Some of the videos are about projects that are especially important in developing countries, including:
- The TRELLIS project — bringing together graduate students and in-country development organizations; YouTube link
- Using cell phones to give real-time information to growers in rural areas of India; YouTube link
- Inexpensive cultivation practices for smallholder farmers; YouTube link
- Indigenous products increase incomes in Ghana; YouTube link
- Saving indigenous crop seeds in Southeast Asia for resource-poor farmers; YouTube link