What Fruits Have Pulp

What Fruits have pulp. include peaches, oranges, avocados, dates and kiwis. Fruits are derived from a wide range of plants on planet Earth. One definition of fruit is “the ripened ovary of a flowering plant”. A common characteristic of all fruits is that they contain seeds. Others tend to mature into fruits as the plant grows.

WHAT IS FRUIT PULP AND HOW IS IT USED?

Fruit pulp is the most basic product created by the processing of fresh fruit. It contains both the juice and the pulp, which is the stringy fibre which is often removed from fruit juice. 

Fruit pulps can be processed and stored for long periods of time without losing their colour, flavour or texture. They are used in a huge range of applications including gelato, fruit flavoured yoghurt, jelly, fruit drinks, jams, lollies and even specialty beer brewing.

Before you use fruit pulp, it’s important to understand the differences between each type of product and how it is processed so that you can confidently plan your production and operations, and get the results you need from each ingredient.

The different processing formats have a big role in:

1. The grade of fruit selected;
2. How the finished pulp is handled; and
3. What flavours, colours and aromas you can expect.

Outlined below are the different type of fruit pulp products available, the key differences to be aware of, and how each is best used.

FRESH FROZEN

How it is prepared:

• Only the best quality fruit is used.
• Fruit is typically hand-sorted.  
• No torn, rotten or over-ripe fruit is processed as it may ruin the batch.  
• Sound fruit is pulped, it may be pH stabilised using acid additions (citric, ascorbic).
• Sugar levels (brix) may be adjusted to correct for natural fluctuations in sweetness.This is done to match the natural brix level of the fruit and maintain a consistent product (competing products will have a nice flavour but will list water and sugar as primary ingredients).Typically the batch sizes are smaller because it’s inherently a riskier process because it uses a more expensive product.

Impact on price: Fresh frozen is the most expensive option due to the labour-intensive sorting and inspection required, and also because any fruit that doesn’t meet specification is discarded, meaning yields are lower.

Aroma, flavour and colour: The pulp should taste like you blended the fruit fresh yourself, without freezing. You should also get the full range of flavour, aroma and colour.

Handling: Must be stored frozen. Defrost in a 4C fridge and use within a few days of defrosting.

Application: Fresh frozen pulp is best used when that single ingredient is the key defining flavour of the end product, e.g. mango gelato, strawberry sauce etc.  It is also best used when the product has a nutritional focus, as the nutrients in the fruit are best preserved when the product is unheated, i.e. raw cold pressed juice.

PASTEURIZED

How it is prepared:

• Fruit is not hand-sorted. 
• Bulk bins of fruit are processed without individual inspection, with some unsuitable product discarded.  
• Fruit is pulped and heated to 95C for 10-30 seconds to destroy organisms that may spoil the product (e.g. yeast, mould, enzymes).

Impact on price: Cheaper than fresh frozen due to improved yields (less fruit rejected) and a more mechanised process with less manual intervention.

Aroma, flavour and colour: Flatter flavour and aroma. It resembles fresh but misses some of the upper flavour notes, with a darker colour due to heating.

Handling: Product must be stored frozen. You can get up to a week after defrosting to use the product due to lower starting micro levels.

Application: Can be used for sorbets/gelato but the flavour is not as prominent. Beer brewers may prefer this product if the beer has to travel long distances in variable temperature environments.  Because it is heated to destroy organisms that may spoil, you may also prefer this product if your customers are high risk, or the impact of failures is high e.g. airline foods.

ASEPTIC

How it is prepared:

• No sorting of fruit for over/under ripe or torn skin.
• Bulk bins processed with little fruit discarded.  
• Fruit is rapidly heated to around 135C for 1-2 seconds then cooled, packed into sterilised packaging.

Impact on price: A highly mechanised processes means production costs are low.  As very little fruit is unsuitable the yields are high resulting in overall low unit costs.

Aroma, flavour and colour: Aroma is indistinct, flavour is flatter and colour is darker due to caramelisation of sugars.

Handling: Safe at ambient temperatures for months to years due to low oxygen in UHT packs and zero starting micro count.

Application: Best used where cost is critical, where this ingredient doesn’t play a critical role in the overall flavour profile of the end product, or where the flavour of this ingredient is not prominent.  Examples might be using aseptic banana in a “mango, pineapple and banana” fruit drink.

