The Effect of Product Quality, Price, and Halal Certification on The Sales Volume (Literature Review)

: The current globalization phenomenon provides significant opportunities for the development of the national economy. One of the impacts of the globalization phenomenon is the expansion of transactions in the global economy which has an impact on increasing market competition. In responding to this phenomenon, preparation is needed from business owner to increase sales of their products. Therefore, research is needed to determine the factor that affect sales volume. This literature review article is written to build a research hypothesis related to product sales volume that are influenced by product quality, price, and halal certification. The method used in writing the article is a library research method sourced from online media, such as Google Scholar, Mendeley and other academic online media. The results of this literature review article are product quality, price, and halal certification affect product sales volume.


INTRODUCTION
Advances in information and communication technology in the globalization process make it easier for all to carry out transactions.One of the ease of transactions obtained is the selling and purchasing of products.Various products derived from business units in any part of the world can be easily obtained through technological advances.
The number of business units, SMEs enterprises spread across all provinces in Indonesia has reached millions of units.This number does not include the number of business units from other countries.The globalization facilitated great movement between countries in creating open spaces and eliminating world economic borders.This has resulted in more diverse products being offered in the global market.
This diversity is challenging for business owner to increase the competitiveness of their products so that the sales volume remains stable and increases.The various ways can be done by business owner to increase the sales volume, including improving product quality, making price adjustments, and implementing halal certification.
To find the effect of product quality, price, and halal certification on the sales volume, a literature review study will be conducted.This study was conducted to find the theory of the relationship between variables through relevant literature in previous studies.
Based on the background the problem that has been raised is : 1.Does the product quality affect the sales volume? 2. Does the price affect the sales volume? 3. Does halal certification affect the sales volume?

LITERATURE REVIEW Sales
The sales are defined as achievements expressed quantitatively in terms of physical, volume, or units of a product (Rangkuti in Segati, 2018).In addition, sales can also be interpreted as the total goods or products sold by the company within a certain period of time (Marbun in Segati, 2018).In the sales activities, business owner give ownership of a commodity to consumers at a certain price (Segati, 2018).The indicators that affect the sales are price policy, market competition, and government policies (Segati, 2018).
Another definition of sales is the process carried out by business owner to ensure and fulfill consumer satisfaction in order to achieve sustainable and profitable benefits for both business owner and consumers (Winardi in Faizal, 2022).The sales can also be interpreted as an activity to deliver products to consumers (Suastha in Faizal, 2022).The sales volume's factor are price, service quality, and market conditions (Faizal, 2022).
Sulistiyowati in Rahim et al (2023) stated that sales escalation occurs when the demand for a product increases.This is strongly influenced by price, consumer preference, and income (Sulistiyowati in Rahim et al., 2023).

Product Quality
The definition of product quality is an effort to meet consumer expectations through quality standards that have been adjusted to consumer tastes (Doloksaribu and Wibowo, 2017).Product quality affects businesses to maintain their competitive advantage in the market (Kotler in Saribu and Maranatha, 2020).Business owner must know the dimensions of quality to maintain and improve the quality of their products.The dimensions of product quality consist of the shape, characteristics, performance, and functional aspects of the product, as well as product suitability which affects sales (Saribu and Maranatha, 2020).
Product quality can also be defined as the ability of goods to provide superior value and benefits desired by consumers (Abdullah et al. in Kusuma, 2021).Indicators that affect product quality are product value, preference, and consumer satisfaction (Kusuma, 2021).Widiarto and Hardiana (2021) argued that product quality is the first driver of consumer satisfaction and global dimension.There are five indicators that affect product quality, product performance, specification compatibility, product durability, and aesthetics (Tjiptono in Paramita, 2022).

Price
Price is the amount of money charged for a product (Sunyoto in Nasution et al, 2017).The pricing is important to deal with competition and limited consumer demand for products (Assauri in Nasution et al., 2017).The indicators of price are consumer demand, profit orientation, and competitor prices (Ningrum and Harti in Nasution et al., 2017).
Another definition of price is the amount of money needed to obtain a number of combinations of goods and services (Swastha in Puspitasari et al, 2018).The dimensions of price are price conformity to product quality, price conformity to product benefits, and competitive prices (Kotler in Muhtarom et al, 2022).Suharno and Sutarso in Lestari et al (2022) stated that price is part of a marketing strategy that affects revenue and sales volumes.Therefore, price is strongly influenced by product quality, competitiveness, and product affordability (Kotler in Lestari et al, 2022).