Pulp

The soft, juicy, edible flesh that is contained within the outer skin or peel that covers a fruit or vegetable. Pulp may a term that is also used to describe a purée made from cooked or uncooked fruit and vegetables. It is the substance that remains after all the juices have been removed. The Pulp of fruit is a common ingredient that is added to food and beverages as they are manufactured.

Fruit Pulp Processing

Fruit pulp is a mass of pressed fresh fruit not meant for immediate consumption. Production of fruit pulp avoids wasting food, preserves the flavors and nutrient value of the fruit product. Processed fruit pulp is an ingredient in beverages, sauces, baby foods, jellies, smoothies and bakery products. Tradition and manufacturing procedures dictate the distinction between fruit juice, puree, and pulp. Still, naming and labeling are complex depending on regulations, type of fruit, texture and consistency, preservation methods, as well as sugar or solid content (measured in Degrees Brix). Depending on your desired output, there are various fruit pulper machines for various stages of production that make the process quicker and more efficient.

Tropical Fruit Pulps: Processing, Product Standardization and Main Control Parameters for Quality Assurance

ABSTRACT

Fruit pulp is the most basic food product obtained from fresh fruit processing. Fruit pulps can be cold stored for long periods of time, but they also can be used to fabricate juices, ice creams, sweets, jellies and yogurts. The exploitation of tropical fruits has leveraged the entire Brazilian fruit pulp sector due mainly to the high acceptance of their organoleptic properties and remarkable nutritional facts. However, several works published in the last decades have pointed out unfavorable conditions regarding the consumption of tropical fruit pulps. This negative scenario has been associated with unsatisfactory physico-chemical and microbiological parameters of fruits pulps as outcomes of little knowledge and improper management within the fruit pulp industry. There are protocols for delineating specific identity and quality standards (IQSs) and standardized good manufacturing practices (GMP) for fruit pulps, which also embrace standard operating procedures (SOPs) and hazard analysis and critical control points (HACCP), although this latter is not considered mandatory by the Brazilian legislation. Unfortunately, the lack of skilled labor, along with failures in complying established protocols have impaired quality of fruit pulps. It has been necessary to collect all information available with the aim to identify the most important hazards within fruit pulp processing lines. Standardizing methods and practices within the Brazilian fruit pulp industry would assurance high quality status to tropical fruit pulps and the commercial growth of this vegetal product towards international markets.

Key words:
processing; standards of identity and quality; vegetable product; food safety

INTRODUCTION

Quality is increasingly referred to as an important element within the food industry. The growing demand for high quality food products has disseminated the use of quality management tools to meet expectations of consumers and market throughout the world, and also to manufacture safe products, thereby reducing costs and production losses 

Consumer expectations are much more demanding than in the past. Nowadays, there are major concerns related to food safety (pathogenic microorganisms and harmful substances) and food quality that involve various aspects, from the entire production chain up to fair labor payments and environmental impacts to soil and water. The rapidly increasing demand for fresh fruits has reflected changes in consumer preferences for healthier foods, which should also be produced through environmentally friendly processes 

Brazil is an essentially agricultural country with a huge potential for cultivating traditional and exotic fruits. Fruit pulp is the most basic product obtained from fresh fruit processing, although its production and conservation have not been correctly accomplished in Brazil. In the last decades, numerous studies have pointed out the technological inadequacy of Brazilian fruit pulps for human consumption, which reflect lack of qualified labor, standardized processing methods and good manufacturing practices (GMPs) in small and medium-sized companies. These aspects are considered important because they guarantee the adequate quality control on raw materials and processed foods.

This review article gathers the major shortcomings of quality control within the Brazilian fruit pulp production sector. Moreover, the most important aspects for obtaining innocuous and nutritious fruit pulps to meet consumer expectations are also outlined.

FRUIT MARKET AND FRUIT PULP PRODUCTION

Brazil produces a wide diversity of tropical, subtropical and temperate fruits due to its continental dimensions and variety of climates. Brazil also presents regional productions specialized in certain types of fruits 

Brazil is the third world’s largest fruit producer with an annual production of 42,416 million tons in 2012, after China and India. Unprocessed fresh fruits accounts for 53% of the total commercial Brazilian fruit production, of which 3% is used to supply the international market. Of the total amount of fresh fruits 47% is processed by the national food industry. This means that 71% of total Brazilian fruit production is consumed by the domestic market, while the remaining 29% is exported to abroad 

European Union and United States are the main purchasers of Brazilian fruits and their derivative products. According to the Brazilian Fruit Institute (IBRAF), 759,400 and 2,149,800 tons of fresh and processed fruits, respectively, were exported in 2010, with focus on tropical fruits, whose sensorial acceptance and production have been continuously increasing in the past two decades.

Pulp and juice processing are important agro-industrial activities for the food production sector as they add economic value to fruits, avoid fruit wasting and minimize losses during commercialization of unprocessed fresh fruits. Pulp and juice processing also constitute an alternative way by which fruit growers sell their products.

One advantage of industrializing fruit pulp is the consumption of fruits native to particular regions throughout the country, some of which being highly coveted on the international market  Fruit pulps could also supply the food industry for producing juices, ice creams, candies and confectionery and dairy products such as yogurts . The markets of concentrated juice and pulp are notably relevant because they seek to attract consumers fundamentally by the idea of fruit nutritional value preservation 

Preserving highly perishable fruits constitute a big challenge for agro-industries. These industries have been focused mainly on processing methods that conserve the physical structure and the nutritional and sensory attributes of fruits. Agro-industries have also been focused on expanding the consumer market of fruit pulps. Nevertheless, the lack of standard procedures within the fruit processing sector, from the farm to the final consumer, is among the major shortcomings to be overcome by fruit pulp agro-industries .

FRUIT PULP PROCESSING AND ASPECTS FOR QUALITY MAINTENANCE

Postharvest loss is an important shortcoming for fruit pulp production because certain fruits remain alive after they are harvested. This implies that specific procedures and recover methods must be adopted in order to extend fruit shelf-life and use surplus production. These measures are taken according to the fruit type, which helps defining the best ways to handle fresh fruits during harvest, transportation, storage and commercialization.

Climacteric fruits, such as peach, apple, mango, guava, passion fruit, among many others, can be harvested when they reach the physiological maturation point, i.e., when they reach an ideal size and format, even if they are not ready for consumption. In this sense, climacteric fruits are suitable for industrialization because they provide higher uniformity in the maturation process. On the other hand, non-climacteric fruits, such as orange, lemon, pineapple and grape, do not have the ability to reach attributes that are typical of ripe fruits (sweetness, color, and acidity) after harvesting. In this case, non-climacteric fruits must be harvested only when they are completely ripened.

Consumption of fruit pulp and juice is rising continuously due to the consumer preference for healthy eating habits. Advances on food technology have enabled successful fruit processing and pulp freezing storage in appropriate packages within the food industry. Commercialization of frozen fruit pulps also make possible consumption of fruits little known, which have already attracted interest from the international market, especially those from Cerrado, North and Northeast regions of Brazil 

Fruit pulp production line normally embraces the following steps: reception, weighing, pre-selection, washing and sanitization, pulping, packaging and freezing. In general, fruits are frozen when there is insufficient amount of fruit to be pulp, whereas unripe fruits are cooled after the washing/sanitization step. The flowchart in Figure 1 illustrates the overall process that should be adopted in order to manufacture good quality fruit pulps. Pre-selection/selection of fruits, washing and sanitization, cooling or freezing are the most important steps and must be efficiently performed 

Figure 1
Fruit pulp processing flowchart.

For small and micro-sized agro-industries, harvesting fruits at the maturation point is the most recommended practice. The maturation point is commonly referred to as firm ripe or “turning”, which means that fruits will rapidly attain the maturation degree suitable for processing. A number of parameters defined by law, including physiological maturation (if the fruit is climacteric or non-climacteric), pH, soluble solid content (°Brix) and acidity, should be determined still in field in order to harvest fruits with characteristics apposite for processing ¹. After harvesting, fruits must be suitably transported and handled to avoid mechanical injuries, heating and accumulation of metabolites.

The reception step consists in receiving, weighing and pre-selecting fruits, thus avoiding entrance of unsuitable fruits within the processing line and improving the final product quality. Fruit pre-selection should be conducted efficiently in order to remove physically damaged, dirty or completely decayed fruits which could spoil the final product.

Storing insufficient amounts of ripe fruits for processing should be preferably done after the sanitization step. Cleaned fruits can be organized into plastic boxes and stored under refrigeration or in ventilated and little humid areas for preventing rodent attacks and proliferation of molds and insects.