Halal Certification
Halal certification is defined as the recognition of the halalness of a product by Baand Penyelenggara Jaminan Produk Halal (BPJPH) which is based on a written fatwa issued by Majelis Ulama Indonesia (Panji in Warto and Syamsuri, 2020).Another definition of halal certification is a reference in giving halal status to products, so that it reassures consumers in buying and consuming (Segati, 2018).
Products that in the processing and production process have fulfilled safety and hygiene standards, will obtain a halal certificate issued by BPJPH (Faizal, 2022).The halal production process must be carried out continuously by business owner by implementing Sistem Jaminan Produk Halal (Rahim et al, 2023).

METHODS
This literature review article uses descriptive qualitative methods and library research.The literature sources come from the online applications such as Google Scholar, Mendeley, and other online academic applications.
In qualitative research, the literature review must be used consistently with methodological assumptions.For acquire the theories, the researcher must conduct a relevant literature review, sort out information that is suitable for the research topic, and organize it properly (Ridwan et al., 2021).

RESULT AND DISCUSSION
The literature review will conduct a review of the literature used to establish hypotheses, analyze the influence between variables, and create a conceptual framework for the research plan.

Previous Research Results
This review is used to determine hypotheses by explaining the results of previous research and describing the similarities and differences between previous research and the next plan research.The results of the literature review can be seen in the table below.The effect of product quality on the sales volume Product quality is something that is produced by business owner to fulfill the standards, preferences, and desires of consumers in order to create satisfaction.Products that that have good quality will affect the sales volume.
Based on Widiarto and Hardiana's research (2021), product quality significantly affects the product sales volume at ARB Bakery.This is closely related to consumers' positive perceptions of product quality.The best quality will increase consumer satisfaction and product sales volume.Therefore, product quality must be maintained and improved in order to increase sales volume.
From the results of research Saribu and Maranatha's research (2021), it is concluded that product quality can significantly affect product sales volume.The indicators that influence product quality on sales volume are shape, features, usability, excellence, durability, and design (Kotler and Keller in Lestari et al, 2022).

The effect of price on the sales volume
Price is one of the attributes of a product that influences consumer attitudes.In the certain level, consumers can get benefits and satisfaction from the products they have bought (Doloksaribu and Wibowo, 2017).The price suitability of the product will affect the sales volume due to increased consumer purchasing.
From the results of Puspitasari's research (2018), price has a positive influence on increasing sales of premium rice at Perum Bulog Regional North Sulawesi and Gorontalo.Price suitability for products is one of the marketing strategies to obtain increased sales volume.
According to Nasution, et al (2017), business owner who adjust the price of their products to the reach of consumers will get an increase in their sales volume.The pricing must be set in such a way as to achieve the target sales volume (Tjiptono in Nasution et al., 2017).The price compliance is influenced by product quality and design, production costs, and competitor prices (Nasution et al., 2017).

The effect of halal certification on the sales volume
Halal certification is the first step that needs to be taken by business owner to guarantee and ensure the safety and quality of their products.Business owner who want to obtain halal certification must implement Sistem Jaminan Produk Halal (SJPH) in their business activities.The principles in Sistem Jaminan Produk Halal are based the commitment of business owner, customer needs, improving product quality without increasing costs, without defects, without recycling, and without inspection (Prabowo and Rahman, 2016).
Based on the results of research conducted by Segati (2018), halal certification has a significant effect on the variable sales volume at Aqiqah Nurul Hayat Catering.Similar to Rahim et al. (2023), halal certification has a positive impact on increasing sales in the food and beverage industry sector.The halal certification is evidenced by the inclusion of the halal label on product packaging (Waskito in Faizal, 2022).Industries that implement halal certification and include halal labels on their product packaging will have a positive value in influencing sales increases.
Halal certification provides benefits for consumers, entrepreneurs, and the government (Warto and Syamsuri, 2020).Some of the benefits of halal certification include 1) Guarantee the safety of products consumed, 2) Unique Selling Point (USP), 3) Provides inner peace for consumers, 4) Provides comparative advantage, 5) Provides protection for products, 6) Gain access in the global market, and 7) Provide a better documentation and administration system.

Conceptual framework
Based on the problem statetment, theoretical studies, relevant previous research and discussion of the influence between variables, a conceptual framework is obtained as below.