Cleaning and sanitization are different steps although they are fundamental for removing microbial load from fruits. Cleaning usually consists in washing fruits with water to eliminate impurities and part of the microbial load brought from plantations, whereas sanitization is generally carried out with chlorine-based substances.

Sodium hypochlorite is one of the most popular chlorine-based sanitizers whose antimicrobial activity is rather widespread . When sodium hypochlorite is dissolved in cold water, it reacts to form hypochlorous acid, which is a strong oxidizing agent that is effective against foodborne pathogens (S. aureus, L. monocytogenes and E. coli). Hypochlorous acid serves to disinfect surfaces, fruits and vegetables, by killing suspended and film-forming microorganisms ^16-19.

Fruit immersion into sodium hypochlorite solution is usually performed for 15 min, using concentrations between 20 and 100 ppm to reduce the microbial load to permissible levels. Long-term usages of sodium hypochlorite solution should be previously tested due to the time-dependent chlorine degradation. Fruits must be subsequently rinsed in order to remove hypochlorite residue

Table 1
Initial sodium hypochlorite concentration and residual chlorine concentration after sanitization (15 min) of some tropical fruits.

Sodium hypochlorite is advantageous over various sanitizers due to its low cost, easy storage when produced in situ, disinfection efficiency similar to that of chlorine gas, and can remain at residual concentration. On the other hand, sodium hypochlorite is toxic and corrosive, especially at high concentrations. It also tends to decompose in contact with air, spreading chlorine gas which is toxic.

The chlorine antimicrobial activity efficiency is influenced by:

• Presence of organic matter: Organic materials such as food residue decrease the chlorine antimicrobial activity. Thus, fruits must be previously cleaned to attain a proper sanitization efficiency;
• Chlorinated solution pH: pH affects microbial activity. The highest chlorine antimicrobial activity occurs at pH 6.5 – 7.0 because hypochlorite is highly unstable at pH 4;
• Temperature: Sanitizers often exhibit synergistic effect with temperature. However, chlorinated compounds decompose into chlorine gas at elevated temperatures, in addition to increasing their corrosive potential over heating;
• Concentration: As aforementioned, chlorine levels of 20 and 200 ppm are used to sanitize fruits and processing, which must be washed afterwards to remove the chlorinated solution residue;
• Contact time: Fruit sanitization with sodium hypochlorite is efficiently attained within 30 min. Longer treatments should be avoided because the chlorine corrosive potential increases significantly over time

The water used in the fruit sanitization step must present physical, chemical and microbiological qualities in consonance with the ordinance 2914 of December 12, 2011 of the Brazilian Ministry of Health. These quality aspects include absence of dirties and fecal coliforms and Salmonella (in 100 mL), reduced number of heterotrophic bacteria, appropriate pH and turbidity. Sanitization water must also contain sodium hypochlorite at concentrations between 0.2 – 2.0 ppm, or chlorine dioxide at a minimum level of 0.2 ppm throughout all water distribution system in order to warranty the use of disinfected water in fruit sanitization 

According to the ordinance CVS 6-99 of the Health Surveillance Center of São Paulo Secretary of Health, the chemicals and their final concentrations authorized for food sanitization are listed below:

• Sodium hypochlorite at 2.0 – 2.5%, to obtain concentrations from 100 to 250 ppm;
• Sodium hypochlorite at 1%, to obtain concentrations from 100 to 250 ppm;
• Organic chlorine at 100 – 250 ppm.

Controlling the sanitization process by proper adjustment of the active chlorine concentration is important to ensure not only elimination of microbial load, but also to preserve fruit organoleptic attributes. Sanitization of surfaces, machines and tools with chlorinated solutions 100 – 200 ppm and subsequent rinsing should also be performed before and after fruit pulp processing.

Fruits must be separated according to their maturation degree. Unripe fruits must be stored under adequate temperature and relative humidity in order to control the ripening process and extend their shelf-life. This preserves the physical and sensory characteristics of fruit pulps.

According to the ordinance CVS 6-99 of the Health Surveillance Center of São Paulo Secretary of Health, perishable food storage has to meet the following temperature criteria:

• Frozen foods: -18 ºC with tolerance of up to -12 ºC;
• Cooled foods: 6 – 10 ºC, or in conformity with supplier’s specifications;
• Refrigerated: up to 6 ºC, with tolerance of 7 ºC.

Storage chamber temperature should be ideally monitored by charts displaying inferior and superior temperature limits (Figure 2). In this way, the storage chamber is operated most of the time within the permitted temperature range. Points that lie outside the limits can also be identified.

Figure 2
Chamber temperature monitoring chart.

Fruit freezing must be performed as rapidly as possible in order to maintain the fresh fruit attributes. The usual freeze temperature range is between -12 and -23 °C. From chemical and technical points of view, the ideal temperature is -18 °C and this should be held constant throughout the freezing step. The cooling times to reach -5 °C and -18 °C should not be longer than 8 and 24 h, respectively 

Fruit pulp processing is carried out with the aid of pulper-finishers containing sieves with different apertures to separate peels, seeds and fibers from pulp. Fruit pulping should be performed continuously (all raw materials must be separated for continuous processing, while the packaging sector has to be prepared to receive the pulp) and rapidly, because the cooling and freezing times directly influence on the fruit pulp quality. Hand peeling, such as that used for pineapple and soursop, is another important aspect of pulp processing because food handlers contact directly internal portions of fruits. This requires maximum personal hygiene and sanitized premises. Hand peeling also constitutes a time-consuming additional stage of the fruit pulp production with high probability of microbial spoilage and fruit oxidation (nutrient and color losses).

The homogenization stage is ideally performed by coupling the pulper-finishers to the homogenization tank and packing machine, so that exposition of fruit pulp to light, air, and processing environment is efficiently avoided. Food preservatives are generally added to fruit pulps at the homogenization stage to increase consumer acceptance or extend their shelf-life.

The normative instruction No 01, 2000, of the Brazilian Ministry of Agriculture, Livestock and Supply (MAPA) defines that fruit pulps used in beverage industrialization are permitted to contain chemical additives, such as acidulants (acidity regulators), synthetic preservatives, and natural colorants, at concentrations equivalent to those allowed for fruit juices, with some specific exceptions.

The use of food preservatives aims to prevent fruit pulps from oxidation and microbial spoilage. Citric acid and sodium benzoate are among the most used food additives; the first one is used as an acidulant in sufficient amounts, while the latter is used as a preservative at maximum concentration of 1 g per kg or L of product. These limiting concentrations are listed in the resolution RDC No. 8 March 6, 2013, which establishes food additives permitted in fruits, vegetables and mocotó jelly.

Acidulants are added to food products with the purpose of intensifying their sour attribute. Citric acid is the most used acidulant in the food industry due to:

• Versatile applications, including “flavouring” (taste and aroma) to synergy with antioxidant compounds, in addition to controlling pH.
• Easy obtaining (fermentation with Aspergillus niger).
• Relatively low cost 

Although citric acid is highly compatible with most fruits, its usage as an acidulant should not be generalized. Citric acid may affect fruit sensory attributes, for example, in the case of pineapple. Ascorbic acid is considered more suitable than citric acid for acerola, soursop and cashew. Lemon juice is recommended for pineapple and hog plum fruits. In the case of passion fruit, the use of acidulants is not recommended due to the high acidity of this fruit.

Benzoic acid and its derivatives, such as sodium benzoate, are efficient in controlling growth of yeasts and molds at pH range 2.5 – 4.0, over which they occur predominantly in a chemically dissociated form. Sodium benzoate is a microbiostatic agent that exhibits temporary activity on microorganisms. It is compatible with fruit pulps, whose shelf-life is no longer than 45 days, but for durable food products sodium benzoate must be used in conjunction with other antimicrobial agents. The maximum sodium benzoate concentration authorized in fruit juices and pulps is 1000 ppm, which is not deleterious to human health, being excreted as hippuric acid after reacting with glycine

Fruit pulp quality inspection takes into account the standard microbiological and physico-chemical parameters for fruit pulps. Microbiological parameters are defined by product class (fruit-derived consumer goods, for instance), whereas physico-chemical parameters are specifically defined by fruit type because of the peculiar characteristics of each fruit .

In Brazil, microbiological quality of commercial fruit pulps is mainly legislated by the resolution RDC No 12, 2001, of ANVISA which approves technical regulation on the microbiological standards for foods and the normative instruction No 12, 1999, of MAPA which legislates the quality parameters of fruit pulps . The MAPA’s normative instruction No 1, 2000, determines the main standardized physico-chemical parameters of fruit pulps with basis on acidity, total soluble solid content (°Brix), pH, total solids content, total natural sugar content, and vitamin C content. This normative instruction defines fruit pulp as a non-fermented, non-concentrated and undiluted product obtained from pulpy fruit crushing 

The microbial load in fruit-derived products is normally an outcome of raw material conditions and washing step efficiency, in addition to the hygienic-sanitary conditions of food handlers . Microbiological parameters are important food quality aspects because they allow evaluating food products in relation to processing conditions, storage, distribution, shelf-life and risk to public health 

Reaching high fruit pulp quality standards requires effective hygienic conditions from the production stage until commercialization. This also involves control on raw materials, industrial processing, transport and storage. Inside a processing plant, there must exist proper maintenance of equipment, water supply network, sewage network and electricity, as well as a correct stock flux. Training and ongoing supervision of food handlers by competent professionals is also indispensable because all activities are always performed by a considerable number of employees 

Fruit pulp obtaining is a basic physical extraction process with possible addition of food preservatives and acidulants. Therefore, the final pulp quality will be highly dependent on the fresh fruit characteristics. In this context, fruit integrated production (FIP or PIF in portoghese) is a program that was developed in collaboration with MAPA to evaluate adequacy of fruit-derived products. FIP is based on four pillars: Production basis organization, system sustainability, and process and information monitoring (Figure 3). The main purpose of FIP is to monitor increases in the Brazilian fruit agribusiness exportation and Brazilian fruit quality. The application of natural resources with focus on environmental conservation and agriculture sustainability is the principal operation strategy of FIP. This has been implemented through systematic evaluation of fruit production with periodic monitoring, use of integrated pest management (IPM) techniques, reduction of pollutant inputs to ensure diversity and equilibrium to agro-ecosystems, and to ensure adequate and safe working conditions to employees .

Problems on physico-chemical standards of fruit pulps

Table 3 compares some physico-chemical data of tropical fruit pulps already published in literature. The largest discrepancies between the physico-chemical parameters and the decreed values are observed for total soluble solid content (°Brix), total titratable acidity (g citric acid/100 g) and vitamin C content.

Table 3
Summary of published studies on physico-chemical analysis of tropical fruit pulps.

The main variables affecting the total soluble solid content of fruit pulps are the rainfall regime during harvest season and fruit maturation degree. These natural problems indicate wrong cultivation or harvest management. They are also associated with poor quality raw materials and pulp dilution (water addition), which is a common practice justified by some producers as a way to improve the pulping step efficiency.

Diluting fruit pulps to reduce the total solid content (°Brix) to minimum levels required by the Brazilian legislation is a fault, since the law states that “fruit pulp is an unfermented, not concentrated and undiluted product obtained from pulpy fruits by a technical process and with a minimum total solid content from the fruits edible portion”.

The discrepancies of acidity and vitamin C content among the published data are mainly ascribed to the low quality of the fruits used to produce pulps, thus indicating fruit deterioration. Fruits improper to be eaten fresh due to complete decaying, mechanical injuries and deformations or breakage during transport are often used in pulp production.

It is worth pointing out that every activity, from postharvest to fruit processing, affects the phytochemicals and antioxidant properties of fresh fruits, the latter related to bioactive compounds beneficial to human health, such as vitamins C and E, carotenoids and polyphenols. In this context, the determination of vitamin C content in fruits is very important because vitamin C degradation favors the appearance of non-enzymatic browning and bitter taste in fruit pulps ³³. Furthermore, vitamin C is an important food quality indicator due to its thermolabile nature. The presence of vitamin C in foods may lead to believe that other food nutrients are also preserved ^33,34. The processing method, storage condition, packaging, exposure to oxygen, light, and metallic catalysts, initial vitamin C content, and microbial load are among the principal factors that lead to vitamin C degradation .

Considering fruit pulp processing solely as a physical extraction method, the main aspects that must be controlled for pulp quality assurance are raw material quality, fruit washing/sanitization efficiency, processing time (prevent aeration or unnecessary lighting), and effective freezing procedures (observing the entire cold chain, processing, transport and sale to consumer). Campelo et al. observed that the vitamin C content of acerola pulp produced in laboratory under controlled conditions decreased by 40% after 12-month storage. The remaining vitamin C content was still greater than the recommended daily intake (RDI), 90 mg/day. The lost vitamin C percentage decreased when acerola pulp was pasteurized before storing. Yamashita et al. found that the vitamin C content of pasteurized acerola pulp reduced by 10 to 15% for storage times between 10 – 120 days, regardless of the freezing temperature (-12 and -18°C). On the other hand, fresh acerola fruits lost between 20 and 40% of vitamin C depending on the freezing temperature, with best vitamin C maintenance occurring at -18°C. Heat treatments involving temperatures above 60°C are able to inactivate enzymes. Therefore, vitamin C oxidation occurs throughout the exhaustion and pasteurization steps, but the remaining content becomes more stable after pasteurization due to enzyme inactivation .

How to Reuse Fruit Pulp After Juicing

If you enjoy making delicious, vitamin-packed juices, or adding a squeeze of zesty lemon or lime juice to your cooking, you’re probably used to finding yourself with a lot of leftover fruit that you’re not quite sure what to do with. 

When it comes to lemon peel, there are plenty of solutions, and you can find some useful tips in our guide to different uses for lemon peel. But there is a lot of goodness in the leftover pulp, too, including most of the fibre. Find out how to put that fruit to good use with these clever kitchen hacks, and you’ll never need to throw pulp away again.

Seven ways to reuse your leftover fruit juice pulp

Add interest to smoothies

Try adding some nutritious pulp to the blender when you make your next breakfast smoothie. This will add both flavour and texture, giving the smoothie a thick, milkshake like consistency. It will also add extra nutrients and plenty of fibre, so you’ll feel fuller for longer, and not be tempted to snack between meals.

Make flavoured ice cubes

We all know how important it is to stay hydrated, but the taste of plain water can get a little boring sometimes. Ice cubes made with fruit pulp can be a great way to add some fruity flavour to your glass of water, not to mention extra nutrients. Just add some fruit pulp to your ice cube tray along with the water and freeze for easy fruity ice cubes.

Liven up pancakes

Add some juicy fruit pulp to your pancake batter for a burst of fruity flavour and some added texture. The pulp will also provide some extra moisture, so you may want to reduce some of your other wet ingredients a little.

Make chewy fruit leathers

Turn your leftover pulp into fruit leathers, a delicious and healthy fruit candy. All you need to do is press the pulp and lay it evenly on a lined baking sheet, then put the sheet in a dehydrator, or in the oven on its lowest setting for 12 to 14 hours. Once the fruit is dried, cut it into strips and enjoy.

Make popsicles

Make your popsicles into ‘pulpsicles’ by sprinkling some leftover fruit pulp into your popsicle moulds before you pour in the juice. A bit of extra pulp adds flavour, texture and nutrients to your favourite iced treat.

Add to homemade granola

Give your homemade granola and energy bars an extra dose of vitamins and minerals and a delicious fruity flavour with some added pulp. Try using a cup of pulp for every three cups of oats for a healthier, fruitier granola.

Add to baked goods

Make healthier versions of your favourite baked goods by adding juicy fruit pulp. The extra liquid from the fruit means you can cut some of the fat from the recipe and it will still stay moist.

Most used fruits for juicing

Now you know what to do with your leftover pulp, you can get juicing without worrying about waste. If you’re looking for some inspiration for your next juice mix, here are some of the most popular fruits used in juicing.

Apples

With their crisp, sweet flavour, apples are a firm favourite with juicers. They are a great source of fibre, potassium and antioxidants, but they are also high in sugars, so avoid drinking too much.

Oranges

Oranges are well known as an excellent source of vitamin C, which helps maintain a healthy immune system. Orange juice is best enjoyed immediately after juicing, as oranges contain a substance called limonin, which can turn the juice bitter if left for too long. 

Grapes

Grapes are a popular choice with sweet-toothed juice fans. Seedless varieties are easier to blend, but if you find a seeded variety you particularly enjoy, you can remove the seeds by heating them on the stove until they split, then pushing the pulp through a sieve.

Pomegranates

Sometimes referred to as a superfood due to their high antioxidant content, pomegranates are another popular choice. They have a distinctive, sweet-tart flavour and a beautiful ruby-red colour, but they can be tricky to peel, so allow for some extra prep time.

Blueberries

Blueberries are another antioxidant-rich fruit, and they are also a great source of B vitamins. They have a delicate, fruity flavour, and an attractive blue colour. It would take a lot of blueberries to make a decent amount of juice, though, so they are often paired with other fruits like apples or cranberries.